title: Induction of cell surface human leukocyte antigen-G expression in pandemic H1N1 2009 and seasonal H1N1 influenza virus-infected patients.
abstract: A novel H1N1 virus of swine origin (H1N1v) recently caused a pandemic; however, knowledge of immunologic aspects of the virus infection are limited. Human leukocyte antigen-G (HLA-G) was speculated to play critical roles in viral infection, although its clinical relevance in H1N1 infection remains unknown. In this study, HLA-G expression in peripheral T lymphocytes, monocytes, and CD4(+) CD25(+) FoxP3+ regulatory T (Treg) cells (in 50 H1N1v-infected and 41 seasonal H1N1-infected patients and 27 control subjects) were analyzed by flow cytometry. Plasma-soluble HLA-G (sHLA-G, in 28 H1N1v-infected, 29 seasonal H1N1-infected patients and 85 control subjects) were determined with enzyme-linked immunosorbent assay. The percentage of HLA-G-positive T lymphocytes and monocytes among patients with H1N1v and seasonal H1N1 infections was dramatically increased compared with controls (all p < 0.001). Treg was markedly increased among H1N1v- infected patients compared with normal controls (p = 0.041), but not for the seasonal H1N1-infected patients. Meanwhile, no significant difference was observed for sHLA-G levels between the groups. Together, cell surface HLA-G expression was markedly induced in H1N1v-infected and seasonal H1N1-infected patients, and increased Treg was observed only in H1N1v-infected patients. Given its immune-suppressive property, elevated cell surface HLA-G expression may help to explain the virus escaping from host immune responses.
authors.affiliation: Human Tissue Bank, Taizhou Hospital of Zhejiang Province, Wenzhou Medical College, Linhai, Zhejiang, China.
authors.forename: Hai-Xiao
authors.initials: HX
authors.lastname: Chen
authors.forename: Bao-Guo
authors.initials: BG
authors.lastname: Chen
authors.forename: Wei-Wu
authors.initials: WW
authors.lastname: Shi
authors.forename: Rui
authors.initials: R
authors.lastname: Zhen
authors.forename: Dan-Ping
authors.initials: DP
authors.lastname: Xu
authors.forename: Aifen
authors.initials: A
authors.lastname: Lin
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Yan
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D006680:HLA Antigens / Q000097:blood / Q000235:genetics* / Q000276:immunology*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000097:blood / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D057131:Immune Evasion; D053118:Influenza A Virus, H1N1 Subtype / Q000502:physiology; D007251:Influenza, Human / Q000097:blood* / Q000276:immunology* / Q000821:virology; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D018655:Lymphocyte Count; D008297:Male; D009000:Monocytes / Q000276:immunology* / Q000378:metabolism; D058873:Pandemics; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D014779:Virus Replication; D055815:Young Adult
chemical_list: D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I