ERVW-1 and neoplasm: To determine the kinetics of T-cell responses in this tumor rejection model, we quantified the population of FV-specific effector CD8+ T cells by staining lymphocytes from draining (drLN) and non-draining lymph nodes (non-drLN) of FBL-3-challenged mice with H-2DbgagL MHC class I tetramers [9, 20] or MHC class II tetramers loaded with the H-2I-Ab-restricted CD4+ T-cell epitope H19-Env [20].