CD28 costimulation and T lymphocyte proliferative responses in HIV-1 infection.
To investigate whether defective costimulatory signals could be involved in the loss of T lymphocyte functions during HIV-1 infection, we tested the effect of CD28 costimulation on both T cell receptor/CD3 and HIV-1 antigen-induced proliferative responses. Although CD3-mediated responses significantly decreased with more advanced stages of HIV-1 infection, the ability of potentiating the responses through CD28 costimulation was maintained at all stages and did not differ from that of HIV-1- subjects. When CD28 costimulation was studied in lymphocyte cultures stimulated with HIV-1 gp160 or p24, potentiation was seen only when a significant response was present without additional CD28 triggering, namely in subjects receiving active immunization with recombinant gp160. These results confirm the integrity of the CD28 pathway of costimulation during HIV-1 infection, and suggest that lymphocytes responding to soluble HIV-1 antigen are not deleted in HIV-1-infected patients, but do not receive significant priming during the natural course of the infection.
Carlesimo
M
M
Department of Clinical Medicine, University of Rome La Sapienza, Italy.
Pontesilli
O
O
Varani
A R
AR
Bernardi
M L
ML
Mazzone
A M
AM
Rosso
R
R
Guerra
E C
EC
Cassone
A
A
Paganelli
R
R
Aiuti
F
F
D018106:CD28 Antigens / Q000276:immunology*; D017252:CD3 Complex / Q000276:immunology; D002455:Cell Division; D002478:Cells, Cultured; D016655:HIV Core Protein p24 / Q000276:immunology; D019302:HIV Envelope Protein gp160 / Q000276:immunology; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1; D006801:Humans; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D014611:Vaccination
D018106:CD28 Antigens; D017252:CD3 Complex; D016655:HIV Core Protein p24; D019302:HIV Envelope Protein gp160