CD4 and neoplasm: Splenocytes from tumor bearing mice were analyzed to assess the influence of these cytokine alterations, revealing no significant differences in the numbers of CD4+ and CD8+ T lymphocytes, B220+ B lymphocytes, and NK1.1+ cells, but increased development of CD11b+Ly6Ghi cells in Rip2-deficient compared to wild-type mice, that represent the granulocytic MDSC population (Fig 4B).