Helminth infections and allergies are characterized by a predominant type-2 immune response. In schistosomiasis, the Th-2 response is usually accompanied by induction of immunoregulatory mechanisms that contribute to worm survival and less severe schistosomiasis. Although helminth-induced immunomodulatory mechanisms seem to affect atopy, epidemiological studies on the relationship between helminths and allergy have been inconsistent, and data suggest that the modulatory effects may be influenced by helminth species, chronicity of infection, and parasite burden. Here we performed a cross-sectional study to investigate the effects of Schistosoma mansoni parasite burden and immune response on allergic reactivity of individuals living in a schistosomiasis endemic area in Brazil. Fecal samples from the participants were collected for extensive parasitological examinations by spontaneous sedimentation, Kato-Katz, Helmintex and Saline Gradient tests and molecular detection of S. mansoni by qPCR. Additionally, the concentrations of cytokines and chemokines, total IgE and IgE-reactivity to common house dust allergens were quantified from serum samples. IgE reactivity to dust allergens was detected in 47 individuals (23.8%), and 140 individuals (54.4%) were diagnosed with S. mansoni infection. Most of the infected population (108 individuals) presented very low parasite burden (≤12 eggs/g of feces). The frequency and intensity (p ≤ 0.03) of allergic reactivity were lower in S. mansoni-infected compared with non-infected individuals. Multivariable logistic regression models adjusted by age revealed that allergic reactivity was positively associated with low IL-10 response (OR, 4.55, 95% CI, 0.56–7.36) and high concentration of the inflammatory mediators IL-33 (OR, 2.70, 95% CI, 1.02–7.15) or TNF-α (OR, 6.88, 95% CI, 0.32–143.39) in serum, and inversely associated with S. mansoni infection (OR, 0.38, 95% CI, 0.16–0.87). Most importantly, the logistic regression demonstrated that the modulatory effects of Schistosoma infection depend on parasite burden, with individuals infected with ≤12 eggs/g of feces showing allergic IgE-reactivity similar to non-infected individuals Altogether, our data show that immunomodulation of allergic reactivity depends on S. mansoni burden, low type-2 inflammatory response, and high level of IL-10.
Intestinal schistosomiasis, caused by the parasitic trematode Schistosoma mansoni, is a chronic disease and the prolonged and continuous exposure to S. mansoni antigens results in a deviation of the host's immune response. For diagnosis, the Kato-Katz (KK) method is recommended, however, this method showed low accuracy in areas of low endemicity. This study aimed to characterize the cytokine and chemokine profile of individuals with an extremely low parasite load (<4 eggs per gram of feces), e.g., individuals who were detected by alternative parasitological methods, such as the saline gradient and/or Helmintex®. In order to search for immunological markers for infection, the immunological profile in serum samples of these individuals was then compared with patients detected with the KK method and with a higher parasite load and with individuals repetitively negative by extensive stool exams. The study was conducted in Northern Minas Gerais in a rural area of the Municipality of Januária. Serum samples of a total of 139 parasitologically well-characterized individuals were assessed for the following immunological markers by commercially available immunoassays: TNF-α, IL-1β, IL-6, IL-17A, IL-5, IL-10, IL-13, IL-33, IL-27, CCL3, CCL5, CXCL10, CCL11, and CCL17. As a result, there were no significant differences in concentrations or frequencies for immunological markers between egg-negative individuals or individuals with ultra-low (<4 epg) or low (4–99 epg) parasite loads. However, we found significant correlations between egg counts and eosinophil counts and between egg counts and IL-1β or TNF-α concentrations. The most striking alterations were found in individuals with the highest parasite load (≥100 epg). They had significantly higher TNF-α concentrations in serum when compared with individuals with a low parasite load (4–99 epg) and CCL17 concentrations were significantly elevated when compared with egg-negative individuals. Radar diagrams of frequencies for cytokine and chemokine responders in each infection group confirmed a distinct profile only in the infection group with highest parasite loads (≥100 epg).
New O-isoprenylated-N-methylarylnitrones derived from isomeric o, m and p-hydroxybenzaldehydes have been prepared and the antineoplastic effects on human cancer cell lines were evaluated. The O-geranylated nitrone LQB-278 (1b) and its isomers 2b and 3b inhibited the NO production, but the anti-leukemic activity was drastically dependent on nitrone isomer, with the 1b being the most effective one (IC₅₀ of 6.7 μM) on Jurkat leukemia cell, by MTT assay. In addition, 1b up-regulated p21CIP1/WAF1/Sdi1 protein expression (flow cytometry), a cell cycle inhibitor, reduced cell growth, and induced DNA fragmentation (increased sub-G1 phase cells) and phosphatidylserine externalization in plasmatic membrane (increased annexin V positive cells). Finally, the 1b up-regulation of p21 expression and apoptosis induction seem to be the mechanisms by which it promotes its anti-leukemic effects, making this new molecular architecture a promising prototype for leukemia intervention.
RESUMO: Com o objetivo de diagnosticar a situação do complexo teníase-cisticercose bovina no município de Salinas, Minas Gerais, foram coletadas amostras de sangue de 355 bovinos distribuídos em 18 propriedades rurais, sorteadas aleatoriamente. Em cada propriedade, foi aplicado um questionário socioeconômico para a análise de fatores que favorecem a manutenção do complexo teníase-cisticercose bovina. Foi realizado também um levantamento epidemiológico dos casos de teníase diagnosticados nos laboratórios credenciados pela Secretaria Municipal de Saúde de Salinas, no período de 2007 a 2010. A prevalência de cisticercose bovina foi de 4,70% enquanto as prevalências de teníase, encontradas durante os quatro períodos avaliados, foram de 0,29%, 0,36%, 0,24% e 0,24%. Entre os fatores de risco para a manutenção do complexo teníase-cisticercose analisados, foi observada uma relação estatisticamente significativa entre a ocorrência de cisticercose bovina e a ingestão de carne malpassada pelos entrevistados. Foi concluído que a cisticercose bovina está presente no município de Salinas, Minas Gerais, sendo o tratamento térmico ineficiente da carne bovina o principal fator de risco para a manutenção do complexo teníase-cisticercose, o que reforça a necessidade da adoção de medidas de controle com contínua vigilância epidemiológica e sanitária.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.