Identification of SLPI (Secretory Leukocyte Protease Inhibitor) in Human Mast Cells Using Immunohistochemistry and In Situ Hybridisation

• Published in: Biological chemistry Vol. 380; no. 4; pp. 489 - 493
• Main Authors: Westin, U., Polling, å., Ljungkrantz, I., Ohlsson, K.
• Format: Journal Article
• Language: English
• Published: Germany Walter de Gruyter 01.04.1999
• Subjects: Chymase; Humans; Immunohistochemistry; In Situ Hybridization; Mast cell; Mast Cells - metabolism; Nasal Mucosa - cytology; Nasal Mucosa - metabolism; Palatine Tonsil - cytology; Palatine Tonsil - metabolism; Protease inhibitor; Proteinase Inhibitory Proteins, Secretory; Proteins - metabolism; Salivary Proteins and Peptides - metabolism; Secretory Leukocyte Peptidase Inhibitor; SLPI; Tryptase
• ISSN: 1431-6730
• DOI: 10.1515/BC.1999.063

Recently interest has been focused on secretory leucocyte protease inhibitor (SLPI) and its role in immediate hypersensitive reactions, possibly by inhibiting mast cell chymase. The purpose of this investigation was to show whether or not SLPI is produced in mast cells. Double-immunolabelling revealed that SLPI coexists with mast cell tryptase (60%) and chymase (37%). On the other hand, in situ hybridisation studies demonstrated the expression of SLPI mRNA in all mast cells. The differences in results can be attributed to the fact that in situ hybridisation is a more sensitive method than immunohistochemistry. Hence, we conclude that SLPI is produced in human tonsillar mast cells.