Human mast cell carboxypeptidase. Selective localization to MCTC cells

• Published in: The Journal of immunology (1950) Vol. 147; no. 1; pp. 247 - 253
• Main Authors: Irani, AM, Goldstein, SM, Wintroub, BU, Bradford, T, Schwartz, LB
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 01-07-1991; American Association of Immunologists
• Subjects: Analysis of the immune response. Humoral and cellular immunity; Antibodies, Monoclonal - immunology; Biological and medical sciences; Carboxypeptidases - immunology; Carboxypeptidases - metabolism; Chymases; Cross Reactions; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Immunobiology; Immunohistochemistry; Mast Cells - enzymology; Monocytes - enzymology; Monocytes - immunology; Neutrophils - enzymology; Neutrophils - immunology; Organs and cells involved in the immune response; Peptide Hydrolases - analysis; Serine Endopeptidases - analysis; Human; Immunohistochemistry; Enzyme; Immunocytochemistry; Carboxypeptidase; Mast cell; Skin
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.147.1.247

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.