HIV-specific IL-21 producing CD4+ T cells are induced in acute and chronic progressive HIV infection and are associated with relative viral control.
We examined the role of CD4(+) T cell IL-21 production in viral control of HIV infection. HIV-infected individuals had greater circulating IL-21-producing CD4(+) T cells in blood compared with uninfected volunteers. HIV-specific IL-21-producing CD4(+) T cells were detected in blood during untreated acute and chronic HIV infection, and elevated frequencies of these cells correlated with relative viral control. These cells had an effector memory or end effector phenotype and expressed CXCR5. HIV-specific CD8(+) T cells exhibited high levels of IL-21R, indicating sensitivity to IL-21. Low or aviremic long-term nonprogressors, however, showed absent or low HIV-specific IL-21 CD4(+) T cells, but more easily detectable HIV-specific IL-2-producing CD4(+) T cells, suggesting changing requirements for particular gamma-chain cytokines depending on Ag abundance. Thus, IL-21-producing CD4(+) T cells are induced in viremic HIV infection and likely contribute to viral control by affecting CD8(+) T cell maintenance.
Clinical Sciences Division, St. Michael's Hospital, University of Toronto, Canada.
Feng Yun
FY
Yue
Calvin
C
Lo
Ali
A
Sakhdari
Erika Yue
EY
Lee
Colin M
CM
Kovacs
Erika
E
Benko
Jun
J
Liu
Haihan
H
Song
R Brad
RB
Jones
Prameet
P
Sheth
Duncan
D
Chege
Rupert
R
Kaul
Mario A
MA
Ostrowski
D000208:Acute Disease; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology / Q000821:virology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology / Q000821:virology; D002908:Chronic Disease; D018450:Disease Progression; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000473:pathology / Q000821:virology*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D007156:Immunologic Memory; D016130:Immunophenotyping; D007378:Interleukins / Q000096:biosynthesis*; D008213:Lymphocyte Activation / Q000276:immunology*; D019562:Viral Load / Q000276:immunology; D000098546:Interleukin-21
D018984:Epitopes, T-Lymphocyte; D007378:Interleukins; D000098546:Interleukin-21