A comparative study of the GVH-R in the chick embryo: effects of various allogeneic cells and various administration routes.

Allogeneic cells inoculated into immunologically immature chick embryos induce a Graft-Versus-Host Reaction (GVH-R), one of the manifestations of which is splenic enlargement. Splenomegaly varies with the composition of allogeneic cell suspensions, route of inoculation and age of recipient embryos at inoculation and autopsy. We have compared the splenomegaly induced by lymphoid cells from spleen or bursa of Fabricius with that induced by peripheral blood lymphocytes, after these cell preparations were either grafted on the chorioallantoic membrane (CAM) at 9 or 13 days or injected intravenously at 13 days. We confirm our previous findings that bursa cells grafted on the 9-day CAM induced splenomegaly as efficiently as other cell preparations. On the other hand, bursa cells did not mediate such an effect after they were injected at 13 days. On the whole, a hierarchy of decreasing efficiency is observed from PBL to spleen and finally to bursal cells. It appears that, as the recipient embryo ages, this hierarchy becomes more marked.