Working the bugs out of asthma

December 12th, 2017

Cockroach antigens (proteins found in the insects' feces, saliva, eggs, and shed cuticles) have been implicated as one of the leading causes of asthma among inner-city children. These antigens can trigger severe allergic reactions, and even tiny amounts can be potentially fatal to sensitive asthmatics. Cockroach allergies are particularly difficult to treat because the cockroach antigens are so persistent. The challenge lies in pinpointing the precise location of the antigens within a house so that they may be removed. If untouched, antigens may persist in a house, perhaps in one dusty corner of a room, for years. So even if the insects themselves are exterminated, the actual source of the allergy remains. Knowing this, researchers at the United States Department ofAgriculture'sAgricultural Research Service, theArkansas Children's Hospital Research Institute in Little Rock,Arkansas, and the FDA have set out to develop a home test kit that homeowners can use to detect cockroach antigens. The researchers first studied cockroaches' distribution patterns in a specially constructed containment building using an engineering technique called spatial analysis. Once the spatial distribution patterns of the test cockroaches–and, therefore, their antigens–were determined, the researchers analyzed the antigens using polyclonal antibodies to cockroach antigens. Next, the researchers cleaned the facility with a common household cleaner. Spatial analysis showed that cleaning removed 90% of the cockroach antigens and highlighted where the rest remained. The next step is to refine the laboratory-scale assay into a simple, home-based test kit. The kit will probably include probes to check many sites in a home before and after cleaning with household cleansers. The test kit could also be adapted by the pest control industry to assess, target, clean, resample, and verify that all cockroach antigens are eliminated. The technology is also helping to develop and test new cockroach repellents that are environmentally friendly.