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Balasenthilkumaran NV, Whitesell JC, Pyle L, Friedman RS, Kravets V. Network approach reveals preferential T-cell and macrophage association with α-linked β-cells in early stage of insulitis in NOD mice. FRONTIERS IN NETWORK PHYSIOLOGY 2024; 4:1393397. [PMID: 38979061 PMCID: PMC11228247 DOI: 10.3389/fnetp.2024.1393397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/21/2024] [Indexed: 07/10/2024]
Abstract
One of the challenges in studying islet inflammation-insulitis-is that it is a transient phenomenon. Traditional reporting of the insulitis progression is based on cumulative, donor-averaged values of leucocyte density in the vicinity of pancreatic islets, that hinder intra- and inter-islet heterogeneity of disease progression. Here, we aimed to understand why insulitis is non-uniform, often with peri-insulitis lesions formed on one side of an islet. To achieve this, we demonstrated the applicability of network theory in detangling intra-islet multi-cellular interactions during insulitis. Specifically, we asked the question "What is unique about regions of the islet that interact with immune cells first". This study utilized the non-obese diabetic mouse model of type one diabetes and examined the interplay among α-, β-, T-cells, myeloid cells, and macrophages in pancreatic islets during the progression of insulitis. Disease evolution was tracked based on the T/β cell ratio in individual islets. In the early stage, we found that immune cells are preferentially interacting with α-cell-rich regions of an islet. At the islet periphery α-linked β-cells were found to be targeted significantly more compared to those without α-cell neighbors. Additionally, network analysis revealed increased T-myeloid, and T-macrophage interactions with all β-cells.
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Affiliation(s)
- Nirmala V. Balasenthilkumaran
- Department of Bioengineering, Jacobs School of Engineering, University of California San Diego, San Diego, CA, United States
| | - Jennifer C. Whitesell
- Department of Immunology and Microbiology, School of Medicine, Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Laura Pyle
- Department of Pediatrics, University of Colorado School of Medicine, Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO, United States
| | - Rachel S. Friedman
- Department of Immunology and Microbiology, School of Medicine, Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Vira Kravets
- Department of Bioengineering, Jacobs School of Engineering, University of California San Diego, San Diego, CA, United States
- Department of Pediatrics, School of Medicine, University of California San Diego, San Diego, CA, United States
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Balasenthilkumaran NV, Whitesell JC, Pyle L, Friedman R, Kravets V. Network approach reveals preferential T-cell and macrophage association with α-linked β-cells in early stage of insulitis in NOD mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592831. [PMID: 38766090 PMCID: PMC11100702 DOI: 10.1101/2024.05.06.592831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
One of the challenges in studying islet inflammation - insulitis - is that it is a transient phenomenon. Traditional reporting of the insulitis progression is based on cumulative, donor-averaged values of leucocyte density in the vicinity of pancreatic islets, that hinders intra- and inter-islet heterogeneity of disease progression. Here, we aimed to understand why insulitis is non-uniform, often with peri-insulitis lesions formed on one side of an islet. To achieve this, we demonstrated applicability of network theory in detangling intra-islet multi-cellular interactions during insulitis. Specifically, we asked the question "what is unique about regions of the islet which interact with immune cells first". This study utilized the non-obese diabetic mouse model of type one diabetes and examined the interplay among α-, β-, T-cells, myeloid cells, and macrophages in pancreatic islets during the progression of insulitis. Disease evolution was tracked based on T/β cell ratio in individual islets. In the early stage, we found that immune cells are preferentially interacting with α-cell-rich regions of an islet. At the islet periphery α-linked β-cells were found to be targeted significantly more compared to those without α-cell neighbors. Additionally, network analysis revealed increased T-myeloid, and T-macrophage interactions with all β-cells.
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Waibel M, Wentworth JM, So M, Couper JJ, Cameron FJ, MacIsaac RJ, Atlas G, Gorelik A, Litwak S, Sanz-Villanueva L, Trivedi P, Ahmed S, Martin FJ, Doyle ME, Harbison JE, Hall C, Krishnamurthy B, Colman PG, Harrison LC, Thomas HE, Kay TWH. Baricitinib and β-Cell Function in Patients with New-Onset Type 1 Diabetes. N Engl J Med 2023; 389:2140-2150. [PMID: 38055252 DOI: 10.1056/nejmoa2306691] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
BACKGROUND Janus kinase (JAK) inhibitors, including baricitinib, block cytokine signaling and are effective disease-modifying treatments for several autoimmune diseases. Whether baricitinib preserves β-cell function in type 1 diabetes is unclear. METHODS In this phase 2, double-blind, randomized, placebo-controlled trial, we assigned patients with type 1 diabetes diagnosed during the previous 100 days to receive baricitinib (4 mg once per day) or matched placebo orally for 48 weeks. The primary outcome was the mean C-peptide level, determined from the area under the concentration-time curve, during a 2-hour mixed-meal tolerance test at week 48. Secondary outcomes included the change from baseline in the glycated hemoglobin level, the daily insulin dose, and measures of glycemic control assessed with the use of continuous glucose monitoring. RESULTS A total of 91 patients received baricitinib (60 patients) or placebo (31 patients). The median of the mixed-meal-stimulated mean C-peptide level at week 48 was 0.65 nmol per liter per minute (interquartile range, 0.31 to 0.82) in the baricitinib group and 0.43 nmol per liter per minute (interquartile range, 0.13 to 0.63) in the placebo group (P = 0.001). The mean daily insulin dose at 48 weeks was 0.41 U per kilogram of body weight per day (95% confidence interval [CI], 0.35 to 0.48) in the baricitinib group and 0.52 U per kilogram per day (95% CI, 0.44 to 0.60) in the placebo group. The levels of glycated hemoglobin were similar in the two trial groups. However, the mean coefficient of variation of the glucose level at 48 weeks, as measured by continuous glucose monitoring, was 29.6% (95% CI, 27.8 to 31.3) in the baricitinib group and 33.8% (95% CI, 31.5 to 36.2) in the placebo group. The frequency and severity of adverse events were similar in the two trial groups, and no serious adverse events were attributed to baricitinib or placebo. CONCLUSIONS In patients with type 1 diabetes of recent onset, daily treatment with baricitinib over 48 weeks appeared to preserve β-cell function as estimated by the mixed-meal-stimulated mean C-peptide level. (Funded by JDRF International and others; BANDIT Australian New Zealand Clinical Trials Registry number, ACTRN12620000239965.).
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Affiliation(s)
- Michaela Waibel
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - John M Wentworth
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Michelle So
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Jennifer J Couper
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Fergus J Cameron
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Richard J MacIsaac
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Gabby Atlas
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Alexandra Gorelik
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Sara Litwak
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Laura Sanz-Villanueva
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Prerak Trivedi
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Simi Ahmed
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Francis J Martin
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Madeleine E Doyle
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Jessica E Harbison
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Candice Hall
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Balasubramanian Krishnamurthy
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Peter G Colman
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Leonard C Harrison
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Helen E Thomas
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
| | - Thomas W H Kay
- From St. Vincent's Institute of Medical Research (M.W., M.S., S.L., L.S.-V., P.T., M.E.D., C.H., B.K., H.E.T., T.W.H.K.), St. Vincent's Hospital Melbourne (R.J.M., B.K., T.W.H.K.), and the Department of Medicine at St. Vincent's Hospital, University of Melbourne (R.J.M., L.S.-V., M.E.D., B.K., H.E.T., T.W.H.K.), Fitzroy, the Walter and Eliza Hall Institute of Medical Research (J.M.W., P.G.C., L.C.H.), the Departments of Medical Biology (J.M.W., L.C.H.) and Medicine (A.G.), University of Melbourne, the Royal Melbourne Hospital (J.M.W., M.S., C.H., P.G.C., L.C.H.), the Royal Children's Hospital (F.J.C., G.A.), and the Murdoch Children's Research Institute (F.J.C.), Parkville, and the School of Public Health and Preventive Medicine, Monash University, Melbourne (A.G.), VIC, and Women's and Children's Hospital (J.J.C., J.E.H.) and the University of Adelaide (J.J.C.), Adelaide, SA - all in Australia; the New York Stem Cell Foundation, New York (S.A.); and Macromoltek, Austin, TX (F.J.M.)
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Jose J, Law RHP, Leung EWW, Wai DCC, Akhlaghi H, Chandrashekaran IR, Caradoc-Davies TT, Voskoboinik I, Feutrill J, Middlemiss D, Jeevarajah D, Bashtannyk-Puhalovich T, Giddens AC, Lee TW, Jamieson SMF, Trapani JA, Whisstock JC, Spicer JA, Norton RS. Fragment-based and structure-guided discovery of perforin inhibitors. Eur J Med Chem 2023; 261:115786. [PMID: 37716187 DOI: 10.1016/j.ejmech.2023.115786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/24/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023]
Abstract
Perforin is a pore-forming protein whose normal function enables cytotoxic T and natural killer (NK) cells to kill virus-infected and transformed cells. Conversely, unwanted perforin activity can also result in auto-immune attack, graft rejection and aberrant responses to pathogens. Perforin is critical for the function of the granule exocytosis cell death pathway and is therefore a target for drug development. In this study, by screening a fragment library using NMR and surface plasmon resonance, we identified 4,4-diaminodiphenyl sulfone (dapsone) as a perforin ligand. We also found that dapsone has modest (mM) inhibitory activity of perforin lytic activity in a red blood cell lysis assay in vitro. Sequential modification of this lead fragment, guided by structural knowledge of the ligand binding site and binding pose, and supported by SPR and ligand-detected 19F NMR, enabled the design of nanomolar inhibitors of the cytolytic activity of intact NK cells against various tumour cell targets. Interestingly, the ligands we developed were largely inert with respect to direct perforin-mediated red blood cell lysis but were very potent in the context of perforin's action on delivering granzymes in the immune synapse, the context in which it functions physiologically. Our work indicates that a fragment-based, structure-guided drug discovery strategy can be used to identify novel ligands that bind perforin. Moreover, these molecules have superior physicochemical properties and solubility compared to previous generations of perforin ligands.
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Affiliation(s)
- Jiney Jose
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Eleanor W W Leung
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Hedieh Akhlaghi
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Indu R Chandrashekaran
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia
| | - Tom T Caradoc-Davies
- Australian Synchrotron, 800 Blackburn Rd., Clayton, Melbourne, VIC, 3168, Australia
| | - Ilia Voskoboinik
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - John Feutrill
- SYNthesis med chem (Australia) Pty Ltd, Bio21 Institute, 30 Flemington Road, Parkville, VIC, 3052, Australia
| | - David Middlemiss
- XaviaPharm, Bishop's Stortford, CM23 5EX, England, United Kingdom
| | - Devadharshini Jeevarajah
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | | | - Anna C Giddens
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Tet Woo Lee
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Stephen M F Jamieson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand; Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Joseph A Trapani
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia.
| | - Julie A Spicer
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia.
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Blagov AV, Summerhill VI, Sukhorukov VN, Popov MA, Grechko AV, Orekhov AN. Type 1 diabetes mellitus: Inflammation, mitophagy, and mitochondrial function. Mitochondrion 2023; 72:11-21. [PMID: 37453498 DOI: 10.1016/j.mito.2023.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/17/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023]
Abstract
Type 1 diabetes mellitus (T1DM) is a T-cell-mediated autoimmune disease characterized by the damage of insulin-secreting β-cells in the pancreatic islets of Langerhans. To date, its etiology is not fully understood, despite decades of active search for root causes, and that underlines the complexity of the disease pathogenesis. It was found that mitophagy plays a regulatory role in the development of autoimmune response during T1DM pathogenesis by preventing the accumulation of defective/dysfunctional mitochondria in pancreatic cells. Mitochondrial dysfunction due to impaired mitophagy with the release of mitochondrial reactive oxygen species (mtROS) and mitochondrial DNA (mtDNA) contributes to initiating an inflammatory response by elevating pro-inflammatory cytokines and interacting with receptors like those involved in the pathogen-associated response. Moreover, mtROS and mtDNA activate pathways leading to the development of chronic inflammation, which is tightly implicated in T1DM autoimmunity. In this review, we summarized the evidence highlighting the functional role of mitophagy and mitochondria in the development of immune response and chronic inflammation during T1DM pathogenesis. Several anti-inflammatory and mitophagy-related treatment options have been explored.
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Affiliation(s)
- Alexander V Blagov
- Institute of General Pathology and Pathophysiology, 8, Baltiiskaya Street, Moscow 125315, Russia.
| | - Volha I Summerhill
- Institute for Atherosclerosis Research, Osennyaya Street 4-1-207, Moscow 121609, Russia.
| | - Vasily N Sukhorukov
- Institute of General Pathology and Pathophysiology, 8, Baltiiskaya Street, Moscow 125315, Russia; Institute for Atherosclerosis Research, Osennyaya Street 4-1-207, Moscow 121609, Russia.
| | - Mikhail A Popov
- Department of Cardiac Surgery, Moscow Regional Research and Clinical Institute (MONIKI), 61/2, Shchepkin Street, Moscow 129110, Russia.
| | - Andrey V Grechko
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, 14-3, Solyanka Street, Moscow 109240, Russia.
| | - Alexander N Orekhov
- Institute of General Pathology and Pathophysiology, 8, Baltiiskaya Street, Moscow 125315, Russia; Institute for Atherosclerosis Research, Osennyaya Street 4-1-207, Moscow 121609, Russia.
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6
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De George DJ, Ge T, Krishnamurthy B, Kay TWH, Thomas HE. Inflammation versus regulation: how interferon-gamma contributes to type 1 diabetes pathogenesis. Front Cell Dev Biol 2023; 11:1205590. [PMID: 37293126 PMCID: PMC10244651 DOI: 10.3389/fcell.2023.1205590] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 05/15/2023] [Indexed: 06/10/2023] Open
Abstract
Type 1 diabetes is an autoimmune disease with onset from early childhood. The insulin-producing pancreatic beta cells are destroyed by CD8+ cytotoxic T cells. The disease is challenging to study mechanistically in humans because it is not possible to biopsy the pancreatic islets and the disease is most active prior to the time of clinical diagnosis. The NOD mouse model, with many similarities to, but also some significant differences from human diabetes, provides an opportunity, in a single in-bred genotype, to explore pathogenic mechanisms in molecular detail. The pleiotropic cytokine IFN-γ is believed to contribute to pathogenesis of type 1 diabetes. Evidence of IFN-γ signaling in the islets, including activation of the JAK-STAT pathway and upregulation of MHC class I, are hallmarks of the disease. IFN-γ has a proinflammatory role that is important for homing of autoreactive T cells into islets and direct recognition of beta cells by CD8+ T cells. We recently showed that IFN-γ also controls proliferation of autoreactive T cells. Therefore, inhibition of IFN-γ does not prevent type 1 diabetes and is unlikely to be a good therapeutic target. In this manuscript we review the contrasting roles of IFN-γ in driving inflammation and regulating the number of antigen specific CD8+ T cells in type 1 diabetes. We also discuss the potential to use JAK inhibitors as therapy for type 1 diabetes, to inhibit both cytokine-mediated inflammation and proliferation of T cells.
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Affiliation(s)
- David J. De George
- Immunology and Diabetes Unit, St Vincent’s Institute, Fitzroy, VIC, Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC, Australia
| | - Tingting Ge
- Immunology and Diabetes Unit, St Vincent’s Institute, Fitzroy, VIC, Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC, Australia
| | - Balasubramaniam Krishnamurthy
- Immunology and Diabetes Unit, St Vincent’s Institute, Fitzroy, VIC, Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC, Australia
| | - Thomas W. H. Kay
- Immunology and Diabetes Unit, St Vincent’s Institute, Fitzroy, VIC, Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC, Australia
| | - Helen E. Thomas
- Immunology and Diabetes Unit, St Vincent’s Institute, Fitzroy, VIC, Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC, Australia
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7
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Garavelli S, Prattichizzo F, Ceriello A, Galgani M, de Candia P. Type 1 Diabetes and Associated Cardiovascular Damage: Contribution of Extracellular Vesicles in Tissue Crosstalk. Antioxid Redox Signal 2022; 36:631-651. [PMID: 34407376 DOI: 10.1089/ars.2021.0053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Significance: Type 1 diabetes (T1D) is characterized by the autoimmune destruction of the insulin secreting β-cells, with consequent aberrant blood glucose levels. Hyperglycemia is the common denominator for most of the chronic diabetic vascular complications, which represent the main cause of life reduction in T1D patients. For this disease, three interlaced medical needs remain: understanding the underlying mechanisms involved in pancreatic β-cell loss; identifying biomarkers able to predict T1D progression and its related complications; recognizing novel therapeutic targets. Recent Advances: Extracellular vesicles (EVs), released by most cell types, were discovered to contain a plethora of different molecules (including microRNAs) with regulatory properties, which are emerging as mediators of cell-to-cell communication at the paracrine and endocrine level. Recent knowledge suggests that EVs may act as pathogenic factors, and be developed into disease biomarkers and therapeutic targets in the context of several human diseases. Critical Issues: EVs have been recently shown to sustain a dysregulated cellular crosstalk able to exacerbate the autoimmune response in the pancreatic islets of T1D; moreover, EVs were shown to be able to monitor and/or predict the progression of T1D and the insurgence of vasculopathies. Future Directions: More mechanistic studies are needed to investigate whether the dysregulation of EVs in T1D patients is solely reflecting the progression of diabetes and related complications, or EVs also directly participate in the disease process, thus pointing to a potential use of EVs as therapeutic targets/tools in T1D. Antioxid. Redox Signal. 36, 631-651.
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Affiliation(s)
- Silvia Garavelli
- Institute for Endocrinology and Experimental Oncology "G. Salvatore," Consiglio Nazionale delle Ricerche (C.N.R.), Naples, Italy
| | | | | | - Mario Galgani
- Institute for Endocrinology and Experimental Oncology "G. Salvatore," Consiglio Nazionale delle Ricerche (C.N.R.), Naples, Italy.,Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II," Italy
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8
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Amdare N, Purcell AW, DiLorenzo TP. Noncontiguous T cell epitopes in autoimmune diabetes: From mice to men and back again. J Biol Chem 2021; 297:100827. [PMID: 34044020 PMCID: PMC8233151 DOI: 10.1016/j.jbc.2021.100827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 11/30/2022] Open
Abstract
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that affects the insulin-producing beta cells of the pancreatic islets. The nonobese diabetic mouse is a widely studied spontaneous model of the disease that has contributed greatly to our understanding of T1D pathogenesis. This is especially true in the case of antigen discovery. Upon review of existing knowledge concerning the antigens and peptide epitopes that are recognized by T cells in this model, good concordance is observed between mouse and human antigens. A fascinating recent illustration of the contribution of the nonobese diabetic mouse in the area of epitope identification is the discovery of noncontiguous CD4+ T cell epitopes. This novel epitope class is characterized by the linkage of an insulin-derived peptide to, most commonly, a fragment of a natural cleavage product of another beta cell secretory granule constituent. These so-called hybrid insulin peptides are also recognized by T cells in patients with T1D, although the precise mechanism for their generation has yet to be defined and is the subject of active investigation. Although evidence from the tumor immunology arena documented the existence of noncontiguous CD8+ T cell epitopes, generated by proteasome-mediated peptide splicing involving transpeptidation, such CD8+ T cell epitopes were thought to be a rare immunological curiosity. However, recent advances in bioinformatics and mass spectrometry have challenged this view. These developments, coupled with the discovery of hybrid insulin peptides, have spurred a search for noncontiguous CD8+ T cell epitopes in T1D, an exciting frontier area still in its infancy.
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Affiliation(s)
- Nitin Amdare
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Teresa P DiLorenzo
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA; Division of Endocrinology, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, USA; Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York, USA; The Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, New York, USA.
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Cytocidal macrophages in symbiosis with CD4 and CD8 T cells cause acute diabetes following checkpoint blockade of PD-1 in NOD mice. Proc Natl Acad Sci U S A 2020; 117:31319-31330. [PMID: 33229539 DOI: 10.1073/pnas.2019743117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Autoimmune diabetes is one of the complications resulting from checkpoint blockade immunotherapy in cancer patients, yet the underlying mechanisms for such an adverse effect are not well understood. Leveraging the diabetes-susceptible nonobese diabetic (NOD) mouse model, we phenocopy the diabetes progression induced by programmed death 1 (PD-1)/PD-L1 blockade and identify a cascade of highly interdependent cellular interactions involving diabetogenic CD4 and CD8 T cells and macrophages. We demonstrate that exhausted CD8 T cells are the major cells that respond to PD-1 blockade producing high levels of IFN-γ. Most importantly, the activated T cells lead to the recruitment of monocyte-derived macrophages that become highly activated when responding to IFN-γ. These macrophages acquire cytocidal activity against β-cells via nitric oxide and induce autoimmune diabetes. Collectively, the data in this study reveal a critical role of macrophages in the PD-1 blockade-induced diabetogenesis, providing new insights for the understanding of checkpoint blockade immunotherapy in cancer and infectious diseases.
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10
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IL-21 regulates SOCS1 expression in autoreactive CD8 + T cells but is not required for acquisition of CTL activity in the islets of non-obese diabetic mice. Sci Rep 2019; 9:15302. [PMID: 31653894 PMCID: PMC6814838 DOI: 10.1038/s41598-019-51636-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/30/2019] [Indexed: 12/17/2022] Open
Abstract
In type 1 diabetes, maturation of activated autoreactive CD8+ T cells to fully armed effector cytotoxic T lymphocytes (CTL) occurs within the islet. At present the signals required for the maturation process are poorly defined. Cytokines could potentially provide the necessary "third signal" required to generate fully mature CTL capable of killing insulin-producing β-cells. To determine whether autoreactive CTL within islets respond to cytokines we generated non-obese diabetic (NOD) mice with a reporter for cytokine signalling. These mice express a reporter gene, hCD4, under the control of the endogenous regulatory elements for suppressor of cytokine signalling (SOCS)1, which is itself regulated by pro-inflammatory cytokines. In NOD mice, the hCD4 reporter was expressed in infiltrated islets and the expression level was positively correlated with the frequency of infiltrating CD45+ cells. SOCS1 reporter expression was induced in transferred β-cell-specific CD8+ 8.3T cells upon migration from pancreatic draining lymph nodes into islets. To determine which cytokines induced SOCS1 promoter activity in islets, we examined hCD4 reporter expression and CTL maturation in the absence of the cytokine receptors IFNAR1 or IL-21R. We show that IFNAR1 deficiency does not confer protection from diabetes in 8.3 TCR transgenic mice, nor is IFNAR1 signalling required for SOCS1 reporter upregulation or CTL maturation in islets. In contrast, IL-21R-deficient 8.3 mice have reduced diabetes incidence and reduced SOCS1 reporter activity in islet CTLs. However IL-21R deficiency did not affect islet CD8+ T cell proliferation or expression of granzyme B or IFNγ. Together these data indicate that autoreactive CD8+ T cells respond to IL-21 and not type I IFNs in the islets of NOD mice, but neither IFNAR1 nor IL-21R are required for islet intrinsic CTL maturation.
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11
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Pillai SS, Mini S. Attenuation of high glucose induced apoptotic and inflammatory signaling pathways in RIN-m5F pancreatic β cell lines by Hibiscus rosa sinensis L. petals and its phytoconstituents. JOURNAL OF ETHNOPHARMACOLOGY 2018; 227:8-17. [PMID: 30120944 DOI: 10.1016/j.jep.2018.08.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/25/2018] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Hibiscus rosa sinensis petals possess wide range of pharmacological properties, with remarkable nutritional values. Diabetes is one of the most devastating diseases affecting the world today. A few side effects associated with the use of insulin and oral hypoglycemic agents prompted us to search new bioactive principles from antidiabetic plants used in traditional medicine. AIM OF THE STUDY The anti-diabetic therapeutic potential of the flavonoids rich ethyl acetate fraction of Hibiscus rosa sinensis petals (EHRS) was evaluated. MATERIALS AND METHODS High glucose (25 mM) induced apoptotic model of diabetes in RIN-m5F pancreatic β-cells was used for the study. RESULTS EHRS elevated the release of insulin in pancreatic cells and modulated apoptotic signaling cascades. It significantly reduced NF-κB nuclear translocation, thereby down-regulated the expressions of major inflammatory cytokines and up-regulated expressions of pancreatic β-cell functional genes such as, foxO-1, Ucn-3, Pdx-1, MafA and Nkx6.1. On comparison with its constituent phytochemicals, superior protective effect shown by EHRS may be due to the additive action of these phytoconstituents. CONCLUSIONS Results of the present study suggest hibiscus petals as a natural source and functional food of potential therapeutics to protect pancreatic β-cells in experimental diabetes mellitus.
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Affiliation(s)
- Sneha S Pillai
- Department of Biochemistry, University of Kerala, Thiruvananthapuram, Kerala 695581, India.
| | - S Mini
- Department of Biochemistry, University of Kerala, Thiruvananthapuram, Kerala 695581, India.
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12
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Chen J, Stimpson SE, Fernandez-Bueno GA, Mathews CE. Mitochondrial Reactive Oxygen Species and Type 1 Diabetes. Antioxid Redox Signal 2018; 29:1361-1372. [PMID: 29295631 PMCID: PMC6166689 DOI: 10.1089/ars.2017.7346] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
SIGNIFICANCE The complex etiology of type 1 diabetes (T1D) is the outcome of failures in regulating immunity in combination with beta cell perturbations. Mitochondrial dysfunction in beta cells and immune cells may be involved in T1D pathogenesis. Mitochondrial energy production is essential for the major task of beta cells (the secretion of insulin in response to glucose). Mitochondria are a major site of reactive oxygen species (ROS) production. Under immune attack, mitochondrial ROS (mtROS) participate in beta cell damage. Similarly, T cell fate during immune responses is tightly regulated by mitochondrial physiology, morphology, and metabolism. Production of mtROS is essential for signaling in antigen-specific T cell activation. Mitochondrial dysfunction in T cells has been noted as a feature of some human autoimmune diseases. Recent Advances: Preclinical and clinical studies indicate that mitochondrial dysfunction in beta cells sensitizes these cells to immune-mediated destruction via direct or indirect mechanisms. Sensitivity of beta cells to mtROS is associated with genetic T1D risk loci in human and the T1D-prone nonobese diabetic (NOD) mouse. Mitochondrial dysfunction and altered metabolism have also been observed in immune cells of NOD mice and patients with T1D. This immune cell mitochondrial dysfunction has been linked to deleterious functional changes. CRITICAL ISSUES It remains unclear how mitochondria control T cell receptor signaling and downstream events, including calcium flux and activation of transcription factors during autoimmunity. FUTURE DIRECTIONS Mechanistic studies are needed to investigate the mitochondrial pathways involved in autoimmunity, including T1D. These studies should seek to identify the role of mitochondria in regulating innate and adaptive immune cell activity and beta cell failure.
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Affiliation(s)
- Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Scott E Stimpson
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Gabriel A Fernandez-Bueno
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine , Gainesville, Florida
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13
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Bhat P, Bergot AS, Waterhouse N, Frazer IH. Human papillomavirus E7 oncoprotein expression by keratinocytes alters the cytotoxic mechanisms used by CD8 T cells. Oncotarget 2018; 9:6015-6027. [PMID: 29464051 PMCID: PMC5814191 DOI: 10.18632/oncotarget.23210] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/17/2017] [Indexed: 11/25/2022] Open
Abstract
Cervical cancer is a malignant transformation of keratinocytes initiated by the E7 oncoprotein of human papillomavirus (HPV). These tumors are characterized by keratinocyte hyperproliferation and are often infiltrated with activated CD8 T cells. HPV infection confers changes to gain immunological advantage to promote chronic infection, and these persist with malignant transformation. We investigated the relative importance of the many redundant mechanisms of cytotoxicity used by CD8 T cells to kill keratinocytes expressing HPV E7 oncoprotein using extended-duration time-lapse microscopy that allows examination of cell-to-cell interactions during killing. E7 expression by keratinocytes increased susceptibility to cell-mediated killing. However, while killing of non-transgenic keratinocytes was traditional, perforin-mediated, and caspase-dependent, E7-expression favored killing by perforin-independent, caspase-independent mechanisms. The roles of perforin, TNFα, IFNγ, Fas/FasL and PD1/PD-L1 were graded according to target cell survival to produce a hierarchy of killing mechanisms utilized in killing E7-expressing cells. TNFα was essential for perforin-mediated killing of E7-expressing cells, but not perforin-independent killing. IFNγ facilitated killing by Fas/FasL interaction, especially in the absence of perforin. Additionally, expression of E7 offered protection from killing by up regulation of PD-L1, Fas and FasL expression on keratinocytes promoting fight-back by target cells, resulting in effector cell death. This study shows that keratinocytes expressing E7 are highly susceptible to killing by CD8 T cells, but utilizing different armamentarium. Down-regulation of CD8 T cell cytotoxicity in HPV-related tumors may be due to suppression by E7-expressing keratinocytes. Immunotherapy for HPV-related cancers may be improved by suppression of PD-L1, or by suppression of FasL.
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Affiliation(s)
- Purnima Bhat
- University of Queensland Diamantina Institute, University of Queensland, Translational Research Institute, Brisbane, Qld, Australia.,Medical School, Australian National University, Canberra, Act, Australia
| | - Anne-Sophie Bergot
- University of Queensland Diamantina Institute, University of Queensland, Translational Research Institute, Brisbane, Qld, Australia
| | - Nigel Waterhouse
- QIMR Berghofer Medical Research Institute, Brisbane, Qld, Australia
| | - Ian Hector Frazer
- University of Queensland Diamantina Institute, University of Queensland, Translational Research Institute, Brisbane, Qld, Australia
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14
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Stanley WJ, Trivedi PM, Sutherland AP, Thomas HE, Gurzov EN. Differential regulation of pro-inflammatory cytokine signalling by protein tyrosine phosphatases in pancreatic β-cells. J Mol Endocrinol 2017; 59:325-337. [PMID: 28827413 DOI: 10.1530/jme-17-0089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 08/21/2017] [Indexed: 01/19/2023]
Abstract
Type 1 diabetes (T1D) is characterized by the destruction of insulin-producing β-cells by immune cells in the pancreas. Pro-inflammatory including TNF-α, IFN-γ and IL-1β are released in the islet during the autoimmune assault and signal in β-cells through phosphorylation cascades, resulting in pro-apoptotic gene expression and eventually β-cell death. Protein tyrosine phosphatases (PTPs) are a family of enzymes that regulate phosphorylative signalling and are associated with the development of T1D. Here, we observed expression of PTPN6 and PTPN1 in human islets and islets from non-obese diabetic (NOD) mice. To clarify the role of these PTPs in β-cells/islets, we took advantage of CRISPR/Cas9 technology and pharmacological approaches to inactivate both proteins. We identify PTPN6 as a negative regulator of TNF-α-induced β-cell death, through JNK-dependent BCL-2 protein degradation. In contrast, PTPN1 acts as a positive regulator of IFN-γ-induced STAT1-dependent gene expression, which enhanced autoimmune destruction of β-cells. Importantly, PTPN1 inactivation by pharmacological modulation protects β-cells and primary mouse islets from cytokine-mediated cell death. Thus, our data point to a non-redundant effect of PTP regulation of cytokine signalling in β-cells in autoimmune diabetes.
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Affiliation(s)
- William J Stanley
- St. Vincent's Institute of Medical ResearchMelbourne, Australia
- Department of MedicineSt. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | - Prerak M Trivedi
- St. Vincent's Institute of Medical ResearchMelbourne, Australia
- Department of MedicineSt. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | | | - Helen E Thomas
- St. Vincent's Institute of Medical ResearchMelbourne, Australia
- Department of MedicineSt. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | - Esteban N Gurzov
- St. Vincent's Institute of Medical ResearchMelbourne, Australia
- Department of MedicineSt. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
- ULB Center for Diabetes ResearchUniversite Libre de Bruxelles (ULB), Brussels, Belgium
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15
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Dlamini Z, Mokoena F, Hull R. Abnormalities in alternative splicing in diabetes: therapeutic targets. J Mol Endocrinol 2017; 59:R93-R107. [PMID: 28716821 DOI: 10.1530/jme-17-0049] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022]
Abstract
Diabetes mellitus (DM) is a non-communicable, metabolic disorder that affects 416 million individuals worldwide. Type 2 diabetes contributes to a vast 85-90% of the diabetes incidences while 10-15% of patients suffer from type 1 diabetes. These two predominant forms of DM cause a significant loss of functional pancreatic β-cell mass causing different degrees of insulin deficiency, most likely, due to increased β-cell apoptosis. Treatment options involve the use of insulin sensitisers, α-glucosidase inhibitors, and β-cell secretagogues which are often expensive, limited in efficacy and carry detrimental adverse effects. Cost-effective options for treatment exists in the form of herbal drugs, however, scientific validations of these widely used medicinal plants are still underway. Alternative splicing (AS) is a co-ordinated post-transcriptional process in which a single gene generates multiple mRNA transcripts which results in increased amounts of functionally different protein isoforms and in some cases aberrant splicing leads to metabolic disease. In this review, we explore the association of AS with metabolic alterations in DM and the biological significance of the abnormal splicing of some pathogenic diabetes-related genes. An understanding of the molecular mechanism behind abnormally spliced transcripts will aid in the development of new diagnostic, prognostic and therapeutic tools.
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Affiliation(s)
- Zodwa Dlamini
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
| | - Fortunate Mokoena
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
| | - Rodney Hull
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
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16
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Abstract
PURPOSE OF REVIEW Type 1 diabetes (T1D) is an autoimmune disease marked by β-cell destruction. Immunotherapies for T1D have been investigated since the 1980s and have focused on restoration of tolerance, T cell or B cell inhibition, regulatory T cell (Treg) induction, suppression of innate immunity and inflammation, immune system reset, and islet transplantation. The purpose of this review is to provide an overview and lessons learned from single immunotherapy trials, describe recent and ongoing combination immunotherapy trials, and provide perspectives on strategies for future combination clinical interventions aimed at preserving insulin secretion in T1D. RECENT FINDINGS Combination immunotherapies have had mixed results in improving short-term glycemic control and insulin secretion in recent-onset T1D. A handful of studies have successfully reached their primary end-point of improved insulin secretion in recent-onset T1D. However, long-term improvements glycemic control and the restoration of insulin independence remain elusive. Future interventions should focus on strategies that combine immunomodulation with efforts to alleviate β-cell stress and address the formation of antigens that activate autoimmunity.
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Affiliation(s)
- Robert N Bone
- Department of Medicine, Indiana School of Medicine, 635 Barnhill Dr, MS 2031A, Indianapolis, IN, 46202, USA
- Center for Diabetes & Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Carmella Evans-Molina
- Department of Medicine, Indiana School of Medicine, 635 Barnhill Dr, MS 2031A, Indianapolis, IN, 46202, USA.
- Center for Diabetes & Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Cellular & Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Roudebush VA Medical Center, Indianapolis, IN, 46202, USA.
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17
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Trivedi PM, Graham KL, Scott NA, Jenkins MR, Majaw S, Sutherland RM, Fynch S, Lew AM, Burns CJ, Krishnamurthy B, Brodnicki TC, Mannering SI, Kay TW, Thomas HE. Repurposed JAK1/JAK2 Inhibitor Reverses Established Autoimmune Insulitis in NOD Mice. Diabetes 2017; 66:1650-1660. [PMID: 28292965 DOI: 10.2337/db16-1250] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 03/07/2017] [Indexed: 12/11/2022]
Abstract
Recent advances in immunotherapeutics have not yet changed the routine management of autoimmune type 1 diabetes. There is an opportunity to repurpose therapeutics used to treat other diseases to treat type 1 diabetes, especially when there is evidence for overlapping mechanisms. Janus kinase (JAK) 1/JAK2 inhibitors are in development or clinical use for indications including rheumatoid arthritis. There is good evidence for activation of the JAK1/JAK2 and signal transducer and activator of transcription (STAT) 1 pathway in human type 1 diabetes and in mouse models, especially in β-cells. We tested the hypothesis that using these drugs to block the JAK-STAT pathway would prevent autoimmune diabetes. The JAK1/JAK2 inhibitor AZD1480 blocked the effect of cytokines on mouse and human β-cells by inhibiting MHC class I upregulation. This prevented the direct interaction between CD8+ T cells and β-cells, and reduced immune cell infiltration into islets. NOD mice treated with AZD1480 were protected from autoimmune diabetes, and diabetes was reversed in newly diagnosed NOD mice. This provides mechanistic groundwork for repurposing clinically approved JAK1/JAK2 inhibitors for type 1 diabetes.
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Affiliation(s)
- Prerak M Trivedi
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Kate L Graham
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Nicholas A Scott
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Misty R Jenkins
- Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
- The Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | | | - Robyn M Sutherland
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The Walter and Eliza Hall Institute, Parkville, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Stacey Fynch
- St. Vincent's Institute, Fitzroy, Victoria, Australia
| | - Andrew M Lew
- The Walter and Eliza Hall Institute, Parkville, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Balasubramanian Krishnamurthy
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Thomas C Brodnicki
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Stuart I Mannering
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Thomas W Kay
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Helen E Thomas
- St. Vincent's Institute, Fitzroy, Victoria, Australia
- The University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
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18
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Ghafari S, Komeilian M, Hashemi MS, Oushani S, Rigi G, Rashidieh B, Yarahmadi K, Khoddam F. Molecular docking based screening of Listeriolysin-O for improved inhibitors. Bioinformation 2017; 13:160-163. [PMID: 28690383 PMCID: PMC5498783 DOI: 10.6026/97320630013160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 04/23/2017] [Accepted: 04/23/2017] [Indexed: 12/30/2022] Open
Abstract
Listeriolysine-O (LLO) is a 50KDa protein responsible for Listeria monocytogenes pathogenicity. The structure of LLO (PDB ID: 4CDB) with domains D1 to D4 is known. Therefore, it is of interest to identify conserved regions among LLO variants for destabilizing oligomerization (50 mer complex) of its monomers using appropriate inhibitors. Therefore, it is of interest to identify suitable inhibitors for inhibiting LLO. Previous reports suggest the use of flavanoids like compounds for inhibiting LLO. Our interest is to identify improved compounds to destabilize LLO oligomerization. We used a library (Zinc database) containing 200,000 drug-like compounds against LLO using molecular docking based screening. This resulted in five hits that were further analyzed for pharmacological properties. The hit #1 (2-methyloctadecane- 1, 3, 4-triol) was further refined using appropriate modifications for creating a suitable pharmacophore model LLO inhibition. The modified compound (1-(4-Cyclopent-3-enyl-6, 7-dihydroxy-8-hydroxymethyl-nona-2, 8-dienylideneamino)-penta-1,4-dien-3-one) shows fitting binding properties with LLO with no undesirable pharmacological properties such as toxicity.
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Affiliation(s)
| | | | | | | | - Garshasb Rigi
- Department of Biology, Faculty of Science, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran
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19
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Joglekar MV, Trivedi PM, Kay TW, Hawthorne WJ, O'Connell PJ, Jenkins AJ, Hardikar AA, Thomas HE. Human islet cells are killed by BID-independent mechanisms in response to FAS ligand. Apoptosis 2016; 21:379-89. [PMID: 26758067 DOI: 10.1007/s10495-016-1212-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cell death via FAS/CD95 can occur either by activation of caspases alone (extrinsic) or by activation of mitochondrial death signalling (intrinsic) depending on the cell type. The BH3-only protein BID is activated in the BCL-2-regulated or mitochondrial apoptosis pathway and acts as a switch between the extrinsic and intrinsic cell death pathways. We have previously demonstrated that islets from BID-deficient mice are protected from FAS ligand-mediated apoptosis in vitro. However, it is not yet known if BID plays a similar role in human beta cell death. We therefore aimed to test the role of BID in human islet cell apoptosis immediately after isolation from human cadaver donors, as well as after de-differentiation in vitro. Freshly isolated human islets or 10-12 day cultured human islet cells exhibited BID transcript knockdown after BID siRNA transfection, however they were not protected from FAS ligand-mediated cell death in vitro as determined by DNA fragmentation analysis using flow cytometry. On the other hand, the same cells transfected with siRNA for FAS-associated via death domain (FADD), a molecule in the extrinsic cell death pathway upstream of BID, showed significant reduction in cell death. De-differentiated islets (human islet-derived progenitor cells) also demonstrated similar results with no difference in cell death after BID knockdown as compared to scramble siRNA transfections. Our results indicate that BID-independent pathways are responsible for FAS-dependent human islet cell death. These results are different from those observed in mouse islets and therefore demonstrate potentially alternate pathways of FAS ligand-induced cell death in human and mouse islet cells.
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Affiliation(s)
- Mugdha V Joglekar
- Diabetes and Islet Biology Group, NHMRC-Clinical Trials Centre, University of Sydney, Camperdown, Australia
| | - Prerak M Trivedi
- St. Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Melbourne, VIC, 3065, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | - Thomas W Kay
- St. Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Melbourne, VIC, 3065, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | - Wayne J Hawthorne
- The Centre for Transplant and Renal Research, Westmead Millennium Research Institute, University of Sydney, Westmead, Australia
| | - Philip J O'Connell
- The Centre for Transplant and Renal Research, Westmead Millennium Research Institute, University of Sydney, Westmead, Australia
| | - Alicia J Jenkins
- Diabetes and Islet Biology Group, NHMRC-Clinical Trials Centre, University of Sydney, Camperdown, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Australia
| | - Anandwardhan A Hardikar
- Diabetes and Islet Biology Group, NHMRC-Clinical Trials Centre, University of Sydney, Camperdown, Australia
| | - Helen E Thomas
- St. Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Melbourne, VIC, 3065, Australia. .,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Australia.
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20
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Perforin facilitates beta cell killing and regulates autoreactive CD8+ T-cell responses to antigen in mouse models of type 1 diabetes. Immunol Cell Biol 2015; 94:334-41. [PMID: 26446877 DOI: 10.1038/icb.2015.89] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/15/2015] [Accepted: 10/01/2015] [Indexed: 02/05/2023]
Abstract
In type 1 diabetes, cytotoxic CD8(+) T lymphocytes (CTLs) directly interact with pancreatic beta cells through major histocompatibility complex class I. An immune synapse facilitates delivery of cytotoxic granules, comprised mainly of granzymes and perforin. Perforin deficiency protects the majority of non-obese diabetic (NOD) mice from autoimmune diabetes. Intriguingly perforin deficiency does not prevent diabetes in CD8(+) T-cell receptor transgenic NOD8.3 mice. We therefore investigated the importance of perforin-dependent killing via CTL-beta cell contact in autoimmune diabetes. Perforin-deficient CTL from NOD mice or from NOD8.3 mice were significantly less efficient at adoptive transfer of autoimmune diabetes into NODRag1(-/-) mice, confirming that perforin is essential to facilitate beta cell destruction. However, increasing the number of transferred in vitro-activated perforin-deficient 8.3 T cells reversed the phenotype and resulted in diabetes. Perforin-deficient NOD8.3 T cells were present in increased proportion in islets, and proliferated more in response to antigen in vivo indicating that perforin may regulate the activation of CTLs, possibly by controlling cytokine production. This was confirmed when we examined the requirement for direct interaction between beta cells and CD8(+) T cells in NOD8.3 mice, in which beta cells specifically lack major histocompatibility complex (MHC) class I through conditional deletion of β2-microglobulin. Although diabetes was significantly reduced, 40% of these mice developed diabetes, indicating that NOD8.3 T cells can kill beta cells in the absence of direct interaction. Our data indicate that although perforin delivery is the main mechanism that CTL use to destroy beta cells, they can employ alternative mechanisms to induce diabetes in a perforin-independent manner.
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21
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Gene therapy with neurogenin3, betacellulin and SOCS1 reverses diabetes in NOD mice. Gene Ther 2015; 22:876-82. [PMID: 26172077 PMCID: PMC4636470 DOI: 10.1038/gt.2015.62] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 05/18/2015] [Accepted: 06/15/2015] [Indexed: 01/23/2023]
Abstract
Islet transplantation for Type 1 diabetes is limited by a shortage of donor islets and requirement for immunosuppression. We approached this problem by inducing in vivo islet neogenesis in NOD diabetic mice, a model of autoimmune diabetes. We demonstrate that gene therapy with helper-dependent adenovirus (HDAd) carrying neurogenin3, an islet lineage-defining transcription factor and betacellulin, an islet growth factor, leads to the induction of periportal insulin-positive cell clusters in the liver, which are rapidly destroyed. To specifically accord protection to these ‘neo-islets’ from cytokine-mediated destruction, we overexpressed suppressor of cytokine signaling 1 (SOCS1) gene, using a rat insulin promoter in combination with neurogenin3 and betacellulin. With this approach, about half of diabetic mice attained euglycemia sustained for over 4 months, regain glucose tolerance and appropriate glucose-stimulated insulin secretion. Histological analysis revealed periportal islet hormone-expressing ‘neo-islets’ in treated mouse livers. Despite evidence of persistent ‘insulitis’ with activated T-cells, these ‘neo-islets’ persist to maintain euglycemia. This therapy does not affect diabetogenicity of splenocytes, as they retain the ability to transfer diabetes. This study thus provides a proof-of-concept for engineering in vivo islet neogenesis with targeted resistance to cytokine-mediated destruction to provide a long-term reversal of diabetes in NOD mice.
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22
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Zhao Y, Scott NA, Quah HS, Krishnamurthy B, Bond F, Loudovaris T, Mannering SI, Kay TWH, Thomas HE. Mouse pancreatic beta cells express MHC class II and stimulate CD4(+) T cells to proliferate. Eur J Immunol 2015; 45:2494-503. [PMID: 25959978 DOI: 10.1002/eji.201445378] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 03/25/2015] [Accepted: 05/07/2015] [Indexed: 11/05/2022]
Abstract
Type 1 diabetes results from destruction of pancreatic beta cells by autoreactive T cells. Both CD4(+) and CD8(+) T cells have been shown to mediate beta-cell killing. While CD8(+) T cells can directly recognize MHC class I on beta cells, the interaction between CD4(+) T cells and beta cells remains unclear. Genetic association studies have strongly implicated HLA-DQ alleles in human type 1 diabetes. Here we studied MHC class II expression on beta cells in nonobese diabetic mice that were induced to develop diabetes by diabetogenic CD4(+) T cells with T-cell receptors that recognize beta-cell antigens. Acute infiltration of CD4(+) T cells in islets occurred with rapid onset of diabetes. Beta cells from islets with immune infiltration expressed MHC class II mRNA and protein. Exposure of beta cells to IFN-γ increased MHC class II gene expression, and blocking IFN-γ signaling in beta cells inhibited MHC class II upregulation. IFN-γ also increased HLA-DR expression in human islets. MHC class II(+) beta cells stimulated the proliferation of beta-cell-specific CD4(+) T cells. Our study indicates that MHC class II molecules may play an important role in beta-cell interaction with CD4(+) T cells in the development of type 1 diabetes.
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Affiliation(s)
- Yuxing Zhao
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia
| | - Nicholas A Scott
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - Hong Sheng Quah
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | | | - Francene Bond
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia
| | - Thomas Loudovaris
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia
| | - Stuart I Mannering
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - Thomas W H Kay
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - Helen E Thomas
- St. Vincent's Institute, Immunology and Diabetes Laboratory, Fitzroy, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
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23
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Zhao Y, Scott NA, Fynch S, Elkerbout L, Wong WWL, Mason KD, Strasser A, Huang DC, Kay TWH, Thomas HE. Autoreactive T cells induce necrosis and not BCL-2-regulated or death receptor-mediated apoptosis or RIPK3-dependent necroptosis of transplanted islets in a mouse model of type 1 diabetes. Diabetologia 2015; 58:140-8. [PMID: 25301392 DOI: 10.1007/s00125-014-3407-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/17/2014] [Indexed: 12/12/2022]
Abstract
AIMS/HYPOTHESIS Type 1 diabetes results from T cell-mediated destruction of pancreatic beta cells. The mechanisms of beta cell destruction in vivo, however, remain unclear. We aimed to test the relative roles of the main cell death pathways: apoptosis, necrosis and necroptosis, in beta cell death in the development of CD4(+) T cell-mediated autoimmune diabetes. METHODS We altered expression levels of critical cell death proteins in mouse islets and tested their ability to survive CD4(+) T cell-mediated attack using an in vivo graft model. RESULTS Loss of the B cell leukaemia/lymphoma 2 (BCL-2) homology domain 3-only proteins BIM, PUMA or BID did not protect beta cells from this death. Overexpression of the anti-apoptotic protein BCL-2 or combined deficiency of the pro-apoptotic multi-BCL2 homology domain proteins BAX and BAK also failed to prevent beta cell destruction. Furthermore, loss of function of the death receptor Fas or its essential downstream signalling molecule Fas-associated death domain (FADD) in islets was also not protective. Using electron microscopy we observed that dying beta cells showed features of necrosis. However, islets deficient in receptor-interacting serine/threonine protein kinase 3 (RIPK3), a critical initiator of necroptosis, were still normally susceptible to CD4(+) T cell-mediated destruction. Remarkably, simultaneous inhibition of apoptosis and necroptosis by combining loss of RIPK3 and overexpression of BCL-2 in islets did not protect them against immune attack either. CONCLUSIONS/INTERPRETATION Collectively, our data indicate that beta cells die by necrosis in autoimmune diabetes and that the programmed cell death pathways apoptosis and necroptosis are both dispensable for this process.
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MESH Headings
- Animals
- Apoptosis/genetics
- Apoptosis/physiology
- Autoimmunity/physiology
- Diabetes Mellitus, Experimental/immunology
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Graft Rejection/genetics
- Graft Rejection/immunology
- Graft Rejection/metabolism
- Islets of Langerhans/immunology
- Islets of Langerhans/metabolism
- Islets of Langerhans/pathology
- Islets of Langerhans Transplantation/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred NOD
- Mice, Transgenic
- Necrosis/genetics
- Necrosis/immunology
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/physiology
- Receptor-Interacting Protein Serine-Threonine Kinases/genetics
- Receptor-Interacting Protein Serine-Threonine Kinases/physiology
- Receptors, Death Domain/genetics
- Receptors, Death Domain/physiology
- T-Lymphocytes/immunology
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Affiliation(s)
- Yuxing Zhao
- St Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Melbourne, VIC, 3065, Australia
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24
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Wali JA, Trivedi P, Kay TW, Thomas HE. Measuring death of pancreatic beta cells in response to stress and cytotoxic T cells. Methods Mol Biol 2015; 1292:165-176. [PMID: 25804755 DOI: 10.1007/978-1-4939-2522-3_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Apoptosis of pancreatic beta cells is a feature of type 1 and type 2 diabetes, although by different effector mechanisms. In type 1 diabetes, beta cells are the targets of cytotoxic CD8(+) T cells that kill by releasing the contents of their cytotoxic granules into the immunological synapse with the target beta cell. In type 2 diabetes, the mechanisms of beta cell apoptosis are less clear, but believed to be due to cellular stresses including endoplasmic reticulum stress and oxidative stress induced by chronic exposure to high concentrations of glucose, lipids, inflammatory cytokines, or islet amyloid polypeptide. Measuring apoptosis in primary islets can be more difficult than in a beta cell line because islets exist as a cluster of cells and it is often difficult to obtain sufficient cells for any particular type of assay. Here, we describe two different methods for measuring islet cell apoptosis. The first method is the measurement of DNA fragmentation, a hallmark of apoptosis, of islets that have been cultured with reagents that induce stress. The second method is the measurement of islet lysis by activated cytotoxic T cells. We describe methods using mouse islets, but these can easily be adapted for human islets.
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Affiliation(s)
- Jibran A Wali
- St Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, VIC, 3065, Australia
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25
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Blake R, Trounce IA. Mitochondrial dysfunction and complications associated with diabetes. Biochim Biophys Acta Gen Subj 2014; 1840:1404-12. [DOI: 10.1016/j.bbagen.2013.11.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 10/18/2013] [Accepted: 11/06/2013] [Indexed: 02/06/2023]
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26
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Principe DR, Doll JA, Bauer J, Jung B, Munshi HG, Bartholin L, Pasche B, Lee C, Grippo PJ. TGF-β: duality of function between tumor prevention and carcinogenesis. J Natl Cancer Inst 2014; 106:djt369. [PMID: 24511106 DOI: 10.1093/jnci/djt369] [Citation(s) in RCA: 392] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Several mechanisms underlying tumor progression have remained elusive, particularly in relation to transforming growth factor beta (TGF-β). Although TGF-β initially inhibits epithelial growth, it appears to promote the progression of advanced tumors. Defects in normal TGF-β pathways partially explain this paradox, which can lead to a cascade of downstream events that drive multiple oncogenic pathways, manifesting as several key features of tumorigenesis (uncontrolled proliferation, loss of apoptosis, epithelial-to-mesenchymal transition, sustained angiogenesis, evasion of immune surveillance, and metastasis). Understanding the mechanisms of TGF-β dysregulation will likely reveal novel points of convergence between TGF-β and other pathways that can be specifically targeted for therapy.
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Affiliation(s)
- Daniel R Principe
- Affiliations of authors: Department of Medicine, Division of Gastroenterology (DRP, JB, BJ) and Division of Hematology/Oncology (HGM), Department of Surgery, Division of GI Surgical Oncology (DRP, PJG), and Department of Urology (CL), Northwestern University Feinberg School of Medicine, Chicago, IL; Department of Biomedical Engineering. McCormick School of Engineering, Northwestern University, Evanston, IL (DRP); Department of Biomedical Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI (JAD); UMR INSERM U1052, CNRS 5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France (LB); Division of Hematology/Oncology, Department of Medicine, University of Alabama-Birmingham, Birmingham, AL (BP); Department of Pathology and Laboratory Medicine, University of California-Irvine, Irvine, CA (CL)
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27
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SOCS and diabetes-ups and downs of a turbulent relationship. Cell Biochem Funct 2013; 31:181-95. [DOI: 10.1002/cbf.2940] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 11/10/2012] [Accepted: 11/16/2012] [Indexed: 11/07/2022]
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28
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Padgett LE, Broniowska KA, Hansen PA, Corbett JA, Tse HM. The role of reactive oxygen species and proinflammatory cytokines in type 1 diabetes pathogenesis. Ann N Y Acad Sci 2013; 1281:16-35. [PMID: 23323860 PMCID: PMC3715103 DOI: 10.1111/j.1749-6632.2012.06826.x] [Citation(s) in RCA: 201] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Type 1 diabetes (T1D) is a T cell–mediated autoimmune disease characterized by the destruction of insulin-secreting pancreatic β cells. In humans with T1D and in nonobese diabetic (NOD) mice (a murine model for human T1D), autoreactive T cells cause β-cell destruction, as transfer or deletion of these cells induces or prevents disease, respectively. CD4+ and CD8+ T cells use distinct effector mechanisms and act at different stages throughout T1D to fuel pancreatic β-cell destruction and disease pathogenesis. While these adaptive immune cells employ distinct mechanisms for β-cell destruction, one central means for enhancing their autoreactivity is by the secretion of proinflammatory cytokines, such as IFN-γ, TNF-α, and IL-1. In addition to their production by diabetogenic T cells, proinflammatory cytokines are induced by reactive oxygen species (ROS) via redox-dependent signaling pathways. Highly reactive molecules, proinflammatory cytokines are produced upon lymphocyte infiltration into pancreatic islets and induce disease pathogenicity by directly killing β cells, which characteristically possess low levels of antioxidant defense enzymes. In addition to β-cell destruction, proinflammatory cytokines are necessary for efficient adaptive immune maturation, and in the context of T1D they exacerbate autoimmunity by intensifying adaptive immune responses. The first half of this review discusses the mechanisms by which autoreactive T cells induce T1D pathogenesis and the importance of ROS for efficient adaptive immune activation, which, in the context of T1D, exacerbates autoimmunity. The second half provides a comprehensive and detailed analysis of (1) the mechanisms by which cytokines such as IL-1 and IFN-γ influence islet insulin secretion and apoptosis and (2) the key free radicals and transcription factors that control these processes.
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Affiliation(s)
- Lindsey E Padgett
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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29
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Graham KL, Sutherland RM, Mannering SI, Zhao Y, Chee J, Krishnamurthy B, Thomas HE, Lew AM, Kay TWH. Pathogenic mechanisms in type 1 diabetes: the islet is both target and driver of disease. Rev Diabet Stud 2012; 9:148-68. [PMID: 23804258 DOI: 10.1900/rds.2012.9.148] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Recent advances in our understanding of the pathogenesis of type 1 diabetes have occurred in all steps of the disease. This review outlines the pathogenic mechanisms utilized by the immune system to mediate destruction of the pancreatic beta-cells. The autoimmune response against beta-cells appears to begin in the pancreatic lymph node where T cells, which have escaped negative selection in the thymus, first meet beta-cell antigens presented by dendritic cells. Proinsulin is an important antigen in early diabetes. T cells migrate to the islets via the circulation and establish insulitis initially around the islets. T cells within insulitis are specific for islet antigens rather than bystanders. Pathogenic CD4⁺ T cells may recognize peptides from proinsulin which are produced locally within the islet. CD8⁺ T cells differentiate into effector T cells in islets and then kill beta-cells, primarily via the perforin-granzyme pathway. Cytokines do not appear to be important cytotoxic molecules in vivo. Maturation of the immune response within the islet is now understood to contribute to diabetes, and highlights the islet as both driver and target of the disease. The majority of our knowledge of these pathogenic processes is derived from the NOD mouse model, although some processes are mirrored in the human disease. However, more work is required to translate the data from the NOD mouse to our understanding of human diabetes pathogenesis. New technology, especially MHC tetramers and modern imaging, will enhance our understanding of the pathogenic mechanisms.
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Affiliation(s)
- Kate L Graham
- St. Vincent´s Institute of Medical Research, Fitzroy, Victoria, Australia
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30
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Varanasi V, Avanesyan L, Schumann DM, Chervonsky AV. Cytotoxic mechanisms employed by mouse T cells to destroy pancreatic β-cells. Diabetes 2012; 61:2862-70. [PMID: 22773667 PMCID: PMC3478530 DOI: 10.2337/db11-1784] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 05/01/2012] [Indexed: 12/21/2022]
Abstract
Several cytotoxic mechanisms have been attributed to T cells participating in β-cell death in type 1 diabetes. However, sensitivity of β-cells to these mechanisms in vitro and in vivo is likely to be different. Moreover, CD4⁺ and CD8⁺ T cells may use distinct mechanisms to cause β-cell demise that possibly involve activation of third-party cytotoxic cells. We used the transfer of genetically modified diabetogenic T cells into normal, mutant, and bone marrow chimeric recipients to test the contribution of major cytotoxic mechanisms in β-cell death. We found that 1) the killing of β-cells by CD4⁺ T cells required activation of the recipient's own cytotoxic cells via tumor necrosis factor-α (TNF-α); 2) CD8⁺ T-cell cytotoxic mechanisms destroying β-cells were limited to perforin and Fas ligand, as double knockouts of these molecules abrogated the ability of T cells to cause diabetes; and 3) individual CD8⁺ T-cell clones chose their cytotoxic weaponry by a yet unknown mechanism and destroyed their targets via either Fas-independent or Fas-dependent (~40% of clones) pathways. Fas-dependent destruction was assisted by TNF-α.
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MESH Headings
- Adoptive Transfer
- Animals
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/pathology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/pathology
- Cells, Cultured
- Clone Cells
- Cytotoxicity, Immunologic
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Fas Ligand Protein/genetics
- Fas Ligand Protein/metabolism
- Gene Expression Regulation
- Insulin-Secreting Cells/immunology
- Lymphocyte Activation
- Mice
- Mice, Inbred NOD
- Mice, Knockout
- Mice, SCID
- Mice, Transgenic
- Pore Forming Cytotoxic Proteins/genetics
- Pore Forming Cytotoxic Proteins/metabolism
- RNA, Messenger/metabolism
- Signal Transduction
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- T-Lymphocytes, Cytotoxic/pathology
- Tumor Necrosis Factor-alpha/genetics
- Tumor Necrosis Factor-alpha/metabolism
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Affiliation(s)
- Vineeth Varanasi
- Department of Pathology, University of Chicago, Chicago, Illinois
| | - Lia Avanesyan
- Department of Pathology, University of Chicago, Chicago, Illinois
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31
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Mollah ZU, Graham KL, Krishnamurthy B, Trivedi P, Brodnicki TC, Trapani JA, Kay TW, Thomas HE. Granzyme B is dispensable in the development of diabetes in non-obese diabetic mice. PLoS One 2012; 7:e40357. [PMID: 22792290 PMCID: PMC3392222 DOI: 10.1371/journal.pone.0040357] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 06/04/2012] [Indexed: 11/18/2022] Open
Abstract
Pancreatic beta cell destruction in type 1 diabetes is mediated by cytotoxic CD8(+) T lymphoctyes (CTL). Granzyme B is an effector molecule used by CTL to kill target cells. We previously showed that granzyme B-deficient allogeneic CTL inefficiently killed pancreatic islets in vitro. We generated granzyme B-deficient non-obese diabetic (NOD) mice to test whether granzyme B is an important effector molecule in spontaneous type 1 diabetes. Granzyme B-deficient islet antigen-specific CD8(+) T cells had impaired homing into islets of young mice. Insulitis was reduced in granzyme B-deficient mice at 70 days of age (insulitis score 0.043±0.019 in granzyme B-deficient versus 0.139±0.034 in wild-type NOD mice p<0.05), but was similar to wild-type at 100 and 150 days of age. We observed a reduced frequency of CD3(+)CD8(+) T cells in the islets and peripheral lymphoid tissues of granzyme B-deficient mice (p<0.005 and p<0.0001 respectively), but there was no difference in cell proportions in the thymus. Antigen-specific CTL developed normally in granzyme B-deficient mice, and were able to kill NOD islet target cells as efficiently as wild-type CTL in vitro. The incidence of spontaneous diabetes in granzyme B-deficient mice was the same as wild-type NOD mice. We observed a delayed onset of diabetes in granzyme B-deficient CD8-dependent NOD8.3 mice (median onset 102.5 days in granzyme B-deficient versus 57.50 days in wild-type NOD8.3 mice), which may be due to the delayed onset of insulitis or inefficient priming at an earlier age in this accelerated model of diabetes. Our data indicate that granzyme B is dispensable for beta cell destruction in type 1 diabetes, but is required for efficient early activation of CTL.
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Affiliation(s)
- Zia U. Mollah
- St. Vincent’s Institute, Fitzroy, Victoria, Australia
| | | | | | - Prerak Trivedi
- St. Vincent’s Institute, Fitzroy, Victoria, Australia
- Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Victoria, Australia
| | - Thomas C. Brodnicki
- St. Vincent’s Institute, Fitzroy, Victoria, Australia
- Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Victoria, Australia
| | | | - Thomas W. Kay
- St. Vincent’s Institute, Fitzroy, Victoria, Australia
- Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Victoria, Australia
| | - Helen E. Thomas
- St. Vincent’s Institute, Fitzroy, Victoria, Australia
- Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Victoria, Australia
- * E-mail:
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32
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Zhao F, Wang Q. The protective effect of peroxiredoxin II on oxidative stress induced apoptosis in pancreatic β-cells. Cell Biosci 2012; 2:22. [PMID: 22709359 PMCID: PMC3461449 DOI: 10.1186/2045-3701-2-22] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 06/18/2012] [Indexed: 01/11/2023] Open
Abstract
Excessive loss of pancreatic β-cells, mainly through apoptosis, contributes to the development of diabetic hyperglycemia. Oxidative stress plays a major role in the process of β-cell apoptosis due to low expression level of endogenous antioxidants in the β-cells. Peroxiredoxins (PRDX) are a family of peroxide reductases which uses thioredoxin to clear peroxides. Several members of PRDX have been found in β-cells and recent studies suggested that these antioxidant enzymes possess protective effects in β-cells against oxidative stress mediated apoptosis. In this study, we aimed to investigate the role of PRDX2 in modulating β-cell functions. We detected the expression of PRDX2 both at the transcript and protein levels in the clonal β-cells INS-1 and MIN6 as well as rodent islets. Western blot showed that treatment of MIN6 β-cell line with proinflammatory cytokines, palmitic acid or streptozotocin dose- or time-dependently increased apoptosis, which was associated with reduced endogenous expression levels of PRDX2. To examine the role for PRDX2 in the apoptotic stimuli-induced β-cell apoptosis, we used plasmid overexpression and siRNA knockdown strategies to investigate whether the elevation or knockdown of PRDX2 affects stimuli-induced apoptosis in the β-cells. Remarkably, overexpression of PRDX2 in MIN6 cells significantly attenuated the oxidative stresses mediated apoptosis, as evaluated by cleaved caspase 3 expression, nuclear condensation and fragmentation, as well as FACS analysis. Conversely, attenuation of PRDX2 protein expression using siRNA knockdown exaggerated the cell death induced by proinflammatory cytokines and palmitic acid in the MIN6 cells. These results suggest that PRDX2 may play a protective role in pancreatic β-cells under oxidative stress.
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Affiliation(s)
- Fang Zhao
- Division of Endocrinology and Metabolism, the Keenan Research Centre in the Li Ka Shing Knowledge Institute, St, Michael's Hospital, 209 Victoria Street, Room 414, Toronto, ON, Canada, M5B 1T8.
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33
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Graham KL, Krishnamurthy B, Fynch S, Ayala-Perez R, Slattery RM, Santamaria P, Thomas HE, Kay TWH. Intra-islet proliferation of cytotoxic T lymphocytes contributes to insulitis progression. Eur J Immunol 2012; 42:1717-22. [DOI: 10.1002/eji.201242435] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 03/12/2012] [Accepted: 04/06/2012] [Indexed: 01/25/2023]
Affiliation(s)
| | | | - Stacey Fynch
- St. Vincent's Institute; Fitzroy; Victoria; Australia
| | | | - Robyn M. Slattery
- Department of Immunology; Faculty of Medicine; Nursing and Health Sciences; Monash University; The Alfred Hospital; Victoria; Australia
| | - Pere Santamaria
- Julia McFarlane Diabetes Research Centre and Department of Microbiology; Immunology and Infectious Disease; Faculty of Medicine, University of Calgary; Calgary; Alberta; Canada
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34
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Liu Z, Cort L, Eberwine R, Herrmann T, Leif JH, Greiner DL, Yahalom B, Blankenhorn EP, Mordes JP. Prevention of type 1 diabetes in the rat with an allele-specific anti-T-cell receptor antibody: Vβ13 as a therapeutic target and biomarker. Diabetes 2012; 61:1160-8. [PMID: 22368175 PMCID: PMC3331757 DOI: 10.2337/db11-0867] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In earlier studies of the Iddm14 diabetes susceptibility locus in the rat, we identified an allele of the T-cell receptor (TCR) β-chain, Tcrb-V13S1A1, as a candidate gene. To establish its importance, we treated susceptible rats with a depleting anti-rat Vβ13 monoclonal antibody and then exposed them to either polyinosinic:polycytidylic acid or a diabetogenic virus to induce diabetes. The overall frequency of diabetes in the controls was 74% (n = 50), compared with 17% (n = 30) in the anti-Vβ13-treated animals, with minimal islet pathology in nondiabetic treated animals. T cells isolated from islets on day 5 after starting induction showed a greater proportion of Vβ13(+) T cells than did peripheral lymph node T cells. Vβ13 transcripts recovered from day 5 islets revealed focused Jβ usage and less CDR3 diversity than did transcripts from peripheral Vβ13(+) T cells. CDR3 usage was not skewed in control Vβ16 CDR3 transcripts. Anti-rat Vβ13 antibody also prevented spontaneous diabetes in BBDP rats. The Iddm14 gene is likely to be Tcrb-V13, indicating that TCR β-chain usage is a determinant of susceptibility to autoimmune diabetes in rats. It may be possible to prevent autoimmune diabetes by targeting a limited element of the T-cell repertoire.
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MESH Headings
- Alleles
- Animals
- Antibodies, Monoclonal/therapeutic use
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/prevention & control
- Female
- Gene Expression Regulation
- Genetic Predisposition to Disease
- Genetic Testing
- Islets of Langerhans/cytology
- Islets of Langerhans/metabolism
- Male
- Poly I-C/toxicity
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
- T-Lymphocytes/physiology
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Affiliation(s)
- Zhijun Liu
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Laura Cort
- Department of Microbiology and Immunology, Center for Immunogenetics and Inflammatory Diseases, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Ryan Eberwine
- Department of Microbiology and Immunology, Center for Immunogenetics and Inflammatory Diseases, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Thomas Herrmann
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Jean H. Leif
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Dale L. Greiner
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Barak Yahalom
- Division of Research Development, Biomedical Research Models, Worcester, Massachusetts
| | - Elizabeth P. Blankenhorn
- Department of Microbiology and Immunology, Center for Immunogenetics and Inflammatory Diseases, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - John P. Mordes
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
- Corresponding author: John P. Mordes,
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35
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The pro-apoptotic BH3-only protein Bid is dispensable for development of insulitis and diabetes in the non-obese diabetic mouse. Apoptosis 2011; 16:822-30. [PMID: 21644000 DOI: 10.1007/s10495-011-0615-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Type 1 diabetes is caused by death of insulin-producing pancreatic beta cells. Beta-cell apoptosis induced by FasL may be important in type 1 diabetes in humans and in the non-obese diabetic (NOD) mouse model. Deficiency of the pro-apoptotic BH3-only molecule Bid protects beta cells from FasL-induced apoptosis in vitro. We aimed to test the requirement for Bid, and the significance of Bid-dependent FasL-induced beta-cell apoptosis in type 1 diabetes. We backcrossed Bid-deficient mice, produced by homologous recombination and thus without transgene overexpression, onto a NOD genetic background. Genome-wide single nucleotide polymorphism analysis demonstrated that diabetes-related genetic regions were NOD genotype. Transferred beta cell antigen-specific CD8+ T cells proliferated normally in the pancreatic lymph nodes of Bid-deficient mice. Moreover, Bid-deficient NOD mice developed type 1 diabetes and insulitis similarly to wild-type NOD mice. Our data indicate that beta-cell apoptosis in type 1 diabetes can proceed without Fas-induced killing mediated by the BH3-only protein Bid.
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36
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Abstract
BACKGROUND Apoptosis of β cells is a feature of type 1 diabetes. It is also increasingly recognized in type 2 diabetes and islet graft rejection. METHODS We have studied the intracellular pathways that regulate β-cell apoptosis in type 1 and 2 diabetes. We have examined the role of Bid, a pro-apoptotic member of the Bcl-2 family, using islets from mice deficient in Bid. We also studied the Bcl-2 family molecules involved in killing by using high concentrations of reducing sugars such as glucose or ribose. RESULTS We found that Bid-deficient islets are protected from recombinant human perforin and granzyme B, as well as from Fas-mediated killing. This makes Bid a target for protection of β cells from multiple insults relevant to type 1 diabetes. In contrast to granzyme B and death receptor signalling, we found that islets lacking Bim or Puma were protected from glucose toxicity. CONCLUSIONS Our data indicate that different stimuli activate different initiator molecules in the Bcl-2-regulated pathway in β cells.
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Affiliation(s)
- Helen E Thomas
- St Vincent's Institute of Medical Research, Department of Medicine, University of Melbourne, St Vincent's Hospital, Fitzroy, Melbourne, Victoria, Australia.
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37
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High glucose-induced apoptosis in human coronary artery endothelial cells involves up-regulation of death receptors. Cardiovasc Diabetol 2011; 10:73. [PMID: 21816064 PMCID: PMC3161855 DOI: 10.1186/1475-2840-10-73] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 08/04/2011] [Indexed: 11/24/2022] Open
Abstract
Background High glucose can induce apoptosis in vascular endothelial cells, which may contribute to the development of vascular complications in diabetes. We evaluated the role of the death receptor pathway of apoptotic signaling in high glucose-induced apoptosis in human coronary artery endothelial cells (HCAECs). Methods HCAECs were treated with media containing 5.6, 11.1, and 16.7 mM of glucose for 24 h in the presence or absence of tumor necrosis factor (TNF)-α. For detection of apoptosis, DNA fragmentation assay was used. HCAEC expression of death receptors were analyzed by the PCR and flow cytometry methods. Also, using immunohistochemical techniques, coronary expression of death receptors was assessed in streptozotocin-nicotinamide-induced type 2 diabetic mice. Results Exposure of HCAECs to high glucose resulted in a significant increase in TNF-R1 and Fas expression, compared with normal glucose. High glucose increased TNF-α production by HCAECs and exogenous TNF-α up-regulated TNF-R1 and Fas expression in HCAECs. High glucose-induced up-regulation of TNF-R1 and Fas expression was undetectable in the presence of TNF-α. Treatment with TNF-R1 neutralizing peptides significantly inhibited high glucose-induced endothelial cell apoptosis. Type 2 diabetic mice displayed appreciable expression of TNF-R1 and Fas in coronary vessels. Conclusions In association with increased TNF-α levels, the death receptors, TNF-R1 and Fas, are up-regulated in HCAECs under high glucose conditions, which could in turn play a role in high glucose-induced endothelial cell apoptosis.
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38
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Chen J, Grieshaber S, Mathews CE. Methods to assess beta cell death mediated by cytotoxic T lymphocytes. J Vis Exp 2011:2724. [PMID: 21712795 DOI: 10.3791/2724] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Type 1 diabetes (T1D) is a T cell mediated autoimmune disease. During the pathogenesis, patients become progressively more insulinopenic as insulin production is lost, presumably this results from the destruction of pancreatic beta cells by T cells. Understanding the mechanisms of beta cell death during the development of T1D will provide insights to generate an effective cure for this disease. Cell-mediated lymphocytotoxicity (CML) assays have historically used the radionuclide Chromium 51 ((51)Cr) to label target cells. These targets are then exposed to effector cells and the release of (51)Cr from target cells is read as an indication of lymphocyte-mediated cell death. Inhibitors of cell death result in decreased release of (51)Cr. As effector cells, we used an activated autoreactive clonal population of CD8(+) Cytotoxic T lymphocytes (CTL) isolated from a mouse stock transgenic for both the alpha and beta chains of the AI4 T cell receptor (TCR). Activated AI4 T cells were co-cultured with (51)Cr labeled target NIT cells for 16 hours, release of (51)Cr was recorded to calculate specific lysis Mitochondria participate in many important physiological events, such as energy production, regulation of signaling transduction, and apoptosis. The study of beta cell mitochondrial functional changes during the development of T1D is a novel area of research. Using the mitochondrial membrane potential dye Tetramethyl Rhodamine Methyl Ester (TMRM) and confocal microscopic live cell imaging, we monitored mitochondrial membrane potential over time in the beta cell line NIT-1. For imaging studies, effector AI4 T cells were labeled with the fluorescent nuclear staining dye Picogreen. NIT-1 cells and T cells were co-cultured in chambered coverglass and mounted on the microscope stage equipped with a live cell chamber, controlled at 37°C, with 5% CO(2;), and humidified. During these experiments images were taken of each cluster every 3 minutes for 400 minutes. Over a course of 400 minutes, we observed the dissipation of mitochondrial membrane potential in NIT-1 cell clusters where AI4 T cells were attached. In the simultaneous control experiment where NIT-1 cells were co-cultured with MHC mis-matched human lymphocyte Jurkat cells, mitochondrial membrane potential remained intact. This technique can be used to observe real-time changes in mitochondrial membrane potential in cells under attack of cytotoxic lymphocytes, cytokines, or other cytotoxic reagents.
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Affiliation(s)
- Jing Chen
- Department of Pathology, College of Medicine, University of Florida, USA
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Graham KL, Krishnamurthy B, Fynch S, Mollah ZU, Slattery R, Santamaria P, Kay TW, Thomas HE. Autoreactive cytotoxic T lymphocytes acquire higher expression of cytotoxic effector markers in the islets of NOD mice after priming in pancreatic lymph nodes. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 178:2716-25. [PMID: 21641394 PMCID: PMC3124028 DOI: 10.1016/j.ajpath.2011.02.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 02/03/2011] [Accepted: 02/16/2011] [Indexed: 01/02/2023]
Abstract
Cytotoxic T lymphocytes (CTLs) that cause type 1 diabetes are activated in draining lymph nodes and become concentrated as fully active CTLs in inflamed pancreatic islets. It is unclear whether CTL function is driven by signals received in the lymph node or also in the inflamed tissue. We studied whether the development of cytotoxicity requires further activation in islets. Autoreactive CTLs found in the islets of diabetes-prone NOD mice had acquired much higher expression of the cytotoxic effector markers granzyme B, interferon γ, and CD107a than had those in the pancreatic lymph node (PLN). Increased expression seemed to result from stimulation in the islet itself. T cells held up from migrating from the PLN by administration of the sphingosine-1-phosphate agonist FTY720 did not increase expression of cytotoxic molecules in the PLN. Stimulation did not require antigen presentation or cytokine secretion by the target β cells because it was not affected by the absence of class I major histocompatibility complex expression or by the overexpression of suppressor of cytokine signaling-1. Activation of CD40-expressing cells stimulated increased CTL function and β-cell destruction, suggesting that signals derived from CD40-expressing cells promote the acquisition of cytotoxicity in the islet environment. These data provide in vivo evidence that stimulation of cytotoxic effector molecule expression occurs in inflamed islets and is independent of β cells.
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Affiliation(s)
| | | | | | | | - Robyn Slattery
- Department of Immunology, Faculty of Medicine, Nursing and Health Sciences, Monash University, The Alfred Hospital, Melbourne, Australia
| | - Pere Santamaria
- Julia McFarlane Diabetes Research Centre and Department of Microbiology and Infectious Disease, University of Calgary Faculty of Medicine, Calgary, Alberta, Canada
| | - Thomas W. Kay
- St. Vincent's Institute, Fitzroy, Australia
- University of Melbourne Department of Medicine, St. Vincent's Hospital, Fitzroy, Australia
| | - Helen E. Thomas
- St. Vincent's Institute, Fitzroy, Australia
- University of Melbourne Department of Medicine, St. Vincent's Hospital, Fitzroy, Australia
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Angstetra E, Graham KL, Zhao Y, Irvin AE, Elkerbout L, Santamaria P, Slattery RM, Kay TW, Thomas HE. An indirect role for NK cells in a CD4(+) T-cell-dependent mouse model of type I diabetes. Immunol Cell Biol 2011; 90:243-7. [PMID: 21383770 DOI: 10.1038/icb.2011.16] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CD8(+) T cells kill pancreatic β-cells in a cell-cell contact-dependent mechanism in the non-obese diabetic mouse. CD4(+) T lymphocytes are also able to kill pancreatic β-cells, but they do not directly contact β-cells and may use another cell type as the actual cytotoxic cell. Natural killer (NK) cells could have this role but it is uncertain whether they are cytotoxic towards β-cells. Therefore, the requirement for NK cells in β-cell destruction in the CD4-dependent T-cell antigen receptor transgenic NOD4.1 mice was examined. NK cells failed to kill β-cells in vitro, even in the absence of major histocompatibility complex class I. We observed only 9.7±1.1% of islet infiltrating NK cells from NOD4.1 mice expressing the degranulation marker CD107a. Diabetogenic CD4(+) T cells transferred disease to NODscid.IL2Rγ(-/-) mice lacking NK cells, indicating that NK cells do not contribute to β-cell death in vitro or in vivo. However, depletion of NK cells reduced diabetes incidence in NOD4.1 mice, suggesting that NK cells may help to maintain the right environment for cytotoxicity of effector cells.
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Chen J, Gusdon AM, Piganelli J, Leiter EH, Mathews CE. mt-Nd2(a) Modifies resistance against autoimmune type 1 diabetes in NOD mice at the level of the pancreatic β-cell. Diabetes 2011; 60:355-9. [PMID: 20980458 PMCID: PMC3012193 DOI: 10.2337/db10-1241] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To investigate whether a single nucleotide polymorphism (SNP) in the mitochondrial gene for NADH dehydrogenase 2 (mt-Nd2) can modulate susceptibility to type 1 diabetes in NOD mice. RESEARCH DESIGN AND METHODS NOD/ShiLtJ mice conplastic for the alloxan resistant (ALR)/Lt-derived mt-Nd2(a) allele (NOD.mt(ALR)) were created and compared with standard NOD (carrying the mt-Nd2(c) allele) for susceptibility to spontaneous autoimmune diabetes, or to diabetes elicited by reciprocal adoptive splenic leukocyte transfers, as well as by adoptive transfer of diabetogenic T-cell clones. β-Cell lines derived from either the NOD (NIT-1) or the NOD.mt(ALR) (NIT-4) were also created to compare their susceptibility to cytolysis by diabetogenic CD8(+) T-cells in vitro. RESULTS NOD mice differing at this single SNP developed spontaneous or adoptively transferred diabetes at comparable rates and percentages. However, conplastic mice with the mt-Nd2(a) allele exhibited resistance to transfer of diabetes by the CD4(+) T-cell clone BDC 2.5 as well as the CD8(+) AI4 T-cell clones from T-cell receptor transgenic animals. NIT-4 cells with mt-Nd2(a) were also more resistant to AI4-mediated destruction in vitro than NIT-1 cells. CONCLUSIONS Conplastic introduction into NOD mice of a variant mt-Nd2 allele alone was not sufficient to prevent spontaneous autoimmune diabetes. Subtle nonhematopoietic type 1 diabetes resistance was observed during adoptive transfer experiments with T-cell clones. This study confirms that genetic polymorphisms in mitochondria can modulate β-cell sensitivity to autoimmune T-cell effectors.
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Affiliation(s)
- Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, Florida
| | - Aaron M. Gusdon
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, Florida
| | - Jon Piganelli
- Division of Immunogenetics, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania
| | | | - Clayton E. Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, Florida
- Corresponding author: Clayton E. Mathews,
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Riboulet-Chavey A, Diraison F, Siew LK, Wong FS, Rutter GA. AMP-activated protein kinase regulates glucagon secretion from mouse pancreatic alpha cells. Diabetologia 2011; 54:125-34. [PMID: 20938634 PMCID: PMC6101198 DOI: 10.1007/s00125-010-1929-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Accepted: 09/01/2010] [Indexed: 10/19/2022]
Abstract
AIM/HYPOTHESIS AMP-activated protein kinase (AMPK), encoded by Prkaa genes, is emerging as a key regulator of overall energy homeostasis and the control of insulin secretion and action. We sought here to investigate the role of AMPK in controlling glucagon secretion from pancreatic islet alpha cells. METHODS AMPK activity was modulated in vitro in clonal alphaTC1-9 cells and isolated mouse pancreatic islets using pharmacological agents and adenoviruses encoding constitutively active or dominant negative forms of AMPK. Glucagon secretion was measured during static incubation by radioimmunoassay. AMPK activity was assessed by both direct phosphotransfer assay and by western (immuno-)blotting of the phosphorylated AMPK α subunits and the downstream target acetyl-CoA carboxylase 1. Intracellular free [Ca²(+)] was measured using Fura-Red. RESULTS Increasing glucose concentrations strongly inhibited AMPK activity in clonal pancreatic alpha cells. Forced increases in AMPK activity in alphaTC1-9 cells, achieved through the use of pharmacological agents including metformin, phenformin and A-769662, or via adenoviral transduction, resulted in stimulation of glucagon secretion at both low and high glucose concentrations, whereas AMPK inactivation inhibited both [Ca²(+)](i) increases and glucagon secretion at low glucose. Transduction of isolated mouse islets with an adenovirus encoding AMPK-CA under the control of the preproglucagon promoter increased glucagon secretion selectively at elevated glucose concentrations. CONCLUSIONS/INTERPRETATION AMPK is strongly regulated by glucose in pancreatic alpha cells, and increases in AMPK activity are sufficient and necessary for the stimulation of glucagon release in vitro. Modulation of AMPK activity in alpha cells may therefore provide a novel approach to controlling blood glucose concentrations.
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Affiliation(s)
- Audrey Riboulet-Chavey
- Department of Cell Biology, Division of Medicine, Sir Alexander Fleming Building, Imperial College, London, Exhibition Road, London SW7 2AZ, UK
| | - Frédérique Diraison
- Department of Cell Biology, Division of Medicine, Sir Alexander Fleming Building, Imperial College, London, Exhibition Road, London SW7 2AZ, UK
| | - L. Khai Siew
- Dept. of Cellular & Molecular Medicine, University of Bristol, School of Medical Sciences, Bristol, BS8 1TD, UK
| | - F. Susan Wong
- Dept. of Cellular & Molecular Medicine, University of Bristol, School of Medical Sciences, Bristol, BS8 1TD, UK
| | - Guy A. Rutter
- Department of Cell Biology, Division of Medicine, Sir Alexander Fleming Building, Imperial College, London, Exhibition Road, London SW7 2AZ, UK
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Anton G, Peltecu G, Socolov D, Cornitescu F, Bleotu C, Sgarbura Z, Teleman S, Iliescu D, Botezatu A, Goia CD, Huica I, Anton AC. Type-specific human papillomavirus detection in cervical smears in Romania. APMIS 2010:1-19. [PMID: 21143521 PMCID: PMC3132448 DOI: 10.1111/j.1600-0463.2011.02765.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
To study type 1 diabetes (T1D), excellent animal models exist, both spontaneously diabetic and virus-induced. Based on knowledge from these, this review focuses on the environmental factors leading to T1D, concentrated into four areas which are: (1) The thymus-dependent immune system: T1D is a T cell driven disease and the beta cells are destroyed in an inflammatory insulitis process. Autoimmunity is breakdown of self-tolerance and the balance between regulator T cells and aggressive effector T cells is disturbed. Inhibition of the T cells (by e.g. anti-CD3 antibody or cyclosporine) will stop the T1D process, even if initiated by virus. Theoretically, the risk from immunotherapy elicits a higher frequency of malignancy. (2) The activity of the beta cells: Resting beta cells display less antigenicity and are less sensitive to immune destruction. Beta-cell rest can be induced by giving insulin externally in metabolic doses or by administering potassium-channel openers. Both procedures prevent T1D in animal models, whereas no good human data exist due to the risk of hypoglycemia. (3) NKT cells: According to the hygiene hypothesis, stimulation of NKT cells by non-pathogen microbes gives rise to less T cell reaction and less autoimmunity. Glycolipids presented by CD1 molecules are central in this stimulation. (4) Importance of the intestine and gliadin intake: Gluten-free diet dramatically inhibits T1D in animal models, and epidemiological data are supportive of such an effect in humans. The mechanisms include less subclinical intestinal inflammation and permeability, and changed composition of bacterial flora, which can also be obtained by intake of probiotics. Gluten-free diet is difficult to implement, and short-term intake has no effect. Regarding the onset of the T1D disease process, slow-acting enterovirus and gliadin deposits are speculated to be etiological in genetically susceptible individuals, followed by the mentioned four pathogenetic factors acting in concert. Neutralization of any one of these factors is capable of stopping T1D development, as lessons are learned from the animal models.
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Affiliation(s)
- Gabriela Anton
- "Stefan S. Nicolau" Institute of Virology, Bucharest, Romania.
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Kondos SC, Hatfaludi T, Voskoboinik I, Trapani JA, Law RHP, Whisstock JC, Dunstone MA. The structure and function of mammalian membrane-attack complex/perforin-like proteins. ACTA ACUST UNITED AC 2010; 76:341-51. [PMID: 20860583 DOI: 10.1111/j.1399-0039.2010.01566.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The membrane-attack complex (MAC) of complement pathway and perforin (PF) are important tools deployed by the immune system to target pathogens. Both perforin and the C9 component of the MAC contain a common 'MACPF' domain and form pores in the cell membrane as part of their function. The MAC targets gram-negative bacteria and certain pathogenic parasites, while perforin, released by natural killer cells or cytotoxic T lymphocytes (CTLs), targets virus-infected and transformed host cells (1). Remarkably, recent structural studies show that the MACPF domain is homologous to the pore-forming portion of bacterial cholesterol-dependent cytolysins; these data have provided important insight into the mechanism of pore-forming MACPF proteins. In addition to their role in immunity, MACPF family members have been identified as animal venoms, factors required for pathogen migration across host cell membranes and factors that govern developmental processes such as embryonic patterning and neuronal guidance (2). While most MACPF proteins characterized to date either form pores or span lipid membranes, some do not (e.g. the C6 component of the MAC). A current challenge is thus to understand the role, pore forming or otherwise, of MACPF proteins in developmental biology. This review discusses structural and functional diversity of the mammalian MACPF proteins.
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Affiliation(s)
- S C Kondos
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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Voskoboinik I, Dunstone MA, Baran K, Whisstock JC, Trapani JA. Perforin: structure, function, and role in human immunopathology. Immunol Rev 2010; 235:35-54. [PMID: 20536554 DOI: 10.1111/j.0105-2896.2010.00896.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The secretory granule-mediated cell death pathway is the key mechanism for elimination of virus-infected and transformed target cells by cytotoxic lymphocytes. The formation of the immunological synapse between an effector and a target cell leads to exocytic trafficking of the secretory granules and the release of their contents, which include pro-apoptotic serine proteases, granzymes, and pore-forming perforin into the synapse. There, perforin polymerizes and forms a transmembrane pore that allows the delivery of granzymes into the cytosol, where they initiate various apoptotic death pathways. Unlike relatively redundant individual granzymes, functional perforin is absolutely essential for cytotoxic lymphocyte function and immune regulation in the host. Nevertheless, perforin is still the least studied and understood cytotoxic molecule in the immune system. In this review, we discuss the current state of affairs in the perforin field: the protein's structure and function as well as its role in immune-mediated diseases.
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Affiliation(s)
- Ilia Voskoboinik
- Cancer Cell Death Laboratory, Peter MacCallum Cancer Centre, East Melbourne, Vic. 8006, Australia
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Abstract
Apoptosis of beta cells is a feature of both type 1 and type 2 diabetes as well as loss of islets after transplantation. In type 1 diabetes, beta cells are destroyed by immunological mechanisms. In type 2 diabetes abnormal levels of metabolic factors contribute to beta cell failure and subsequent apoptosis. Loss of beta cells after islet transplantation is due to many factors including the stress associated with islet isolation, primary graft non-function and allogeneic graft rejection. Irrespective of the exact mediators, highly conserved intracellular pathways of apoptosis are triggered. This review will outline the molecular mediators of beta cell apoptosis and the intracellular pathways activated.
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Affiliation(s)
- Helen E Thomas
- St. Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, VIC 3065, Australia.
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Adenovirus E3 MHC inhibitory genes but not TNF/Fas apoptotic inhibitory genes expressed in beta cells prevent autoimmune diabetes. Proc Natl Acad Sci U S A 2009; 106:19450-4. [PMID: 19887639 DOI: 10.1073/pnas.0910648106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
To mimic events and molecules involved in type 1 insulin-dependent diabetes mellitus (T1D), we previously designed a transgenic (tg) mouse model where the viral nucleoprotein (NP) gene of lymphocytic choriomeningitis virus (LCMV) was expressed in the thymus to delete high affinity antiself (virus) T cells and in insulin-producing beta cells of the islets of Langerhans. Such tg mice, termed RIP-LCMV, fail to spontaneously develop diabetes. In contrast, when these mice are challenged with LCMV, they develop diabetes as they display hyperglycemia, low to absent levels of pancreatic insulin, and abundant mononuclear cell infiltrates in the islets. However, expressing the adenovirus early region (E3) gene in beta cells along with the LCMV transgene aborted the T1D. The present study utilizes this combined tg model (RIP LCMV x RIP E3) to define the requirement(s) of either pro-apoptotic TNF and Fas pathways or MHC class I up-regulation on beta cells for virus-induced T1D. Inhibitors to either pathway (TNF/Fas or MHC class I) are encoded in the E3 gene complex. To accomplish this task either the E3 region encoding the inhibitors of TNF and Fas pathways or the region encoding gp-19, a protein that inhibits transport of MHC class I molecules out of the endoplasmic reticulum were deleted in the RIP LCMV x RIP E3 model. Thus only the gp-19 is required to abort the virus-induced T1D. In contrast, removal of TNF- and Fas-pathway inhibitory genes had no effect on E3-mediated prevention of T1D.
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Gysemans C, Callewaert H, Moore F, Nelson-Holte M, Overbergh L, Eizirik DL, Mathieu C. Interferon regulatory factor-1 is a key transcription factor in murine beta cells under immune attack. Diabetologia 2009; 52:2374-2384. [PMID: 19756487 DOI: 10.1007/s00125-009-1514-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Accepted: 07/30/2009] [Indexed: 10/20/2022]
Abstract
AIMS/HYPOTHESIS IFN-gamma, together with other inflammatory cytokines such as IL-1beta and TNF-alpha, contributes to beta cell death in type 1 diabetes. We analysed the role of the transcription factor interferon regulatory factor (IRF)-1, a downstream target of IFN-gamma/signal transducer and activator of transcription (STAT)-1, in immune-mediated beta cell destruction. METHODS Islets from mice lacking Irf-1 (Irf-1 (-/-)) and control C57BL/6 mice were transplanted in overtly diabetic NOD mice. Viability and functionality of islets were evaluated in vitro. Chemokine expression by Irf-1 (-/-) islets and INS-1E cells transfected with Irf-1 short interfering RNA (siRNA) was measured by real-time PCR as well as in functional assays in vitro. RESULTS IRF-1 deletion in islets was associated with higher prevalence of primary non-function (63% vs 25%, p <or= 0.05) and shorter functioning graft survival (6.0 +/- 2.6 vs 10.4 +/- 4.8 days, p <or= 0.05) in contrast to similar skin graft survival. Although Irf-1 (-/-) islets were resistant to cytokine-induced cell death, insulin secretion by them was lower than that of control C57BL/6 islets under medium and cytokine conditions. IL-1 receptor antagonist partly restored the cytokine-induced secretory defect in vitro and completely prevented primary non-function in vivo. Cytokine-exposed Irf-1 (-/-) islets and INS-1E cells transfected with Irf-1 siRNA showed increased expression of Mcp-1 (also known as Ccl2), Ip-10 (also known as Cxcl10), Mip-3alpha (also known as Ccl20) and Inos (also known as Nos2) mRNA and elevated production of monocyte chemoattractant protein-1 (MCP-1) and nitrite compared with controls. In vivo, Irf-1 (-/-) islets displayed a higher potential to attract immune cells, reflected by more aggressive immune infiltration in the grafted islets. CONCLUSIONS/INTERPRETATION These data indicate a key regulatory role for IRF-1 in insulin and chemokine secretion by pancreatic islets under inflammatory attack.
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Affiliation(s)
- C Gysemans
- LEGENDO, Campus Gasthuisberg O&N1, Herestraat 49, bus 902, 3000, Leuven, Belgium
| | - H Callewaert
- LEGENDO, Campus Gasthuisberg O&N1, Herestraat 49, bus 902, 3000, Leuven, Belgium
| | - F Moore
- Laboratory of Experimental Medicine, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - M Nelson-Holte
- LEGENDO, Campus Gasthuisberg O&N1, Herestraat 49, bus 902, 3000, Leuven, Belgium
| | - L Overbergh
- LEGENDO, Campus Gasthuisberg O&N1, Herestraat 49, bus 902, 3000, Leuven, Belgium
| | - D L Eizirik
- Laboratory of Experimental Medicine, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - C Mathieu
- LEGENDO, Campus Gasthuisberg O&N1, Herestraat 49, bus 902, 3000, Leuven, Belgium.
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Rasche S, Busick RY, Quinn A. GAD65-Specific Cytotoxic T Lymphocytes Mediate Beta-Cell Death and Loss of Function. Rev Diabet Stud 2009; 6:43-53. [PMID: 19557295 DOI: 10.1900/rds.2009.6.43] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Autoimmunity to islet cell antigens like glutamic acid decarboxylase 65kD (GAD65) is associated with the destruction of insulin-producing beta-cells and progression to type 1 diabetes (T1D) in NOD mice and humans. T cell responses to GAD65 are detectable in the spleen of prediabetic NOD mice and in the peripheral blood of humans prior to the onset of overt hyperglycemia. Previous findings from our lab revealed that GAD65(546-554)-specific cytotoxic T lymphocytes (CTL) are present in naïve NOD mice and are able to induce islet inflammation upon adoptive transfer into NOD.scid recipients. Additionally, we found that professional antigen-presenting cells (APC) generate the p546-554 epitope from a soluble GAD65 fragment, p530-554, and from GAD65 released by injured beta-cells in vivo. Here, we report that the GAD65 fragment p546-554 is a dominant CTL-inducing epitope which is naturally processed and presented by a GAD65-expressing beta-cell line. Further, co-culture of GAD65(546-554)-specific CTL with the beta-cells leads to a reduction in insulin production and the induction of perforin-mediated cell death. Collectively, these findings support a role for the cross-presentation of GAD65 antigen in the priming and enhancement of dominant GAD65-specific CTL responses, which can directly target beta-cells that display GAD65 epitopes.
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Affiliation(s)
- Sarah Rasche
- Department of Biological Sciences, University of Toledo, 2801 W. Bancroft, Toledo, OH 43606, USA
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