NOVEL SPECIFIC CHEMOTACTIC RECEPTOR FOR S100L PROTEIN ON GUINEA-PIG EOSINOPHILS

We isolated a new chemotactic protein from bovine lung, and its partia l protein sequence analysis indicated that this protein was identical with S100L, one member of the Ca2+-binding S100 protein family. The ch emotactic activity of S100L on guinea pig eosinophils is observed at 0 .1nM protein concentration, and the effects appear mediated by a novel specific surface receptor. We characterized the receptor for S100L on guinea pig eosinophils. Scatchard analyses of the data that [I-125]S1 00L bound to S100L receptor indicate the presence of two receptor popu lations on eosinophils with a Kd value of 3.3 x 10(-11)M and 1.1 x 10( -9)M. Thus, S100L protein has the most potent chemotactic activity on guinea pig eosinophils of all the chemotactic proteins. (C) 1996 Acade mic Press, Inc.