[Chemokines and immunomodulation: applications for HIV infections]

The genetic control of HIV infection by the host involves a certain number of genes, among which those which code for chemokines/chemokines receptors, cytokines, MHC. Genes such as CCR5, CCR2, SDF1, and more recently CX3CR1 received great attention from several laboratories including ours, since they play a role as HIV coreceptor and, as such, on the infectivity of the host. In addition, it was shown that the polymorphism of these genes influences the evolution of infection, whether they have a protective or deleterious effect. Results obtained by our laboratory on the genetic polymorphism and its implication in HIV infection will be reported herein. Furthermore, to better understand their role, we looked for the capacities that the chemokines may have to play an immunomodulatory function, independently of their chemoattractive effect. In two examples, we showed that chemokines influence notably the cellular immune functions, such as CD8 cytotoxicity (Rantes/CCR3) and gamma interferon production (fractalkine/CX3CR1). Globally, the results indicate that chemokines/chemokines receptors polymorphism represent important epidemiological factors, but also contributes to evaluate the prognosis of HIV infection, through a better understanding of the disease physiopathology.