Current Espghan Guidelines for Celiac Disease in Pediatric Age, Tertiary Care Center Experience: A Proposal for Further Simplification.

According to the 2012 ESPGHAN criteria for diagnosis of celiac disease (CD), duodenal biopsy (DB) can be avoided in children with a clear malabsorption syndrome, anti-tissue transglutaminase IgA (tTG2) ≥ 10x the cut-off, anti-endomysium IgA (EMA) and HLA DQ2/DQ8 genes. The aim of this study is to report our experience and evaluate the accuracy of the actual guidelines. PATIENTS AND METHODS: This is a retrospective study conducted on all patients diagnosed CD from 2012 to 2018 in our Center. For all patients enrolled were analyzed: data of family history, symptoms, serology, genetics, Marsh grade and follow-up. RESULTS: A total of 481 children [mean age 6,4 yrs; F:M= 1.8:1] were included in the study. The mean age of patients who were not subject to DB was lower (4.51 yrs) comparing with patients that received DB (6.48 yrs). Out of the 256 patients with anti-tTG2 ≥ 10 fold, 121 underwent DB because of mild symptoms (84/121) or no symptoms (37/121). In all cases Marsh type 3 was found and HLA haplotypes was compatible with CD diagnosis. CONCLUSIONS: Our study confirms that the serology has a primary importance to diagnose CD, regardless of the symptoms. These data suggest that biopsy and HLA haplotypes search, in presence of anti-tTG2 IgA ≥ 10x the cut-off, are wasteful and unhelpful for the patients.

Analysis of lactase processing in rabbit.

The proteolytic processing of rabbit intestinal lactase-phlorizin-hydrolase (LPH) was studied by pulse-chase and continuous labeling experiments in organ culture from 15-day-old rabbits in the presence of glycosylation and processing inhibitors. Monensin and brefeldin A inhibited the two proteolytic cleavages of the precursor indicating that they are post-Golgi events as previously reported for the unique cleavage of LPH in man. The inhibition was not related to a concomitant alteration glycosylation; in fact, if trimming was blocked by MDNM the abnormal glycosylated precursor was proteolytically processed normally. Finally the use of the anti-microtubular drug colchicine strongly inhibited both cleavages and caused accumulation of the complex-glycosylated precursor form the brush border fraction indicating that proteolytic events depend on intact microtubule (transport).

In vitro biosynthesis of lactase in suckling and adult rabbits. Regulatory mechanisms involved in the decline of the lactase activity.

Steady state forms, levels and the in vitro biosynthesis of lactase-phlorizin hydrolase (LPH) proteins have been studied in proximal and middle intestine of suckling and adult rabbits. In most adult tissues the lactase activity and the LPH protein content were low and the synthesis rate of the 200 kDa lactase precursor was reduced in comparison to suckling tissues. In a few tissues with low enzymatic activity the LPH protein content was relatively high, and high lactase synthesis occurred. In addition, the ratio (labeled lactase)/(lactase protein) was lower in the middle jejunum of the adult rabbit than in the proximal region. Both decreased synthesis of LPH precursor and increased turnover or inactivation of the enzyme may cause the decline of the lactase activity.

Recombinant human interleukin 10 suppresses gliadin dependent T cell activation in ex vivo cultured coeliac intestinal mucosa.

BACKGROUND: Enteropathy in coeliac disease (CD) is sustained by a gliadin specific Th1 response. Interleukin (IL)-10 can downregulate Th1 immune responses. AIM: We investigated the ability of recombinant human (rh) IL-10 to suppress gliadin induced Th1 response. PATIENTS AND METHODS: IL-10 RNA transcripts were analysed by competitive reverse transcription-polymerase chain reaction in duodenal biopsies from untreated and treated CD patients, non-coeliac enteropathies (NCE), and controls. CD biopsies were cultured with a peptic-tryptic digest of gliadin with or without rhIL-10. The proportion of CD80+ and CD25+ cells in the lamina propria, epithelial expression of Fas, intraepithelial infiltration of CD3+ cells, as well as cytokine synthesis (interferon gamma (IFN-gamma) and IL-2) were measured. Short term T cell lines (TCLs) obtained from treated CD biopsies cultured with gliadin with or without rhIL-10 were analysed by ELISPOT for gliadin specific production of IFN-gamma. RESULTS: In untreated CD and NCE, IL-10 RNA transcripts were significantly upregulated. In ex vivo organ cultures, rhIL-10 downregulated gliadin induced cytokine synthesis, inhibited intraepithelial migration of CD3+ cells, and reduced the proportion of lamina propria CD25+ and CD80+ cells whereas it did not interfere with epithelial Fas expression. In short term TCLs, rhIL-10 abrogated the IFN-gamma response to gliadin. CONCLUSIONS: rhIL-10 suppresses gliadin specific T cell activation. It may interfere with the antigen presenting capacity of lamina propria mononuclear cells as it reduces the expression of CD80. Interestingly, rhIL-10 also induces a long term hyporesponsiveness of gliadin specific mucosal T cells. These results offer new perspectives for therapeutic strategies in coeliac patients based on immune modulation by IL-10.

Interleukin 18 and associated markers of T helper cell type 1 activity in coeliac disease.

BACKGROUND: Coeliac disease (CD) is caused by a T helper cell type 1 (Th1) response in the small intestinal mucosa to dietary gluten. Paradoxically, interleukin (IL)-12, the major Th1 inducing factor, is undetectable in the mucosa of active CD. IL-18 is a recently described cytokine capable of promoting T cell interferon (IFN)-gamma production and facilitating Th1 cell polarisation. AIM: To examine expression of IL-18 and IL-18-associated Th1 proteins in CD. METHODS: IL-18 and IFN-gamma RNA transcripts were determined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). IL-18 and caspase-1 protein expression were assessed by western blotting. Caspase-1 activity was determined using a commercially available assay. RNA transcripts for the IL-18 receptor subunits, IL-1 receptor related protein (IL-1 Rrp) and accessory protein-like subunit (AcPL), and IL-18 induced Th1 specific T box transcription factor (T-bet) were measured by RT-PCR and Southern blotting. RESULTS: IL-18 RNA transcripts were found in all mucosal samples analysed, with no difference between CD patients and controls. By western blot analysis, a large protein of approximately 24 kDa, corresponding to the immature IL-18, was detected in all mucosal samples from CD patients and controls. In contrast, mature IL-18 was only seen in CD patients. Immunoreactivity corresponding to both immature and mature caspase-1 was present in both CD and control samples. Tissue homogenates from CD patients and controls expressed similar levels of caspase-1 activity. IL-1Rrp and AcPL were seen in all samples but were expressed at greater levels in the mucosa of CD patients. T-bet was also upregulated in CD. CONCLUSIONS: Active IL-18 is expressed in CD as well as other markers of Th1 polarisation.

Keratinocyte growth factor and coeliac disease.

BACKGROUND: Coeliac disease is characterised by increased epithelial renewal associated with a mucosal T cell response to gliadin. Keratinocyte growth factor (KGF) is produced by cytokine activated gut stromal cells and may be a link between mucosal T cell activation in untreated coeliac disease and epithelial hyperplasia. AIMS: To characterise expression of KGF in coeliac disease. METHODS: KGF transcripts in coeliac disease were measured by quantitative competitive reverse transcription-polymerase chain reaction (RT-PCR) and localised using in situ hybridisation. KGF production by gluten reactive CD4+ T cell clones was examined. In addition, KGF transcripts were measured following ex vivo challenge of coeliac biopsies with a peptic-tryptic digest of gliadin. RESULTS: KGF transcripts were elevated in coeliac biopsies compared with normal controls but were not different from non-coeliac disease controls. By in situ hybridisation, KGF mRNA containing cells were present in the upper half of the lamina propria, most abundantly just under the epithelium. There was no signal from cells within the epithelium. Gluten reactive T cell clones did not make KGF. In vitro challenge of coeliac biopsies generated a strong interferon gamma response but a specific KGF response could not be detected because of an extremely high number of KGF transcripts in all cultured biopsies. CONCLUSIONS: KGF is overexpressed in coeliac biopsies and in tissues with non-coeliac enteropathy. No evidence was found for KGF production by intraepithelial lymphocytes or lamina propria T cells.

Lactase persistence versus decline in human adults: multifactorial events are involved in down-regulation after weaning.

BACKGROUND & AIMS: In nonhuman mammals, lactase activity declines during or after weaning. In contrast, about one half of the human species maintains high lactase activity even in adulthood. To clarify this difference, this study examined some parameters for which contrasting observations have been reported in connection with lactase decline. METHODS: Lactase activity, lactase messenger RNA (mRNA) levels, and in vitro lactase biosynthesis were determined in normal jejunal samples from a large group of white adults, all born in or near Naples. RESULTS: Of 44 individuals, 10 were lactase persistent and 34 were hypolactasic. Biosynthesis of prolactase correlated well with lactase mRNA levels, indicating transcriptional control; it did less so with steady-state lactase activity. Examination of lactase mRNA levels and lactase activity/lactase mRNA ratios revealed a heterogeneous pattern of lactase mRNA level, lactase synthesis, and activity in both lactase persistent and hypolactasic subjects. CONCLUSIONS: Both transcriptional and posttranscriptional factors cause the decline of intestinal lactase. This probably explains the multifarious observations that most studies on adult-type hypolactasia have reported. The single overriding factor distinguishing lactase-persistent subjects from hypolactasic subjects is the high rate of lactase biosynthesis.