Early regeneration of thymic progenitors in rhesus macaques infected with simian immunodeficiency virus.
The thymus plays a critical role in the maturation and production of T lymphocytes and is a target of infection by human immunodeficiency virus (HIV) and the related simian immunodeficiency virus (SIV). Using the SIV/macaque model of AIDS, we examined the early effects of SIV on the thymus. We found that thymic infection by SIV resulted in increased apoptosis 7-14 d after infection, followed by depletion of thymocyte progenitors by day 21. A marked rebound in thymocyte progenitors occurred by day 50 and was accompanied by increased levels of cell proliferation in the thymus. Our results demonstrate a marked increase in thymic progenitor activity very early in the course of SIV infection, long before marked declines in peripheral CD4(+) T cell counts.
Wykrzykowska
J J
JJ
New England Regional Primate Research Center, Harvard Medical School, Southborough, Massachusetts 01772, USA.
Rosenzweig
M
M
Veazey
R S
RS
Simon
M A
MA
Halvorsen
K
K
Desrosiers
R C
RC
Johnson
R P
RP
Lackner
A A
AA
D000818:Animals; D017209:Apoptosis; D002455:Cell Division; D008253:Macaca mulatta; D008297:Male; D012038:Regeneration; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000473:pathology* / Q000821:virology; D015302:Simian Immunodeficiency Virus; D013234:Stem Cells; D013950:Thymus Gland / Q000276:immunology / Q000473:pathology* / Q000821:virology