GRANTS. Two young researchers at Sahlgrenska Academy have received approval for their grant application to the National Institutes of Health (NIH) Mucosal Immunology Science Team (MIST). It’s a prestigious appropriation because the NIH provides funds to non-U.S. scientists only in exceptional cases.
George Birchenough and Thaher Pelaseyed are both postdoctoral research fellows at the Department of Medical Chemistry and Cell Biology. Each of them is working on his own research track, which in different ways examines how the human intestine is protected against bacterial infection.
Strengthening the hypothesis
George Birchenough will receive a total of SEK 1.3 million for his project. He and his colleagues recently described a new subtype of cells in the large intestine surface layer, and their hypothesis is that this type of goblet cells acts as the intestine’s last line of defense against bacteria. They believe that these sentinel cells detect and flush away bacteria when the normal protective mucous barrier has given way. In collaboration with Gunnar C. Hansson and Fredrik Bäckhed, George Birchenough will now try to validate the evidence that these newly discovered cells really have the function previously described.
In another study published in Cell Host & Microbe last year, researchers showed that the protective mucous barrier in the large intestine was destroyed in mice receiving a Western diet high in fat and low in fiber.
“The idea is that I will use a Western diet to cause mucous barrier failure in mice and study whether the newly discovered sentinel cells are activated as we expect,” George says.
“My plan is to conduct the same experiments in transgenic mice in which these cells are not active. If the sentinel cells are activated after the mucous barrier is damaged and if the transgenic mice become sicker than the mice where the sentinel cells can do their job, then we have really good evidence that the sentinel cells we discovered are important in the intestinal defense system.
Interactions between bacteria and cells
Thaher Pelaseyed will receive almost SEK 750,000 from the NIH for his project. Thaher and his research team have shown that a certain type of glycoprotein on the surface of intestinal cells, a transmembrane mucin, acts as a sensor that detects the intestine’s bacteria.
“Interestingly, some bacteria promote intestinal cells to produce more of the sensor, which points to an interplay between the microbiota and intestinal cells,” Thaher comments.
With the help of the grant from NIH/MIST, Thaher’s research team will now investigate which intestinal bacteria the sensor recognizes and how their favorite protein protects the intestinal cells against encroaching bacteria.
TEXT AND PHOTO: ELIN LINDSTRÖM CLAESSEN