Cellular immune response in HIV-infected patients with histoplasmosis.
The relationship of immunity to Histoplasma capsulatum and CD4 count in HIV-1-infected patients is unknown. Samples of blood from people with HIV infection and from HIV-negative volunteers were assessed for immune responsiveness to the histoplasmin antigen using proliferation and interferon-gamma production as indicators of immunity. Results of histoplasmin skin tests, lymphoproliferative responses (LPR), and interferon-gamma production were positive in 9 of 20 (45%) HIV-negative controls, and in vitro measurements agreed highly with skin test reactivity. Among HIV-1-infected patients with recent histoplasmosis, skin test results were positive in none, LPR results were positive in 14%, and interferon-gamma production in 18%. Among HIV-1-infected patients with CD4 counts between 200 and 500 cells/mm(3), LPR was positive in 8% and interferon-gamma production in 33%, and among those with CD4 counts >500 cells/mm(3), LPR was positive in 31% and interferon-gamma production in 46%. In conclusion, immune responsiveness to H. capsulatum was depressed in HIV-1-infected persons with CD4 counts between 200 and 500 cells/mm(3), but approached normal in those with CD4 counts >500 cells/mm(3).
Vail
G Matthew
GM
Indiana University School of Medicine, Histoplasmosis Reference Laboratory, Richard L. Roudebush Veterans Administration Hospital, Indianapolis, Indiana, USA.
Mocherla
Satish
S
Wheat
L Joseph
LJ
Goldberg
Janet
J
Camp
April
A
Brizendine
Edward
E
Schnizlein-Bick
Carol
C
D018791:CD4 Lymphocyte Count; D002455:Cell Division; D015331:Cohort Studies; D015658:HIV Infections / Q000150:complications / Q000276:immunology*; D015497:HIV-1; D006659:Histoplasmin / Q000276:immunology; D006660:Histoplasmosis / Q000150:complications / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000032:analysis; D007963:Leukocytes, Mononuclear / Q000276:immunology; D012882:Skin Tests
D007371:Interferon-gamma; D006659:Histoplasmin