Effect of Interleukin-12 and Interleukin-10 on the Virus Replication and Apoptosis in T-Cells Infected with Feline Immunodeficiency Virus

Abstract

Interleukin-12 (IL-12) is an important cytokine for Thl response which stimulates the T-cell population to produce cytokines for cellular immunity. Interleukin-10 (IL-10) is a pleiotropic cytokine capable of suppressing cytokine production from macrophages and T-cells and participates in Th2 immune response. The present study was carried out to examine the effect of these cytokines on virus replication and apoptosis in T-cells infected with feline immunodeficiency virus (FIV). Infection of a feline T-lymphoid cell line (Fel-039) resulted in an increase of the reverse transcriptase (RT) activity in the culture supernatant accompanied by cell death from apoptosis. Addition of human recombinant IL-12 significantly inhibited the virus replication and apoptosis in Fel-039 cells in a dose dependent manner. Furthermore, the antiviral activity of IL-12 was associated with the expression of IFN-γ in the FIV-infected Fel-039 cells. In contrast, human recombinant IL-10 did not show any inhibitory effect on the virus replication and apoptosis in the Fel-039 cells infected with FIV. These results suggest that the inhibitory effect of IL-12 on both virus replication and apoptosis has potential implications for the design of immunotherapy strategies using IL-12 in FIV infection.