Expression of CD28 on CD8+ and CD4+ lymphocytes during HIV infection.
CD28 interaction with B7 molecules, expressed on the membranes of antigen-presenting cells, co-stimulates cytokine production, T-cell proliferation and generation of cytotoxic lymphocytes. The expression of CD28 markers on CD4+ and CD8+ lymphocytes was studied in a group of subjects at various stages of HIV infection. A reduction in the percentage of CD28-bearing CD4+ and CD8+ cell subsets was observed during the asymptomatic stage of the disease. This reduction was more pronounced in AIDS than in non-AIDS patients. At the same time, an increase in the absolute CD8+CD28- cell number (greater in stage A than in stage B and C subjects) was observed in HIV-infected patients. The finding of an altered pattern of CD28 expression on T cells might per se explain certain early defects in the cytokine pattern and in the immune response peculiar to HIV-infected patients.
Caruso
A
A
Institute of Microbiology, University of Brescia, Italy.
Cantalamessa
A
A
Licenziati
S
S
Peroni
L
L
Prati
E
E
Martinelli
F
F
Canaris
A D
AD
Folghera
S
S
Gorla
R
R
Balsari
A
A
D018106:CD28 Antigens / Q000096:biosynthesis*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping
D018106:CD28 Antigens