Molecular characterization of feline interleukin 16: Chemotactic activity and effect on feline immunodeficiency virus infection and/or replication

Interleukin 16 (IL-16) has been shown to diminish HIV and SIV replication t hrough inhibition of HIV and SN mRNA transcription. To evaluate its role in the FIV cat model, we cloned and expressed feline LL-16 and determined its ability to induce chemotaxis as well as to inhibit FN replication in cultu red PBMCs. Sequence comparison of rfIL-16 with human, African green monkey, rhesus macaque, and mouse IL-16 showed 84.2, 84.5, 84.4, and 79.4% identit y at the nucleotide sequence level and 93, 91.5, 90.7, and 87.2% identity a t the amino acid sequence level? respectively. Biocharacterization of rfIL- 16 revealed potent induction of chemotaxis (p < 0.05), In addition, p24 pro duction from feline PBMCs infected with FIV Zurich 2 in vitro was decreased up to 87% (p < 0.05), These data demonstrate biologic and antiviral functi onality of rfIL-16.