MONOCYTE COMPLEMENT STIMULATOR - LYMPHOCYTE-T PRODUCT WHICH STIMULATES SYNTHESIS OF THE 2ND COMPLEMENT COMPONENT (C2)

Monocyte complement stimulator (MCS), a lymphokine previously shown to increase the rate of synthesis of the second complement component (C2) by human monocytes, is produced by sensitive T lymphocytes when exposed to antigen. MCS production requires cooperation of T lymphocytes with monocytes during the first 24 hr of exposure to antigen; both cell types must be capable of synthesizing protein during this time. MCS was found to differ from MIF in two ways: First, antigen-stimulated B lymphocytes and monocytes produce MIF but not MCS and second, MCS is destroyed by heating to 56 °C for 30 min while MIF retains its activity. © 1979.