Induction of IgE Antibody Responses by GlutathioneS-Transferase from the German Cockroach (Blattella germanica)

Abstract

We report that a major 23-kDa allergen from German cockroach (Blattella germanica) is a glutathione S-transferase (EC 2.5.1.18; GST). Natural B. germanica GST, purified from cockroach body extracts by glutathione affinity chromatography, and recombinant protein expressed in Escherichia coli using the pET21a vector, showed excellent IgE antibody binding activity. B. germanica GST caused positive immediate skin tests in cockroach-allergic patients using as little as 3 pg of recombinant protein. The NH 2 -terminal sequence of the natural protein and the deduced amino acid sequence from cDNA were identical except for one substitution (Phe 9 3 Cys). Assignment of this protein to the GST superfamily was based on binding to glutathione and sequence identity (42-51%) to the GST-2 subfamily from insects, including Anopheles gambiae and Drosophila melanogaster. B. germanica GST contained 18 of the 26 invariable residues identified in mammalian GST by xray crystallography and exhibited enzymic activity against a GST substrate. Our results show that cockroach GST causes IgE antibody responses and is associated with asthma. The data strongly support the view that the immune response to GST plays an important role in allergic diseases.Cockroaches produce potent allergens, which give rise to IgE antibody (Ab) 1 responses in genetically predisposed individuals living in cockroach-infested housing (1-8). IgE Ab to cockroach are strongly associated with asthma, and sensitization to cockroach allergens is a major risk factor for hospital emergency room visits for asthma (5,9,10). Although cockroach may carry viral and bacterial pathogens, asthma is the only disease for which an unequivocal causal relationship with cockroach exposure has been established (9 -11). Over the last few years, several allergens from the principal domiciliary cockroach species, Blattella germanica (German cockroach) and Periplaneta americana (American cockroach), have been cloned and insights into their biological function have been obtained (12-15). B. germanica allergen Bla g 2 shows sequence homology to aspartic proteases, whereas Bla g 4 is a ligand-binding protein or calycin (12, 13). In Taiwan, P. americana is an important cause of asthma, and a 72-kDa allergen, Per a 3, has recently been cloned, which shows homology to insect hemolymph proteins (arylphorins) (14).We have identified an important B. germanica allergen with sequence homology to the glutathione S-transferase (GST) superfamily. These enzymes are involved in the detoxification of endogenous and xenobiotic toxic compounds and are widely distributed in most forms of life (16 -18). In molecular biology, plasmid vectors have been constructed to express foreign proteins in Escherichia coli, as fusion proteins with the COOH terminus of GST from Schistosoma japonicum. These high level expression systems (pGEX vectors) have been widely used for purification of recombinant proteins by glutathione affinity chromatography (19).Here, we report the sequence, purification, and recombinant expression...

There are more asthmatics in homes with high cockroach infestation

“…The present study showed that when there was cockroach home infestation (more than 5 dead insects after pesticide), there was also a 3.45 higher frequency of asthma in the children than when there was no cockroach infestation, in agreement with data of studies which used different techniques for the assessment of exposure (5,13).…”

“…Although the combination of cockroach allergy and exposure to high levels of infestation can explain some aspects of asthma among these patients, a clear causal relationship between these factors has not been sufficiently demonstrated (13,14) and more information should be obtained about this relationship.…”

Molecular cloning and epitope analysis of the peanut allergen Ara h 3

“…In recent years, a number of allergens have been identified that stimulate IgE production and cause IgEmediated disease (6)(7)(8)(9). Although considerable information exists on the identification, purification, and cloning of inhaled allergens (pollens, dust mites, animal danders, insects, and fungi), few food allergens have been identified and studied.…”

Glutathione S-transferases from the larval gut of the silkworm Bombyx mori: cDNA cloning, gene structure, expression and distribution

“…An increase in the activity of these enzymes is associated with resistance to all of the major classes of insecticides (Fournier et al, 1992;Prapanthadara et al, 1993;Huang et al, 1998;Ranson et al, 2001;Vontas et al, 2001;Ortelli et al, 2003;Enayati et al, 2005;Lumjuan et al, 2005). Due to the important role of GST, GST genes have been cloned from several insect species (Snyder et al, 1995;Arruda et al, 1997;Ranson et al, 1997;Ding et al, 2003;Valles et al, 2003;Claudianos et al, 2006;Yamamoto et al, 2005Yamamoto et al, , 2006Yamamoto et al, , 2007.…”