The distribution and chemical coding of enteroendocrine cells in Trypanosoma cruzi-infected individuals with chagasic megacolon.

Chagas disease is caused by the parasite, Trypanosoma cruzi that causes chronic cardiac and digestive dysfunction. Megacolon, an irreversible dilation of the left colon, is the main feature of the gastrointestinal form of Chagas disease. Patients have severe constipation, a consequence of enteric neuron degeneration associated with chronic inflammation. Dysmotility, infection, neuronal loss and a chronic exacerbated inflammation, all observed in Chagas disease, can affect enteroendocrine cells (EEC) expression, which in turn, could influence the inflammatory process. In this study, we investigated the distribution and chemical coding of EEC in the dilated and non-dilated portion of T. cruzi-induced megacolon and in non-infected individuals (control colon). Using immunohistochemistry, EECs were identified by applying antibodies to chromogranin A (CgA), glucagon-like peptide 1 (GLP-1), 5-hydroxytryptamine (5-HT), peptide YY (PYY) and somatostatin (SST). Greater numbers of EEC expressing GLP-1 and SST occurred in the dilated portion compared to the non-dilated portion of the same patients with Chagas disease and in control colon, but numbers of 5-HT and PYY EEC were not significantly different. However, it was noticeable that EEC in which 5-HT and PYY were co-expressed were common in control colon, but were rare in the non-dilated and absent in the dilated portion of chagasic megacolon. An increase in the number of CgA immunoreactive EEC in chagasic patients reflected the increases in EEC numbers summarised above. Our data suggests that the denervation and associated chronic inflammation are accompanied by changes in the number and coding of EEC that could contribute to disorders of motility and defence in the chagasic megacolon.

Cervical cancer patients that respond to chemoradiation therapy display an intense tumor infiltrating immune profile before treatment.

Cervical cancer (CC) is a major cause of death and suffering to women globally with 570,000 new cases in 2017. It disproportionately affects those living in resource-constrained countries such as Brazil, with 90% of the deaths from CC happening in low and middle-income countries. Early detection is still the best strategy for improving response to therapy and survival and cases detected in advanced stages show variable response rates to the standard chemoradiation therapy protocols. Both the genetic landscape and the immune status of patients can dramatically affect cancer progression and response to therapy, as well as disease recurrence. Here we performed a comprehensive sequencing analysis using the cancer gene panel - Ion AmpliSeq™ Cancer hotspot Panel V2 CHPv2, as well as determined the immune infiltrate composition of a group of locally advanced CC patients with the goal of identifying genetic and immune characteristics associated with a clinical response to therapy. The expression levels of CD68+ tumor-associated macrophages (TAMs) and CD8+ tumor-infiltrating lymphocytes (TILs), as well as the immune checkpoint molecules PD-1, PD-L1 and PD-L2 in stroma and in tumor regions were analyzed by immunohistochemistry (IHC). The HPV infection status with high-risk strains was also determined. Twenty-one samples from patients with squamous cell carcinoma segregated into responder (11) and non-responder (10) groups according to standard chemoradiation therapy response were studied. Our findings indicate that responder patients showed an increase of an inflammatory tumor microenvironment as indicated by higher numbers of CD8+ and PD-L2+ TILs, as well as higher expression of PD-L1 immunoreactive area, as compared to the non-responder group. Additionally, our results demonstrate a correlation between the number of gene mutations and PD-L2+ TILs in the responder group. The genes PIK3CA and KDR/VEGFR were the most mutated genes, corroborating past findings. Together, these findings indicate an inflammatory tumor microenvironment present in patients that will respond to future chemoradiation treatment as compared to those that will not. This points to possible future predictors of response to therapy in CC patients.

Hookworm infection aggravates metabolic disorder in obesity.

Obesity and ancylostomiasis are considered public health problems. Recent studies have shown that infection by intestinal helminths in obese individuals can ameliorate metabolic disorder and improve glucose tolerance by decreasing both insulin resistance and low-intensity inflammation. However, few helminth species have been studied in this context, and some modulation mechanisms still require deeper investigation. Therefore, the present work aimed to investigate the role of experimental infection with Ancylostoma ceylanicum in the modulation of the immune response in an obese experimental model. Four groups of hamsters were used as follows: two groups were submitted to a hyperlipidic and hypercaloric diet capable of inducing obesity, one infected and the other uninfected; and two normonourished control groups, one infected and one uninfected by A. ceylanicum. Biochemical, haematological, parasitological and immunological parameters were evaluated. The results demonstrated that A. ceylanicum infection accentuated weight loss in obese animals compared to normonourished animals. However, obesity reduced the recovery of worms and oviposition of the females, and both infected groups showed decreased levels of haemoglobin, albumin, iron and erythrocytes. Significant relations were observed for pathogenesis in the following cases: infection interfered in lipid metabolism, which increased levels of total cholesterol and triglycerides in the obese group, and caused a decrease in HDL levels in both groups. Obesity led to an increase in glucose levels, and the infection exacerbated this parameter in both the normonourished and obese groups. Inflammation was intensified in obese animals that showed elevated macrophage and neutrophil activation in adipose tissue, enlargement of the spleen and accumulation of lipids in the liver and faeces. Despite the decrease in IFN-γ levels, the infection did not potentiated the expression of the Foxp3, IL-10 and IL-2 transcription factor for any of the infected groups, markers that could positively compensate the host from the damage caused by obesity.

Standardization and application of the tetraprimer ARMS-PCR technique for screening of the E198A SNP in the ß-tubulin gene of hookworm populations in Brazil.

The tetraprimer ARMS-PCR technique is efficient for SNP detection and can be used to search for polymorphisms associated with drug resistance. However, the establishment of this methodology is not always straightforward because of the constraints on primer design due to the restrictions of the polymorphic regions. Here, we describe the standardization of the tetraprimer ARMS-PCR methodology for the detection of a SNP at codon 198 of the Ancylostoma caninum ß-tubulin gene. This SNP is associated with resistance to albendazole in various nematodes. The methodology was used to screen 327 individuals from 6 different locations. No mutation was found in any of the samples. This methodology will be useful for screening for the E198A SNP in the ß-tubulin gene of canine hookworms in a broader population to determine whether this SNP is associated with benzimidazole resistance in this species. The method could also be adapted for the analysis of other SNPs in other nematode species.