Reduced CD4 T cell activation and in vitro susceptibility to HIV-1 infection in exposed uninfected Central Africans.
BACKGROUND
Environmentally driven immune activation was suggested to contribute to high rates of HIV-1 infection in Africa. We report here a study of immune activation markers and susceptibility to HIV-1 infection in vitro of forty-five highly exposed uninfected partners (EUs) of HIV-1 infected individuals in Central African Republic, in comparison with forty-four low-risk blood donors (UCs).


RESULTS
Analysis of T lymphocyte subsets and activation markers in whole blood showed that the absolute values and the percentage of HLA-DR+CD4 T cells and of CCR5+CD4 T cells were lower in the EUs than in the UCs (p = 0.0001). Mutations in the CCR5 coding region were not found in either group. Susceptibility to in vitro infection of unstimulated peripheral blood mononuclear cells, prior of PHA activation, was decreased in EUs compared to UCs, either using a CXCR4-tropic or a CCR5-tropic HIV-1 strain (p = 0.02 and p = 0.05, respectively). Levels of MIP-1beta, but not of MIP-1alpha or RANTES, in the supernatants of PHA-activated PBMC, were higher in the EUs than in the UCs (p = 0.007).


CONCLUSIONS
We found low levels of CD4 T cell activation and reduced PBMC susceptibility to HIV-1 infection in Central African EUs, indicating that both may contribute to the resistance to HIV-1 infection.
Bégaud
Evélyne
E
Institut Pasteur, Bangui, CAR. ebegaud@pasteur.fr
Chartier
Loïc
L
Marechal
Valéry
V
Ipero
Julienne
J
Léal
Josianne
J
Versmisse
Pierre
P
Breton
Guillaume
G
Fontanet
Arnaud
A
Capoulade-Metay
Corinne
C
Fleury
Hervé
H
Barré-Sinoussi
Françoise
F
Scott-Algara
Daniel
D
Pancino
Gianfranco
G
D000293:Adolescent; D000328:Adult; D000350:Africa, Central; D015415:Biomarkers / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5 / Q000097:blood; D019742:Chemokines, CC / Q000097:blood / Q000378:metabolism; D005260:Female; D018023:HIV Seronegativity / Q000276:immunology*; D015497:HIV-1; D006684:HLA-DR Antigens / Q000097:blood; D006801:Humans; D007113:Immunity, Innate; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000821:virology; D008213:Lymphocyte Activation; D019402:Macrophage Inflammatory Proteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D019713:Receptors, CCR5 / Q000097:blood / Q000235:genetics
D015415:Biomarkers; C066507:CCL4 protein, human; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D019742:Chemokines, CC; D006684:HLA-DR Antigens; D019402:Macrophage Inflammatory Proteins; D019713:Receptors, CCR5