Cytokine proteins that stimulate growth and reproduction of certain kinds of blood cells in the bone marrow . Also referred to as growth factors . The production of white blood cells is controlled by colony stimulating factors. Cancer chemotherapy and inherited disorders are among the causes of low white blood counts, which lower resistance to infection. Thus, CSFs are being investigated not only as a way to counteract low white blood cell counts, but also as a way to produce specific types of white blood cells. In addition, there is hope that CSFs can stimulate the body to produce additional bone marrow as well as cause some cancer cells to stop dividing.