Evaluation of CD4+ T cell function In vivo in HIV-infected patients as measured by bacteriophage phiX174 immunization.
Bacteriophage phiX174 immunization was used to measure CD4(+) T cell function in vivo in human immunodeficiency virus (HIV)-infected patients across all disease stages. Function was evaluated by measuring the ability of T cells to provide help to B cells in antibody production, amplification, and isotype switching. A total of 33 patients and 10 controls received 3 bacteriophage phiX174 immunizations 6 weeks apart. The patients' responses regarding bacteriophage-specific total antibody titers and IgG titers were quantitatively and qualitatively inferior to the controls' responses. Overall, 7 of 33 patients had normal T cell function. Baseline CD4 counts provided the strongest correlation with total antibody and IgG titers. HIV RNA had a weaker association with responses but had some predictive power among patients with a CD4 count >200 cells/microL. Bacteriophage phiX174 immunization seems to be a useful tool for measuring immune function in vivo, which suggests that most HIV-infected patients may have abnormal CD4(+) T cell function despite adequate antiretroviral treatment.
Biologic Consulting, Inc., Edgewater, MD 21037, USA. ilanafog@aol. com
I
I
Fogelman
V
V
Davey
H D
HD
Ochs
M
M
Elashoff
M B
MB
Feinberg
J
J
Mican
J P
JP
Siegel
M
M
Sneller
H C
HC
Lane
D000293:Adolescent; D000328:Adult; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D010584:Bacteriophage phi X 174 / Q000276:immunology; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D020276:HIV Long-Term Survivors; D006801:Humans; D017578:Immunoglobulin Class Switching; D007156:Immunologic Memory; D008297:Male; D016176:T-Lymphocyte Subsets; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014611:Vaccination