Increased production of IL-7 accompanies HIV-1-mediated T-cell depletion: implications for T-cell homeostasis.
We hypothesized that HIV-1-mediated T-cell loss might induce the production of factors that are capable of stimulating lymphocyte development and expansion. Here we perform cross-sectional (n = 168) and longitudinal (n = 11) analyses showing that increased circulating levels of interleukin (IL)-7 are strongly associated with CD4+ T lymphopenia in HIV-1 disease. Using immunohistochemistry with quantitative image analysis, we demonstrate that IL-7 is produced by dendritic-like cells within peripheral lymphoid tissues and that IL-7 production by these cells is greatly increased in lymphocyte-depleted tissues. We propose that IL-7 production increases as part of a homeostatic response to T-cell depletion.
Napolitano
L A
LA
Gladstone Institute of Virology and Immunology, San Francisco General Hospital, and Department of Medicine, University of California at San Francisco, San Francisco, California 94110-9100, USA.
Grant
R M
RM
Deeks
S G
SG
Schmidt
D
D
De Rosa
S C
SC
Herzenberg
L A
LA
Herndier
B G
BG
Andersson
J
J
McCune
J M
JM
D015331:Cohort Studies; D018450:Disease Progression; D015658:HIV Infections / Q000473:pathology; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D015851:Interleukin-7 / Q000096:biosynthesis*; D008137:Longitudinal Studies; D008212:Lymphocyte Depletion; D008221:Lymphoid Tissue / Q000378:metabolism / Q000821:virology; D013601:T-Lymphocytes / Q000166:cytology*
D015851:Interleukin-7