TY - JOUR
T1 - HLA-E up-regulation induced by HIV infection may directly contribute to CD94-mediated impairment of NK cells
AU - Martini, F.
AU - Agrati, C.
AU - D'Offizi, G.
AU - Poccia, F.
PY - 2005/4
Y1 - 2005/4
N2 - Alterations in NK cell numbers and function have been repeatedly shown during HIV infection. In this study, NK cell number and MHC class I expression on CD4+ T cells were studied in HIV patients at different stages of disease progression. An increased expression of HLA-E was seen on CD4+ T cells. In parallel, a reduced number of CD94+ NK cells was observed in advanced disease stages. Moreover, a decline in CD94 expression on NK cells was observed at the HIV replication peak in patients undergoing antiretroviral treatment interruption, suggesting a role of viral replication on NK cells alterations. In vitro HIV infection induced a rapid down-regulation of HLA-A,B,C expression, paralleled by an increased expression of HLA-E surface molecules, the formal ligands of CD94 NK receptors. HIV-infected HLA-E expressing cells were able to inhibit NK cell cytotoxicity through HLA-E expression, since cytotoxicity was restored by antibody masking experiments. These data indicate that the CD94/HLA-E interaction may contribute to NK cell dysfunction in HIV infection, suggesting a role of HIV replication in this process.
AB - Alterations in NK cell numbers and function have been repeatedly shown during HIV infection. In this study, NK cell number and MHC class I expression on CD4+ T cells were studied in HIV patients at different stages of disease progression. An increased expression of HLA-E was seen on CD4+ T cells. In parallel, a reduced number of CD94+ NK cells was observed in advanced disease stages. Moreover, a decline in CD94 expression on NK cells was observed at the HIV replication peak in patients undergoing antiretroviral treatment interruption, suggesting a role of viral replication on NK cells alterations. In vitro HIV infection induced a rapid down-regulation of HLA-A,B,C expression, paralleled by an increased expression of HLA-E surface molecules, the formal ligands of CD94 NK receptors. HIV-infected HLA-E expressing cells were able to inhibit NK cell cytotoxicity through HLA-E expression, since cytotoxicity was restored by antibody masking experiments. These data indicate that the CD94/HLA-E interaction may contribute to NK cell dysfunction in HIV infection, suggesting a role of HIV replication in this process.
KW - Innate immunity
KW - Natural Killer cells
KW - Viral escape strategies
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M3 - Article
C2 - 15888249
AN - SCOPUS:20444488405
VL - 18
SP - 269
EP - 276
JO - International Journal of Immunopathology and Pharmacology
JF - International Journal of Immunopathology and Pharmacology
SN - 0394-6320
IS - 2
ER -