In some tropical areas the mite Blomia tropicalis is a clinically important allergenic component of house dust, inducing specific IgE immune response in patients with allergic respiratory diseases such as asthma and rhinitis. The identification of allergens of this mite is necessary to obtain appropriate reagents for diagnostic and treatment procedures. We carried out this study using immunoblotting to detect the allergens of B. tropicalis. Our results demonstrate that this mite has one major allergen (11-13 kDa) and three other important allergens with about 50% binding (64, 36 and 33 kDa). Therefore, B. tropicalis should be regarded as an important source of allergens in the house dust in tropical areas, besides those derived from other mites.

Background: In tropical climates, sensitization to Bloma tropicalis and Dermatophagoides pteronyssinus is high and mainly directed to species–specific allergens. There is some cross–reactivity between extracts of these mites, probably due to the group 5 allergens that have high sequence homology. Objective and Methods: We used the radioallergosorbent test (RAST), RAST inhibition and immunoblotting inhibition experiments to investigate the cross–reactivity between the recombinant allergens BtM and Der p 5, expressed as glutathione S–transferase fusion proteins, to detect the epitopes involved and to analyze the importance of this cross–reactivity. Results: Seventy–nine percent of 48 patients sera were RAST positive to both recombinants, with a strong correlation (r = 0.8, p<0.0001). BtM inhibited 25 and 21.1% of IgE–binding to B. tropicalis and D. pteronyssinus extracts respectively and Der p 5 inhibited 22 and 24% of IgE–binding to D. pteronyssinus and B. tropicalis extracts. Furthermore, BtM inhibited 74.5% of IgE binding to Der p 5 and Der p 5 inhibited 72.4% of IgE–binding to BtM. RAST inhibition with BtM–derived synthetic peptides showed that peptide 4 (residues 35–50) and peptide 5 (residues 46–61) inhibited 37 and 16% of IgE–binding to BtM while peptides 5 and 2 (residues 14–30) were able to inhibit the IgE binding (32 and 28%, respectively) to Der p 5. Conclusion: There is cross–reactivity between BtM and Der p 5, which explains almost all the cross–reactivity between the two mite extracts. This cross–reactivity seems to be related to epitope(s) at the C–terminal segment of these allergens.

The study reports a prevalence of (4%) when performing the specific IgE to latex and (24%) to the cutaneous test with antigen to total latex. This data allows us to continue evaluating the personnel at risk at the hospital, with better results in the administration of Labor Medicine at this medical institution.

No abstract

ResumenEn la actualidad, los trastornos respiratorios están entre los problemas de salud más frecuentes y, entre ellos, el asma aparece como una entidad muy común en niños y adultos. El asma alérgica es una enfermedad multifactorial. El componente ambiental es de gran importancia, lo cual ha sido ampliamente documentado gracias a los avances científicos que en los últimos años se han dado en el campo de la alergología experimental. Los ácaros domésticos son la principal fuente de alergenos en el polvo casero; dichos alergenos son considerados, hoy en día, como los principales inductores de las manifestaciones alérgicas respiratorias. Estos animales son artrópodos de distribución mundial, siendo Dermatophagoides pteronyssinus y Blomia tropicalis los que más frecuentemente se encuentran en el ambiente doméstico. Las mencionadas especies ejercen un gran impacto clínico porque la mayoría de la población asmática y rinítica presenta altos niveles de IgE contra sus alergenos lo cual, sin duda, influye en la patogénesis de la inflamación crónica que caracteriza a esas enfermedades. La presente revisión describe la biología, epidemiología y aspectos moleculares de los alergenos de Dermatophagoides pteronyssinus y Blomia tropicalis, como una información muy útil para los médicos y demás integrantes del equipo de salud que tengan el interés y la oportunidad de efectuar un manejo integral de estos problemas. SummaryRespiratory diseases are very frequent health problems today, some of them, such as asthma, affect a great percentage of both both adults and children. Allergic asthma is a multifactorial disease, the environmental component being crucial, afact which has been widely documented as a result of recent scientific advances in experimental allergology. Domestic mites are the main allergen source in household dust. Such allergens are now considered to be important inducers of respiratory allergic symptoms. These animals are arthropoda with a worlwide distribution, being Dermatophagoidespteronyssinusand Blomia tropicalis, the commonest found in the domestic environment.These species are clinically relevant because the rnajority of asthmatic and rhinitic patients present high titers of IgE antibodies against mite allergens which strongly influence the pathogenesis of the inflarnmation which characterizes these diseases. This review describes the biology, epidemiology and molecular aspects of Dermatophagoidespteronyssinusand Blomia tropicalis allergens, information that could be useful for physicians and health workers having the interest and opportunity to carry out integral management of these problems.Las enfermedades respiratorias son de las más ellas, como el asma, están inclusive aumentando frecuentes que padece el humano. Algunas de en mortalidad por múltiples razones, entre las cuales, la falta de conocimientos sobre aspectos Investigadores, instituto de Investigaciones Inmunológicas, C~ucialeS de su etiología Y Patogénesis Parece Universidad de Cartagena, Cartagena.ser la más im~ortante.