PERIPHERAL-BLOOD LEUKOCYTES FROM MULTIPLE-SCLEROSIS PATIENTS ARE COATED WITH FACTORS INHIBITING THEIR CHEMOTAXIS IN THE PRESENCE OF MYELIN BASIC-PROTEIN

In this study myelin basic protein (MBP) was tested for its effect on chemotaxis of human peripheral blood leukocytes (PBL) and neutrophils from multiple sclerosis (MS) patients. MBP appeared to inhibit specifi cally the formyl-methionyl-leucyl-phenylalanine (FMLP)-induced chemota xis of both the total leukocyte population and neutrophils. In compari son, no inhibition of chemotaxis was observed in healthy donors and pa tients with other neurological diseases. From MS patients we collected neutrophil supernatants obtained by incubation of the cells in a seru m-free medium at 37-degrees-C for 60 min and evaluated their effect on chemotaxis of neutrophils from healthy donors. Chemotaxis of healthy donor neutrophils was inhibited specifically in the presence of MBP af ter treatment with these supernatants, presumably relating to the pres ence of immune complexes on the surface of neutrophils from MS patient s. Those complexes can be eluted into the incubation medium and coat h ealthy donor neutrophils, thus arming them specifically.