Effects of chicken anemia virus on cell-mediated immune function in chickens exposed to the virus by a natural route.

Three-week-old chicks were inoculated orally with CAV and killed at various times postinoculation (PI). The spleens were removed, the cells were stimulated with concanavalin A, and lymphocyte transformation responses were determined. Supernatants from these cultures were also assayed for T-cell growth factor (TCGF) and interferon. Adherent macrophages from spleen or bone marrow were assayed for interleukin-1 production, Fc receptor expression, phagocytosis, and bactericidal activity. All CAV-inoculated chickens developed CAV antibodies, but no anemia was seen. Controls remained CAV-antibody-negative throughout the experiment. CAV-inoculated chickens showed significant differences from controls in their lymphocyte transformation responses and in production of TCGF and interferon. Differences were greatest at 14, 21, and 28 days PI. Significant differences were also observed in interleukin-1 production by spleen macrophages, as well as in Fc receptor expression, phagocytosis, and bactericidal activity of bone-marrow macrophages.