March 26, 2019
Hokkaido University
Keio University
A research group, including Assistant Professor Shunsuke Kimura from the Department of Histology and Cell Biology, Graduate School of Medical Sciences at Hokkaido University, and Professor Koji Hase from the Faculty of Pharmacy at Keio University, has discovered that the acquisition of the antigen uptake function of "M cells," which are important for the immunity of the intestinal tract (a digestive organ divided into the small and large intestines), is controlled by the transcription factor Sox8.
The intestinal tract contains antigens from food and gut microbiota and can sometimes be a site of bacterial infection. Infants and young children, in particular, have underdeveloped immune systems and are susceptible to infectious diseases, making the development of the immune system during this period an important research topic. While infants can receive antibodies from breast milk, an "antibody gap" occurs during the weaning period when this supply ceases, necessitating the rapid establishment of their own immune system.
M cells are cells located in the epithelium lining the intestinal tract that take up antigens. For the immune system to be activated and produce antibodies, it is crucial for it to be exposed to antigens taken up by M cells. However, the mechanism by which M cells acquire this uptake function has remained largely unknown.
The research group found that Sox8, a transcription factor that controls gene expression, is present in M cells, and that mice lacking Sox8 have reduced M cell uptake capacity. Furthermore, in these Sox8-deficient mice, the ability to produce secretory IgA antibodies after weaning was significantly lower compared to normal mice. These results reveal that the efficient uptake of intestinal antigens by M cells is crucial for filling the antibody gap after weaning.
These research findings were published in the Journal of Experimental Medicine on March 15, 2019.
For the full press release, please see below.