TY  - JOUR
A1  - Trujillo‐Viera, Jonathan
A1  - El‐Merahbi, Rabih
A1  - Schmidt, Vanessa
A1  - Karwen, Till
A1  - Loza‐Valdes, Angel
A1  - Strohmeyer, Akim
A1  - Reuter, Saskia
A1  - Noh, Minhee
A1  - Wit, Magdalena
A1  - Hawro, Izabela
A1  - Mocek, Sabine
A1  - Fey, Christina
A1  - Mayer, Alexander E.
A1  - Löffler, Mona C.
A1  - Wilhelmi, Ilka
A1  - Metzger, Marco
A1  - Ishikawa, Eri
A1  - Yamasaki, Sho
A1  - Rau, Monika
A1  - Geier, Andreas
A1  - Hankir, Mohammed
A1  - Seyfried, Florian
A1  - Klingenspor, Martin
A1  - Sumara, Grzegorz
T1  - Protein Kinase D2 drives chylomicron‐mediated lipid transport in the intestine and promotes obesity
JF  - EMBO Molecular Medicine
N2  - Lipids are the most energy‐dense components of the diet, and their overconsumption promotes obesity and diabetes. Dietary fat content has been linked to the lipid processing activity by the intestine and its overall capacity to absorb triglycerides (TG). However, the signaling cascades driving intestinal lipid absorption in response to elevated dietary fat are largely unknown. Here, we describe an unexpected role of the protein kinase D2 (PKD2) in lipid homeostasis. We demonstrate that PKD2 activity promotes chylomicron‐mediated TG transfer in enterocytes. PKD2 increases chylomicron size to enhance the TG secretion on the basolateral side of the mouse and human enterocytes, which is associated with decreased abundance of APOA4. PKD2 activation in intestine also correlates positively with circulating TG in obese human patients. Importantly, deletion, inactivation, or inhibition of PKD2 ameliorates high‐fat diet‐induced obesity and diabetes and improves gut microbiota profile in mice. Taken together, our findings suggest that PKD2 represents a key signaling node promoting dietary fat absorption and may serve as an attractive target for the treatment of obesity.
KW  - chylomicron
KW  - fat absorption
KW  - intestine
KW  - obesity
KW  - protein kinase D2/PKD2/PRKD2
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239018
VL  - 13
IS  - 5
ER  - 
TY  - JOUR
A1  - Wallaschek, Nina
A1  - Reuter, Saskia
A1  - Silkenat, Sabrina
A1  - Wolf, Katharina
A1  - Niklas, Carolin
A1  - Özge, Kayisoglu
A1  - Aguilar, Carmen
A1  - Wiegering, Armin
A1  - Germer, Christoph-Thomas
A1  - Kircher, Stefan
A1  - Rosenwald, Andreas
A1  - Shannon-Lowe, Claire
A1  - Bartfeld, Sina
T1  - Ephrin receptor A2, the epithelial receptor for Epstein-Barr virus entry, is not available for efficient infection in human gastric organoids
JF  - PLoS Pathogens
N2  - Epstein-Barr virus (EBV) is best known for infection of B cells, in which it usually establishes an asymptomatic lifelong infection, but is also associated with the development of multiple B cell lymphomas. EBV also infects epithelial cells and is associated with all cases of undifferentiated nasopharyngeal carcinoma (NPC). EBV is etiologically linked with at least 8% of gastric cancer (EBVaGC) that comprises a genetically and epigenetically distinct subset of GC. Although we have a very good understanding of B cell entry and lymphomagenesis, the sequence of events leading to EBVaGC remains poorly understood. Recently, ephrin receptor A2 (EPHA2) was proposed as the epithelial cell receptor on human cancer cell lines. Although we confirm some of these results, we demonstrate that EBV does not infect healthy adult stem cell-derived gastric organoids. In matched pairs of normal and cancer-derived organoids from the same patient, EBV only reproducibly infected the cancer organoids. While there was no clear pattern of differential expression between normal and cancer organoids for EPHA2 at the RNA and protein level, the subcellular location of the protein differed markedly. Confocal microscopy showed EPHA2 localization at the cell-cell junctions in primary cells, but not in cancer cell lines. Furthermore, histologic analysis of patient tissue revealed the absence of EBV in healthy epithelium and presence of EBV in epithelial cells from inflamed tissue. These data suggest that the EPHA2 receptor is not accessible to EBV on healthy gastric epithelial cells with intact cell-cell contacts, but either this or another, yet to be identified receptor may become accessible following cellular changes induced by inflammation or transformation, rendering changes in the cellular architecture an essential prerequisite to EBV infection.
KW  - Organoids
KW  - ephitelial cells
KW  - gastrointestinal infections
KW  - cancers and neoplasms
KW  - Epstein-Barr virus
KW  - flow cytometry
KW  - epithelium
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259206
VL  - 17
IS  - 2
ER  -