Crohn disease and ulcerative colitis are two subphenotypes of inflammatory bowel disease (IBD), a complex disorder resulting from gene-environment interaction. We refined our previously defined linkage region for IBD on chromosome 10q23 and used positional cloning to identify genetic variants in DLG5 associated with IBD. DLG5 encodes a scaffolding protein involved in the maintenance of epithelial integrity. We identified two distinct haplotypes with a replicable distortion in transmission (P = 0.000023 and P = 0.004 for association with IBD, P = 0.00012 and P = 0.04 for association with Crohn disease). One of the riskassociated DLG5 haplotypes is distinguished from the common haplotype by a nonsynonymous single-nucleotide polymorphism 113G→A, resulting in the amino acid substitution R30Q in the DUF622 domain of DLG5. This mutation probably impedes scaffolding of DLG5. We stratified the study sample according to the presence of risk-associated CARD15 variants to study potential gene-gene interaction. We found a significant difference in association of the 113A DLG5 variant with Crohn disease in affected individuals carrying the risk-associated CARD15 alleles versus those carrying non-risk-associated CARD15 alleles. This is suggestive of a complex pattern of genegene interaction between DLG5 and CARD15, reflecting the complex nature of polygenic diseases. Further functional studies will evaluate the biological significance of DLG5 variants. D10S201 D10S213 cM

A comparison of oligonucleotide and cDNA-based microarray systems. Physiol Genomics 16: 361-370, 2004. First published November 25, 2003 10.1152/physiolgenomics.00080.2003.-Large-scale public data mining will become more common as public release of microarray data sets becomes a corequisite for publication. Therefore, there is an urgent need to clarify whether data from different microarray platforms are comparable. To assess the compatibility of microarray data, results were compared from the two main types of high-throughput microarray expression technologies, namely, an oligonucleotide-based and a cDNA-based platform, using RNA obtained from complex tissue (human colonic mucosa) of five individuals. From 715 sequence-verified genes represented on both platforms, 64% of the genes matched in "present" or "absent" calls made by both platforms. Calls were influenced by spurious signals caused by Alu repeats in cDNA clones, clone annotation errors, or matched probes that were designed to different regions of the gene; however, these factors could not completely account for the level of call discordance observed. Expression levels in sequence-verified, platform-overlapping genes were not related, as demonstrated by weakly positive rank order correlation. This study demonstrates that there is only moderate overlap in the results from the two array systems. This fact should be carefully considered when performing large-scale analyses on data originating from different microarray platforms. noncommercial clone-based microarray system; commercial oligonucleotide-based microarray system; expression screening platform; cross-platform screening

Gaucher disease (GD), an autosomal recessive lipid storage disorder, arises from mutations in the GBA1 (β-glucocerebrosidase) gene, resulting in glucosylceramide accumulation in tissue macrophages. Lyso-Gb1 (glucosylsphingosine, lyso-GL1), a downstream metabolic product of glucosylceramide, has been identified as a promising biomarker for the diagnosis and monitoring of patients with GD. This retrospective, exploratory analysis of data from phase 3 clinical trials of velaglucerase alfa in patients with type 1 GD evaluated the potential of lyso-Gb1 as a specific and sensitive biomarker for GD. A total of 22 treatment-naïve patients and 21 patients previously treated with imiglucerase (switch patients) were included in the analysis. Overall, demographics between the two groups were similar. Mean lyso-Gb1 concentrations were reduced by 302.2ng/mL from baseline to week 209 in treatment-naïve patients and by 57.3ng/mL from baseline to week 161 in switch patients, corresponding to relative reductions of 82.7% and 52.0%, respectively. In both the treatment-naïve and switch groups, baseline mean lyso-Gb1 was higher for patients with at least one N370S mutation (363.9ng/mL and 90.7ng/mL, respectively) than for patients with non-N370S mutations (184.6ng/mL and 28.3ng/mL, respectively). Moderate correlations between decreasing lyso-Gb1 levels and increasing platelet counts, and with decreasing spleen volumes, were observed at some time points in the treatment-naïve group but not in the switch group. These findings support the utility of lyso-Gb1 as a sensitive and reliable biomarker for GD, and suggest that quantitation of this biomarker could serve as an indicator of disease burden and response to treatment.

A relationship between the structure of 21 2-[[(2-pyridyl)methyl]thio]-1H-benzimidazoles (6) and their anti Helicobacter pylori activity expressed as minimum bactericidal concentration (MBC) values is described. Observed MBCs ranged from 256 to 1 microg/mL. The structure-activity relationship (SAR) showed that larger and more lipophilic compounds, especially compounds with such substituents in the 4-position of the pyridyl moiety, generally had lower MBC values. Four new compounds that were predicted to be potent by the established SAR model were synthesized and tested. One such compound, i.e., 2-[[(4-[(cyclopropylmethyl)oxy]-3-methyl-2-pyridyl)methyl]thio]-1H-be nzimidazole (18), was tested for in vivo efficacy in a mouse Helicobacter felismodel (125 micromol/kg bid given orally for 4 days, n = 4). Unfortunately, antibacterial activity could not be clearly demonstrated in this model. Instead a potent acid secretion inhibition was observed. This finding was attributed to the methylthio compound being oxidized to the corresponding methyl sulfinyl derivative, i.e., a proton pump inhibitor, in vivo. Although the antibacterial activity had the potential of decreasing H. felis cell counts in vivo the proton pump inhibitory effect became dominant and actually promoted H. felis cell growth. Hence, we conclude that the antibacterial utility of the 2-[[(2-pyridyl)methyl]thio]-1H-benzimidazoles (6) as a compound class is compromised by their propensity to become proton pump inhibitors upon metabolic oxidation in vivo.

International guidelines conditionally recommend long-term prophylaxis in patients with von Willebrand disease (VWD) and severe/frequent bleeding. As recombinant von Willebrand factor (rVWF, vonicog alfa) may reduce the frequency of treated spontaneous bleeding events (BEs), we investigated the efficacy and safety of rVWF prophylaxis in adults with severe VWD. Patients with BEs requiring VWF therapy in the past year (on-demand VWF therapy [Prior On-Demand group] or plasma-derived VWF prophylaxis [pdVWF; Switch group]) were enrolled in a prospective, open-label, nonrandomized, phase 3 study. Planned duration of rVWF prophylaxis was 12 months; starting rVWF dose was 50±10 VWF:RCo IU/kg twice weekly (Prior On-Demand group) or based on prior pdVWF weekly dose/dosing frequency (Switch group). The primary endpoint was annualized bleeding rate of treated spontaneous BEs (sABR) during rVWF prophylaxis. Over the 12-month study period, treated sABR decreased by 91.5% on-study versus historical sABR in 13 patients in Prior On-Demand group, and by 45.0% in 10 patients in Switch group (model-based analysis ratio [95% CI]: 0.085 [0.021-0.346] and 0.550 [0.086-3.523], respectively). No treated spontaneous BEs were recorded in 84.6% (11/13) and 70.0% (7/10) of patients, respectively. The safety profile of rVWF was consistent with the previously established profile, with no new adverse drug reactions identified. Findings suggest that rVWF prophylaxis can reduce treated spontaneous BEs in patients previously receiving on-demand VWF therapy and maintains at least the same level of hemostatic control in patients who switch from prophylaxis with pdVWF to rVWF, with a favorable safety profile. Trial registration: www.clinicaltrials.gov (#NCT02973087) and www.clinicaltrialsregister.eu (#EudraCT 2016-001478-14).