A key gene known as CSF1R has been found to be active in specialized epithelial cells found in the chicken gut, the Roslin Institute in Scotland announced.

The institute said the finding was "unexpected" since CSF1R is typically expressed not in epithelial cells, which line tissue surfaces in the body, but in macrophage cells, which detect and kill infection.

The results in studies with chicken cells pave the way for research looking to enhance the effectiveness of vaccines in chickens and at how pathogens invade the body, Roslin said.

According to the announcement, scientists at the Roslin Institute used transgenic reporter chickens — a method for visualizing gene expression — to observe the transport of particles and pathogens by specialized epithelial cells.

These bear similarities to M cells in mammals, which have the same function. The key difference is the expression of the CSF1R gene in chicken M cells, the institute said.

"The use of transgenic reporter chickens and imaging methods normally enables us to observe CSFR1 gene expression in macrophages, which detect and kill pathogens. We were surprised to find that this gene was also expressed in the chicken’s epithelium but quickly realized that this provided an excellent opportunity to study chicken M cells at a level of detail that has not been possible before," said Dr. Adam Balic with the Roslin Institute.

This discovery, published in the journal Frontiers in Immunology and funded by the U.K.'s Biotechnology & Biological Sciences Research Council, lays the foundation for studies using the CSF1R gene as a biological indicator of M cells to investigate infection and immunity in chickens.

Roslin Institute professor Lonneke Vervelde added, "We will continue to work on M cells to better understand how they develop in the young chick, whether they can be targeted to improve vaccine uptake and how they are abused by invading pathogens to infect chickens."