CUTTING EDGE - GENETIC-VARIATION AMONG 129 SUBSTRAINS - PRACTICAL CONSEQUENCES

We designed a series of experiments to define the role of IFN-gamma in cellular interactions mediating graft rejection by assessing the reje ction of H-Y disparate grafts in both ligand and receptor knockout mic e and their control inbred strain. In the course of these studies it b ecame apparent that neither knockout strain is histocompatible with th e putative control and that the putative control is not histocompatibl e with either knockout strain. In the profess of deducing why this mig ht be so, it became apparent that the putative control is not an inbre d strain of mouse. Thus, in the absence of rigorous genetic control, t he utility of such knockout strains of mice for assessing the effects of cytokines and receptors in transplantation and autoimmunity is limi ted.