IDENTIFICATION OF A NEW ENDOGENOUS PLATELET-ACTIVATING FACTOR-LIKE MOLECULE IN GINGIVAL CREVICULAR FLUID

Periodontal disease is an inflammatory disease and the major cause of tooth loss in adults. Bacteria and their products are the causative ag ents of this disease. Endogenous molecules mediate the inflammatory pr ocess and play a major role in its amplification and perpetuation as w ell as in the ensuing tissue destruction, The relationship between pla telet-activating factor (PAF) and periodontal disease has not so far b een examined thoroughly. We have isolated a phospholipid molecule with PAF-like activity from gingival crevicular fluid. This molecule, puri fied on HPLC, causes washed platelet aggregation with EC50 value 0.1 m u M, based on phosphorus determination. It acts through PAF-receptors and is inactivated by PAF-acetylhydrolase. In addition, this phospholi pid presents biological activity towards human platelets. The combinat ion of the results obtained from the chemical and enzymic treatments, the biological assays as well as results from the electrospray analysi s, leads to the conclusion that this phospholipid is a hydroxyl-PAF an alogue with relative molecular mass 703. This PAF-like molecule may be implicated in periodontal disease.