Viral protein sythesis by tissues from avian leukosis virus-infected chickens. II. Effect of passive neutralizing antibody in normal and agammaglobulinaemic chickens.

Synthesis in vitro of avian leukosis virus (ALV) group (gs proteins, p27 and p12, by various tissues from chickens infected within a few days after hatching was studied by means of autoradiography of immunoelectrophoretic patterns. Viral protein was synthesized in all tissues of chicks examined between days 18 and 50 of age after which time liver, kidney, bursa, thymus, and spleen became negative. The lung and genital organs of the chicks, however, continued to synthesize viral protein up to 100 days of age, when the experiment was ended. Repeated injections of neutralizing chicken antibody to ALV (Ab) starting on day 26 or 37 caused gs protein to decrease in spleen, liver, and thymus within 5 days but not in bursa, lung, and genital organs. Agammaglobulinaemic (Agamma) chickens showed prolonged persistence of gs protein synthesis in the spleen and liver; this synthesis was abrogated by passive Ab. Liver from Agamma chickens, however, also became negative without Ab treatment. The relative roles of antibody and cellular immunity in influencing ALV replication during the initial phase of infection before lymphoma development are discussed.