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Introduction: The use of specific antibodies capable of detecting allergens of the group 1 of house dust mites represents a potential strategy to reduce exposure and clinical symptomatology associated with asthma and allergic rhinitis. Objective: To produce and purify chicken antibodies specific for the dust mites Dermatophagoides sp. and B. tropicalis using the IgY technology. Materials and methods: We designed and synthesized oligopeptides showing immunogenic epitopes of Der p1, Der f1, and Blo t1. These were used to produce IgY antibodies in Hy Line Brown chickens. IgY were extracted from egg yolk using thiophilic chromatography. The immunogenicity and specificity were assayed by indirect ELISA and Dot Blot. Results: We obtained high reactivity of IgY antibodies against epitopes of allergens present in whole body mites extracts of D. farinae, D. pteronyssinus, and B. tropicalis. The highest IgY levels were registered between days 32 and 40 after immunization. The antibodies showed high immunoreactivity and specificity towards D. farinae proteins with detection limits above 0.03 µg of mite proteins under the experimental conditions used. Purified IgY did not show significant reactivity when binding to Periplaneta americana extract. Conclusion: The IgY technology allowed the production of specific antibodies against house dust mites group 1 allergens using non-glycosylated synthetic peptides. To our knowledge, this is the first time that this immunochemicals are used in the detection of mites of medical relevance.

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Resumen Introducción. La obtención de anticuerpos específicos capaces de detectar alérgenos del grupo 1 de ácaros del polvo doméstico representa una estrategia potencial de salud pública para reducir la exposición y la sintomatología clínica asociada con el asma y la rinitis alérgica. Objetivo. Producir y purificar anticuerpos aviares antialérgenos específicos del grupo 1 de los ácaros Dermatophagoides sp.y Blomia tropicalis utilizando la tecnología IgY. Materiales y métodos. Se diseñaron y sintetizaron oligopéptidos que evidenciaran epítopes inmunogénicos de los alérgenos Der p1, Der f1 y Blo t1 empleados posteriormente para producir anticuerpos IgY policlonales en gallinas Hy Line Brown. Las IgY presentes en las yemas de los huevos se purificaron mediante cromatografía tiofílica. Su inmunorreactividad y especificidad se determinaron mediante un inmunoensayo ELISA indirecto y Dot Blot. Resultados. Se obtuvo una reactividad elevada de las IgY contra epítopes de alérgenos presentes en extractos de cuerpo entero de D. farinae, D. pteronyssinus y B. tropicalis. Los niveles más altos de IgY se produjeron entre los días 32 y 40 de inmunización. Los anticuerpos mostraron mayor inmunorreactividad y especificidad en el reconocimiento de proteínas de D. farinae, con un límite de detección mayor de 0,03 µg de proteína total delcaroajo las condiciones experimentales analizadas. Las IgY purificadas no mostraron reactividad significativa frente al extracto de Periplaneta americana. Conclusión. La tecnología IgY permitió la producción de anticuerpos específicos contra alérgenos del grupo 1 de los ácaros del polvo al utilizar oligopéptidos sintéticos no glicosilados. Hasta donde se sabe, esta es la primera vez que se usan estos reactivos inmunológicos para la detección de ácaros de importancia médica.

Abstract Introduction: The use of specific antibodies capable of detecting allergens of the group 1 of house dust mites represents a potential strategy to reduce exposure and clinical symptomatology associated with asthma and allergic rhinitis. Objective: To produce and purify chicken antibodies specific for the dust mites Dermatophagoides sp. and B. tropicalis using the IgY technology. Materials and methods: We designed and synthesized oligopeptides showing immunogenic epitopes of Der p1, Der f1, and Blo t1. These were used to produce IgY antibodies in Hy Line Brown chickens. IgY were extracted from egg yolk using thiophilic chromatography. The immunogenicity and specificity were assayed by indirect ELISA and Dot Blot. Results: We obtained high reactivity of IgY antibodies against epitopes of allergens present in whole body mites extracts of D. farinae, D. pteronyssinus, and B. tropicalis. The highest IgY levels were registered between days 32 and 40 after immunization. The antibodies showed high immunoreactivity and specificity towards D. farinae proteins with detection limits above 0.03 µg of mite proteins under the experimental conditions used. Purified IgY did not show significant reactivity when binding to Periplaneta americana extract. Conclusion: The IgY technology allowed the production of specific antibodies against house dust mites group 1 allergens using non-glycosylated synthetic peptides. To our knowledge, this is the first time that this immunochemicals are used in the detection of mites of medical relevance.

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The production and characterization of an active recombinant N-acetylgalactosamine-6-sulfate sulfatase (GALNS) in Escherichia coli BL21(DE3) has been previously reported. In this study, the effect of the signal peptide (SP), inducer concentration, process scale, and operational mode (batch and semi-continuous) on GALNS production were evaluated. When native SP was presented, higher enzyme activity levels were observed in both soluble and inclusion bodies fractions, and its removal had a significant impact on enzyme activation. At shake scale, the optimal IPTG concentrations were 0.5 and 1.5 mM for the strains with and without SP, respectively, whereas at bench scale, the highest enzyme activities were observed with 1.5 mM IPTG for both strains. Noteworthy, enzyme activity in the culture media was only detected when SP was presented and the culture was carried out under semi-continuous mode. We showed for the first time that the mechanism that in prokaryotes recognizes the SP to mediate sulfatase activation can also recognize a eukaryotic SP, favoring the activation of the enzyme, and could also favor the secretion of the recombinant protein. These results offer significant information for scaling-up the production of human sulfatases in E. coli.

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Iduronate-2-sulfate sulfatase (IDS; EC 3.1.6.13) is an enzyme that belongs to human sulfatases. IDS deficiency causes the Hunter syndrome or mucopolysaccharidosis type II (MPS II; OMIM 309900). We have been developing an expression system for human recombinant IDS (hrIDS) in Pichia pastoris, therefore a method was required for its detection during production and purification processes, which could be used also to measure the enzyme in human fluids. In this study, an immunoquantification assay for human and recombinant IDS was developed with the combination of two antibodies. Rabbit IgG and chicken IgY were used as IDS capture and detection antibodies, respectively. Chicken IgY antibodies were developed against specific amino acid sequences present in IDS but absent in other human sulfatases. hrIDS produced in P. pastoris, commercial hrIDS, and normal human plasma samples were used as antigens and immunoquantification results were compared to enzyme activity. The technique was linear over the range 8 to 500 ng mL(-1) using commercial hrIDS. The concentration range detected for IDS in normal human plasma was 14.43 to 287.88 ng mL(-1). The hrIDS was detected in P. pastoris cultures even when the enzyme was inactive, which is convenient for monitoring the production of recombinant proteins. These results show that chicken site-specific antibodies provide a good alternative, as a substitute of monoclonal antibodies, for the detection of human proteins. This is the first report on the development of an ELISA system to detect and quantify IDS with IgY antibodies.

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In this study, the biodegradation of a mixture of 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) using the laccase produced by the white-rot fungus Trametes pubescens CBS 696.94 was evaluated. Two laccase isoenzymes with molecular weights of about 60 and 120 kDa were identified in the enzymatic crude extract. The highest laccase activity with syringaldazine was observed with pH 6.0 and 60°C, while with 2,2-azino-bis(3-ethylbenzothiazoline-6) sulphonic acid the highest activity was observed between 50 and 60°C and 3.0-4.0 pH. A biodegradation of 100%, 99%, 82.1% and 41.1% for 2-CP, 2,4-DCP, 2,4,6-TCP and PCP, respectively, was observed after 4h of reaction. The reduction in chlorophenols concentration allowed 90% reduction in mixture toxicity. In summary, these results show the feasibility of a laccase enzymatic crude extract from T. pubescens for the reduction of concentration and toxicity of chlorophenols.

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Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive disorder caused by N-acetylgalactosamine-6-sulfate sulfatase (GALNS) deficiency. Currently no effective therapies exist for MPS IVA. In this work, production of a recombinant GALNS enzyme (rGALNS) in Escherichia coli BL21 strain was studied. At shake scale, the effect of glucose concentration on microorganism growth, and microorganism culture and induction times on rGALNS production were evaluated. At bench scale, the effect of aeration and agitation on microorganism growth, and culture and induction times were evaluated. The highest enzyme activity levels at shake scale were observed in 12 h culture after 2-4 h induction. At bench scale the highest enzyme activity levels were observed after 2 h induction. rGALNS amounts in inclusion bodies fraction were up to 17-fold higher than those observed in the soluble fraction. However, the highest levels of active enzyme were found in the soluble fraction. Western blot analysis showed the presence of a 50-kDa band, in both soluble and inclusion bodies fractions. These results show for the first time the feasibility and potential of production of active rGALNS in a prokaryotic system for development of enzyme replacement therapy for MPS IVA disease.

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Morquio A is an autosomal recessive disease caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), leading to the lysosomal accumulation of keratan-sulfate and chondroitin-6-sulfate. We evaluated in HEK293 cells the effect of the cytomegalovirus immediate early enhancer/promoter (CMV) or the elongation factor 1alpha (EF1alpha) promoters, and the coexpression with the sulfatase modifying factor 1 (SUMF1) on GALNS activity. Four days postransfection GALNS activity in transfected cells with CMV-pIRES-GALNS reached a plateau, whereas in cells transfected with EF1alpha-pIRES-GALNS continued to increase until day 8. Co-transfection with pCXN-SUMF1 showed an increment up to 2.6-fold in GALNS activity. Finally, computational analysis of transcription factor binding-sites and CpG islands showed that EF1alpha promoter has long CpG islands and high-density binding-sites for Sp1 compared to CMV. These results show the advantage of the SUMF1 coexpression on GALNS activity and indicate a considerable effect on the expression stability using EF1alpha promoter compared to CMV.

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