FIV p24 Background Information Feline immunodeficiency virus (FIV) is a lentivirus that affects domestic cats throughout the world. Five subtypes of FIV exist, based on amino acid sequence differences in the the viral envelope. The main mode of FIV transmission is through deep bite wounds, though it can also be spread via mucosal surfaces such as those in the mouth, rectum and vagina. FIV is similar to human immunodeficiency virus (HIV) in that it infects many cell types in its host, including CD4+ and CD8+ T lymphocytes, B lymphocytes and macrophages. FIV eventually leads to collapse of the immune system because of the infection and exhaustion of the CD4+ cells. FIV p120 and p24 are glycoproteins that localize to the envelope of the virus and are useful in diagnosis of the disease.
