Resposta de anticorpos IgE, IgG1 e IgG4 aos componentes ligantes de Concanavalina A isolados de Blomia tropicalis (Acari: Echimyopodidae) em indivíduos alérgicos e não alérgicos

Blomia tropicalis (Bt) and Dermatophagoides pteronyssinus (Dp) are the most prevalent house dust mites in tropical countries and associated with allergic diseases. Glycosilated antigens are highly immunogenic and involved in different pathologies, including allergies. The aims of this study were to evaluate IgE, IgG1, and IgG4 responses to Concanavalin A-binding components (Bt-ConA) isolated from Bt extract in sera of allergic and non-allergic subjects and to analyze the crossreactivity with Dp extract. Also, IgE-, IgG1- and IgG4-reactive antigenic components from both extracts were analyzed by Immunoblotting. Bt-ConA was obtained from Btwhole extract fractionated on Con-A-Sepharose affinity chromatography and both extracts were evaluated in SDS-PAGE and ELISA for IgE, IgG1, and IgG4 in sera of 121 patients with allergic rhinitis and 36 non-allergic subjects. Subjects were skin prick tested (SPT) to Bt-whole extract. Inhibition and immunoblotting test were performed to analyze IgE, IgG1, and IgG4 responses to both extracts. SPT showed that 58% of patients were sensitized to Bt (Bt+), with 52% reactive to both mites (Bt and Dp) and 6% to Bt only. A broad spectrum of proteins (14-152kDa) were visualized in Bt-whole extract and components >27kDa in Bt-ConA extract. ELISA showed a similar profile of IgE, IgG1 and IgG4 levels to Bt-whole and Bt-ConA extracts in different groups, although Bt+ patients showed a lower IgG4 reactivity to Bt-ConA extract. Specific IgG1 levels were higher in Bt+ patients than control subjects, and IgG4 levels showed no significant difference among the groups. ELISA inhibition showed a partial IgE and total IgG1 and IgG4 cross-reactivity with Dp extract for Bt-whole and Bt-ConA extracts. Immunoblotting revealed ten antigenic components in Bt-whole extract (14-152kDa) recognized by IgE and IgG4 antibodies and five of these components (>50kDa) were recognized by IgG1 in Bt+ patients. Bt- ConA extract showed eight antigenic components (27-152kDa), from which the 152 and 123kDa bands were predominantly recognized by IgE, and only three of these components (93, 123 and 152kDa) were recognized by IgG1 while IgG4 antibodies weakly recognized the 66 and 152kDa components in Bt+ patients. It can be concluded that Con A-binding components isolated from Bt constitute major allergens and are involved in both allergen sensitization (IgE response) and homeostase maintenance (IgG1 and IgG4 responses) and that glycosilated components, particularly those of high molecular weight, are preferentially recognized by IgE and IgG1, but not by IgG4 antibodies.Mestre em Ciências da SaúdeBlomia tropicalis (Bt) e Dermatophagoides pteronyssinus (Dp) são os principais ácaros da poeira domiciliar em países tropicais e subtropicais que estão associados com doenças alérgicas. Antígenos glicosilados são altamente imunogênicos e estão envolvidos em diferentes patologias, incluindo alergias. Os objetivos deste estudo foram avaliar a resposta de anticorpos IgE, IgG1 e IgG4 a componentes ligantes de Concanavalina A (Bt-ConA) isolados do extrato Bt total em soros de indivíduos alérgicos e não alérgicos, bem como a reatividade cruzada com Dp e identificar por immunoblotting componentes protéicos de ambos extratos reconhecidos por anticorpos IgE, IgG1 e IgG4. O extrato Bt-ConA foi obtido por fracionamento do extrato Bt total em cromatografia de afinidade Con A-Sepharose e ambos extratos foram avaliados em SDS-PAGE e ELISA para IgE, IgG1 e IgG4 em 121 soros de pacientes com rinite alérgica e 36 indivíduos não alérgicos. Testes cutâneos de puntura (TCP) foram realizados em todos os indivíduos do estudo. Ensaios de inibição foram realizados para detecção de IgE, IgG1 e IgG4 específica a Bt total e Bt-ConA. Ensaios de immunoblotting foram realizados para detecção de componentes antigênicos de ambos extratos reconhecidos por IgE, IgG1 e IgG4. Do total de 121 pacientes, 58% mostraram-se sensibilizados a Bt (Bt+), com 52% apresentando reatividade cutânea a ambos ácaros (Bt e Dp) e apenas 6% somente a Bt. Um largo espectro de proteínas (14-152kDa) foram visualizadas no extrato Bt total e componentes acima de 27kDa na fração Bt-ConA. ELISA apresentou um perfil similar nos níveis de IgE, IgG1 e IgG4 para os extratos Bt total e Bt-ConA em diferentes grupos, embora pacientes do grupo Bt+ demonstraram uma reatividade menor de IgG4 para o extrato Bt-ConA. Níveis de IgG1 específica foram maiores nos pacientes Bt+ do que nos indivíduos controles e os níveis de IgG4 não apresentaram diferença significativa entre os grupos. ELISA de inibição demonstrou uma reatividade cruzada parcial com o extrato de Dp para IgE específica e total para IgG1 e IgG4 específicas aos extratos de Bt total e Bt-ConA. Immunoblotting revelou dez componentes antigênicos do extrato Bt total (14-152kDa) reconhecidos por anticorpos IgE e IgG4 e cinco destes componentes (>50kDa) foram reconhecidos por IgG1 em pacientes Bt+. O extrato Bt-ConA revelou oito componentes antigênicos (27-152kDa), dos quais as bandas de 152 e 123kDa foram predominantemente reconhecidos por IgE e apenas três destes componentes (93, 123 e 152kDa) foram reconhecidos por IgG1 enquanto anticorpos IgG4 reconheceram fracamente os componentes de 66 e 152kDa em pacientes Bt+. Pode-se concluir que componentes ligantes de Con-A isolados de Bt constituem alérgenos principais e estão envolvidos tanto na sensibilização alergênica (resposta IgE) quanto na manutenção da homeostase (respostas IgG1 e IgG4) e que componentes glicosilados, particularmente os de alto peso molecular, são preferencialmente reconhecidos por anticorpos IgE e IgG1, mas não por anticorpos IgG4

An eco-friendly enantioselective access to (R)-Naringenin as inhibitor of proinflammatory cytokine release.

(R/S)-Naringenin is a flavanone, well-known for its beneficial health-related properties, such as anti-inflammatory activity. The preparative enantioselective chromatographic resolution of commercial (R/S)-Naringenin was performed on Chiralpak® AD-H column (500 x 50 mm I.D., dp = 20 μm) using methanol as eluent. The developed method is in accordance with the principles of green chemistry, since the environmental impact was lowered through the recycle of eluent. In this way, g-amounts of each enantiomer were recovered with high purity (chemical purity > 99%, enantiomeric excess > 94%). The racemic and enantiomeric Naringenin were subjected to an exhaustive in vitro investigation of anti-inflammatory activity, aimed at evaluating the relevance of chirality. The assay on cultured human peripheral blood mononuclear cells activated by Phytohemagglutinin A revealed that (R)-Naringenin is the most effective in inhibiting the T-cell proliferation, showed to be still active at lowest concentration. Moreover, (R)-Naringenin significantly reduced pro-inflammatory cytokines levels such as TNF-α and, with less potency, IL-6. These results evidenced the anti-inflammatory potential of Naringenin and the highest capacity of (R)-Naringenin to inhibit both in vitro PBMC proliferation and cytokines secretion at non toxic doses. Thus, (R)-Naringenin is a promising candidate for in vivo investigation

An eco-friendly enantioselective access to (R)-Naringenin as inhibitor of proinflammatory cytokine release.

(R/S)-Naringenin is a flavanone, well-known for its beneficial health-related properties, such as anti-inflammatory activity. The preparative enantioselective chromatographic resolution of commercial (R/S)-Naringenin was performed on Chiralpak® AD-H column (500 x 50 mm I.D., dp = 20 μm) using methanol as eluent. The developed method is in accordance with the principles of green chemistry, since the environmental impact was lowered through the recycle of eluent. In this way, g-amounts of each enantiomer were recovered with high purity (chemical purity > 99%, enantiomeric excess > 94%). The racemic and enantiomeric Naringenin were subjected to an exhaustive in vitro investigation of anti-inflammatory activity, aimed at evaluating the relevance of chirality. The assay on cultured human peripheral blood mononuclear cells activated by Phytohemagglutinin A revealed that (R)-Naringenin is the most effective in inhibiting the T-cell proliferation, showed to be still active at lowest concentration. Moreover, (R)-Naringenin significantly reduced pro-inflammatory cytokines levels such as TNF-α and, with less potency, IL-6. These results evidenced the anti-inflammatory potential of Naringenin and the highest capacity of (R)-Naringenin to inhibit both in vitro PBMC proliferation and cytokines secretion at non toxic doses. Thus, (R)-Naringenin is a promising candidate for in vivo investigation

Identification of peptides with ELAV-like mRNA-stabilizing effect: an integrated in vitro/in silico approach

Embryonic lethal abnormal vision (ELAV) proteins are RNA-binding proteins that bind specific adenine and uridine-rich elements mainly located in the 3'-untranslated region of target mRNAs, preventing their otherwise rapid degradation and thus increasing gene expression. Starting from our previous discovery and applying an integrated in vitro/in silico approach, herein we report a deeper understanding of the mRNA-stabilizing activity of four peptides derived from the ELAV proteins structure. The stabilizing effect on the VEGF transcript (mRNAVEGF ) exerted by each peptide, tested individually, was initially evaluated, and no effects were evidenced. Hence, the biological effects of all peptides couples were investigated. Interestingly, in accordance with preliminary molecular dynamics results, only one of all possible peptide couples resulted highly effective in stabilizing mRNAVEGF . These two peptides were thus identified as valuable starting point for designing small molecules with ELAV-mimicking properties

Are sigma modulators an effective opportunity for cancer treatment? A patent overview (1996-2016).

Introduction: Although several molecular targets against cancer have been identified, there is a continuous need for new therapeutic strategies. Sigma Receptors (SRs) overexpression has been recently associated with different cancer conditions. Therefore, novel anticancer agents targeting SRs may increase the specificity of therapies, overcoming some of the common drawbacks of conventional chemotherapy. Areas covered: The present review focuses on patent documents disclosing SR modulators with possible application in cancer therapy and diagnosis. The analysis reviews patents of the last two decades (1996–2016); patents were grouped according to target subtypes (S1R, S2R, pan-SRs) and relevant Applicants. The literature was searched through Espacenet, ISI Web, PatentScope and PubMed databases. Expert opinion: The number of patents related to SRs and cancer has increased in the last twenty years, confirming the importance of this receptor family as valuable target against neoplasias. Despite their short history in the cancer scenario, many SR modulators are at pre-clinical stage and one is undergoing a phase II clinical trial. SRs ligands may represent a powerful source of innovative antitumor therapeutics. Further investigation is needed for validating SR modulators as anti-cancer drugs. We strongly hope that this review could stimulate the interest of both Academia and pharmaceutical companies