1
|
Monti M, Ferrari G, Gazzurelli L, Bugatti M, Facchetti F, Vermi W. Plasmacytoid dendritic cells at the forefront of anti-cancer immunity: rewiring strategies for tumor microenvironment remodeling. J Exp Clin Cancer Res 2024; 43:196. [PMID: 39020402 PMCID: PMC11253500 DOI: 10.1186/s13046-024-03121-9] [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: 05/10/2024] [Accepted: 07/08/2024] [Indexed: 07/19/2024] Open
Abstract
Plasmacytoid dendritic cells (pDCs) are multifaceted immune cells executing various innate immunological functions. Their first line of defence consists in type I interferons (I-IFN) production upon nucleic acids sensing through endosomal Toll-like receptor (TLR) 7- and 9-dependent signalling pathways. Type I IFNs are a class of proinflammatory cytokines that have context-dependent functions on cancer immunosurveillance and immunoediting. In the last few years, different studies have reported that pDCs are also able to sense cytosolic DNA through cGAS-STING (stimulator of interferon genes) pathway eliciting a potent I-IFN production independently of TLR7/9. Human pDCs are also endowed with direct effector functions via the upregulation of TRAIL and production of granzyme B, the latter modulated by cytokines abundant in cancer tissues. pDCs have been detected in a wide variety of human malignant neoplasms, including virus-associated cancers, recruited by chemotactic stimuli. Although the role of pDCs in cancer immune surveillance is still uncompletely understood, their spontaneous activation has been rarely documented; moreover, their presence in the tumor microenvironment (TME) has been associated with a tolerogenic phenotype induced by immunosuppressive cytokines or oncometabolites. Currently tested treatment options can lead to pDCs activation and disruption of the immunosuppressive TME, providing a relevant clinical benefit. On the contrary, the antibody-drug conjugates targeting BDCA-2 on immunosuppressive tumor-associated pDCs (TA-pDCs) could be proposed as novel immunomodulatory therapies to achieve disease control in patients with advance stage hematologic malignancies or solid tumors. This Review integrate recent evidence on the biology of pDCs and their pharmacological modulation, suggesting their relevant role at the forefront of cancer immunity.
Collapse
Affiliation(s)
- Matilde Monti
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy
| | - Giorgia Ferrari
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy
| | - Luisa Gazzurelli
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy
| | - Mattia Bugatti
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy
| | - Fabio Facchetti
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy
| | - William Vermi
- Department of Molecular and Translational Medicine, Section of Pathology, University of Brescia, P.Le Spedali Civili 1, 25123, Brescia, Italy.
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA.
| |
Collapse
|
2
|
Naseri B, Mardi A, Khosrojerdi A, Baghbani E, Aghebati-Maleki L, Hatami-Sadr A, Heris JA, Eskandarzadeh S, Kafshdouz M, Alizadeh N, Baradaran B. Everolimus treatment enhances inhibitory immune checkpoint molecules' expression in monocyte-derived dendritic cells. Hum Immunol 2024; 85:110798. [PMID: 38569354 DOI: 10.1016/j.humimm.2024.110798] [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: 12/31/2023] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024]
Abstract
BACKGROUND Antigen-specific T-cell immunity is provided by dendritic cells (DCs), which are specialized antigen-presenting cells. Furthermore, they establish a link between innate and adaptive immune responses. Currently, DC modification is a new approach for the therapy of several disorders. During solid organ transplantation, Everolimus, which is a mammalian target of rapamycin (mTOR) inhibitor, was initially utilized to suppress the immune system's functionality. Due to the intervention of Everolimus in various signaling pathways in cells and its modulatory properties on the immune system, this study aims to investigate the effect of treatment with Everolimus on the maturation and expression of immune checkpoint genes in monocyte-derived DCs. METHODS To isolate monocytes from PBMCs, the CD14 marker was used via the MACS method. Monocytes were cultured and induced to differentiate into monocyte-derived DCs by utilizing GM-CSF and IL-4 cytokines. On the fifth day, immature DCs were treated with Everolimus and incubated for 24 h. On the sixth day, the flow cytometry technique was used to investigate the effect of Everolimus on the phenotypic characteristics of DCs. In the end, the expression of immune checkpoint genes in both the Everolimus-treated and untreated DCs groups was assessed using the real-time PCR method. RESULTS The findings of this research demonstrated that the administration of Everolimus to DCs led to a notable rise in human leukocyte antigen (HLA)-DR expression and a decrease in CD11c expression. Furthermore, there was a significant increase in the expression of immune checkpoint molecules, namely CTLA-4, VISTA, PD-L1, and BTLA, in DCs treated with Everolimus. CONCLUSION The findings of this study show that Everolimus can target DCs and affect their phenotype and function in order to shift them toward a partially tolerogenic state. However, additional research is required to gain a comprehensive understanding of the precise impact of Everolimus on the activation status of DCs.
Collapse
Affiliation(s)
- Bahar Naseri
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amirhossein Mardi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Arezou Khosrojerdi
- Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran
| | - Elham Baghbani
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | | | | | - Mahshid Kafshdouz
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nazila Alizadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behzad Baradaran
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
| |
Collapse
|
3
|
Menezes dos Reis L, Berçot MR, Castelucci BG, Martins AJE, Castro G, Moraes-Vieira PM. Immunometabolic Signature during Respiratory Viral Infection: A Potential Target for Host-Directed Therapies. Viruses 2023; 15:v15020525. [PMID: 36851739 PMCID: PMC9965666 DOI: 10.3390/v15020525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/05/2023] [Accepted: 02/06/2023] [Indexed: 02/16/2023] Open
Abstract
RNA viruses are known to induce a wide variety of respiratory tract illnesses, from simple colds to the latest coronavirus pandemic, causing effects on public health and the economy worldwide. Influenza virus (IV), parainfluenza virus (PIV), metapneumovirus (MPV), respiratory syncytial virus (RSV), rhinovirus (RhV), and coronavirus (CoV) are some of the most notable RNA viruses. Despite efforts, due to the high mutation rate, there are still no effective and scalable treatments that accompany the rapid emergence of new diseases associated with respiratory RNA viruses. Host-directed therapies have been applied to combat RNA virus infections by interfering with host cell factors that enhance the ability of immune cells to respond against those pathogens. The reprogramming of immune cell metabolism has recently emerged as a central mechanism in orchestrated immunity against respiratory viruses. Therefore, understanding the metabolic signature of immune cells during virus infection may be a promising tool for developing host-directed therapies. In this review, we revisit recent findings on the immunometabolic modulation in response to infection and discuss how these metabolic pathways may be used as targets for new therapies to combat illnesses caused by respiratory RNA viruses.
Collapse
Affiliation(s)
- Larissa Menezes dos Reis
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Marcelo Rodrigues Berçot
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-270, SP, Brazil
| | - Bianca Gazieri Castelucci
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Ana Julia Estumano Martins
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas, Campinas 13083-970, SP, Brazil
| | - Gisele Castro
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Pedro M. Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Experimental Medicine Research Cluster (EMRC), University of Campinas, Campinas 13083-872, SP, Brazil
- Obesity and Comorbidities Research Center (OCRC), University of Campinas, Campinas 13083-872, SP, Brazil
- Correspondence:
| |
Collapse
|
4
|
O'Shea AE, Valdera FA, Ensley D, Smolinsky TR, Cindass JL, Kemp Bohan PM, Hickerson AT, Carpenter EL, McCarthy PM, Adams AM, Vreeland TJ, Clifton GT, Peoples GE. Immunologic and dose dependent effects of rapamycin and its evolving role in chemoprevention. Clin Immunol 2022; 245:109095. [PMID: 35973640 DOI: 10.1016/j.clim.2022.109095] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 08/06/2022] [Indexed: 11/29/2022]
Abstract
Rapamycin inhibits the mechanistic (formally mammalian) target of rapamycin (mTOR), an evolutionarily conserved intracellular kinase that influences activation of growth signaling pathways and immune responses to malignancy. Rapamycin has been found to have both immunosuppressant and immunostimulatory effects throughout the innate and adaptive responses based on the inhibition of mTOR signaling. While the immunosuppressant properties of rapamycin and mTOR inhibition explain rapamycin's success in the prevention of transplant rejection, the immunostimulatory characteristics are likely partially responsible for rapamycin's anti-neoplastic effects. The immunologic response to rapamycin is at least partially dependent on the dose and administration schedule, with lower doses inducing immunostimulation and intermittent dosing promoting immune function while limiting metabolic and immunosuppressant toxicities. In addition to its FDA-approved application in advanced malignancies, rapamycin may be effective as a chemopreventive agent, suspending progression of low-grade cancers, preventing invasive conversion of in situ malignancy, or delaying malignant transformation of established pre-malignant conditions.
Collapse
Affiliation(s)
- Anne E O'Shea
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | - Franklin A Valdera
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA.
| | - Daniel Ensley
- Department of Urology, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | - Todd R Smolinsky
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | - Jessica L Cindass
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | | | | | | | - Patrick M McCarthy
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | - Alexandra M Adams
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA
| | - Timothy J Vreeland
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA; Department of Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | - Guy T Clifton
- Department of Surgery, Brooke Army Medical Center, Ft. Sam Houston, TX, USA; Department of Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | | |
Collapse
|
5
|
Sipka A, Weichhart T, Mann S. Pharmacological inhibition of the mTOR pathway alters phenotype and cytokine expression in bovine monocyte-derived dendritic cells. Vet Immunol Immunopathol 2022; 249:110441. [PMID: 35597229 DOI: 10.1016/j.vetimm.2022.110441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/05/2022] [Accepted: 05/13/2022] [Indexed: 01/20/2023]
Abstract
Epidemiological studies have long demonstrated the association of nutrient status and immune dysfunction in dairy cows. Postpartum dairy cows experiencing a nutrient deficit show a propensity for increased inflammatory response, decreased pathogen clearance, and increased incidence of infectious disease. Studies in cows and other species show that the nutrient sensing mechanistic target of rapamycin (mTOR) signaling pathway could be one potential causal pathway connecting the deficit in nutrient availability and the heightened inflammatory response. Our objective was to investigate the effects of pharmacological mTOR pathway inhibition on phenotype and cytokine expression of bovine monocyte derived dendritic cells (moDC). We differentiated CD14+ monocytes from dairy cows (n = 14) into moDC in the presence or absence of first- or second-generation mTOR inhibitor rapamycin and PP242 (both 100 nM), respectively. On day seven cells were matured with E. coli lipopolysaccharide (LPS, 100 ng/mL) or left unstimulated to represent naïve moDC. Surface expression of CD14, CD40, CD80, and MHCII was measured via flow cytometry. We measured mRNA expression of IL10, IL12A, IL12B, and TNFα by rt-qPCR, and protein concentrations of IL-10 and TFN-α in cell culture supernatants with a bead-based multiplex assay. Cultures from ten cows successfully developed the moDC phenotype in culture without inhibitors, defined as increased surface expression of CD40, CD80, and MHCII compared with naïve moDC. Only data from these cows were considered for the results on effects of mTOR inhibitors. In naïve and mature moDC mTOR inhibition increased MHCII expression compared to controls. In mature moDC, in addition to MHCII, CD80 expression was increased compared with untreated LPS-stimulated controls. Expression of IL12A mRNA was upregulated in mature, mTOR inhibited moDC compared with untreated controls. In cell culture supernatants mTOR inhibition reduced IL-10 and increased TNF-α concentrations in naïve and mature moDCs compared with untreated controls. Overall rapamycin had a more consistent effect on altering phenotype and cytokine expression of moDC than PP242. In summary we observed an increased expression of co-stimulatory molecules and antigen presentation potential in mature moDC differentiated under mTOR inhibition, and a cytokine pattern that would potentially favor a Th1 type response. This study provides novel data indicating a role for mTOR signaling in bovine moDC phenotype and mediator profile. This proof-of-concept study demonstrates the role of the mTOR pathway in shaping the bovine immune response and may help to provide mechanistic insight and opportunities for modulation of the immune response during the nutrient deficit of early lactation.
Collapse
Affiliation(s)
- Anja Sipka
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
| | - Thomas Weichhart
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, Währinger Straße 10, 1090 Vienna, Austria
| | - Sabine Mann
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| |
Collapse
|
6
|
Tomalka JA, Suthar MS, Deeks SG, Sekaly RP. Fighting the SARS-CoV-2 pandemic requires a global approach to understanding the heterogeneity of vaccine responses. Nat Immunol 2022; 23:360-370. [PMID: 35210622 DOI: 10.1038/s41590-022-01130-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 01/05/2022] [Indexed: 11/09/2022]
Abstract
Host genetic and environmental factors including age, biological sex, diet, geographical location, microbiome composition and metabolites converge to influence innate and adaptive immune responses to vaccines. Failure to understand and account for these factors when investigating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine efficacy may impair the development of the next generation of vaccines. Most studies aimed at identifying mechanisms of vaccine-mediated immune protection have focused on adaptive immune responses. It is well established, however, that mobilization of the innate immune response is essential to the development of effective cellular and humoral immunity. A comprehensive understanding of the innate immune response and environmental factors that contribute to the development of broad and durable cellular and humoral immune responses to SARS-CoV-2 and other vaccines requires a holistic and unbiased approach. Along with optimization of the immunogen and vectors, the development of adjuvants based on our evolving understanding of how the innate immune system shapes vaccine responses will be essential. Defining the innate immune mechanisms underlying the establishment of long-lived plasma cells and memory T cells could lead to a universal vaccine for coronaviruses, a key biomedical priority.
Collapse
Affiliation(s)
- Jeffrey A Tomalka
- Pathology Advanced Translational Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Mehul S Suthar
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.,Department of Pediatrics, Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Steven G Deeks
- Department of Medicine, University of California at San Francisco School of Medicine, San Francisco, CA, USA
| | - Rafick Pierre Sekaly
- Pathology Advanced Translational Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA. .,Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.
| |
Collapse
|
7
|
Fu J, Lehmann CHK, Wang X, Wahlbuhl M, Allabauer I, Wilde B, Amon L, Dolff S, Cesnjevar R, Kribben A, Woelfle J, Rascher W, Hoyer PF, Dudziak D, Witzke O, Hoerning A. CXCR4 blockade reduces the severity of murine heart allograft rejection by plasmacytoid dendritic cell-mediated immune regulation. Sci Rep 2021; 11:23815. [PMID: 34893663 PMCID: PMC8664946 DOI: 10.1038/s41598-021-03115-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 11/08/2021] [Indexed: 12/20/2022] Open
Abstract
Allograft-specific regulatory T cells (Treg cells) are crucial for long-term graft acceptance after transplantation. Although adoptive Treg cell transfer has been proposed, major challenges include graft-specificity and stability. Thus, there is an unmet need for the direct induction of graft-specific Treg cells. We hypothesized a synergism of the immunotolerogenic effects of rapamycin (mTOR inhibition) and plerixafor (CXCR4 antagonist) for Treg cell induction. Thus, we performed fully-mismatched heart transplantations and found combination treatment to result in prolonged allograft survival. Moreover, fibrosis and myocyte lesions were reduced. Although less CD3+ T cell infiltrated, higher Treg cell numbers were observed. Noteworthy, this was accompanied by a plerixafor-dependent plasmacytoid dendritic cells-(pDCs)-mobilization. Furthermore, in vivo pDC-depletion abrogated the plerixafor-mediated Treg cell number increase and reduced allograft survival. Our pharmacological approach allowed to increase Treg cell numbers due to pDC-mediated immune regulation. Therefore pDCs can be an attractive immunotherapeutic target in addition to plerixafor treatment.
Collapse
Affiliation(s)
- Jian Fu
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.,Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany.,The Emergency and Trauma Center, The First Affiliated Hospital of Hai Nan Medical University, Haikou, China
| | - Christian H K Lehmann
- Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University of Erlangen-Nürnberg, Research Module II, Hartmannstr. 14, 91052, Erlangen, Germany. .,Medical Immunology Campus and German Centre for Immuntherapy (Deutsches Zentrum für Immuntherapie-DZI) Erlangen, FAU Erlangen-Nürnberg, 91054, Erlangen, Germany.
| | - Xinning Wang
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.,The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Mandy Wahlbuhl
- Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany
| | - Ida Allabauer
- Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany
| | - Benjamin Wilde
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Lukas Amon
- Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University of Erlangen-Nürnberg, Research Module II, Hartmannstr. 14, 91052, Erlangen, Germany
| | - Sebastian Dolff
- Department of Infectious Diseases, West German Centre of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, Essen, Germany
| | - Robert Cesnjevar
- Department of Pediatric Cardiac Surgery, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), University Hospital Erlangen, Erlangen, Germany.,Department of Cardiac Surgery, Universitäts-Kinderspital Zürich, Zurich, Switzerland
| | - Andreas Kribben
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Joachim Woelfle
- Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany
| | - Wolfgang Rascher
- Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany
| | - Peter F Hoyer
- Department of Pediatrics II, Pediatric Nephrology, Gastroenterology, Endocrinology and Transplant Medicine, Children's Hospital Essen, University Duisburg-Essen, Duisburg, Germany
| | - Diana Dudziak
- Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University of Erlangen-Nürnberg, Research Module II, Hartmannstr. 14, 91052, Erlangen, Germany.,Medical Immunology Campus and German Centre for Immuntherapy (Deutsches Zentrum für Immuntherapie-DZI) Erlangen, FAU Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Oliver Witzke
- Department of Infectious Diseases, West German Centre of Infectious Diseases, Universitätsmedizin Essen, University Duisburg-Essen, Essen, Germany
| | - André Hoerning
- Department for Pediatric and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Loschgestrasse 15, 91054, Erlangen, Germany. .,Department of Pediatrics II, Pediatric Nephrology, Gastroenterology, Endocrinology and Transplant Medicine, Children's Hospital Essen, University Duisburg-Essen, Duisburg, Germany.
| |
Collapse
|
8
|
Modulation of the mTOR pathway plays a central role in dendritic cell functions after Echinococcus granulosus antigen recognition. Sci Rep 2021; 11:17238. [PMID: 34446757 PMCID: PMC8390662 DOI: 10.1038/s41598-021-96435-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 07/09/2021] [Indexed: 12/12/2022] Open
Abstract
Immune evasion is a hallmark of persistent echinococcal infection, comprising modulation of innate immune cells and antigen-specific T cell responses. However, recognition of Echinococcus granulosus by dendritic cells (DCs) is a key determinant of the host's response to this parasite. Given that mTOR signaling pathway has been described as a regulator linking metabolism and immune function in DCs, we reported for the first time in these cells, global translation levels, antigen uptake, phenotype, cytokine transcriptional levels, and splenocyte priming activity upon recognition of the hydatid fluid (HF) and the highly glycosylated laminar layer (LL). We found that LL induced a slight up-regulation of CD86 and MHC II in DCs and also stimulated the production of IL-6 and TNF-α. By contrast, HF did not increase the expression of any co-stimulatory molecules, but also down-modulated CD40 and stimulated the expression of the anti-inflammatory cytokine IL-10. Both parasitic antigens promoted protein synthesis through mTOR activation. The use of rapamycin decreased the expression of the cytokines tested, empowered the down-modulation of CD40 and also reduced splenocyte proliferation. Finally, we showed that E. granulosus antigens increase the amounts of LC3-positive structures in DCs which play critical roles in the presentation of these antigens to T cells.
Collapse
|
9
|
Schnappauf O, Heale L, Dissanayake D, Tsai WL, Gadina M, Leto TL, Kastner DL, Malech HL, Kuhns DB, Aksentijevich I, Laxer RM. Homozygous variant p. Arg90His in NCF1 is associated with early-onset Interferonopathy: a case report. Pediatr Rheumatol Online J 2021; 19:54. [PMID: 33892719 PMCID: PMC8063424 DOI: 10.1186/s12969-021-00536-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/11/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Biallelic loss-of-function variants in NCF1 lead to reactive oxygen species deficiency and chronic granulomatous disease (CGD). Heterozygosity for the p.Arg90His variant in NCF1 has been associated with susceptibility to systemic lupus erythematosus, rheumatoid arthritis, and Sjögren's syndrome in adult patients. This study demonstrates the association of the homozygous p.Arg90His variant with interferonopathy with features of autoinflammation and autoimmunity in a pediatric patient. CASE PRESENTATION A 5-year old female of Indian ancestry with early-onset recurrent fever and headache, and persistently elevated antinuclear, anti-Ro, and anti-La antibodies was found to carry the homozygous p.Arg90His variant in NCF1 through exome sequencing. Her unaffected parents and three other siblings were carriers for the mutant allele. Because the presence of two NCF1 pseudogenes, this variant was confirmed by independent genotyping methods. Her intracellular neutrophil oxidative burst and NCF1 expression levels were normal, and no clinical features of CGD were apparent. Gene expression analysis in peripheral blood detected an interferon gene expression signature, which was further supported by cytokine analyses of supernatants of cultured patient's cells. These findings suggested that her inflammatory disease is at least in part mediated by type I interferons. While her fever episodes responded well to systemic steroids, treatment with the JAK inhibitor tofacitinib resulted in decreased serum ferritin levels and reduced frequency of fevers. CONCLUSION Homozygosity for p.Arg90His in NCF1 should be considered contributory in young patients with an atypical systemic inflammatory antecedent phenotype that may evolve into autoimmunity later in life. The complex genomic organization of NCF1 poses a difficulty for high-throughput genotyping techniques and variants in this gene should be carefully evaluated when using the next generation and Sanger sequencing technologies. The p.Arg90His variant is found at a variable allele frequency in different populations, and is higher in people of South East Asian ancestry. In complex genetic diseases such as SLE, other rare and common susceptibility alleles might be necessary for the full disease expressivity.
Collapse
Affiliation(s)
- Oskar Schnappauf
- National Human Genome Research Institute, National Institutes of Health, Bethesda, USA.
| | - Liane Heale
- grid.17063.330000 0001 2157 2938The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Dilan Dissanayake
- grid.17063.330000 0001 2157 2938The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Wanxia L. Tsai
- grid.94365.3d0000 0001 2297 5165National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, USA
| | - Massimo Gadina
- grid.94365.3d0000 0001 2297 5165National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, USA
| | - Thomas L. Leto
- grid.94365.3d0000 0001 2297 5165National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Daniel L. Kastner
- grid.94365.3d0000 0001 2297 5165National Human Genome Research Institute, National Institutes of Health, Bethesda, USA
| | - Harry L. Malech
- grid.94365.3d0000 0001 2297 5165National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Douglas B. Kuhns
- grid.418021.e0000 0004 0535 8394Frederick National Laboratory for Cancer Research, Frederick, USA
| | - Ivona Aksentijevich
- grid.94365.3d0000 0001 2297 5165National Human Genome Research Institute, National Institutes of Health, Bethesda, USA
| | - Ronald M. Laxer
- grid.17063.330000 0001 2157 2938The Hospital for Sick Children, University of Toronto, Toronto, Canada
| |
Collapse
|
10
|
Bencze D, Fekete T, Pázmándi K. Type I Interferon Production of Plasmacytoid Dendritic Cells under Control. Int J Mol Sci 2021; 22:ijms22084190. [PMID: 33919546 PMCID: PMC8072550 DOI: 10.3390/ijms22084190] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/11/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022] Open
Abstract
One of the most powerful and multifaceted cytokines produced by immune cells are type I interferons (IFNs), the basal secretion of which contributes to the maintenance of immune homeostasis, while their activation-induced production is essential to effective immune responses. Although, each cell is capable of producing type I IFNs, plasmacytoid dendritic cells (pDCs) possess a unique ability to rapidly produce large amounts of them. Importantly, type I IFNs have a prominent role in the pathomechanism of various pDC-associated diseases. Deficiency in type I IFN production increases the risk of more severe viral infections and the development of certain allergic reactions, and supports tumor resistance; nevertheless, its overproduction promotes autoimmune reactions. Therefore, the tight regulation of type I IFN responses of pDCs is essential to maintain an adequate level of immune response without causing adverse effects. Here, our goal was to summarize those endogenous factors that can influence the type I IFN responses of pDCs, and thus might serve as possible therapeutic targets in pDC-associated diseases. Furthermore, we briefly discuss the current therapeutic approaches targeting the pDC-type I IFN axis in viral infections, cancer, autoimmunity, and allergy, together with their limitations defined by the Janus-faced nature of pDC-derived type I IFNs.
Collapse
Affiliation(s)
- Dóra Bencze
- Department of Immunology, Faculty of Medicine, University of Debrecen, 1 Egyetem Square, H-4032 Debrecen, Hungary; (D.B.); (T.F.)
- Doctoral School of Molecular Cell and Immune Biology, University of Debrecen, 1 Egyetem Square, H-4032 Debrecen, Hungary
| | - Tünde Fekete
- Department of Immunology, Faculty of Medicine, University of Debrecen, 1 Egyetem Square, H-4032 Debrecen, Hungary; (D.B.); (T.F.)
| | - Kitti Pázmándi
- Department of Immunology, Faculty of Medicine, University of Debrecen, 1 Egyetem Square, H-4032 Debrecen, Hungary; (D.B.); (T.F.)
- Correspondence: ; Tel./Fax: +36-52-417-159
| |
Collapse
|
11
|
Saraiva M, Vieira P, O'Garra A. Biology and therapeutic potential of interleukin-10. J Exp Med 2020; 217:jem.20190418. [PMID: 31611251 PMCID: PMC7037253 DOI: 10.1084/jem.20190418] [Citation(s) in RCA: 441] [Impact Index Per Article: 110.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/05/2019] [Accepted: 09/11/2019] [Indexed: 12/13/2022] Open
Abstract
The authors review the molecular mechanisms regulating IL-10 production and response and describe classic and novel functions of IL-10 in immune and non-immune cells. They further discuss the therapeutic potential of IL-10 in different diseases and the outstanding questions underlying an effective application of IL-10 in clinical settings. The cytokine IL-10 is a key anti-inflammatory mediator ensuring protection of a host from over-exuberant responses to pathogens and microbiota, while playing important roles in other settings as sterile wound healing, autoimmunity, cancer, and homeostasis. Here we discuss our current understanding of the regulation of IL-10 production and of the molecular pathways associated with IL-10 responses. In addition to IL-10’s classic inhibitory effects on myeloid cells, we also describe the nonclassic roles attributed to this pleiotropic cytokine, including how IL-10 regulates basic processes of neural and adipose cells and how it promotes CD8 T cell activation, as well as epithelial repair. We further discuss its therapeutic potential in the context of different diseases and the outstanding questions that may help develop an effective application of IL-10 in diverse clinical settings.
Collapse
Affiliation(s)
- Margarida Saraiva
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Paulo Vieira
- Department of Immunology, Unité Lymphopoièse, Institut Pasteur, Paris, France.,University Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France.,Institut National de la Santé et de la Recherche Médicale U1223, Paris, France
| | - Anne O'Garra
- Laboratory of Immunoregulation and Infection, The Francis Crick Institute, London, UK.,National Heart and Lung Institute, Imperial College London, UK
| |
Collapse
|
12
|
Wculek SK, Khouili SC, Priego E, Heras-Murillo I, Sancho D. Metabolic Control of Dendritic Cell Functions: Digesting Information. Front Immunol 2019; 10:775. [PMID: 31073300 PMCID: PMC6496459 DOI: 10.3389/fimmu.2019.00775] [Citation(s) in RCA: 126] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 03/25/2019] [Indexed: 12/14/2022] Open
Abstract
Dendritic cells (DCs) control innate and adaptive immunity by patrolling tissues to gather antigens and danger signals derived from microbes and tissue. Subsequently, DCs integrate those environmental cues, orchestrate immunity or tolerance, and regulate tissue homeostasis. Recent advances in the field of immunometabolism highlight the notion that immune cells markedly alter cellular metabolic pathways during differentiation or upon activation, which has important implications on their functionality. Previous studies showed that active oxidative phosphorylation in mitochondria is associated with immature or tolerogenic DCs, while increased glycolysis upon pathogen sensing can promote immunogenic DC functions. However, new results in the last years suggest that regulation of DC metabolism in steady state, after immunogenic activation and during tolerance in different pathophysiological settings, may be more complex. Moreover, ontogenically distinct DC subsets show different functional specializations to control T cell responses. It is, thus, relevant how metabolism influences DC differentiation and plasticity, and what potential metabolic differences exist among DC subsets. Better understanding of the emerging connection between metabolic adaptions and functional DC specification will likely allow the development of therapeutic strategies to manipulate immune responses.
Collapse
Affiliation(s)
- Stefanie K Wculek
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Sofía C Khouili
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Elena Priego
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Ignacio Heras-Murillo
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - David Sancho
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| |
Collapse
|
13
|
Chapman NM, Shrestha S, Chi H. Metabolism in Immune Cell Differentiation and Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1011:1-85. [PMID: 28875486 DOI: 10.1007/978-94-024-1170-6_1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The immune system is a central determinant of organismal health. Functional immune responses require quiescent immune cells to rapidly grow, proliferate, and acquire effector functions when they sense infectious agents or other insults. Specialized metabolic programs are critical regulators of immune responses, and alterations in immune metabolism can cause immunological disorders. There has thus been growing interest in understanding how metabolic processes control immune cell functions under normal and pathophysiological conditions. In this chapter, we summarize how metabolic programs are tuned and what the physiological consequences of metabolic reprogramming are as they relate to immune cell homeostasis, differentiation, and function.
Collapse
Affiliation(s)
- Nicole M Chapman
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Sharad Shrestha
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Hongbo Chi
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA.
| |
Collapse
|
14
|
Cangemi M, Montico B, Faè DA, Steffan A, Dolcetti R. Dissecting the Multiplicity of Immune Effects of Immunosuppressive Drugs to Better Predict the Risk of de novo Malignancies in Solid Organ Transplant Patients. Front Oncol 2019; 9:160. [PMID: 30972289 PMCID: PMC6445870 DOI: 10.3389/fonc.2019.00160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 02/25/2019] [Indexed: 12/15/2022] Open
Abstract
De novo malignancies constitute an emerging cause of morbidity after solid organ transplant (SOT), significantly affecting the long-term survival of transplant recipients. Pharmacologic immunosuppression may functionally impair the immunosurveillance in these patients, thereby increasing the risk of cancer development. Nevertheless, the multiplicity and heterogeneity of the immune effects induced by immunosuppressive drugs limit the current possibilities to reliably predict the risk of de novo malignancy in SOT patients. Therefore, there is the pressing need to better characterize the immune dysfunctions induced by the different immunosuppressive regimens administered to prevent allograft rejection to tailor more precisely the therapeutic schedule and decrease the risk of de novo malignancies. We herein highlight the impact exerted by different classes of immunosuppressants on the most relevant immune cells, with a particular focus on the effects on dendritic cells (DCs), the main regulators of the balance between immunosurveillance and tolerance.
Collapse
Affiliation(s)
- Michela Cangemi
- Immunopathology and Cancer Biomarkers, Translational Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Barbara Montico
- Immunopathology and Cancer Biomarkers, Translational Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Damiana A Faè
- Immunopathology and Cancer Biomarkers, Translational Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Agostino Steffan
- Immunopathology and Cancer Biomarkers, Translational Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Riccardo Dolcetti
- Translational Research Institute, University of Queensland Diamantina Institute, Brisbane, QLD, Australia
| |
Collapse
|
15
|
Snyder JP, Amiel E. Regulation of Dendritic Cell Immune Function and Metabolism by Cellular Nutrient Sensor Mammalian Target of Rapamycin (mTOR). Front Immunol 2019; 9:3145. [PMID: 30692999 PMCID: PMC6339945 DOI: 10.3389/fimmu.2018.03145] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 12/19/2018] [Indexed: 12/13/2022] Open
Abstract
Dendritic cell (DC) activation is characterized by an acute increase in glucose metabolic flux that is required to fuel the high anabolic rates associated with DC activation. Inhibition of glycolysis significantly attenuates most aspects of DC immune effector function including antigen presentation, inflammatory cytokine production, and T cell stimulatory capacity. The cellular nutrient sensor mammalian/mechanistic Target of Rapamycin (mTOR) is an important upstream regulator of glycolytic metabolism and plays a central role in coordinating DC metabolic changes and immune responses. Because mTOR signaling can be activated by a variety of immunological stimuli, including signaling through the Toll-like Receptor (TLR) family of receptors, mTOR is involved in orchestrating many aspects of the DC metabolic response to microbial stimuli. It has become increasingly clear that mTOR's role in promoting or attenuating inflammatory processes in DCs is highly context-dependent and varies according to specific cellular subsets and the immunological conditions being studied. This review will address key aspects of the complex role of mTOR in regulating DC metabolism and effector function.
Collapse
Affiliation(s)
- Julia P Snyder
- Predoctoral student of the Cellular, Molecular, and Biomedical (CMB) Sciences Graduate Program at the University of Vermont, Burlington, VT, United States
| | - Eyal Amiel
- Department of Biomedical and Health Sciences, College of Nursing and Health Sciences, University of Vermont, Burlington, VT, United States
| |
Collapse
|
16
|
|
17
|
Bodur C, Kazyken D, Huang K, Ekim Ustunel B, Siroky KA, Tooley AS, Gonzalez IE, Foley DH, Acosta-Jaquez HA, Barnes TM, Steinl GK, Cho KW, Lumeng CN, Riddle SM, Myers MG, Fingar DC. The IKK-related kinase TBK1 activates mTORC1 directly in response to growth factors and innate immune agonists. EMBO J 2018; 37:19-38. [PMID: 29150432 PMCID: PMC5753041 DOI: 10.15252/embj.201696164] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 10/11/2017] [Accepted: 10/12/2017] [Indexed: 01/15/2023] Open
Abstract
The innate immune kinase TBK1 initiates inflammatory responses to combat infectious pathogens by driving production of type I interferons. TBK1 also controls metabolic processes and promotes oncogene-induced cell proliferation and survival. Here, we demonstrate that TBK1 activates mTOR complex 1 (mTORC1) directly. In cultured cells, TBK1 associates with and activates mTORC1 through site-specific mTOR phosphorylation (on S2159) in response to certain growth factor receptors (i.e., EGF-receptor but not insulin receptor) and pathogen recognition receptors (PRRs) (i.e., TLR3; TLR4), revealing a stimulus-selective role for TBK1 in mTORC1 regulation. By studying cultured macrophages and those isolated from genome edited mTOR S2159A knock-in mice, we show that mTOR S2159 phosphorylation promotes mTORC1 signaling, IRF3 nuclear translocation, and IFN-β production. These data demonstrate a direct mechanistic link between TBK1 and mTORC1 function as well as physiologic significance of the TBK1-mTORC1 axis in control of innate immune function. These data unveil TBK1 as a direct mTORC1 activator and suggest unanticipated roles for mTORC1 downstream of TBK1 in control of innate immunity, tumorigenesis, and disorders linked to chronic inflammation.
Collapse
Affiliation(s)
- Cagri Bodur
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Dubek Kazyken
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kezhen Huang
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Bilgen Ekim Ustunel
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kate A Siroky
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Aaron Seth Tooley
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ian E Gonzalez
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Daniel H Foley
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Hugo A Acosta-Jaquez
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Tammy M Barnes
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Gabrielle K Steinl
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kae-Won Cho
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Martin G Myers
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Diane C Fingar
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| |
Collapse
|
18
|
Boor PPC, de Ruiter PE, Asmawidjaja PS, Lubberts E, van der Laan LJW, Kwekkeboom J. JAK-inhibitor tofacitinib suppresses interferon alfa production by plasmacytoid dendritic cells and inhibits arthrogenic and antiviral effects of interferon alfa. Transl Res 2017; 188:67-79. [PMID: 27931982 DOI: 10.1016/j.trsl.2016.11.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 10/14/2016] [Accepted: 11/13/2016] [Indexed: 12/30/2022]
Abstract
Tofacitinib is an oral Janus kinase inhibitor that is effective for the treatment of rheumatoid arthritis and shows encouraging therapeutic effects in several other autoimmune diseases. A prominent adverse effect of tofacitinib therapy is the increased risk of viral infections. Despite its advanced stage of clinical development, the modes of action that mediate the beneficial and adverse effects of tofacitinib in autoimmune diseases remain unclear. Interferon alfa (IFNα) produced by plasmacytoid dendritic cells (PDCs) is critically involved in the pathogenesis of many systemic autoimmune diseases and in immunity to viral infections. Using in vitro culture models with human cells, we studied the effects of tofacitinib on PDC survival and IFNα production, and on arthrogenic and antiviral effects of IFNα. Tofacitinib inhibited the expression of antiapoptotic BCL-A1 and BCL-XL in human PDC and induced PDC apoptosis. TLR7 stimulation upregulated the levels of antiapoptotic Bcl-2 family members and prevented the induction of PDC apoptosis by tofacitinib. However, tofacitinib robustly inhibited the production of IFNα by toll like receptor-stimulated PDC. In addition, tofacitinib profoundly suppressed IFNα-induced upregulation of TLR3 on synovial fibroblasts, thereby inhibiting their cytokine and protease production in response to TLR3 ligation. Finally, tofacitinib counteracted the suppressive effects of IFNα on viral replication. Tofacitinib inhibits PDC survival and IFNα production and suppresses arthrogenic and antiviral effects of IFNα signaling. Inhibition of the IFNα pathway at 2 levels may contribute to the beneficial effects of tofacitinib in autoimmune diseases and explain the increased viral infection rates observed during tofacitinib treatment.
Collapse
Affiliation(s)
- Patrick P C Boor
- Department of Gastroenterology and Hepatology, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands.
| | - Petra E de Ruiter
- Department of Surgery, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands
| | - Patrick S Asmawidjaja
- Department of Rheumatology, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands
| | - Erik Lubberts
- Department of Rheumatology, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands
| | - Luc J W van der Laan
- Department of Surgery, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands
| | - Jaap Kwekkeboom
- Department of Gastroenterology and Hepatology, Erasmus MC - University Medical Centre, Rotterdam, The Netherlands
| |
Collapse
|
19
|
Al-Khami AA, Rodriguez PC, Ochoa AC. Energy metabolic pathways control the fate and function of myeloid immune cells. J Leukoc Biol 2017; 102:369-380. [PMID: 28515225 DOI: 10.1189/jlb.1vmr1216-535r] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 03/27/2017] [Accepted: 04/11/2017] [Indexed: 12/14/2022] Open
Abstract
The past decade has seen a significant interest in investigating the intracellular metabolism of cells of the immune system. This has increased the realization that immune cells endure metabolic reprogramming upon responding to pathogen-derived or inflammatory signals. More importantly, not only does this metabolic switch provide for the bioenergetic and biosynthetic demands but also it, in a highly specific manner, determines the cellular fate and function. In this review, we discuss the metabolic aspects that regulate the differentiation and function of myeloid cells, pivotal for both innate and adaptive immunity. The manipulation of these pathways can alter the function of these cells and therefore, could provide novel therapeutic approaches in cancer and other chronic inflammatory conditions.
Collapse
Affiliation(s)
- Amir A Al-Khami
- Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA; .,Department of Genetics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Paulo C Rodriguez
- Augusta University, Georgia Cancer Center, Augusta, Georgia, USA; and
| | - Augusto C Ochoa
- Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA; .,Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| |
Collapse
|
20
|
TSG-6 Downregulates IFN-Alpha and TNF-Alpha Expression by Suppressing IRF7 Phosphorylation in Human Plasmacytoid Dendritic Cells. Mediators Inflamm 2017; 2017:7462945. [PMID: 28367002 PMCID: PMC5358455 DOI: 10.1155/2017/7462945] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/17/2017] [Accepted: 02/14/2017] [Indexed: 12/13/2022] Open
Abstract
Proinflammatory cytokines such as TNF-α and type I interferons (IFN) are pathogenic signatures of systemic lupus erythematosus, and plasmacytoid dendritic cells (pDCs) play a major role by predominantly producing IFN-α. Given the rise of importance in identifying tumor necrosis stimulated gene 6 (TSG-6) as a key anti-inflammatory regulator, we investigate its function and its ability to counteract proinflammatory cytokine secretion by pDCs in vitro. CpG-A and R837 induced significant endogenous TSG-6 expression in the pDC cell-line GEN2.2. Following recombinant human TSG-6 treatment and CpG-A or R837 stimulation, significant reduction in IFN-α and TNF-α was observed in healthy donors' pDCs, and the same phenomenon was confirmed in GEN2.2. By CD44 blocking assay, we deduced that the suppressive effect of TSG-6 is mediated by CD44, by reducing IRF-7 phosphorylation. Our findings suggest that TSG-6 and its downstream signalling pathway could potentially be targeted to modulate proinflammatory cytokine expression in pDCs.
Collapse
|
21
|
Northrup L, Sullivan BP, Hartwell BL, Garza A, Berkland C. Screening Immunomodulators To Skew the Antigen-Specific Autoimmune Response. Mol Pharm 2016; 14:66-80. [PMID: 28043135 DOI: 10.1021/acs.molpharmaceut.6b00725] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Current therapies to treat autoimmune diseases often result in side effects such as nonspecific immunosuppression. Therapies that can induce antigen-specific immune tolerance provide an opportunity to reverse autoimmunity and mitigate the risks associated with global immunosuppression. In an effort to induce antigen-specific immune tolerance, co-administration of immunomodulators with autoantigens has been investigated in an effort to reprogram autoimmunity. To date, identifying immunomodulators that may skew the antigen-specific immune response has been ad hoc at best. To address this need, we utilized splenocytes obtained from mice with experimental autoimmune encephalomyelitis (EAE) in order to determine if certain immunomodulators may induce markers of immune tolerance following antigen rechallenge. Of the immunomodulatory compounds investigated, only dexamethasone modified the antigen-specific immune response by skewing the cytokine response and decreasing T-cell populations at a concentration corresponding to a relevant in vivo dose. Thus, antigen-educated EAE splenocytes provide an ex vivo screen for investigating compounds capable of skewing the antigen-specific immune response, and this approach could be extrapolated to antigen-educated cells from other diseases or human tissues.
Collapse
Affiliation(s)
- Laura Northrup
- Department of Pharmaceutical Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Bradley P Sullivan
- Department of Pharmaceutical Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Brittany L Hartwell
- Bioengineering Graduate Program, University of Kansas , Lawrence, Kansas 66045, United States
| | - Aaron Garza
- Department of Chemical and Petroleum Engineering, University of Kansas , Lawrence, Kansas 66045, United States
| | - Cory Berkland
- Department of Pharmaceutical Chemistry, University of Kansas , Lawrence, Kansas 66047, United States.,Bioengineering Graduate Program, University of Kansas , Lawrence, Kansas 66045, United States.,Department of Chemical and Petroleum Engineering, University of Kansas , Lawrence, Kansas 66045, United States
| |
Collapse
|
22
|
Choi SC, Titov AA, Sivakumar R, Li W, Morel L. Immune Cell Metabolism in Systemic Lupus Erythematosus. Curr Rheumatol Rep 2016; 18:66. [DOI: 10.1007/s11926-016-0615-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
23
|
Sukhbaatar N, Hengstschläger M, Weichhart T. mTOR-Mediated Regulation of Dendritic Cell Differentiation and Function. Trends Immunol 2016; 37:778-789. [PMID: 27614799 DOI: 10.1016/j.it.2016.08.009] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/10/2016] [Accepted: 08/15/2016] [Indexed: 01/09/2023]
Abstract
Dendritic cells (DCs) are essential antigen-presenting cells that sample the extra- and intracellular milieu to process antigens for the instruction of T cell responses. The mammalian target of rapamycin (mTOR) network senses environmental cues and is important for numerous cellular processes. This review discusses how DCs use mTOR complexes (mTORC1 and 2) to adapt their cellular metabolism, transcriptional responses, and translation machinery to control DC development, antigen processing, cytokine production, and T cell stimulation. We present a spatiotemporal model suggesting that the mTOR network integrates pattern recognition and growth factor receptor activation with nutritional information from the cell and surrounding tissue to support T cell stimulation and tolerance. mTOR develops into a central player that regulates DC differentiation and immune functions.
Collapse
Affiliation(s)
- Nyamdelger Sukhbaatar
- Medical University of Vienna, Institute of Medical Genetics, Währingerstrasse 10, 1090 Vienna, Austria
| | - Markus Hengstschläger
- Medical University of Vienna, Institute of Medical Genetics, Währingerstrasse 10, 1090 Vienna, Austria
| | - Thomas Weichhart
- Medical University of Vienna, Institute of Medical Genetics, Währingerstrasse 10, 1090 Vienna, Austria.
| |
Collapse
|
24
|
Roles of mTOR complexes in the kidney: implications for renal disease and transplantation. Nat Rev Nephrol 2016; 12:587-609. [PMID: 27477490 DOI: 10.1038/nrneph.2016.108] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mTOR pathway has a central role in the regulation of cell metabolism, growth and proliferation. Studies involving selective gene targeting of mTOR complexes (mTORC1 and mTORC2) in renal cell populations and/or pharmacologic mTOR inhibition have revealed important roles of mTOR in podocyte homeostasis and tubular transport. Important advances have also been made in understanding the role of mTOR in renal injury, polycystic kidney disease and glomerular diseases, including diabetic nephropathy. Novel insights into the roles of mTORC1 and mTORC2 in the regulation of immune cell homeostasis and function are helping to improve understanding of the complex effects of mTOR targeting on immune responses, including those that impact both de novo renal disease and renal allograft outcomes. Extensive experience in clinical renal transplantation has resulted in successful conversion of patients from calcineurin inhibitors to mTOR inhibitors at various times post-transplantation, with excellent long-term graft function. Widespread use of this practice has, however, been limited owing to mTOR-inhibitor- related toxicities. Unique attributes of mTOR inhibitors include reduced rates of squamous cell carcinoma and cytomegalovirus infection compared to other regimens. As understanding of the mechanisms by which mTORC1 and mTORC2 drive the pathogenesis of renal disease progresses, clinical studies of mTOR pathway targeting will enable testing of evolving hypotheses.
Collapse
|
25
|
Waldner M, Fantus D, Solari M, Thomson AW. New perspectives on mTOR inhibitors (rapamycin, rapalogs and TORKinibs) in transplantation. Br J Clin Pharmacol 2016; 82:1158-1170. [PMID: 26810941 DOI: 10.1111/bcp.12893] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/22/2016] [Accepted: 01/25/2016] [Indexed: 02/06/2023] Open
Abstract
The macrolide rapamycin and its analogues (rapalogs) constitute the first generation of mammalian target of rapamycin (mTOR) inhibitors. Since the introduction of rapamycin as an immunosuppressant, there has been extensive progress in understanding its complex mechanisms of action. New insights into the function of mTOR in different immune cell types, vascular endothelial cells and neoplastic cells have opened new opportunities and challenges regarding mTOR as a pharmacological target. Currently, the two known mTOR complexes, mTOR complex (mTORC) 1 and mTORC2, are the subject of intense investigation, and the introduction of second-generation dual mTORC kinase inhibitors (TORKinibs) and gene knockout mice is helping to uncover the distinct roles of these complexes in different cell types. While the pharmacological profiling of rapalogs is advanced, much less is known about the properties of TORKinibs. A potential benefit of mTOR inhibition in transplantation is improved protection against transplant-associated viral infections compared with standard calcineurin inhibitor-based immunosuppression. Preclinical and clinical data also underscore the potentially favourable antitumour effects of mTOR inhibitors in regard to transplant-associated malignancies and as a novel treatment option for various other cancers. Many aspects of the mechanisms of action of mTOR inhibitors and their clinical implications remain unknown. In this brief review we discuss new findings and perspectives of mTOR inhibitors in transplantation.
Collapse
Affiliation(s)
- Matthias Waldner
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Plastic Surgery, University of Zurich, Zurich, Switzerland
| | - Daniel Fantus
- Starzl Transplantation Institute and Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mario Solari
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Angus W Thomson
- Starzl Transplantation Institute and Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA. .,Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
26
|
O'Neill LAJ, Pearce EJ. Immunometabolism governs dendritic cell and macrophage function. J Exp Med 2016; 213:15-23. [PMID: 26694970 PMCID: PMC4710204 DOI: 10.1084/jem.20151570] [Citation(s) in RCA: 1078] [Impact Index Per Article: 134.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/16/2015] [Indexed: 12/12/2022] Open
Abstract
Recent studies on intracellular metabolism in dendritic cells (DCs) and macrophages provide new insights on the functioning of these critical controllers of innate and adaptive immunity. Both cell types undergo profound metabolic reprogramming in response to environmental cues, such as hypoxia or nutrient alterations, but importantly also in response to danger signals and cytokines. Metabolites such as succinate and citrate have a direct impact on the functioning of macrophages. Immunogenicity and tolerogenicity of DCs is also determined by anabolic and catabolic processes, respectively. These findings provide new prospects for therapeutic manipulation in inflammatory diseases and cancer.
Collapse
Affiliation(s)
- Luke A J O'Neill
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College, Dublin 2, Ireland
| | - Edward J Pearce
- Department of Immunometabolism, Max Planck Institute of Immunobiology and Epigenetics, D-79108 Freiburg, Germany
| |
Collapse
|
27
|
Fantus D, Thomson AW. Evolving perspectives of mTOR complexes in immunity and transplantation. Am J Transplant 2015; 15:891-902. [PMID: 25737114 DOI: 10.1111/ajt.13151] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 11/17/2014] [Accepted: 12/06/2014] [Indexed: 01/25/2023]
Abstract
Since the discovery of Rapamycin (RAPA) and its immunosuppressive properties, enormous progress has been made in characterizing the mechanistic target of rapamycin (mTOR). Use of RAPA and its analogues (rapalogs) as anti-rejection agents has been accompanied by extensive investigation of how targeting of mTOR complex 1 (mTORC1), the principal target of RAPA, and more recently mTORC2, affects the function of immune cells, as well as vascular endothelial cells, that play crucial roles in regulation of allograft rejection. While considerable knowledge has accumulated on the function of mTORC1 and 2 in T cells, understanding of the differential roles of these complexes in antigen-presenting cells, NK cells and B cells/plasma cells is only beginning to emerge. Immune cell-specific targeting of mTORC1 or mTORC2, together with use of novel, second generation, dual mTORC kinase inhibitors (TORKinibs) have started to play an important role in elucidating the roles of these complexes and their potential for targeting in transplantation. Much remains unknown about the role of mTOR complexes and the consequences of mTOR targeting on immune reactivity in clinical transplantation. Here we address recent advances in understanding and evolving perspectives of the role of mTOR complexes and mTOR targeting in immunity, with extrapolation to transplantation.
Collapse
Affiliation(s)
- D Fantus
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | | |
Collapse
|
28
|
Synergy between rapamycin and FLT3 ligand enhances plasmacytoid dendritic cell-dependent induction of CD4+CD25+FoxP3+ Treg. Blood 2015; 125:2937-47. [PMID: 25833958 DOI: 10.1182/blood-2014-09-599266] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 03/22/2015] [Indexed: 01/09/2023] Open
Abstract
CD4(+)CD25(+)FoxP3(+) regulatory T cells (Treg) are critical elements for maintaining immune tolerance, for instance to exogenous antigens that are introduced during therapeutic interventions such as cell/organ transplant or gene/protein replacement therapy. Coadministration of antigen with rapamycin simultaneously promotes deletion of conventional CD4(+) T cells and induction of Treg. Here, we report that the cytokine FMS-like receptor tyrosine kinase ligand (Flt3L) enhances the in vivo effect of rapamycin. This occurs via selective expansion of plasmacytoid dendritic cells (pDCs), which further augments the number of Treg. Whereas in conventional DCs, rapamycin effectively blocks mammalian target of rapamycin (mTOR) 1 signaling induced by Flt3L, increased mTOR1 activity renders pDCs more resistant to inhibition by rapamycin. Consequently, Flt3L and rapamycin synergistically promote induction of antigen-specific Treg via selective expansion of pDCs. This concept is supported by the finding that Treg induction is abrogated upon pDC depletion. The combination with pDCs and rapamycin is requisite for Flt3L/antigen-induced Treg induction because Flt3L/antigen by itself fails to induce Treg. As co-administering Flt3L, rapamycin, and antigen blocked CD8(+) T-cell and antibody responses in models of gene and protein therapy, we conclude that the differential effect of rapamycin on DC subsets can be exploited for improved tolerance induction.
Collapse
|
29
|
Abstract
The past 15 years have seen enormous advances in our understanding of the receptor and signalling systems that allow dendritic cells (DCs) to respond to pathogens or other danger signals and initiate innate and adaptive immune responses. We are now beginning to appreciate that many of these pathways not only stimulate changes in the expression of genes that control DC immune functions, but also affect metabolic pathways, thereby integrating the cellular requirements of the activation process. In this Review, we focus on this relatively new area of research and attempt to describe an integrated view of DC immunometabolism.
Collapse
Affiliation(s)
- Edward J Pearce
- Department of Pathology and Immunology, Division of Immunobiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Bart Everts
- Department of Parasitology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| |
Collapse
|
30
|
Argüello RJ, Rodriguez Rodrigues C, Gatti E, Pierre P. Protein synthesis regulation, a pillar of strength for innate immunity? Curr Opin Immunol 2014; 32:28-35. [PMID: 25553394 DOI: 10.1016/j.coi.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
Recognition of pathogen derived molecules by Pattern Recognition Receptors (PRR) induces the production of cytokines (i.e. type I interferons) that stimulate the surrounding cells to transcribe and translate hundreds of genes, in order to prevent further infection and organize the immune response. Here, we report on the rising matter that metabolism sensing and gene expression control at the level of mRNA translation, allow swift responses that mobilize host defenses and coordinate innate responses to infection.
Collapse
Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Christian Rodriguez Rodrigues
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| |
Collapse
|
31
|
The emerging role of mTOR signalling in antibacterial immunity. Immunol Cell Biol 2014; 92:346-53. [PMID: 24518980 DOI: 10.1038/icb.2014.3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 12/17/2013] [Accepted: 12/18/2013] [Indexed: 12/14/2022]
Abstract
Mammalian target of rapamycin (mTOR) is a central regulator of cellular metabolic homeostasis that is highly conserved in evolution. Recent evidence has revealed the existence of a complex interplay between mTOR signalling and immunity. We review here the emerging role of mTOR signalling in the regulation of Toll-like receptor-dependent innate responses and in the activation of T cells and antigen-presenting cells. We also highlight the importance of amino-acid starvation-driven mTOR inhibition in the control of autophagy and intracellular bacterial clearance.
Collapse
|