Characterization of maturation and function of natural killer cells in xenogeneic (rat-->mouse) bone marrow chimeras. Evidence that rat NK cells are present and functional in a xenogeneic environment.

Reconstitution of B10 recipient mice, conditioned with total body irradiation (950 rads), with 40×10 6 untreated F344 or WF rat bone marrow cells results in stable rat stem-cell engraftment with multilineage lymphohematopoietic chimerism. We have now characterized NK cell generation, maturation, and function in fully xenogeneic chimeras (WF rat→B10 mouse; F344→B10 mouse). Early during xenogeneic reconstitution, rat-derived NK cells predominated in splenic lymphoid tissue, composing 14-18% of total cells at week 1 and increasing to 95.6-59.9% of total cells at week 2