15-Deoxi-∆12,14-prostaglandina J2 (15d-PGJ2) reduz a produção de IL-8 induzida por alérgenos do ácaro Dermatophagoides pteronyssinus em linhagem de queratinócitos humanos

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a high incidence worldwide. The pathogenesis of AD is complex, involving interactions between genetic susceptibility, changes in the skin barrier, immunological and environmental factors, especially exposure to the domestic dust mite such as Dermatophagoides pteronyssinus (Dpt). Keratinocytes participate in the immunoregulation of AD, through secretion of cytokines, chemokines and expression of receptors involved in inflammatory reactions. The human skin expresses the three types of PPAR receptors (PPARa, PPARP and PPARy).) PPAR agonists have anti-inflammatory properties because they reduce the expression of various proinflammatory cytokines, chemokines and cell adhesion molecules. Cyclopentenone 15-deoxy D 12, 14-PGJ 2 (15d-PGJ 2), an endogenous proliferator-activated peroxisome receptor (PPARy) intranuclear receptor ligand has already shown anti-inflammatory effects in different cell lines. The objective of this study was to evaluate the immunomodulatory capacity of 15d-PGJ2 in the production of inflammatory cytokines mediated by the Dpt extract in human keratinocyte line (HaCat cells). Dithiotreitol-DTT (aDpt) activated Dpt or Dpt treatment induced the production of IL-8 in a dose-dependent manner, being aDpt the most potent inducer IL-8. Pretreatment with 15d-PGJ2 showed a significant reduction of IL-8 and IL-6 levels induced by aDpt. We conclude that pre-treatment with 15d-PGJ2 promotes the down- regulation of aDpt-induced IL-8 and IL-6 production in HaCat cells, allowing further use in the development of novel therapies for the disease.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisDissertação (Mestrado)A dermatite atópica (DA) é uma doença inflamatória crônica da pele com alta incidência a nível mundial. A patogênese da DA é complexa, envolve interações entre susceptibilidade genética, alterações da barreira da pele, fatores imunológicos e ambientais, especialmente a exposição ao ácaro da poeira doméstica, como Dermatophagoides pteronyssinus (Dpt). Os queratinócitos participam da imunorregulação da DA, através da secreção de citocinas e quimiocinas e expressão de receptores envolvidos em reações inflamatórias. A pele humana expressa os três tipos de receptores PPAR (PPARa, PPARP e PPARy). Os agonistas PPAR apresentam propriedades anti-inflamatórias, pois reduzem a expressão de várias citocinas pró- inflamatórias, quimiocinas e moléculas de adesão celular. A prostaglandina ciclopentenona 15-desoxi D 12, 14-PGJ 2 (15d-PGJ 2), um ligante de receptor intranuclear de peroxissoma ativado por proliferador endógeno (PPARy) já tem mostrado efeitos anti-inflamatórios em diferentes linhagens celulares. Por isso, o objetivo desse estudo foi avaliar a capacidade imunomoduladora de 15d-PGJ2 na produção de citocinas inflamatórias mediadas pelo extrato de Dpt em linhagem de queratinócitos humanos (células HaCat). O tratamento com Dpt ou Dpt ativado por ditiotreitol - DTT (aDpt) induziu a produção de IL-8 de uma maneira dependente da dose, sendo aDpt indutor mais potente da IL-8. O pré-tratamento com 15d-PGJ2 mostrou uma redução significativa dos níveis de IL-8 e IL-6 induzidos por aDpt. Concluímos que o pré-tratamento com 15d-PGJ2 promove a regulação negativa da produção de IL-8 e IL-6 induzida por aDpt em células HaCat, permitindo uma posterior utilização no desenvolvimento de novas terapias para a doença

Comparative Detection of Immunoglobulin Isotypes and Subclasses against Toxoplasma gondii Soluble Antigen in Serum and Colostrum Samples from Puerperal Women

Background: Toxoplasma gondii is an obligate intracellular parasite that can infect several species, including humans, and can cause severe damage to the fetus when the infection occurs during pregnancy. The environment and/or food contamination are critical to spreading the infection. Human milk is rich in nutrients and bioactive elements that provide growth and development of the immune system of the newborn. All isotypes of immunoglobulins are present in human colostrum and they are produced from systemic or local sources. Breastfeeding protects the infant against various pathogens, but there is no conclusive study to detect IgG subclasses in colostrum against T. gondii. Therefore, the aim of this study was to detect and evaluate the presence of antibody isotypes against T. gondii in paired samples of serum and colostrum. Methods: The study included 283 puerperal patients. ELISA (Enzyme-Linked Immunosorbent Assay) for detection of anti-T. gondii-specific IgM, IgA, and IgG isotypes and IgG1, IgG3, and IgG4 subclasses were conducted on paired samples of serum and colostrum. Results: It was found that 45.9%, 6.0%, and 2.1% of serum samples and 45.2%, 7.1%, and 2.1% of colostrum samples were positive for IgG, IgM, and IgA, respectively. Specific IgG1, IgG3, and IgG4 were positive, respectively, in 98.5%, 54.6%, and 44.6% of serum samples, in contrast with 56.9%, 78.5%, and 34.6% of colostrum samples. Thus, the predominant reactivity of IgG subclasses against T. gondii was IgG1 in serum and IgG3 in colostrum. The higher percentage of positive samples and higher levels of anti-T. gondii IgG3 antibodies were observed in colostrum, when compared to serum samples, suggesting a local production of this subclass. IgG3 and IgG1 subclasses presented different percentages of positivity in serum and colostrum. Only the IgG1 subclass showed a significant correlation between the levels of anti-T. gondii in serum and colostrum, suggesting that IgG1 in breast milk comes from a systemic source. IgG4 showed a similar percentage of positivity in both sample types, but no significant correlation was observed between their levels. Conclusion: Colostrum presents representative levels of IgM, IgA, IgG1, IgG3, and IgG4 antibodies specific to T. gondii. The detection of these antibodies presents the potential for diagnostic application of colostrum samples to better identify the diagnostic status of T. gondii infection, especially during the acute phase. In addition, breastfeeding can also be a possible source of protective antibodies for the newborn against toxoplasmosis, an anthropozoonosis maintained by environmental infection, which interferes in the public health of many countries