Research Article

Development of a glutaraldehyde-polymerized Blomia tropicalis extract (allergoid) for Allergen Immunotherapy

Abstract

A curative treatment for hypersensitivity to Blomia tropicalis is yet far from being ideally achieved; however, desensitization strategies conducted with unmodified natural extracts and chemically modified allergens (allergoids) are promising therapeutics. This study aims to evaluate and compare methodologies to culture HDM, extract their proteins, and produce allergoids by glutaraldehyde polymerization. We compared the growth of Blomia tropicalis in two different culture media. Medium A was prepared with yeast extract and rodent ration. Medium B was prepared with yeast extract and Tetramin®. We compared the extraction of the proteins performed with two different buffers: Phosphate Buffered Saline (PBS) and Borate Buffer (BBS). After extraction, the distribution of proteins was demonstrated by SDS-PAGE, and the native extract was compared with its glutaraldehyde-polymerized allergoid. Both cultures were inoculated with approximately 2,000 mites/g of culture. The population peak was reached after 105 days in medium A (52,000 mites/gram of culture) and 90 days in medium B (71,000 mites/gram). Therefore, faster population growth and a higher population density are observed in medium B. SDS-PAGE showed that the allergens’ low molecular bands disappeared after polymerization, obtaining polymers with a molecular weight greater than 150 kDa. For B. tropicalis, the yeast extract enriched with Tetramin® as a culture medium presented better results for growing; however, both media and extraction buffers enabled the production of a native protein extract and, from this, the production of a polymerized allergoid.