Generation of cytotoxic T lymphocytes against TNP-haptenated syngeneic cells in microcultures: The effect of nude spleen cells as accessory cells

Abstract

The present experiments analyzed the possibility of using nude spleen cells in microcultures as accessory cells for cytotoxic T lymphocytes (CTL) responses against major histocompatibility complex (MHC)-compatible stimulator cells. CTL responses of CBA lymph node cells against trinitrophenyl (TNP)-haptenated syngeneic stimulator cells were easily obtained with MHC-compatible nude spleen cells as accessory cells and no additional source of help. Peripheral lymphocytes from C57BL/6 mice or CBA thymocytes responded against TNP-haptenated syngeneic stimulator cells only in the presence of MHC-incompatible but not MHC-compatible nude spleen cells. Our experiments excluded the possibility that the negative results with MHC-compatible nude spleen cells resulted from a lack of CTL-precursor cells with appropriate specificity, or from a general deficiency of the nude spleen cells under test. The experiments suggested instead that the unresponsive systems contained insufficient numbers of helper T cells with appropriate specificity or that the unresponsive systems might have been suppressed. MHC-incompatible nude spleen accessory cells mediated detectable responses in all systems under test but were in some cases less effective than other helper components in control cultures. More detailed experiments on systems with an obligatory requirement for MHC incompatibility revealed that MHC disparity was not recognized by cells in the nude spleen cell population. The accessory function of the MHC-incompatible nude spleen cells was radiation sensitive.