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Fareez F, Wang BH, Brain I, Lu JQ. Lymphomas in patients with neurofibromatosis type 1 (NF1): another malignancy in the NF1 syndrome? Pathology 2023; 55:302-314. [PMID: 36774237 DOI: 10.1016/j.pathol.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 12/22/2022] [Accepted: 01/06/2023] [Indexed: 01/21/2023]
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant multisystem syndrome caused by mutations in the neurofibromin 1 (NF1) gene that encodes for the protein neurofibromin acting as a tumour suppressor. Neurofibromin functions primarily as a GTPase-activating protein for the Ras family of oncogenes, which activates many signalling pathways for cell proliferation and differentiation; without neurofibromin, Ras is constitutively activated, thereby turning on many downstream signalling pathways related to oncogenesis. Patients with NF1 have a well known predisposition for certain types of malignancies including malignant peripheral nerve sheath tumours, gliomas, and breast cancers, as well as a potential association of NF1 with lymphoproliferative disorders such as lymphomas. In this article, we review the pathophysiology and tumourigenesis of NF1, previously reported cases of cutaneous lymphomas in NF1 patients along with our case demonstration of a NF1-associated scalp B-cell lymphoma, and NF1-associated extra cutaneous lymphomas. The diagnosis of lymphomas particularly cutaneous lymphomas may be difficult in NF1 patients as they often have skin lesions and/or cutaneous/subcutaneous nodules or tumours like neurofibromas, which raises the possibility of underdiagnosed cutaneous lymphomas in NF1 patients. We also comprehensively discuss the association between NF1 and lymphomas. In summary, most studies support a potential association between NF1 and lymphomas. Further investigation is needed to clarify the association between NF1 and lymphomas in order to bring clinical awareness of possibly underdiagnosed NF1-associated lymphomas and individualised management of NF1 patients to practice.
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Affiliation(s)
- Faiha Fareez
- Department of Pathology and Molecular Medicine, Hamilton, Ontario, Canada
| | - Bill H Wang
- Department of Surgery/Neurosurgery, McMaster University, Hamilton, Ontario, Canada
| | - Ian Brain
- Department of Laboratory Medicine and Pathobiology/Hematopathology, University of Toronto, Toronto, Ontario, Canada
| | - Jian-Qiang Lu
- Department of Pathology and Molecular Medicine, Hamilton, Ontario, Canada; Department of Pathology and Molecular Medicine/Neuropathology, Hamilton General Hospital, Hamilton, Ontario, Canada.
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2
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Brutkiewicz RR, Yunes-Medina L, Liu J. Immune evasion of the CD1d/NKT cell axis. Curr Opin Immunol 2018; 52:87-92. [PMID: 29734045 DOI: 10.1016/j.coi.2018.04.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/19/2018] [Indexed: 01/03/2023]
Abstract
Many reviews on the CD1d/NKT cell axis focus on the ability of CD1d-restricted NKT cells to serve as effector cells in a variety of disorders, be they infectious diseases, cancer or autoimmunity. In contrast, here, we discuss the ways that viruses, bacteria and tumor cells can evade the CD1d/NKT cell axis. As a result, these disease states have a better chance to establish a foothold and potentially cause problems for the subsequent adaptive immune response, as the host tries to rid itself of infections or tumors.
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Affiliation(s)
- Randy R Brutkiewicz
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202-5181, United States.
| | - Laura Yunes-Medina
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202-5181, United States
| | - Jianyun Liu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202-5181, United States
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3
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Khan MA, Aljarbou AN, Aldebasi YH, Alorainy MS, Rahmani AH, Younus H, Khan A. Liposomal formulation of glycosphingolipids from Sphingomonas paucimobilis induces antitumour immunity in mice. J Drug Target 2018; 26:709-719. [PMID: 29307241 DOI: 10.1080/1061186x.2018.1424857] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Natural Killer T (NKT) cells play an important role in host's anti-tumour immune response. Glycosphingolipids (GSLs) isolated from Sphingomonas paucimobilis have the ability to stimulate NKT cells. In this study, the activity of free GSLs or GSLs-incorporated liposomes (glycosphingosomes) was investigated against dimethyl-α-benzanthracene (DMBA)-induced tumours in mice. The anti-tumour immunity of GSLs- or glycosphingosomes-loaded bone marrow-derived dendritic cells (BMDCs) was investigated in tumour-bearing mice. The Immunotherapeutic potential of co-administration of liposomal doxorubicin (Lip-Dox) and GSLs or glycosphingosomes was assessed by measuring cytokine levels and VEGF in the tumour tissues. Pretreatment with glycosphingosomes significantly delayed the frequency of tumour formation. Immunotherapy with glycosphingosomes-loaded BMDCs increased serum IFN-γ level and survival rate in mice. The effect of immunotherapy was dependent on effector functions of NK cells because the depletion of NK cells abolished the effects of immunotherapy. There was reduced tumour growth with low expression of VEGF in the group of mice treated with glycosphingosomes and Lip-Dox combination. Moreover, the splenocytes secreted higher levels of IFN-γ, IL-12 and lower TGF-β level. The results of this study indicate that glycosphingosomes can induce better antitumour immunity and may be considered a novel formulation in antitumour therapy.
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Affiliation(s)
- Masood A Khan
- a College of Applied Medical Sciences , Qassim University , Buraydah , Saudi Arabia
| | - Ahmed N Aljarbou
- b College of Pharmacy , Qassim University , Buraydah , Saudi Arabia
| | - Yousef H Aldebasi
- a College of Applied Medical Sciences , Qassim University , Buraydah , Saudi Arabia
| | | | - Arshad H Rahmani
- a College of Applied Medical Sciences , Qassim University , Buraydah , Saudi Arabia
| | - Hina Younus
- d Interdisciplinary Biotechnology Unit , Aligarh Muslim University , Aligarh , India
| | - Arif Khan
- a College of Applied Medical Sciences , Qassim University , Buraydah , Saudi Arabia
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4
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Liu J, Gallo RM, Khan MA, Renukaradhya GJ, Brutkiewicz RR. Neurofibromin 1 Impairs Natural Killer T-Cell-Dependent Antitumor Immunity against a T-Cell Lymphoma. Front Immunol 2018; 8:1901. [PMID: 29354122 PMCID: PMC5760513 DOI: 10.3389/fimmu.2017.01901] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/13/2017] [Indexed: 12/31/2022] Open
Abstract
Neurofibromin 1 (NF1) is a tumor suppressor gene encoding a Ras GTPase that negatively regulates Ras signaling pathways. Mutations in NF1 are linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. In terms of antitumor immunity, CD1d-dependent natural killer T (NKT) cells play an important role in the innate antitumor immune response. Generally, Type-I NKT cells protect (and Type-II NKT cells impair) host antitumor immunity. We have previously shown that CD1d-mediated antigen presentation to NKT cells is regulated by cell signaling pathways. To study whether a haploinsufficiency in NF1 would affect CD1d-dependent activation of NKT cells, we analyzed the NKT-cell population as well as the functional expression of CD1d in Nf1+/− mice. Nf1+/− mice were found to have similar levels of NKT cells as wildtype (WT) littermates. Interestingly, however, reduced CD1d expression was observed in Nf1+/− mice compared with their WT littermates. When inoculated with a T-cell lymphoma in vivo, Nf1+/− mice survived longer than their WT littermates. Furthermore, blocking CD1d in vivo significantly enhanced antitumor activity in WT, but not in Nf1+/− mice. In contrast, a deficiency in Type-I NKT cells increased antitumor activity in Nf1+/− mice, but not in WT littermates. Therefore, these data suggest that normal NF1 expression impairs CD1d-mediated NKT-cell activation and antitumor activity against a T-cell lymphoma.
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Affiliation(s)
- Jianyun Liu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Richard M Gallo
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Masood A Khan
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States.,College of Applied Medical Sciences, Al-Qassim University, Buraidah, Saudi Arabia
| | - Gourapura J Renukaradhya
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States.,Food Animal Health Research Program (FAHRP), Ohio Agricultural Research and Development Center (OARDC), Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH, United States
| | - Randy R Brutkiewicz
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States
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Immune-Stimulatory and Therapeutic Activity of Tinospora cordifolia: Double-Edged Sword against Salmonellosis. J Immunol Res 2017; 2017:1787803. [PMID: 29318160 PMCID: PMC5727750 DOI: 10.1155/2017/1787803] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 10/17/2017] [Indexed: 11/17/2022] Open
Abstract
The present study was aimed at determining the activity of aqueous and methanolic extracts of Tinospora cordifolia (AETC and METC) against Salmonella typhimurium. In vitro anti-Salmonella activity of T. cordifolia was determined through the broth dilution and agar well diffusion assays. The immune-stimulating potential of AETC or METC was determined by measuring the cytokine levels in the culture supernatants of treated murine J774 macrophages. Antibacterial activity of AETC or METC was determined by treating S. typhimurium-infected macrophages and BALB/C mice. The toxicity of AETC or METC was determined by measuring the levels of liver inflammation markers aspartate transaminase (AST) and alanine transaminase (ALT) and antioxidant enzymes. Macrophages treated with AETC or METC secreted greater levels of IFN-γ, TNF-α, and IL-1β. METC showed greater activity against S. typhimurium infection in macrophages and mice as well. Treatment with METC resulted in increased survival and reduced bacterial load in S. typhimurium-infected mice. Moreover, METC or AETC treatment reduced the liver inflammation and rescued the levels of antioxidant enzymes in S. typhimurium-infected mice. The results of the present study suggest that the use of T. cordifolia may act as a double-edged sword in combating salmonellosis.
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Bailey JC, Iyer AK, Renukaradhya GJ, Lin Y, Nguyen H, Brutkiewicz RR. Inhibition of CD1d-mediated antigen presentation by the transforming growth factor-β/Smad signalling pathway. Immunology 2015; 143:679-91. [PMID: 24990409 DOI: 10.1111/imm.12353] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 06/10/2014] [Accepted: 06/30/2014] [Indexed: 12/14/2022] Open
Abstract
CD1d-mediated lipid antigen presentation activates a subset of innate immune lymphocytes called invariant natural killer T (NKT) cells that, by virtue of their potent cytokine production, bridge the innate and adaptive immune systems. Transforming growth factor (TGF-β) is a known immune modulator that can activate the mitogen-activated protein kinase p38; we have previously shown that p38 is a negative regulator of CD1d-mediated antigen presentation. Several studies implicate a role for TGF-β in the activation of p38. Therefore, we hypothesized that TGF-β would impair antigen presentation by CD1d. Indeed, a dose-dependent decrease in CD1d-mediated antigen presentation and impairment of lipid antigen processing was observed in response to TGF-β treatment. However, it was found that this inhibition was not through p38 activation. Instead, Smads 2, 3 and 4, downstream elements of the TGF-β canonical signalling pathway, contributed to the observed effects. In marked contrast to that observed with CD1d, TGF-β was found to enhance MHC class II-mediated antigen presentation. Overall, these results suggest that the canonical TGF-β/Smad pathway negatively regulates an important arm of the host's innate immune responses - CD1d-mediated lipid antigen presentation to NKT cells.
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Affiliation(s)
- Jennifer C Bailey
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
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Ascough S, Ingram RJ, Chu KK, Reynolds CJ, Musson JA, Doganay M, Metan G, Ozkul Y, Baillie L, Sriskandan S, Moore SJ, Gallagher TB, Dyson H, Williamson ED, Robinson JH, Maillere B, Boyton RJ, Altmann DM. Anthrax lethal factor as an immune target in humans and transgenic mice and the impact of HLA polymorphism on CD4+ T cell immunity. PLoS Pathog 2014; 10:e1004085. [PMID: 24788397 PMCID: PMC4006929 DOI: 10.1371/journal.ppat.1004085] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/07/2014] [Indexed: 11/23/2022] Open
Abstract
Bacillus anthracis produces a binary toxin composed of protective antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). Most studies have concentrated on induction of toxin-specific antibodies as the correlate of protective immunity, in contrast to which understanding of cellular immunity to these toxins and its impact on infection is limited. We characterized CD4+ T cell immunity to LF in a panel of humanized HLA-DR and DQ transgenic mice and in naturally exposed patients. As the variation in antigen presentation governed by HLA polymorphism has a major impact on protective immunity to specific epitopes, we examined relative binding affinities of LF peptides to purified HLA class II molecules, identifying those regions likely to be of broad applicability to human immune studies through their ability to bind multiple alleles. Transgenics differing only in their expression of human HLA class II alleles showed a marked hierarchy of immunity to LF. Immunogenicity in HLA transgenics was primarily restricted to epitopes from domains II and IV of LF and promiscuous, dominant epitopes, common to all HLA types, were identified in domain II. The relevance of this model was further demonstrated by the fact that a number of the immunodominant epitopes identified in mice were recognized by T cells from humans previously infected with cutaneous anthrax and from vaccinated individuals. The ability of the identified epitopes to confer protective immunity was demonstrated by lethal anthrax challenge of HLA transgenic mice immunized with a peptide subunit vaccine comprising the immunodominant epitopes that we identified. Anthrax is of concern with respect to human exposure in endemic regions, concerns about bioterrorism and the considerable global burden of livestock infections. The immunology of this disease remains poorly understood. Vaccination has been based on B. anthracis filtrates or attenuated spore-based vaccines, with more recent trials of next-generation recombinant vaccines. Approaches generally require extensive vaccination regimens and there have been concerns about immunogenicity and adverse reactions. An ongoing need remains for rationally designed, effective and safe anthrax vaccines. The importance of T cell stimulating vaccines is inceasingly recognized. An essential step is an understanding of immunodominant epitopes and their relevance across the diverse HLA immune response genes of human populations. We characterized CD4 T cell immunity to anthrax Lethal Factor (LF), using HLA transgenic mice, as well as testing candidate peptide epitopes for binding to a wide range of HLA alleles. We identified anthrax epitopes, noteworthy in that they elicit exceptionally strong immunity with promiscuous binding across multiple HLA alleles and isotypes. T cell responses in humans exposed to LF through either natural anthrax infection or vaccination were also examined. Epitopes identified as candidates were used to protect HLA transgenic mice from anthrax challenge.
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Affiliation(s)
- Stephanie Ascough
- Department of Medicine, Imperial College London, London, United Kingdom
| | - Rebecca J. Ingram
- Centre for Infection and Immunity, Queen's University Belfast, Belfast, United Kingdom
| | - Karen K. Chu
- Department of Medicine, Imperial College London, London, United Kingdom
| | | | - Julie A. Musson
- Institute for Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Mehmet Doganay
- Department of Infectious Disease, Erciyes University Hospital, Kayseri, Turkey
| | - Gökhan Metan
- Department of Infectious Disease, Erciyes University Hospital, Kayseri, Turkey
| | - Yusuf Ozkul
- Department of Medical Genetics, Erciyes University Hospital, Kayseri, Turkey
| | - Les Baillie
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom
| | | | - Stephen J. Moore
- BIOMET, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Theresa B. Gallagher
- BIOMET, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Hugh Dyson
- Defence Science Technology Laboratory, Porton Down, Salisbury, United Kingdom
| | - E. Diane Williamson
- Defence Science Technology Laboratory, Porton Down, Salisbury, United Kingdom
| | - John H. Robinson
- Institute for Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Bernard Maillere
- CEA, iBiTecS, Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), Gif Sur Yvette, France
| | | | - Daniel M. Altmann
- Department of Medicine, Imperial College London, London, United Kingdom
- * E-mail:
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8
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Anthrax lethal toxin and the induction of CD4 T cell immunity. Toxins (Basel) 2012; 4:878-99. [PMID: 23162703 PMCID: PMC3496994 DOI: 10.3390/toxins4100878] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 10/08/2012] [Accepted: 10/10/2012] [Indexed: 12/27/2022] Open
Abstract
Bacillus anthracis secretes exotoxins which act through several mechanisms including those that can subvert adaptive immunity with respect both to antigen presenting cell and T cell function. The combination of Protective Antigen (PA) and Lethal Factor (LF) forming Lethal Toxin (LT), acts within host cells to down-regulate the mitogen activated protein kinase (MAPK) signaling cascade. Until recently the MAPK kinases were the only known substrate for LT; over the past few years it has become evident that LT also cleaves Nlrp1, leading to inflammasome activation and macrophage death. The predicted downstream consequences of subverting these important cellular pathways are impaired antigen presentation and adaptive immunity. In contrast to this, recent work has indicated that robust memory T cell responses to B. anthracis antigens can be identified following natural anthrax infection. We discuss how LT affects the adaptive immune response and specifically the identification of B. anthracis epitopes that are both immunogenic and protective with the potential for inclusion in protein sub-unit based vaccines.
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Gallo RM, Khan MA, Shi J, Kapur R, Wei L, Bailey JC, Liu J, Brutkiewicz RR. Regulation of the actin cytoskeleton by Rho kinase controls antigen presentation by CD1d. THE JOURNAL OF IMMUNOLOGY 2012; 189:1689-98. [PMID: 22798677 DOI: 10.4049/jimmunol.1101484] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
CD1d molecules are MHC class I-like molecules that present lipid Ags to NKT cells. Although we have previously shown that several different cell signaling molecules can play a role in the control of Ag presentation by CD1d, a defined mechanism by which a cell signaling pathway regulates CD1d function has been unclear. In the current study, we have found that the Rho kinases, Rho-associated, coiled-coil containing protein kinase (ROCK)1 and ROCK2, negatively regulate both human and mouse CD1d-mediated Ag presentation. Inhibition of ROCK pharmacologically, through specific ROCK1 and ROCK2 short hairpin RNA, or by using dendritic cells generated from ROCK1-deficient mice all resulted in enhanced CD1d-mediated Ag presentation compared with controls. ROCK regulates the actin cytoskeleton by phosphorylating LIM kinase, which, in turn, phosphorylates cofilin, prohibiting actin fiber depolymerization. Treatment of APCs with the actin filament depolymerizing agent, cytochalasin D, as well as knockdown of LIM kinase by short hairpin RNA, resulted in enhanced Ag presentation to NKT cells by CD1d, consistent with our ROCK inhibition data. Therefore, our overall results reveal a model whereby CD1d-mediated Ag presentation is negatively regulated by ROCK via its effects on the actin cytoskeleton.
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Affiliation(s)
- Richard M Gallo
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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De Libero G, Mori L. Novel insights into lipid antigen presentation. Trends Immunol 2012; 33:103-11. [PMID: 22342205 DOI: 10.1016/j.it.2012.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 12/20/2011] [Accepted: 01/05/2012] [Indexed: 01/21/2023]
Abstract
T cells recognizing lipid antigens are present in large numbers in circulating blood. They exert multiple functions including immunoregulation, tumour surveillance and protection during infection. Here, we review the latest information on the mechanisms of lipid antigen presentation by CD1 molecules. Recent studies have provided insight into CD1 trafficking within the cell, lipid distribution and handling, CD1 maturation, lipid antigen processing and loading. The structural resolution of all human CD1 molecules has revealed unique features that correlate with function. Molecular mechanisms regulating CD1 expression and multiple evasion mechanisms evolved by viral and bacterial pathogens have been disclosed. With rapid progression, these studies have decoded lipid-specific immunity and have revealed the important immunological role of this type of antigen recognition.
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11
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Gyles CL. Relevance in pathogenesis research. Vet Microbiol 2011; 153:2-12. [PMID: 21592684 DOI: 10.1016/j.vetmic.2011.04.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/09/2011] [Accepted: 04/13/2011] [Indexed: 01/28/2023]
Abstract
Research on pathogenesis of bacterial diseases involves exploration of the intricate and complex interactions among pathogen, host, and environment. Host-parasite-environment interactions that were relatively simple were the first to be understood. They include intoxications in which ingestion of a powerful bacterial toxin was sufficient to cause disease. In more complex cases bacteria occupy a variety of niches in the host and attack at an opportune time. Some bacterial pathogens have a brief encounter with the host; others are long-term guests. This variety of relationships involves a wide range of strategies for survival and transmission of bacterial pathogens. Molecular genetics, genomics and proteomics have facilitated understanding of the pathogens and hosts. Massive information often results from such studies and determining the relevance of the data is frequently a challenge. In vitro studies often attempt to simulate one or two critical aspects of the environment, such as temperature, pH, and iron concentration, that may provide clues as to what goes on in the host. These studies sometimes identify critical bacterial virulence factors but regulation of bacterial virulence and host response is complex and often not well understood. Pathogenesis is a process of continuous change in which timing and degree of gene expression are critical and are highly regulated by the environment. It is impossible to get the full picture without the use of natural or experimental infections, although experimental infections involve ethical and economic considerations which may act as a deterrent.
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Affiliation(s)
- Carlton L Gyles
- Department of Pathobiology, University of Guelph, Guelph, Ontario, N1G 2W1 Canada.
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12
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Odumosu O, Nicholas D, Yano H, Langridge W. AB toxins: a paradigm switch from deadly to desirable. Toxins (Basel) 2010; 2:1612-45. [PMID: 22069653 PMCID: PMC3153263 DOI: 10.3390/toxins2071612] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 06/08/2010] [Accepted: 06/23/2010] [Indexed: 11/16/2022] Open
Abstract
To ensure their survival, a number of bacterial and plant species have evolved a common strategy to capture energy from other biological systems. Being imperfect pathogens, organisms synthesizing multi-subunit AB toxins are responsible for the mortality of millions of people and animals annually. Vaccination against these organisms and their toxins has proved rather ineffective in providing long-term protection from disease. In response to the debilitating effects of AB toxins on epithelial cells of the digestive mucosa, mechanisms underlying toxin immunomodulation of immune responses have become the focus of increasing experimentation. The results of these studies reveal that AB toxins may have a beneficial application as adjuvants for the enhancement of immune protection against infection and autoimmunity. Here, we examine similarities and differences in the structure and function of bacterial and plant AB toxins that underlie their toxicity and their exceptional properties as immunomodulators for stimulating immune responses against infectious disease and for immune suppression of organ-specific autoimmunity.
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Affiliation(s)
- Oludare Odumosu
- Center for Health Disparities and Molecular Medicine, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (O.O.)
- Department of Biochemistry, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (D.N.)
| | - Dequina Nicholas
- Center for Health Disparities and Molecular Medicine, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (O.O.)
- Department of Biochemistry, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (D.N.)
| | - Hiroshi Yano
- Department of Biology, University of Redlands, 1200 East Colton Ave, P.O. Box 3080, Redlands, CA 92373, USA; (H.Y.)
| | - William Langridge
- Center for Health Disparities and Molecular Medicine, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (O.O.)
- Department of Biochemistry, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; (D.N.)
- Author to whom correspondence should be addressed; ; Tel.: +1-909-558-1000 (81362); Fax: +1-909-558-0177
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