No abstract

Background The house dust mites (HDM) constitute a major cause of allergic diseases all over the world. Genes encoding interleukins 12B and 17A which determine the course of T cell-mediated immune response are prime candidates as allergic disease susceptibility. The purpose of this study was to evaluate whether a single-nucleotide polymorphisms (SNP) of interleukins 12B + 1188A/C (rs3212227) and 17A −197G/A (rs2275913) confers susceptibility to HDM allergic diseases. Through a case-control study, 120 subjects served as 60 dust mites' allergic patients and 60 healthy non-allergic controls. Total immunoglobulin (Ig) E level, eosinophilic count, serum interleukins 4, 10, 12B, and 17A levels for the studied subjects were measured. Then, genotyping of single-nucleotide polymorphisms (SNPs) at +1188A/C for IL12B and −197G/A for IL17A gene were conducted using restriction fragment length polymorphisms (RFLP-PCR). Results The present study showed that in HDMs' allergic subjects there was a significant increase in IL12B (+1188 A/C) and IL17A (−197 G/A) genotype variants compared to that of the controls. There was a significant increase in total IgE levels, eosinophil counts, and the levels of both IL-4 and IL-17A, while IL12B was significantly lower in patients compared to that of the controls. There was no significant difference in IL-10 levels between patients and controls.                                                                             Conclusion Our findings indicate that IL12B (+1188 A/C) and IL17A (−197G/A) might be associated with an increase in the susceptibility to dust mites’ allergic patients.

Background Domestic mites are a primary source of allergens indoors all over the world. Extracts of mite allergens are important for diagnosing and treating mites allergy. The effective cultivation processes play a critical role in the final composition of mites' allergen extracts. In order to produce large amounts of antigens of domestic mites, culture techniques of domestic mites were studied. Domestic mites were isolated from collected dust samples and cultured on a fine-ground mixture of dust and sawdust (2:1). While dry yeast, wheat germ, and cornflour were used at a ratio of 2:1:1 for nutrition. Food was placed over a few centimeters of cement base that had been placed on the bottom of the rearing containers. The population growth rates were determined. Results Successful methods for mite cultures utilize high protein and carbohydrate foods, an average temperature of (25 ± 2) °C and relative humidity (80 ± 5) %. During a 14-week observation period of mites' culture, the peak in number was obtained after 8 weeks of the culture in Tyrophagus, 10 weeks in Dermatophagoides, and 12 weeks in Blomia; thereafter, the number decreased. Significant differences were found in the growth rates of Dermatophagoides (P = 0.02) and Blomia (P = 0.03) in between pure and mixed cultures. Conclusions The modifications made to the mixture of diet used for cultivation showed a high yield of domestic mites. Also, the cement layer also is an excellent way to make space for egg laying and prevent mites from escaping.

No abstract