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.

A natural CCL5/RANTES variant antagonist for CCR1 and CCR3.

The N-terminal domain of the chemokine CCL5/regulated upon activation normal T cell expressed and secreted (RANTES) has been shown to be critical for its biological activity on leukocytes. Several N-terminus-modified CCL5/RANTES derivatives, such as N-Terminal truncated CCL5/RANTES, Met-RANTES, and amino-oxypentane (AOP)-RANTES exhibited antagonist or partial agonist functions when investigated on the properties of their receptors CCR1, CCR3, and CCR5. Studying 95 African samples from Cameroon, we found a naturally occurring variant of CCL5/RANTES containing a missense mutation located in the first amino acid of the secreted form (S24F).

Influence of the R22H variant of macrophage inflammatory protein 1beta/Lag-1 in HIV-1 survival.

The chemokine macrophage inflammatory protein 1beta/CCL4, ligand of the major HIV co-receptor CCR5, is encoded by two genes, Act-2 and Lag-1. Our work focused on R22H, a variant of Lag-1 located near the N-loop, in the 310 turn, a domain essential for interacting with CCR5. We observed that HIV-1-infected patients from the SEROCO cohort, bearing the R22H variant either at the homozygous or heterozygous state, exhibit a worse global survival compared with wild-type homozygous individuals.

Biochemical and HIV-1 coreceptor properties of K26R, a new CCR5 Variant in China's Sichuan population.

Despite multiple exposures to HIV-1, some individuals remain uninfected. This resistance to HIV infection has been associated with homozygosity for a 32-basepair deletion in the CCR5 receptor gene. This variant is frequent in caucasians but extremely rare in Asians and Africans.

New CCR5 variants associated with reduced HIV coreceptor function in southeast Asia.

Background: Despite multiple exposure to HIV-1, some individuals remain uninfected. This resistance has been associated with homozygosity for a 32 base pair deletion in the gene for the CCR5 receptor. This variant occurs frequently in Caucasians but is extremely rare in Asians or Africans.