colony forming unit-spleen cells
a subpopulation of multipotential hemopoietic stem cells located in the bone marrow that is responsible for the formation of the myeloid elements of blood (e.g., erythrocytes, granulocytes, monocytes, and platelets); they resemble lymphocytes and are considered to belong to the null cell population. They have the capability of self-renewal.
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Examples: glitazone, GI cocktail, etc.