The Influence of Environmental Temperature and Humidity on Temporal Decomposition of Cockroach Allergens Bla g 1 and Bla g 2 in Feces

Abstract

The aim of the study was to establish a model of the environmental fate of German cockroach (Blattella germanica L.) allergens Bla g 1 and Bla g 2 in feces under controlled and field conditions. Temporal decline (3, 6, and 9 mo) of allergens Bla g 1 and Bla g 2 in the feces protected from cleaning was measured under laboratory and experimental household conditions. The influence of environmental temperature (15, 20, 25, 30, and 35 degrees C) and moisture (53, 75, 85, and 100% RH) on allergen degradation was estimated for 3, 6, and 9 mo. Bla g 1 was more stable than Bla g 2 and the proteins. The proteins and Bla g 2 contents were correlated negatively with the decomposition time; Bla g 1 was not. However, when the content of Bla g 1 in control and exposed tubes was compared, the decrease after exposure was significant at exposure in 35 degrees C, 53 and 100% RH. In laboratory, the shortest half-life (16-38 d) of Bla g 2 was at high temperature and humidity (100% RH at 35 degrees C), whereas the longest half-life (340 d) was at 25 degrees C and 85% RH. In the apartment, the half-life was 406 d. The results indicate that Bla g 1 and Bla g 2 allergens can persist in feces for several months under usual household humidity and temperature.

An atopic dermatitis-like murine model by skin-brushed cockroach Per a 2 and oral tolerance induction by Lactococcus lactis-derived Per a 2

“…Allergen avoidance is the best method, theoretically, for preventing allergic disease and manifestation. However, Per a 2 and Bla g 2, the major group 2 German cockroach allergens, could exist for more than a year in the household environment [ 20 , 44 ]. It might be difficult for allergic patients to avoid these long-term cockroach allergens.…”

IgE-Binding Epitope Mapping and Tissue Localization of the Major American Cockroach Allergen Per a 2

“…It has been reported that Bla g 2, the major Group 2 German cockroach allergen, 37 can exist in an apartment with a half-life of 406 days at proper temperature and humidity. 38 Whether Per a 2 is as robust in the environment as Bla g 2 requires more studies.…”

Storage of Cereals in Warehouses with or without Pesticides

“…The most important direct effect is associated with the contamination of www.videleaf.com food by arthropod fragments, which can be carcinogenic or allergenic. Stored-product pests, mites, and insects produce a variety of chemical compounds that cause allergic reactions in humans and domestic pets [15,16]. Indirectly, stored pests change the moisture content and temperature of stored food, developing optimal conditions for the growth of pathogenic microorganisms [17], or they host and transmit microorganisms, including antibiotic-resistant strains [18,19].…”