Consumption of gluten with gluten-degrading enzyme by celiac patients: A pilot-study

AIM:To assesses the safety and efficacy of Aspergillus niger prolyl endoprotease(AN-PEP)to mitigate the im-munogenic effects of gluten in celiac patients.METHODS:Patients with initial diagnosis of celiac disease as confirmed by positive serology with subtotal or total villous atrophy on duodenal biopsies who adhere to a strict gluten-free diet(GFD)resulting in normalised antibodies and mucosal healing classified as Marsh 0 orⅠwere included.In a randomised double-blind placebo-controlled pilot study,patients consumed toast(approximately 7 g/d gluten)with AN-PEP for 2 wk(safety phase).After a 2-wk washout period with adherence of the usual GFD,14 patients were randomised to gluten intake with either AN-PEP or placebo for 2 wk(efficacy phase).Measurements at baseline included complaints,quality-of-life,serum antibodies,immunophenotyping of T-cells and duodenal mucosa immunohistology.Furthermore,serum and quality of life questionnaires were collected during and after the safety,washout and efficacy phase.Duodenal biopsies were collected after the safety phase and after the efficacy phase.A change in histological evaluation according to the modified Marsh classification was the primary endpoint.RESULTS:In total,16 adults were enrolled in the study.No serious adverse events occurred during the trial and no patients withdrew during the trial.The mean score for the gastrointestinal subcategory of the celiac disease quality(CDQ)was relatively high throughout the study,indicating that AN-PEP was well tolerated.In the efficacy phase,the CDQ scores of patients consuming gluten with placebo or gluten with AN-PEP did not significantly deteriorate and moreover no differences between the groups were observed.During the efficacy phase,neither the placebo nor the AN-PEP group developed significant antibody titers.The IgA-EM concentrations remained negative in both groups.Two patients were excluded from entering the efficacy phase as their mucosa showed an increase oftwo Marsh steps after the safety phase,yet with undetectable serum antibodies,while 14 patients were considered histologically stable on gluten with AN-PEP.Also after the efficacy phase,no significant deterioration was observed regarding immunohistological and flow cytometric evaluation in the group consuming placebo compared to the group receiving AN-PEP.Furthermore,IgA-tTG deposit staining increased after 2 wk of gluten compared to baseline in four out of seven patients on placebo.In the seven patients receiving AN-PEP,one patient showed increased and one showed decreased IgA-tTG deposits.CONCLUSION:AN-PEP appears to be well tolerated.However,the primary endpoint was not met due to lack of clinical deterioration upon placebo,impeding an effect of AN-PEP.

The DNA-binding factor Ctcf critically controls gene expression in macrophages

Macrophages play an important role in immunity and homeostasis. Upon pathogen recognition via specific receptors, they rapidly induce inflammatory responses. This process is tightly controlled at the transcriptional level. The DNA binding zinc-finger protein CCCTC-binding factor （Ctcf） is a crucial regulator of long-range chromatin interactions and coordinates specific communication between transcription factors and gene expression processes. In this study, the Ctcf gene was specifically deleted in myeloid cells by making use of the transgenic Cre-LoxP system. Conditional deletion of the Ctcfgene in myeloid cells induced a mild phenotype in vivo. Ctcf-deficient mice exhibited significantly reduced expression of major histocompatibility complex （MHC） class II in the liver. Ctcf-deficient macrophages demonstrated a normal surface phenotype and phagocytosis capacity. Upon Toll-like receptor （TLR） stimulation, they produced normal levels of the pro-inflammatory cytokines IL-12 and IL-6, but manifested a strongly impaired capacity to produce tumor-necrosis factor （TNF） and IL-IO, as well as to express the IL-IO family members IL-19, IL-20 and IL-24. Taken together, our data demonstrate a role of Ctcf that involves fine-tuning of macrophage function.