Aspects and embodiments of the instant disclosure provide therapeutic methods and compositions comprising interleukin 12 (IL-12) as a hematopoietic immunotherapy (HIT) useful for treating or preventing a cancer patient from chemotherapy-induced cytopenias necessitating a dose reduction and/or dose delay. following exposure of the patient to chemotherapeutic agents, the method comprising: administering a dose of therapeutically effective amount of a pharmaceutical composition comprising substantially isolated IL-12 to the subject, whereby cytopenias are reduced and leading to increases responses to the chemotherapy agent(s).diminished.
