However, after treatment with anti-CD8, the level of CD45+ TIL fell in both control and EMT6siCD200 tumors relative to untreated mice, in parallel with the increase in tumor size of EMT6siCD200, again consistent with the notion that CD8+ T cells play an important role in anti-tumor immunity-note there was no significant change in size of control EMT6 tumors after anti-CD8 treatment, despite the fall in CD45+ TIL. The gene discussed is PTPRC; the disease is neoplasm.