Feline peripheral blood mononuclear cells express message for both CXC andCC type chemokine receptors

The feline immunodeficiency virus (FIV) causes a disease in cats similar in clinical presentation and disease progression to that of HIV and AIDS. It is now known that, for HIV infection, as well as primary binding of virus t o the CD4 receptor, entry and infection of cells requires coreceptors which are members of the chemokine group of G-protein coupled receptors. Because of the similarity of HIV and FIV, we hypothesised that coreceptors are req uired for the entry and infection of cells by FIV. Using a feline cDNA libr ary derived from a feline IL-2 sensitive lymphocyte cell line, we identifie d the presence of message for both CC and CXC chemokine receptors. The feli ne CXCR4 has been shown to facilitate fusion by FIV [44] and we suggest tha t the feline CCR5 receptor mediates infection of feline cells by M-tropic s trains of FIV.