Effect of the house dust mite allergen Der p 1 on tryptase release from human mast cells

• Published in: Genetics and molecular research 2016-01, Vol.15 (2)
• Main Authors: Wang, D Q, Shen, Y Y, Xu, J H, Tang, H
• Format: Article
• Language: English
• Subjects: Antigens, Dermatophagoides - immunology; Antigens, Dermatophagoides - pharmacology; Arthropod Proteins - immunology; Arthropod Proteins - pharmacology; Calcium - metabolism; Cell Line; Cysteine Endopeptidases - immunology; Cysteine Endopeptidases - pharmacology; Dermatophagoides pteronyssinus; Flow Cytometry; Humans; Mast Cells - drug effects; Mast Cells - enzymology; Mast Cells - immunology; Oligopeptides - pharmacology; Receptor, PAR-2 - antagonists & inhibitors; Receptor, PAR-2 - biosynthesis; Receptor, PAR-2 - immunology; Signal Transduction; Tryptases - metabolism
• ISSN: 1676-5680; 1676-5680
• DOI: 10.4238/gmr.15028284

This study aimed to investigate the effects of the house dust mite allergen Der p 1 on the secretion of tryptase from the human mast cell line HMC-1. Flow cytometry was used to determine the expression levels of protease-activated receptor-2 (PAR2) on the surface of HMC-1 cells. HMC-1 cells were treated with Der p 1, SLIGRL-NH2 (PAR2 agonist), LRGILS-NH2 (control peptide for PAR2), or Der p 1 + FSLLRY (PAR2 antagonist), and the tryptase levels were measured using enzyme-linked immunosorbent assay. The biological functions of PAR2 were determined using the calcium green indicator, and intracellular calcium fluorescence intensity in the different groups (Der p 1, SLIGRL-NH2, LRGILS- NH2, Der p 1 + FSLLRY, tryptase, tryptase + FSLLRY, or cell culture medium) was detected by laser scanning confocal microscopy. The mast cells expressed PAR2 receptor on their surfaces. Der p 1 alone induced a significant release of intracellular calcium and tryptase in HMC-1 cells compared with the SLIGRL- NH2 treatment group and the control group. The combination of Der p 1 and FSLLRY partly inhibited intracellular calcium and tryptase release in HMC-1 cells compared with the Der p 1 treatment group. Moreover, tryptase induced a significant release of intracellular calcium in the HMC-1 cells. Der p 1 induced HMC-1 cell degranulation and the release of tryptase by activating the PAR2 receptor on the cell surfaces. Tryptase activated the PAR2 receptor and induced intracellular calcium release from the HMC-1 cells in a positive feedback loop.