Abstract: The invention provides methods for treating pathological conditions associated with an undesirable inflammatory component. The invention is generally directed to reducing inflammation by administering cells that modulate microglia activation. The invention is also directed to drug discovery methods to screen for agents that modulate the ability of the cells to modulate microglia activation. The invention is also directed to cell banks that can be used to provide cells for administration to a subject, the banks comprising cells having desired levels of potency to modulate microglia activation.