LISTERIA MONOCYTOGENES-INFECTED HEPATOCYTES ARE TARGETS OF MAJOR HISTOCOMPATIBILITY COMPLEX CLASS IB RESTRICTED ANTILISTERIAL CYTOTOXIC T-LYMPHOCYTES

Subclinical infection of BALB/c mice with the intracellular bacterial pathogen Listeria monocytogenes results in the development of protecti ve antilisterial immunity. L. monocytogenes can infect hepatocytes, an d antilisterial cytotoxic T lymphocytes (CTL) lyse Listeria-infected h epatocytes in a major histocompatibility complex (MHC) class Ia-restri cted manner. It remained to be determined whether L. monocytogenes-inf ected hepatocytes are susceptible to MHC class rb-restricted cytolysis . In this study, we showed that hepatocytes express MHC class Ib molec ule Qa-1(b) mRNA and protein. We further showed that Listeria-infected hepatocytes are susceptible to MHC class Ib-restricted cytolysis, sin ce C57BL/6-derived Listeria-infected hepatocytes were lysed by BALB/c- derived antilisterial CTL. These results establish that Listeria-infec ted hepatocytes are susceptible to cytolysis by MHC class Ib restricte d Listeria-specific CTL.