[Factors limiting in utero lymphocyte transplantation and cell therapy]

To evaluate factors of cell transplantation in utero in human, we have injected into rat fetuses of varied stage (n=61) several doses of non labeling lymphocytes mixed with FITC labeled latex beads. The ratio of fetal death and the histopathological effect longer after birth were assessed. Our results showed that the elevated fetal death ratio were observed after the injections of a high doses in young fetuses. Low doses provoked the same effect when injected to old fetuses. In living fetuses, histopathological lesions mimicking a graft versus host reaction were noticed throughout several organes six week after birth. We concluded that lymphocyte transplantation in utero depends on the dose of injected cells and stage of fetal development.