Differential Graft Resistance of C3H Mice Prztreated with Antitumor Drugs Against Balb/C Bone Marrow or Lymphoma Cells

Abstract

Sequential treatment of mice with 5–(3, 3′-dimethyl-l-triazeno)-imidazole-4-carboxamide (DTIC) and Cyclophosphamide (Cy) produced long-term inhibition of endogenous cells proliferation in the spleen and impairment of classical allograft response, similar to that obtainable with lethal total body irradiation. The growth of BALB/c bone marrow or of virus-induced LSTRA leukemia of BALB/c origin, was studied comparatively in drug-treated or irradiated histocompatible (BALB/c × DBA/2)F₁ or allogeneic C3H/HeN hosts. No splenic resistance of E type against bone marrow cells was detected in C3H recipients, either irradiated or drug-treated, confirming previous studies on the Hh susceptibility of C3tI strain. In contrast, strong transplantation resistance was drtected in the spleen, liver and lung of the same hosts, irradiated or drug-treated, and challenged with LSTRA cells. It follows that Hh—susceptible mice are competent for mounting a localized radioresistant and drug-resistant response, directed against a virus-induced lymphoma.