Transgenic Mice: New Systems for Studying the Function of MHC Class II Molecules

Transgenic mice have great potential as systems for studying the function of major histocompatibility complex class II molecules. Several mouse lines that bear a wild-type E alpha transgene have been created and characterized. The transgene is expressed efficiently, accurately, and with tissue-and cell type-specificity. The recipient (E alpha negative) strain is endowed with new immunological capabilities; namely, it can now respond to E-restricted antigens. Other transgenic lines have been created by injecting E alpha clones that harbor promoter deletions. These mice display novel patterns of E alpha expression eg absent on B cells, but present on peripheral macrophages and in the thymus; or absent in the thymic cortex but present in the medulla. These mice may provide new insights into tolerance induction, MHC restriction etc.