ABSTRACT
Objective:To investigate the modulatory effect of IL-29 on trypsin-induced protease activated receptors (PARs) ex-pression on P815 mast cell.Methods:After P815 mast cells were challenged with different concentrations of IL-29 alone or combined with trypsin for 2 h, 6 h and 16 h, the challenged cells were collected and analysed by flow cytometry to detect the protein expression of PARs on P815 cells, and analysed by real time RT-PCR to detect the mRNA expression of PARs on P 815 cells.Results:Compared with the corresponding control , IL-29 induced significantly decreased expression of PAR-1 at protein and mRNA level on P815 cells, and upregulated PAR-3, PAR-4 mRNA level on P815 cells, whereas IL-29 did little effect on the expressions of PAR-2,3,4 at protein level on P815 cells accordingly.Preincubation of mast cell with IL-29 did not alter trypsin-induced PAR-1 expression on P815 cells, whereas up-regulated expression of PAR-2, 3, 4 were detected when P815 cell were pre-treated with IL-29 before being challenged with trypsin compared with the corresponding control .Conclusion: IL-29 can upregulate trypsin-induced PARs expression on mast cells through which participated in mast cell related inflammation .
ABSTRACT
Among cockroaches (CR) that live in people’shomes, two species, i.e., German CR (Blattella germanica) and American CR (Periplaneta americana) predominate in temperate and tropical areas, respectively. CR is an important source of inhalant indoor allergens that sensitize atopic subjects to (localized) type I hypersensitivity or atopy including allergic rhinitis and atopic asthma. In Thailand the predominant CR species is P. americana. CR allergens are found throughout CR infested houses; the number found in kitchens correlates with the degree of CR infestation while sensitization and reactivation of the allergic morbidity are likely to occur in the living room and bedroom. Levels of the CR allergens in homes of CR allergic Thais, measured by using locally made quantification test kits, revealed that the highest levels occur in dust samples collected from the wooden houses of urban slums and in the cool and dry season. CR allergens are proteins that may be derived from any anatomical part of the insect at any developmental stage. The allergens may be also from CR secretions, excretions, body washes or frass. The proteins may be the insect structural proteins, enzymes or hormones. They may exist as dimers/multimers and/or in different isoforms. Exposure to CR allergens in infancy leads to allergic morbidity later in life. Clinical symptoms of CR allergy are usually more severe and prolonged than those caused by other indoor allergens. The mechanisms of acute and chronic airway inflammation and airway hyper-responsiveness (AHR) have been addressed including specific IgE- and non-IgEmediated mechanisms, i.e., role of proteaseactivated receptor-2 (PAR2). Participation of various allergen activated-CD4+ T cells of different sublineages, i.e., Th2, Th17, Th22, Th9, Th25, Tregs/Th3 as well as invariant NKT cells, in asthma pathogenesis have been mentioned. The diagnosis of CR allergy and the allergy intervention by CR population control are also discussed.
ABSTRACT
Objective To investigate the expression of protease activated receptors(PARs)in mast cells.Methods Reverse transcription polymerase chain reaction(RT-PCR),flowcytometry and immunofluorescent cell staining were used to detect the expression of PARs in mast cell lines P815 and MC/9 at the levels of protein and mRNA.Results Both the P815 and MC/9 of mast cell lines expressed PAR-1,PAR-2,PAR-3 and PAR-4 at either protein or mRNA level.Conclusion The expression of all the four PARs in mast cells were detectable,which may be of significance for the further study on the function of PARs in mast cells.