Background: Inflammatory bowel disease (IBD) involves a breakdown in interactions between the host immune response and the resident commensal microbiota. Recent studies have suggested gut physiology and pathology relevant to human IBD can be rapidly modeled in zebrafish larvae. The aim of this study was to investigate the dysbiosis of intestinal microbiota in zebrafish models with IBD-like enterocolitis using culture-independent techniques.Results: IBD-like enterocolitis was induced by exposing larval zebrafish to trinitrobenzenesulfonic acid (TNBS). Pathology was assessed by histology and immunofluorescence. Changes in intestinal microbiota were evaluated by denaturing gradient gel electrophoresis (DGGE) and the predominant bacterial composition was determined with DNA sequencing and BLAST and confirmed by real-time polymerase chain reaction. Larval zebrafish exposed to TNBS displayed intestinal-fold architecture disruption and inflammation reminiscent of human IBD. In this study, we defined a reduced biodiversity of gut bacterial community in TNBS-induced coliitis. The intestinal microbiota dysbiosis in zebrafish larvae with IBD-like colitis was characterized by an increased proportion ofProteobacteria(especiallyBurkholderia) and a decreased of Firmicutes(Lactobacillus group), which were significantly correlated with enterocolitis severity(Pearson correlationp< 0.01).Conclusions: This is the first description of intestinal microbiota dysbiosis in zebrafish IBD-like models, and these changes correlate with TNBS-induced enterocolitis. Prevention or reversal of this dysbiosis may be a viable option for reducing the incidence and severity of human IBD.

Gastrointestinal bacteria and epithelia contribute to systemic inflammation and infections in critically ill patients, but the gut microbiota in these diseases has not been analyzed dynamically by molecular fingerprinting methods. This study aimed to identify ileal flora dysbiosis pattern and bacterial species that changed significantly in a rat model of intestinal ischemia and reperfusion and illustrate time courses of both epithelial alterations and gut flora variations in the same injury. Forty-eight rats were randomized into eight groups (n = 6/group). Six groups underwent superior mesenteric artery occlusion for 30 min and were killed at 1, 3, 6, 12, 24, and 72 h following reperfusion, respectively; a group of rats were killed just after anesthesia (control), and a sham-operated group received 12-h reperfusion. Denaturing gradient gel electrophoresis of ileal microbiota showed that gut flora pattern changed early after intestinal ischemia and reperfusion, differed significantly at 12 h of reperfusion, and then started to recover toward normal pattern. The specific dysbiosis were characterized by Escherichia coli proliferation and Lachnospiraceae and Lactobacilli reduction. These bacteria that contributed most were identified by principal component analysis and sequencing and confirmed by real-time polymerase chain reaction. In addition, alterations of ileal microbiota followed epithelial changes in the time course of reperfusion.

It is believed that inflammatory bowel disease (IBD) involves a breakdown in interactions between the resident commensal microbiota and the host immune response. Recent studies have revealed that gut physiology and pathology relevant to human IBD can be rapidly modeled in zebrafish larvae with a number of advantages compared with murine models. The objective of this study was to evaluate the role of gut microbiota in zebrafish models with IBD-like enterocolitis. IBD-like enterocolitis was induced by exposing larval zebrafish to 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). Assays were performed using larval zebrafish collected at 8 and 10 days postfertilization (dpf ). In the absence of gut microbiota, the TNBS-induced enterocolitis was less extensive. The expression of toll-like receptor 3 (TLR3) and the TLRs signaling pathway molecules MyD88 and TRIF, the activation of NF-κB, and the production of inflammatory cytokine tumor necrosis factor-α were stimulated in TNBS-treated zebrafish but there was no corresponding alteration in germ-free fish. With microbial colonization, all results reverted to a pattern similar to that observed in conventionally reared zebrafish. We described the key role of gut microbiota in the etiology of a chemically induced larval zebrafish IBD-like model, showing an involvement of TLR signaling pathways.

A total of 32 patients (25 with advanced MDS and 7 with t-AML) were enrolled in this study to evaluate the efficacy and toxicity of the low-dose cytarabine and homoharringtonine in combination with granulocyte colony-stimulating factor (G-CSF) (CHG protocol) in patients with advanced myelodysplastic syndromes (MDS) or MDS-transformed acute myeloid leukemia (t-AML). All the patients were administered the CHG regimen comprising low-dose cytarabine (25 mg/day, intravenous continuous infusion, days 1-14), homoharringtonine (1 mg/day, intravenous continuous infusion, days 1-14), and G-CSF (300 microg/day, subcutaneous injection, days 0-14, interrupted when the peripheral white blood cell count reached >20 x 10(9)/L). The overall response rate was 71.9% after the administration of one course of the CHG regimen. Of the 32 patients, 15 (46.9%) achieved complete remission (CR) and 8 (25%) achieved partial remission (PR). This regimen was followed by a post-remission therapy that included conventional chemotherapy, when CR was achieved. Of the patients with CR who just received post-remission regimens as homoharringtonine and cytarabine (HA) and daunorubicin and cytarabine (DA) 6 relapsed rapidly and just had a mean 6.1 months of CR. Otherwise, the other 8 out of 14 patients with CR alternatively received subsequent chemotherapy, which combined mitoxantrone, idarubicin, pirarubicin, or aclarubicin with cytarabine. The mean CR duration of the 8 patients had reached 10.6 months, and 5 of the 8 still kept a continuous CR. The median overall survival (OS) was 18.2 months. There were no statistically significant differences for CR, PR, and OS when the patients were grouped by age, blasts in bone marrow, and karyotypes, respectively. No treatment-related deaths were observed. Myelosuppression was mild to moderate, and no severe non-hematological toxicity was observed. Thus, a CHG priming regimen as an induction therapy was well tolerated and effective in patients with advanced MDS or t-AML. Stronger and alternative subsequent chemotherapy is necessary for patients with CR to maintain longer CR and better OS.

We aimed to investigate the prognostic value of the immune cells population in peripheral blood from patients with advanced gastric cancer treated with neoadjuvant chemotherapy. A total of 105 patients with advanced gastric cancer were evaluated in this study. Blood samples were collected before and 1 week after the last dose of chemotherapy. The percentage of CD3+, CD3+CD4+, CD3+CD8+, and CD4+CD25+Foxp3+ T cells was assessed using flow cytometry analysis. The relationship between T cell subsets and clinical outcome was evaluated. The percentage of CD3+CD8+ lymphocytes was significantly increased after chemotherapy and CD4+CD25+Foxp3+ regulatory T cells (Tregs) decreased (p = 0.003 and p < 0.001, respectively). The percentage of CD3+CD8+ lymphocytes and Tregs was strongly associated with response to chemotherapy (p = 0.017 and p < 0.030, respectively). Patients with high CD3+CD8+ T cells and low CD4+CD25+Foxp3+ Tregs had significantly increased overall survival (p = 0.012 and p = 0.048, respectively). Neither CD3+ nor CD3+CD4+ T cells showed significant changes after chemotherapy or correlations with the clinical outcome. The positive correlation between a high CD3+CD8+ T cells or low CD4+CD25+Foxp3+ Tregs and clinical outcome indicates its key role in the prognosis of gastric cancer patients and may serve as a biomarker to identify patients likely to benefit from neoadjuvant chemotherapy.