title: Turnover rates of B cells, T cells, and NK cells in simian immunodeficiency virus-infected and uninfected rhesus macaques.
abstract: We determined average cellular turnover rates by fitting mathematical models to 5-bromo-2'-deoxyuridine measurements in SIV-infected and uninfected rhesus macaques. The daily turnover rates of CD4(+) T cells, CD4(-) T cells, CD20(+) B cells, and CD16(+) NK cells in normal uninfected rhesus macaques were 1, 1, 2, and 2%, respectively. Daily turnover rates of CD45RA(-) memory T cells were 1%, and those of CD45RA(+) naive T cells were 0.5% for CD4(+) T cells and approximately 1% for CD4(-)CD45RA(+) T cells. In SIV-infected monkeys with high viral loads, the turnover rates of T cells were increased approximately 2-fold, and that of memory T cells approximately 3-fold. The turnover of CD4(+)CD45RA(+) naive T cells was increased 2-fold, whereas that of CD4(-)CD45RA(+) naive T cells was marginally increased. B cells and NK cells also had increased turnover in SIV-infected macaques, averaging 3 and 2.5% per day, respectively. For all cell types studied here the daily turnover rate increased with the decrease of the CD4 count that accompanied SIV infection. As a consequence, the turnover rates of CD4(+) T cells, CD4(-) T cells, B cells, and NK cells within each monkey are strongly correlated. This suggests that the cellular turnover of different lymphocyte populations is governed by a similar process which one could summarize as "generalized immune activation." Because the viral load and the CD4 T cell count are negatively correlated we cannot determine which of the two plays the most important role in this generalized immune activation.
authors.affiliation: Theoretical Biology, Utrecht University, Utrecht, The Netherlands. R.J.DeBoer@bio.uu.nl
authors.forename: Rob J
authors.initials: RJ
authors.lastname: De Boer
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mohri
authors.forename: David D
authors.initials: DD
authors.lastname: Ho
authors.forename: Alan S
authors.initials: AS
authors.lastname: Perelson
mesh_terms: D000818:Animals; D016175:B-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D001973:Bromodeoxyuridine / Q000378:metabolism; D002453:Cell Cycle / Q000276:immunology*; D016923:Cell Death / Q000276:immunology; D005434:Flow Cytometry / Q000706:statistics & numerical data; D007156:Immunologic Memory; D007399:Interphase / Q000276:immunology; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008213:Lymphocyte Activation; D018655:Lymphocyte Count / Q000706:statistics & numerical data; D016131:Lymphocyte Subsets / Q000166:cytology* / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D008253:Macaca mulatta; D018448:Models, Immunological; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000473:pathology*; D015302:Simian Immunodeficiency Virus / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism / Q000473:pathology
chemical_list: D001973:Bromodeoxyuridine