[Porta-biliary area modifications during the graft-versus-host reaction in chick embryo and rat fetus].

Our results (light and electron microscopic study) show that both in chick embryos engrafted with fowl homologous spleen cells and in rat fetuses receiving blood cells from their own mother (homologous system) histologic changes occur in porta-biliary areas consisting in paravascular infiltrates (P.V.I.), bile ducts disorganization and periportal hepatocyte alterations. These modifications are closely similar to those described in other post-natal Graft Versus Host Reaction models. Yet, in both cases, the cells of the P.V.I. are chiefly of the granulocytic serie instead of the classical lymphoïd P.V.I.