Adoptive transfer of immunity to Plasmodium berghei after busulfan and cyclophosphamide treatment of recipient mice.

Balb/c mice injected with P. berghei die about 21 days after infection. Successful cell transfer in mice was made possible by the pretreatment of the recipient with a combination of busulfan and cyclophosphamide. Cell counts showed that drug-treated mice contain 20 times less bone marrow cells than normal mice, and when injected with P. berghei die significantly later than normal controls. The animals were injected with normal (NBM) and immune bone marrow and normal (NSp) and immune spleen (ISp). The results obtained showed that ISp lengthens significantly the average survival time, producing cure of 50% of the recipients. Transfer of NSp and NBM also lengthens the average survival time.