title: Human mast cell carboxypeptidase. Selective localization to MCTC cells.
abstract: Two murine mAb were prepared against human mast cell carboxypeptidase (HMC-CP) purified from human skin, and were termed CP1 and CP2, respectively. Double immunohistochemical labeling of Carnoy's-fixed sections of human skin, lung, and gastrointestinal tissue with CP1 and CP2, respectively, and with a murine monoclonal antitryptase antibody demonstrated that HMC-CP was selectively present in a subset of human mast cells. Double labeling experiments with CP1 and CP2, respectively, and a murine anti-chymase mAb demonstrated the presence of HMC-CP in the tryptase-positive, chymase-positive mast cell type (MCTC) only. Immunohistochemical labeling of peripheral blood leukocytes resulted in staining of monocytes with CP2 but not with CP1. In addition to chymase and a cathepsin-G like proteinase, HMC-CP is another neutral protease that is selectively present in the MCTC tryptase-positive, chymase-positive mast cells type of mast cell, thus extending the biochemical definition of human mast cell heterogeneity.
authors.affiliation: Department of Pediatrics, Medical College of Virginia, Richmond 23298.
authors.forename: A M
authors.initials: AM
authors.lastname: Irani
authors.forename: S M
authors.initials: SM
authors.lastname: Goldstein
authors.forename: B U
authors.initials: BU
authors.lastname: Wintroub
authors.forename: T
authors.initials: T
authors.lastname: Bradford
authors.forename: L B
authors.initials: LB
authors.lastname: Schwartz
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D002268:Carboxypeptidases / Q000276:immunology* / Q000378:metabolism; D053818:Chymases; D003429:Cross Reactions; D006801:Humans; D007150:Immunohistochemistry; D008407:Mast Cells / Q000201:enzymology*; D009000:Monocytes / Q000201:enzymology / Q000276:immunology; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology; D010447:Peptide Hydrolases / Q000032:analysis; D012697:Serine Endopeptidases / Q000032:analysis
chemical_list: D000911:Antibodies, Monoclonal; D002268:Carboxypeptidases; D010447:Peptide Hydrolases; C023073:tosylarginine methyl ester hydrolase; D012697:Serine Endopeptidases; D053818:Chymases