Characterization of a B cell surface antigen with homology to the S100 protein MRP8.
The S100 proteins comprise a large sub-family of the EF-hand calcium-binding proteins. Here we describe a novel monoclonal antibody recognizing a B cell surface antigen. This monoclonal antibody immunoprecipitates three proteins in the 12-18 kDa range and the smallest of these proteins has a striking homology at its amino-terminus to human MRP8, a myeloid specific member of the S100 family. Similarly to MRP8 in myeloid cells, this antigen is expressed in the cytoplasm of B cells and is secreted by LPS-induced activated B cells. This surface antigen is not B cell specific. Since MRP8 is not expressed by lymphoid cells, however, this antibody appears to recognize a new member of the S100 family.
Shapiro
M A
MA
Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, Maryland, 20892, USA. sharpirom@cber.fda.gov
Fitzsimmons
S P
SP
Clark
K J
KJ
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000737:chemistry* / Q000235:genetics; D000944:Antigens, Differentiation, B-Lymphocyte / Q000737:chemistry* / Q000235:genetics; D001402:B-Lymphocytes / Q000276:immunology*; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D040501:Calgranulin A; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009418:S100 Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D017386:Sequence Homology, Amino Acid
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000944:Antigens, Differentiation, B-Lymphocyte; D002135:Calcium-Binding Proteins; D040501:Calgranulin A; D009418:S100 Proteins