CD38 expression on CD8 T cells has a weak association with CD4 T-cell recovery and is a poor marker of viral replication in HIV-1-infected patients on antiretroviral therapy.
OBJECTIVE
The aim of the study was to determine whether the expression of CD38 on CD8 T cells can identify patients with virological failure on antiretroviral therapy (ART).


METHODS
This was a cross-sectional study of patients attending a single HIV clinic in London.


METHODS
The expression of CD38 on CD8 T cells was assessed using a biologically calibrated flow cytometry protocol. Patients were characterized by lymphocyte subset and viral load measurements. Characteristics including historical CD4 T cell counts, therapeutic history, co-infections and demographics were obtained from medical records.


RESULTS
Elevated levels of CD8 CD38(high) T cells were found in HIV-1-infected patients who failed to suppress viral replication with ART; however, this parameter lacked sufficient sensitivity and specificity to replace viral load testing in assessing the efficacy of ART. Increased levels of CD8 CD38(high) cells were associated with reduced CD4 T cell counts in HIV-1-infected patients on ART after correcting for known determinants of CD4 T-cell recovery.


CONCLUSIONS
The expression of CD38 on CD8 T cells lacks sufficient sensitivity and specificity to be used as a surrogate marker for viral load to monitor HIV-1 infection. T-cell activation is associated with reduced CD4 T-cell reconstitution in patients receiving ART.
Steel
A
A
Department of Immunology, Imperial College, Chelsea & Westminster Hospital, London, UK.
John
L
L
Shamji
M H
MH
Henderson
D C
DC
Gotch
F M
FM
Gazzard
B G
BG
Kelleher
P
P
D051997:ADP-ribosyl Cyclase 1 / Q000378:metabolism*; D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology* / Q000821:virology; D015497:HIV-1; D006801:Humans; D008131:London; D008297:Male; D017211:Treatment Failure; D014779:Virus Replication / Q000187:drug effects / Q000276:immunology
D051997:ADP-ribosyl Cyclase 1