TNF can act as a direct cytotoxin to tumor cells, also it can induce fever, sleep, stimulate production of other cytokines, activate macrophages and mediate inflmaamtion. CSF can promote the growth of other wbc's. Clinically An elevated total white blood cell count is called leukocytosis, a decreased total wbc count is called leukopenia. Leukocytosis occurs during pregnancy, emotional stress, strenuous exercise, in response to all types of infections, collagen disorders, leukemias, transfusion reactions, parasitic infestations and inflammatory disorders. Any bacterial infection is likely to cause an increase in segmented neutrophils.
Viral infections are more likely to cause an increase in monocytes and lymphocytes.
The Biologic Basis for Disease in Adults and Children.