CC-chemokines enhance the replication of T-tropic strains of HIV-1 in CD4(+) T cells: role of signal transduction.

This study demonstrates that several CC-chemokines, including those that inhibit entry and replication of macrophage-tropic strains of HIV, increase the replication of T cell (T)-tropic strains in CD4(+) T cells. Enhancement of T-tropic HIV replication is observed at early stages of replication, requires signaling through inhibitory guanine nucleotide-binding regulatory (Gi) proteins, and is associated with increased cell surface colocalization of CD4 and the T-tropic HIV coreceptor CXCR4. These findings may further our understanding of the factors that influence the replication and spread of T-tropic strains of HIV in vivo and suggest that the use of cell signaling CC-chemokines as therapeutic agents for the purpose of limiting HIV replication in vivo should be approached with caution.