The CD4 cell dependency of SJL/J B-cell lymphomas as a target for cyclophosphamide therapy.

SJL/J B-cell lymphomas induce proliferation of syngeneic CD4 cells, on which the tumors are dependent for growth. We sought to determine whether cyclophosphamide (CY) treatment of tumor-bearing mice would be successful through effects on tumor cells, CD4 cells, or both. The markedly increased survival of treated mice derived predominantly from reduced proliferation of CD4 cells in response to tumor.