Background The microbiota in the lumen of patients with Crohn’s disease (CD) is characterized by reduced diversity, particularly Firmicutes and Bacteroidetes. It is unknown whether the introduction of the intestinal microbiota from healthy individuals could correct this dysbiosis and reverse mucosal inflammation. We investigated the response to fecal microbial transplantation (FMT) from healthy individuals to subjects with active CD Methods We performed a prospective open-label study (uncontrolled) of FMT from healthy donors to subjects with active CD. A single FMT was performed via colonoscopy. Recipients’ microbial diversity, mucosal T-cell phenotypes and clinical and inflammatory parameters were measured over 12 weeks, and safety over 26 weeks. Results Nineteen subjects were treated with FMT and completed the study follow-up. Fifty-eight percent (11/19) demonstrated a clinical response (HBI decrease > 3) following FMT. Fifteen subjects had sufficient pre/post fecal samples for analysis. A significant increase in microbial diversity occurred after FMT (p=0.02). This was greater in clinical responders than non-responders. Patients who experienced a clinical response demonstrated a significant shift in fecal microbial composition towards their donor’s profile as assessed by the Bray-Curtis index at 4 weeks (p=0.003). An increase in regulatory T-cells (CD4+CD25+CD127lo) was also noted in recipients’ lamina propria following FMT. No serious adverse events were noted over the 26-week study period. Conclusion In this open label study, FMT led to an expansion in microbial bacterial diversity in patients with active CD. FMT was overall safe, although the clinical response was variable. Determining donor microbial factors that influence clinical response is needed prior to randomized clinical trials of FMT in CD. ClinicalTrials ID # NCT01847170

IBD is characterized by uncontrolled immune responses in inflamed mucosa, with dominance of IL-17-producing cells and deficiency of Treg cells. The aim of this study was to explore the effect and mechanisms of RA, the ligand of RARalpha, on immune responses in human and murine colitis. Colonic biopsies from patients with UC were cultured and treated with RA as the agonist of RARalpha or LE135 as the antagonist of RARalpha. Expressions of IL-17 and FOXP3 were detected by immunohistochemistry. Murine colitis was induced by intrarectal administration with TNBS at Day 1. Mice were then i.p.-treated with RA or LE135 daily for 7 days. Cytokine levels in the cultures of mouse LPMCs were measured. Expressions of FOXP3 and IL-17 in colon tissues or MLN were detected by immunohistological analysis. Body weight and colon inflammation were evaluated. RA treatment up-regulated FOXP3 expression and down-regulated IL-17 expression in colon biopsies of patients and in colon tissues and MLN of mice with colitis compared with controls. LPMCs from RA-treated mice produced lower levels of proinflammatory cytokines (TNF-alpha, IL-1beta, IL-17) but more regulatory cytokines (IL-10, TGF-beta) compared with that of untreated mice. LE135 showed the opposite effect of RA. Furthermore, RA ameliorated TNBS-induced colitis in a dose-dependent manner, as seen by improved body weight and colon inflammation. RA down-regulates colon inflammatory responses in patients with IBD in vitro and in murine colitis in vivo, representing a potential therapeutic approach in IBD treatment.

Among the many processes regulating cell death, ceramide signaling is a vital component. We previously determined that acid ceramidase (AC) is upregulated in 60% of primary prostate cancer (PCa) tissues, suggesting that AC may play a role in tumor development. In order to determine the significance of AC elevation, stable clones of DU145 cells with AC overexpression (AC-EGFP) were generated. Compared to controls (EGFP), AC-EGFP cells exhibited enhanced cell proliferation and migration. Subcutaneous injection of AC-EGFP cells into Nu/Nu mice resulted in larger tumor volumes compared to EGFP controls. Moreover, using the MTS viability assay, AC-EGFP cells were more resistant to cell death induced by doxorubicin, cisplatin, etoposide, gemcitabine or C6-ceramide. Conversely, knock down of AC using siRNA, sensitized AC-EGFP cells to these drugs. In addition, mass spectroscopic analysis of sphingolipids indicated that long chain ceramide levels were decreased in AC-EGFP cells treated with either doxorubicin or etoposide. In conclusion, this study implicates AC as a critical regulator of PCa progression by affecting not only tumor cell proliferation and migration but also responses to drug therapy, suggesting AC as a potential therapeutic target in advanced PCa.