The spleen stores and purifies erythrocytes, metabolizes hemoglobin, and recycles iron. The spleen also provides a critical function for the immune system by mounting a primary immune response to antigens in the blood and synthesizing antibodies. Splenocytes are mononuclear cells derived from the spleen and include T-lymphocytes, B-lymphocytes, NK-cells, and NK Tcells. Primary rat splenocytes (RS) can be used to isolate CD4+ T-cells, CD8+ T-cells, and CD45R+ B cells. RS from ScienCell Research Laboratories are isolated from normal adult rat spleen. RS are depleted of splenic macrophages, cryopreserved directly after isolation, and delivered frozen. Each vial contains at least 10 million cells in 1 ml volume. RS are quality control tested for viability. RS are negative for mycoplasma, bacteria, yeast, and fungi. RS can be maintained for a limited period of time in culture using the conditions provided by ScienCell Research Laboratories and are not intended for long-term culture. Recommended Medium It is recommended to use HematoGro Medium (HemGM, Cat. #5501) for short-term maintenance of RS in vitro.