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Boren, T.

Publications and source records attributed to Boren, T..

3 recordsLinked to original sources

Patient-derived organoids to study glycosylation dynamics during gastric disease

BACKGROUND AND AIMSAberrant cellular glycosylation remains a key event that accompanies and actively sustains gastric neoplastic transformation. Patient-derived organoids (PDOs) have recently emerged as a promising ex vivo model to study human gastric disorders. Since the PDOs glycosylation landscape remains unknown, this study aims to evaluate PDOs as potential avatars of in vivo tissue glycosylation profiles in the gastric context. METHODSFresh gastric mucosa samples derived from non-tumoral obese patients (n=11), adjacent tumor mucosa samples (n=29), and tumor tissue samples derived from gastric cancer (GC) patients (n=30) were used to establish a biobank of gastric PDOs (n=56). The N- and O-glycophenotypes of normal, adjacent, and tumor PDOs and respective in vivo tissues were thoroughly characterized by immunostaining. Additionally, a comparative glycan analysis was performed over time, upon PDO biobanking and xenografting in mice. The binding of two Helicobacter pylori (H. pylori) isogenic strains with distinct glycan-binding affinities was assessed in parental gastric mucosa tissues and compared with the respective PDOs before and after modulation of their glycan landscape. RESULTSOur results show that PDOs mimic different phenotypes of the carcinogenic cascade and recapitulate parental gastric tissues glycosylation profile. Tumor PDOs recapitulate the inter- and intra-heterogeneity features observed in GC, which is maintained over time, upon biobanking and xenografting. We demonstrated that the expression of type I and type II Lewis antigens is dynamically controlled by PDOs differentiation status, which results in differential binding to H. pylori strains displaying distinct glycan-binding adhesins, mirroring the gastric epithelium tissue interactions. CONCLUSIONSThis study established PDOs as invaluable ex vivo tools to study the complex glycan dynamics in both gastric physiological and pathological settings.

cell biology↗

Vaccination with Helicobacter pylori attachment proteins protects against gastric cancer

Most cases of gastric cancer are caused by chronic Helicobacter pylori infection, but the lack of early onco-diagnostics and a high risk for antibiotic resistance hampers early intervention through eradication of H. pylori infection by antibiotics. We reported on a protective mechanism where H. pylori gastric mucosal attachment can be reduced by natural antibodies that block the binding of its attachment protein BabA. Here we show that challenge infection with H. pylori induced response of such blocking antibodies in both human volunteers and in rhesus macaques, that mucosal vaccination with BabA protein antigen induced blocking antibodies in rhesus macaques, and that vaccination in a mouse model induced blocking antibodies that reduced gastric mucosal inflammation, preserved the gastric juice acidity, and fully protected the mice from gastric cancer caused by H. pylori.

immunology↗

Helicobacter pylori attachment-blocking antibodies protect against duodenal ulcer disease

The majority of the world population carry the gastric pathogen Helicobacter pylori. Fortunately, most individuals experience only low-grade or no symptoms, but in many cases the chronic inflammatory infection develops into severe gastric disease, including duodenal ulcer disease and gastric cancer. Here we report on a protective mechanism where H. pylori attachment and accompanying chronic mucosal inflammation can be reduced by antibodies that are present in a vast majority of H. pylori carriers. These antibodies block binding of the H. pylori attachment protein BabA by mimicking BabAs binding to the ABO blood group glycans in the gastric mucosa. However, many individuals demonstrate low titers of BabA blocking antibodies, which is associated with an increased risk for duodenal ulceration, suggesting a role for these antibodies in preventing gastric disease.

immunology↗