TY - JOUR
T1 - An NK cell population lacking FcRγ is expanded in chronically infected HIV patient
AU - Zhou, J.
AU - Amran, Fathiah
AU - Kramski, M.
AU - Angelovich, T.A.
AU - Elliott, J.
AU - Hearps, A.C.
AU - Price, Patricia
AU - Jaworowski, A.
PY - 2015
Y1 - 2015
N2 - Copyright © 2015 by The American Association of Immunologists, Inc. We previously demonstrated that NK cells from HIV-infected individuals have elevated expression of activation markers, spontaneously degranulate ex vivo, and decrease expression of a signal-transducing protein for NK-activating receptors, FcRγ. Importantly, these changes were maintained in virologically suppressed (VS) individuals receiving combination antiretroviral therapy (cART). In this study, we show that loss of FcRγ is caused by the expansion of a novel subset of FcRγ- CD56dim NK cells with an altered activation receptor repertoire and biological properties. In a cross-sectional study, FcRγ- NK cells as a proportion of total CD56dim NK cells increased in cART-naive viremic HIV-infected individuals (median [interquartile range] = 25.9 [12.6- 56.1] compared with 3.80 [1.15-11.5] for HIV- controls, p <0.0001) and in VS HIV-infected individuals (22.7 [13.1-56.2] compared with 3.80 [1.15-11.5], p = 0.0004), with no difference between cART-naive and VS patients (p = 0.93). FcRγ-NK cells expressed no NKp30 or NKp46. They showed greater Ab-dependent cellular cytotoxicity activity against rituximab-opsonized Raji cells and in a whole-blood assay measuring NK responses to overlapping HIV peptides, despite having reduced CD16 expression compared with conventional NK cells. Their prevalence correlated with CMV Ab titers in HIV- subjects but not in HIV,+ individuals, and with the inflammatory marker CXCL10 in both groups. The expansion of a subset of NK cells that lacks NKp30 and NKp46 to ∼90% of CD56dim NK cells in some VS HIV+ individuals may influence NK-mediated immunosurveillance in patients receiving cART.
AB - Copyright © 2015 by The American Association of Immunologists, Inc. We previously demonstrated that NK cells from HIV-infected individuals have elevated expression of activation markers, spontaneously degranulate ex vivo, and decrease expression of a signal-transducing protein for NK-activating receptors, FcRγ. Importantly, these changes were maintained in virologically suppressed (VS) individuals receiving combination antiretroviral therapy (cART). In this study, we show that loss of FcRγ is caused by the expansion of a novel subset of FcRγ- CD56dim NK cells with an altered activation receptor repertoire and biological properties. In a cross-sectional study, FcRγ- NK cells as a proportion of total CD56dim NK cells increased in cART-naive viremic HIV-infected individuals (median [interquartile range] = 25.9 [12.6- 56.1] compared with 3.80 [1.15-11.5] for HIV- controls, p <0.0001) and in VS HIV-infected individuals (22.7 [13.1-56.2] compared with 3.80 [1.15-11.5], p = 0.0004), with no difference between cART-naive and VS patients (p = 0.93). FcRγ-NK cells expressed no NKp30 or NKp46. They showed greater Ab-dependent cellular cytotoxicity activity against rituximab-opsonized Raji cells and in a whole-blood assay measuring NK responses to overlapping HIV peptides, despite having reduced CD16 expression compared with conventional NK cells. Their prevalence correlated with CMV Ab titers in HIV- subjects but not in HIV,+ individuals, and with the inflammatory marker CXCL10 in both groups. The expansion of a subset of NK cells that lacks NKp30 and NKp46 to ∼90% of CD56dim NK cells in some VS HIV+ individuals may influence NK-mediated immunosurveillance in patients receiving cART.
U2 - 10.4049/jimmunol.1402448
DO - 10.4049/jimmunol.1402448
M3 - Article
SN - 0022-1767
VL - 194
SP - 4688
EP - 4697
JO - Journal of Immunology
JF - Journal of Immunology
IS - 10
ER -