Electrophoresis of proteins of irradiated mouse chimeras.

A comparative study was made of the proteins in various tissues of Sprague-Dawley rats and (101 x C3H)F/sub 1/ mice. The results were used as a basis for studying changes in the protein patterns in tissues of rat-mouse chimeras: i.e., (101 x C3H)F/sub 1/ mice were given 950 r of x rays and then received an injection of bone marrow from Sprague-Dawley rats. Electrophoretic mobilities of rat proteins extracted from the bone marrow, spleen, lymph node, and thymus of chimeras and rats were similar. The quantity of rat proteins and the rate and time at which they appeared in different hematopoietic organs were quite different. Some mouse-type proteins not found in chimera tissues examined 30 days after treatment were frequently present on the 50th day or later, which suggests regression of the graft. The results are consistent with the idea that rat-type proteins synthesized in the cytoplasm of transplanted rat cells are controlled by the genotype of these cells, even in a mouse environment. They also indicate that there are organ-specific differences, in the rate and degree of replacement of transplanted cells, that require further investigation. (auth)