PHARMACOLOGICAL ACTIVITY OF CHEMICALLY-MODIFIED SUBFRAGMENT FROM HUMAN SERUM IGG .14. INHIBITORY EFFECT OF CARBOXAMIDE-METHYLATED LIGHT-CHAIN (G(1)L) ON TYROSINE PHOSPHORYLATION AND TUMOR-NECROSIS-FACTOR-ALPHA PRODUCTION FROM MURINE MACROPHAGES STIMULATED BY LIPOPOLYSACCHARIDE

Carboxamide-methylated light chain (G(1)L) from human serum IgG inhibited the secretion of tumor necrosis factor (TNF-alpha), one of the inflammatory cytokines, from adherent splenocytes and thioglycolate-induced peritoneal macrophages. The inhibition of TNF-alpha secretion by G(1)L was associated with disappearance of tyrosine phosphorylation on about 40kDa protein when thioglycolate-induced peritoneal macrophages were stimulated with lipopolysaccharide (LPS). It is possible that this G(1)L anti-inflammatory activity occurs through the blockage of the phosphorylation of about 40 kDa protein.