Comparison of sensitization antigens of the brown-banded cockroach (Supella longipalpa) and German cockroach (Blattella germanica) in the animal model

Cockroaches are one of the most important causes of asthma and allergies in residential areas. Sensitization to cockroach allergens is an established risk factor for asthma among populations. In this study, cockroach bodies and feces from the two species were separately dried, homogenized, and centrifuged after one day in phosphate-buffered saline (PBS). The protein concentration of the samples was then determined using the Bradford method. The supernatant was prepared for injection into 20 mice, and after four weeks of subcutaneous injection, an ELISA test was used to determine the antibody titer against the injected antigen. After the overdoes (OD) samples were detected, an SDS-PAGE test was performed to determine the peptides' molecular band and molecular weight. Lastly, a Western blot test with anti-mouse IgE conjugated HRP (Horseradish Peroxidase) for IgE in mouse serum was prepared.  A comparison of the cockroach OD with the rest showed that more antibodies, both for feces and for the body, were produced in the mouse serum than in other cockroaches. A Western blot test also showed that the body of this cockroach produced IgE antibodies in the serum of mice. The molecular weights of body and feces samples of German cockroaches by SDS-PAGE were 85, 75, and 100 kDa, respectively, and 75, 35, 60, and 60 kDa, respectively, for the body and feces of the brown-banded cockroach. The weight of IgE protein bands (antibody) produced in mouse serum by western blot varied from 60 to 220 kDa. The upper titer of the whole body and the cockroach feces of Supella longipalpa were observed in comparison with the other cockroaches, as well as the IgE antibody band of the Supella whole body was observed, which indicated the risk of allergy to this cockroach.