Cytological Identification of Proliferating Donor Cells in Chick Embryos injected with Adult Chicken Blood

Abstract

THE enlargement of the embryonic chick spleen which accompanies chorio-allantoic grafting of adult chicken spleen was first described by Murphy¹ in 1916. This phenomenon attracted the attention of a number of workers who believed that the splenomegaly was brought about by a proliferation of embryonic cells in response to some stimulus provided by the implanted spleen^2,3. Simonsen⁴ in 1957 showed that the splenic enlargement also occurred following the intravenous injection into the embryo of adult chicken blood or spleen cells. He showed that most embryos injected with homologous adult blood died of hæmolytic anæmia and the results of Coombs' tests strongly suggested that antibodies against the host red blood cells were present. He came to the conclusion from the results of his experiments that proliferating donor cells were responsible for the antibody production and the splenic enlargement.