Analysis of properties and proinflammatory functions of cockroach allergens Per a 1.01s

Cockroaches have been identified as one of the major indoor allergens inducing perennial rhinitis and asthma. Per a 1s are a group of the major allergens from American cockroach. Although Per a 1s are major allergens from American cockroach, factors contributing to the allergenicity of Per a 1s are still poorly defined. To investigate the effects of Per a 1s on the expression of PARs and the release of proinflammatory cytokines from mast cells. Per a 1.0101 and Per a 1.0104 were cloned from American cockroach and then expressed in Eschericia coli. The purified allergens were used to stimulate P815 mast cells, and the expression of protease-activated receptors (PARs) was determined by real-time RT-PCR and flow cytometry. The levels of IL-4 and IL-13 in culture media were detected with ELISA. Sera from 80 and 77.3% of cockroach allergy patients reacted to recombinant Per a (rPer a) 1.0101 and rPer a 1.0104, confirming they are major allergens. Both rPer a 1.0101 and rPer a 1.0104 had no enzymatic activity, but rPer a 1.0101 upregulated the expression of PAR-1 and PAR-2, and rPer a 1.0104 enhanced the expression of PAR-1 and PAR-4 proteins. Both recombinant allergens were able to increase the release of IL-4 and IL-13 from P815 mast cells. This is the first study aiming to investigate functions of group 1 allergens of American cockroach. rPer a 1.0101 and rPer a 1.0104 have the capacity to upregulate the expression of PARs and to enhance Th2 cytokine production in mast cells.