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Ivanova M, Al Hadra B, Yordanov S, Lesichkova S, Stoyanov H, Shivarov V, Deliverska E. Associations of high-resolution-typing-defined MICA and MICB polymorphisms, and the levels of soluble MICA and MICB with Oral Squamous Cell Carcinoma in Bulgarian patients. J Oral Pathol Med 2021; 50:758-765. [PMID: 33835601 DOI: 10.1111/jop.13185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/15/2021] [Accepted: 04/01/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Oral Squamous Cell Carcinoma (OSCC) is a malignancy characterized by an aggressive tumor growth and significant mortality. Clarifying mechanisms responsible for immunomodulation are among the main challenges for the development of personalized approaches for the management of patients with Oral Squamous Cell Carcinoma. The aim of the present study was to analyze the relevance of MICA and MICB to Oral Squamous Cell Carcinoma pathogenesis focusing on allele polymorphisms and the levels of soluble MICA and MICB molecules. MATERIALS AND METHODS 73 patients diagnosed with Oral Squamous Cell Carcinoma and 149 healthy controls from the Bulgarian population were included in the study. MICA and MICB polymorphism was analyzed at high-resolution level using Next-Generation Sequencing. Serum levels of soluble MICA and MICB molecules were measured by ELISA. RESULTS Our results show significant protective association with MICB*002:01, while relatively rare alleles MICB*018, *019, and *020 were observed with statistically significant increased frequency in Oral Squamous Cell Carcinoma patients compared to controls. Additionally, a predisposing association was observed for MICA*008:01-MICB*019 haplotype. A correlation analysis between functionally relevant MICA polymorphisms and sMICA showed that homozygosity for MICA-A5.1 or 129Val in OSCC patients was associated with significantly higher serum levels of sMICA. CONCLUSION This is the first study showing significant associations between MICB alleles and Oral Squamous Cell Carcinoma and suggesting the possible role of MICB in immunosurveillance in Oral Squamous Cell Carcinoma development. Observed correlations between the levels of soluble MICA molecules and functionally relevant polymorphisms might represent a further step toward a better understanding of molecular mechanisms of Oral Squamous Cell Carcinoma and developing strategies for therapeutic targeting harnessing effective immunosurveillance.
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Affiliation(s)
- Milena Ivanova
- Department of Clinical Immunology, University Hospital Alexandrovska, Medical University - Sofia, Sofia, Bulgaria
| | - Bushra Al Hadra
- Department of Clinical Immunology, University Hospital Alexandrovska, Medical University - Sofia, Sofia, Bulgaria
| | - Stanislav Yordanov
- Clinic of ENT diseases, University Hospital Tzaritsa Yoanna -ISUL, Medical University -Sofia, Sofia, Bulgaria
| | - Spaska Lesichkova
- Department of Clinical Immunology, University Hospital Alexandrovska, Medical University - Sofia, Sofia, Bulgaria
| | - Hristo Stoyanov
- Department of Dental, Oral and Maxillofacial surgery, FDM, Medical University- Sofia, Sofia, Bulgaria
| | - Velizar Shivarov
- Department of Genetics, Faculty of Biology, Sofia University St. Kliment Ohridski, Sofia, Bulgaria
| | - Elitsa Deliverska
- Department of Dental, Oral and Maxillofacial surgery, FDM, Medical University- Sofia, Sofia, Bulgaria
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Shete S, Liu H, Wang J, Yu R, Sturgis EM, Li G, Dahlstrom KR, Liu Z, Amos CI, Wei Q. A Genome-Wide Association Study Identifies Two Novel Susceptible Regions for Squamous Cell Carcinoma of the Head and Neck. Cancer Res 2020; 80:2451-2460. [PMID: 32276964 PMCID: PMC7299763 DOI: 10.1158/0008-5472.can-19-2360] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 02/06/2020] [Accepted: 04/07/2020] [Indexed: 12/13/2022]
Abstract
To identify genetic variants for risk of squamous cell carcinoma of the head and neck (SCCHN), we conducted a two-phase genome-wide association study consisting of 7,858,089 SNPs in 2,171 cases and 4,493 controls of non-Hispanic white, of which, 434,839 typed and 7,423,250 imputed SNPs were used as the discovery. SNPs with P < 1 × 10-3 were further validated in the OncoArray study of oral and pharynx cancer (5,205 cases and 3,232 controls of European ancestry) from databases of Genotypes and Phenotypes. Meta-analysis of the discovery and replication studies identified one novel locus 6p22.1 (P = 2.96 × 10-9 for the leading rs259919) and two cancer susceptibility loci 6p21.32 (rs3135001, HLA-DQB1) and 6p21.33 (rs1265081, CCHCR1) associated with SCCHN risk. Further stratification by tumor site revealed four known cancer loci (5p15.33, 6p21.32, 6p21.33, and 2p23.1) associated with oral cavity cancer risk and oropharyngeal cancer risk, respectively. In addition, one novel locus 18q22.2 (P = 2.54 × 10-9 for the leading SNP rs142021700) was identified for hypopharynx and larynx cancer risk. For SNPs in those reported or novel loci, we also performed functional annotations by bioinformatics prediction and expression quantitative trait loci analysis. Collectively, our identification of four reported loci (2p23.1, 5p15.33, 6p21.32, and 6p21.33) and two novel loci (6p22.1 and 18q22.2) for SCCHN risk highlight the importance of human leukocyte antigen loci for oropharyngeal cancer risk, suggesting that immunologic mechanisms are implicated in the etiology of this subset of SCCHN. SIGNIFICANCE: Two novel risk loci for SCCHN in non-Hispanic white individuals highlight the importance of immunologic mechanism in the disease etiology.
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Affiliation(s)
- Sanjay Shete
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Hongliang Liu
- Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina
| | - Jian Wang
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Robert Yu
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Erich M Sturgis
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Guojun Li
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Kristina R Dahlstrom
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Zhensheng Liu
- Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina
| | - Christopher I Amos
- The Institute for Clinical and Translational Research, Baylor College of Medicine, Houston, Texas
| | - Qingyi Wei
- Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina.
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina
- Department of Population Health Sciences, Duke University Medical School, Durham, North Carolina
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Onyeaghala G, Lane J, Pankratz N, Nelson HH, Thyagarajan B, Walcheck B, Anderson KE, Prizment AE. Association between MICA polymorphisms, s-MICA levels, and pancreatic cancer risk in a population-based case-control study. PLoS One 2019; 14:e0217868. [PMID: 31166958 PMCID: PMC6550421 DOI: 10.1371/journal.pone.0217868] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/20/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Pancreatic tumor cells may avoid immune surveillance by releasing the transmembrane major histocompatibility complex class I chain-related A (MICA) protein in soluble form (s-MICA). We hypothesized that the presence of the A5.1 polymorphism in the MICA gene, which encodes a truncated MICA protein, is associated with higher s-MICA levels and increased pancreatic cancer risk. METHODS MICA alleles and s-MICA levels were measured in 121 pancreatic cancer cases and 419 controls. General linear regression with a log transformation assessed geometric means of s-MICA levels across MICA alleles. Unconditional logistic regression was used to calculate the odds ratio (OR) and 95% confidence intervals (CI) for pancreatic cancer associated with MICA alleles. RESULTS After multivariate adjustment, participants with at least one copy of the A5.1 allele versus no A5.1 allele had 1.35 (95% CI: 1.05-1.74) times greater s-MICA levels (1.65 times higher for cases and 1.28, for controls) and increased risk of pancreatic cancer (OR = 1.91, 95% CI: 1.05-3.48). CONCLUSIONS Our study suggests higher risk of pancreatic cancer among those with the MICA A5.1 polymorphism, which may be explained by an increase in s-MICA secretion and impaired immune response. IMPACT These findings provide further evidence at the genetic and molecular level of the important role of MICA in pancreatic cancer development, and may have important implications with regards to pancreatic cancer screening.
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Affiliation(s)
- Guillaume Onyeaghala
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States of America
| | - John Lane
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States of America
| | - Nathan Pankratz
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States of America
| | - Heather H. Nelson
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States of America
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
| | - Bharat Thyagarajan
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States of America
| | - Bruce Walcheck
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN, United States of America
| | - Kristin E. Anderson
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States of America
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
| | - Anna E. Prizment
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States of America
- University of Minnesota Masonic Cancer Center, Minneapolis, MN, United States of America
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Na SJ, Kang MJ, Yu DS, Han KD, Lee JH, Park YG, Lee YB. Cancer risk in patients with Behçet disease: A nationwide population-based dynamic cohort study from Korea. J Am Acad Dermatol 2018; 78:464-470.e2. [DOI: 10.1016/j.jaad.2017.09.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/05/2017] [Accepted: 09/16/2017] [Indexed: 12/11/2022]
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Abstract
The major histocompatibility complex class I polypeptide-related sequence A gene (MICA) encodes a membrane-bound protein acting as a ligand to stimulate an activating receptor, NKG2D, expressed on the surface of essentially all human natural killer (NK), γδ T and CD8(+) αβ T cells. MICA protein is absent from most cells but can be induced by infections and oncogenic transformation and is frequently expressed in epithelial tumors. Upon binding to MICA, NKG2D activates cytolytic responses of NK and γδ T cells against infected and tumor cells expressing MICA. Therefore, membrane-bound MICA acts as a signal during the early immune response against infection or spontaneously arising tumors. On the other hand, human tumor cells spontaneously release a soluble form of MICA, causing the downregulation of NKG2D and in turn severe impairment of the antitumor immune response of NK and CD8(+) T cells. This is considered to promote tumor immune evasion and also to compromise host resistance to infections. MICA is the most polymorphic non-classical class I gene. A possible association of MICA polymorphism with genetic predisposition to different cancer types has been investigated in candidate gene-based studies. Two genome-wide association studies have identified loci in MICA that influence susceptibility to cervical neoplasia and hepatitis C virus-induced hepatocellular carcinoma, respectively. Given the current level of interest in the field of MICA gene, we discuss the genetics and biology of the MICA gene and the role of its polymorphism in cancer. Gaps in our understanding and future research needs are also discussed.
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Affiliation(s)
- Dan Chen
- Ministry of Education and Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China; Department of Immunology, Genetics and Pathology, Science for Life Laboratory Uppsala, Uppsala University, Biomedical Center, Box 815, 75108 Uppsala, Sweden
| | - Ulf Gyllensten
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory Uppsala, Uppsala University, Biomedical Center, Box 815, 75108 Uppsala, Sweden
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Gong Z, Luo QZ, Lin L, Su YP, Peng HB, Du K, Yu P, Wang SP. Association of MICA gene polymorphisms with liver fibrosis in schistosomiasis patients in the Dongting Lake region. Braz J Med Biol Res 2012; 45:222-9. [PMID: 22370708 PMCID: PMC3854198 DOI: 10.1590/s0100-879x2012007500024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2011] [Accepted: 02/13/2012] [Indexed: 11/22/2022] Open
Abstract
Major histocompatibility complex class I chain-related A (MICA) is a highly polymorphic gene located within the MHC class I region of the human genome. Expressed as a cell surface glycoprotein, MICA modulates immune surveillance by binding to its cognate receptor on natural killer cells, NKG2D, and its genetic polymorphisms have been recently associated with susceptibility to some infectious diseases. We determined whether MICA polymorphisms were associated with the high rate of Schistosoma parasitic worm infection or severity of disease outcome in the Dongting Lake region of Hunan Province, China. Polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (SBT) were applied for high-resolution allele typing of schistosomiasis cases (N = 103, age range = 36.2-80.5 years, 64 males and 39 females) and healthy controls (N = 141, age range = 28.6-73.3 years, 73 males and 68 females). Fourteen MICA alleles and five short-tandem repeat (STR) alleles were identified among the two populations. Three (MICA*012:01/02, MICA*017 and MICA*027) showed a higher frequency in healthy controls than in schistosomiasis patients, but the difference was not significantly correlated with susceptibility to S. japonicum infection (Pc > 0.05). In contrast, higher MICA*A5 allele frequency was significantly correlated with advanced liver fibrosis (Pc < 0.05). Furthermore, the distribution profile of MICA alleles in this Hunan Han population was significantly different from those published for Korean, Thai, American-Caucasian, and Afro-American populations (P < 0.01), but similar to other Han populations within China (P > 0.05). This study provides the initial evidence that MICA genetic polymorphisms may underlie the severity of liver fibrosis occurring in schistosomiasis patients from the Dongting Lake region.
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Affiliation(s)
- Zheng Gong
- Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
| | - Qi-Zhi Luo
- Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
| | - Lin Lin
- Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
| | - Yu-Ping Su
- Central Blood Bank in Yueyang, Yueyang, Hunan Province China
| | - Hai-Bo Peng
- Central Blood Bank in Yueyang, Yueyang, Hunan Province China
| | - Kun Du
- Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
| | - Ping Yu
- Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
| | - Shi-Ping Wang
- Key Laboratory of Schistosomiasis in Hunan, Department of Parasitology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province China
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Liu CJ, Lui MT, Chen HL, Lin SC, Chang KW. MICA and MICB overexpression in oral squamous cell carcinoma. J Oral Pathol Med 2006; 36:43-7. [PMID: 17181741 DOI: 10.1111/j.1600-0714.2006.00471.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND The concentration of MICA in serum seems be a good candidate marker in cancer. Previous studies from our laboratory have shown that the polymorphic MIC gene may confer a risk for oral squamous cell carcinoma (OSCC). The study investigated the expression levels of MICA and MICB of OSCC patients and cancer cell lines. MATERIAL AND METHODS We used RT-PCR to analyze the mRNA expression of MICA and MICB in four oral cancer cell lines compared with three normal human oral keratinocyte (NHOK) cell lines and in tissues from 36 patients with OSCC comparing tumor tissue with non-cancerous matched tissue (NCMT). RESULTS Endogenous MICB mRNA expression in OSCC cell lines was significantly higher than that in NHOK (1.40 +/- 0.27 vs. 0.40 +/- 0.16; P = 0.04). In 20 of 36 sets of tissue from patients with OSCC, MICB mRNA expression was higher in the cancerous tissue than in the NCMT. The mean MICB mRNA expression in OSCC tissues was significantly higher than in NCMT (0.39 +/- 0.08 vs. 0.14 +/- 0.03, P = 0.009, paired t-test). A significantly lower MICA mRNA was found in patients who chewed areca nut compared with those who did not use areca (P = 0.001) and in patients with well-differentiated tumors compared with those with less well-differentiated tumors (P = 0.02). CONCLUSION MICA and MICB mRNA expression may be increased in OSCC but there appears to be individual variation.
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Affiliation(s)
- Chung-Ji Liu
- School of Dentistry, National Yang-Ming University, Peitou, Taipei 112, Taiwan
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Reinders J, Rozemuller EH, van der Ven KJW, Caillat-Zucman S, Slootweg PJ, de Weger RA, Tilanus MGJ. MHC Class I Chain-Related Gene A Diversity in Head and Neck Squamous Cell Carcinoma. Hum Immunol 2006; 67:196-203. [PMID: 16698442 DOI: 10.1016/j.humimm.2006.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Indexed: 11/23/2022]
Abstract
Many immune-related genes are located within the human leukocyte antigen (HLA) region on chromosome 6. The MHC class I chain-related gene A (MICA), located centromeric of HLA-B, is involved in the innate and adaptive immune response through activation of NK and T cells. Differences of MICA transmembrane repeat lengths have been associated with diseases and expression is observed on epithelial tumors. Head and neck squamous cell carcinoma (HNSCC) is an epithelial tumor. In the present study we evaluated the MICA repeat length diversity in relation to MICA expression in Dutch HNSCC patients. MICA short tandem repeat analysis indicated a significant decrease in the frequency for the MICA-A9 repeat in patients diagnosed with oral cavity squamous cell carcinoma (SCC) but not in patients with SCC in the hypoharynx, larynx, or oropharynx. Interestingly, the majority of patients expressed MICA as observed with immunohistochemical staining whereas no soluble MICA was detected in patients' sera by enzyme-linked immunosorbent assay. In conclusion, the length of the MICA transmembrane repeats in Dutch HNSCC patients does not influence the MICA expression on tumor cells.
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Affiliation(s)
- Judith Reinders
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
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Lo SS, Lee YJ, Wu CW, Liu CJ, Huang JW, Lui WY. The increase of MICA gene A9 allele associated with gastric cancer and less schirrous change. Br J Cancer 2004; 90:1809-13. [PMID: 15150599 PMCID: PMC2409751 DOI: 10.1038/sj.bjc.6601750] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Since surgical resection is the principal treatment of gastric cancer, early detection is the only effective strategy against this disease at present. Recently, a new polymorphic gene family, the major histocompatibility complex class I chain-related (MIC) genes located about 40 kb centromeric to HLA-B gene has been proposed. This family consists of five genes (A, B, C, D and E). Among them, MICA has five various alleles (A4, A5, A5.1, A6 and A9), which can be used as a polymorphic marker for genetic mapping and for disease susceptibility. The MICA polymorphism was studied in our gastric cancer patients to see if there is any possible correlation with genetic predisposition and clinicopathological factors. Genomic DNA was extracted from fresh or frozen peripheral blood leukocytes in 107 patients with gastric adenocarcinoma who underwent gastrectomy in our hospital and 351 noncancer controls. MICA polymorphism was analysed by using PCR-based technique. The results showed both phenotypic and allele frequencies of allele A9 in patients with gastric cancer were significantly higher than controls (33 vs 17.6%, P=0.005; 17 vs 9.9%, P=0.02). Gastric adenocarcinoma with allele A9 was associated with less schirrous change than those without (P=0.014). MICA gene A9 allele might confer the risk of gastric cancer and associate with less schirrous change. The mechanisms among them deserve further investigation.
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Affiliation(s)
- S-S Lo
- I-Lan Hospital, DOH, Taipei, Taiwan.
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Collins RWM. Human MHC class I chain related (MIC) genes: their biological function and relevance to disease and transplantation. ACTA ACUST UNITED AC 2004; 31:105-14. [PMID: 15182323 DOI: 10.1111/j.1365-2370.2004.00457.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Major histocompatibility complex (MHC) class I chain related (MIC) molecules show homology with classical human leukocyte antigen (HLA) molecules, but they do not combine with beta2 microglobulin, do not bind peptide and are not expressed on normal circulating lymphocytes. In response to stress, MIC proteins are expressed on the cell surface of freshly isolated gastric epithelium, endothelial cells and fibroblasts and engage the activating natural killer cell receptor NKG2D, which is found on many cells within the immune system. Despite the highly polymorphic nature of MIC genes, only one polymorphic position has been identified that appears to affect the binding of NKG2D. Alleles with a methionine at codon 129 have a 10-50-fold greater capacity to complex NKG2D than alleles with a valine at this position. Renal and pancreatic grafts with evidence of both acute and chronic rejection have been shown to express MIC proteins, and anti-MIC antibodies have been identified in the serum of these patients. Some MIC molecules which are expressed by tumours appear to shed and solubilize in plasma. This soluble form of MIC engages cells expressing NKG2D, rendering them inactive, and impairs tumour cytolysis. Similarly, a protein encoded by human cytomegalovirus (CMV) prevents MICB surface expression and subsequent NKG2D interaction. Whereas the benefit of solid organ transplantation may be hindered by the expression of MIC molecules on grafts, tumours and viruses may take advantage of the expression of MIC molecules on transformed and virus-infected cells in order to evade this recognition pathway.
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Affiliation(s)
- R W M Collins
- Division of Immunology, Infection and Inflammatory Disease, King's College London, UK.
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Radosavljevic M, Bahram S. In vivo immunogenetics: from MIC to RAET1 loci. Immunogenetics 2003; 55:1-9. [PMID: 12715243 DOI: 10.1007/s00251-003-0546-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2003] [Accepted: 01/28/2003] [Indexed: 10/25/2022]
Abstract
The major histocompatibility complex (MHC) comprises approximately one thousandth of the genome and encompasses its most polymorphic members. This diversity enables the MHC, at the population level, to counteract the extraordinarily diverse microbiological threats. Reviewed here are two separate sets of MHC class I genes: MIC and RAET1. Whilst the former are encoded within the MHC (6p21.3), the latter are located on the opposite arm of the same chromosome (6q24.2-q25.3). Differing from the prototypical class I genes in structure, transcription, diversity and potential function, they both exemplify the versatility of the MHC fold, despite convergence onto a single ligand, the activatory C-type lectin-like receptor, NKG2D. Why the immune system uses two distinct gene families to interact with a unique ligand remains a fascinating question. To answer this question, the reader will be chronologically exposed to the field whilst following a single thread, i.e. genomics and gene diversity.
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Affiliation(s)
- Mirjana Radosavljevic
- INSERM-CReS Human Molecular Immunogenetics, Centre de Recherche d'Immunologie et d'Hématologie, 4 rue Kirschleger, 67085, Strasbourg Cedex, France
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