Graft-versus-host reaction in F 1 recipients in the absence of donor (parental) cell proliferation.

Abstract

AbstractThis study concerns the role of donor cell proliferation in graft‐versus‐host (GVH) reaction, using in vivo and in vitro systems. We have confirmed the reports of others that treatment of parental cells with mitotic inhibitors prevents the development of GVH splenomegaly in newborn F1 recipients. However, in an in vitro GVH assay, parental cells treated with mitomycin C at doses as high as 50 μg/ml were shown to cause enlargement of newborn F1 spleen fragments. This apparent anomaly was partly resolved by showing that mitomycin C‐treated parental cells could give rise to splenomegaly in newborn F1 mice in vivo, provided they were mixed with newborn F1 spleen cells prior to injection. The possibility that mitotic inhibitors adversely affect the ability of parental cells to migrate to the sites of interaction with recipient cells, rather than inhibiting their actual ability to interact (and hence cause proliferation) is discussed. The nature of this GVH interaction is also considered.