Abstract: | SYNOPSIS. Development of Trypanosoma lewisi in chimaeric mice with and without rat serum supplements was studied in 5 protocols. Chimaeric mice were male and female C3H/An Cum and 1C3F1, [(101/CUM × C3H/An Cum) F1] exposed to 950-1000 R of whole-body X-irradiation. Their hemopoietic systems were replaced with Sprague-Dawley rat bone marrow. Trypanosomes did not develop in any mice not supplemented with rat serum. Ih those chimaeric and normal mice given rat serum the trypanosomes grew and developed large populations, more so in chimaeric than in normal animals. The development of this trypanosome cell in heterologous mice is viewed as mediated principally thru nutritional factors supplied by rat serum with alteration of host-immune status being of lesser importance. |