Secondaryin vitrostimulation of specific cytotoxic cells to newcastle disease virus in chickens

Previous work on cell-mediated cytotoxicity in the chicken has relied on in vivo techniques for the generation of a heterogeneous population of effector cells that are assayed for cytotoxicity directly following removal from the bird. In this work, spleen cells were removed from NDV-primed chickens and restimulated in vitro for 5 to 6 days. This gave rise to a non-adherent population of effector cells that were capable of rapidly lysing NDV-labelled target cells, as measured in a 51Cr-release assay. These results are broadly similar to those gained in parallel experiments with mice, where a classical cytotoxic T cell response is evoked. In the light of these observations, it is considered possible that the avian effector cell may also be a T cell.