SYNGENEIC LYSIS OF RETICULOENDOTHELIOSIS VIRUS-TRANSFORMED CELL-LINES TRANSFECTED WITH MAREKS-DISEASE VIRUS GENES BY VIRUS-SPECIFIC CYTOTOXIC T-CELLS

Cell-mediated immune responses against Marek's disease virus (MDV) antigens were examined using reticuloendotheliosis virus (REV)-transformed cell lines of two haplotypes ((BB19)-B-19 and (BB13)-B-13). These cell lines were stably transfected with cloned fragments of MDV DNA resulting in the expression of the MDV-specific phosphoprotein pp38. Effector cells were obtained from P2a ((BB19)-B-19) and S13 ((BB13)-B-13) chickens at 7 days post inoculation with REV, oncogenic or attenuated serotype 1 MDV (JM-16/O and JM-16/A, respectively), serotype 2 MDV (SB-1), or herpesvirus of turkeys (HVT). Transfection of MDV genes did not influence the expression of Class I major histocompatibility complex antigens. The optimal effector to target cell ratio was determined to be 100:1. REV-sensitized effector cells lysed REV cell lines and REV cell lines transfected with MDV DNA in a syngeneic fashion. Effector cells from chickens inoculated with JM-16/O, JM16/A, SB-1 or HVT lysed only the syngeneic, transfected cell lines, but not the parent REV cell lines. The percentage specific release caused by the MDV-sensitized effector cells was low, but statistically significant.