title: Idiopathic CD4+ T lymphocytopenia is associated with increases in immature/transitional B cells and serum levels of IL-7.
abstract: Idiopathic CD4+ T lymphocytopenia (ICL) is a rare heterogeneous disorder defined by CD4+ T-cell counts below 300 cells/muL in the absence of human immunodeficiency virus (HIV) infection or other known immune deficiency disorders. Here, we report the expansion of immature/transitional B cells in patients with ICL, which is associated with elevated serum levels of IL-7. Both the percentage of immature/transitional B cells and levels of IL-7 were inversely correlated with levels of CD4+ T-cell counts and directly correlated to each other. Further analyses of B cells indicated that, in contrast to the activating effects of HIV disease on mature B cells, the expansion of immature/transitional B cells in patients with ICL occurred at the expense of memory B cells. These findings extend previous reports on primary immunodeficiencies as well as HIV disease by suggesting that CD4+ T-cell lymphopenia has an impact on human B-cell development either directly or indirectly via the associated elevation of IL-7 levels.
authors.affiliation: Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Malaspina
authors.forename: Susan
authors.initials: S
authors.lastname: Moir
authors.forename: Doreen G
authors.initials: DG
authors.lastname: Chaitt
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Rehm
authors.forename: Shyam
authors.initials: S
authors.lastname: Kottilil
authors.forename: Judith
authors.initials: J
authors.lastname: Falloon
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Fauci
mesh_terms: D001402:B-Lymphocytes / Q000378:metabolism* / Q000473:pathology*; D002454:Cell Differentiation; D006801:Humans; D015851:Interleukin-7 / Q000097:blood*; D018344:T-Lymphocytopenia, Idiopathic CD4-Positive / Q000378:metabolism* / Q000473:pathology*
chemical_list: D015851:Interleukin-7