CD4 and neoplasm: Similar to the results obtained with TRAMP-PRKN–KO mice, PRKN immune modulation in the AT3 model was restricted to the tumor microenvironment, as splenocytes harvested from control or Doxy-treated animals showed no significant differences in the expression of CD8+ (Supplemental Figure 8E) or CD4+(Supplemental Figure 8F) T cell markers.