Prevent the prevent the spread of the HIV virus to other cell
Despite multiple exposures to HIV, a small number of people do
not develop AIDS and show no evidence of HIV-infected cells.
Comparing their genes with the genes of infected individuals, researchers discovered that resistant individuals have an unusual form
of a gene that codes for an immune cell-surface protein called CCR5.
Further work showed that HIV binds to the main protein receptor
(CD4) on an immune cell, but on most cell types, HIV also needs to
bind to CCR5 as a “co-receptor” to infect the cell (below, left). An absence of CCR5 on the cells of resistant individuals, due to the gene
alteration, prevents the virus from entering the cells
WHY IT MATTERS Researchers have been searching for drugs to block
cell-surface receptors involved in HIV infection. The main receptor
protein, CD4, performs many important functions for cells, so interfering with it could cause dangerous side effects. The Discovery of the CCR5
co-receptor provided a safer target for the development of drugs that mask
CCR5 and block HIV entry. One such drug, maraviroc (brand name
Selzentry), was approved for the treatment of HIV infection in 2007.
