Michael Behnke, BSc, PhD, assistant professor in the Department of Pathobiological Sciences (PBS) at the LSU School of Veterinary Medicine (LSU SVM), has recently been awarded a National Institute of Health (NIH) R21 grant for his project, entitled “Large farm and small companion animal intestinal organoids as platforms for parasite enteric development.” The award is for $407,000 for two years.

A cow enteroid, "mini-gut", grown in tissue culture. The mini-guts are seeded in a 3D matrix with media containing growth factors that induce the propagation of crypt stem cells. This enteroid has been stained to show cell membranes (green) and regions of active growth (pink). Image/ LSU School of Veterinary Medicine
A cow enteroid, “mini-gut”, grown in tissue culture. The mini-guts are seeded in a 3D matrix with media containing growth factors that induce the propagation of crypt stem cells. This enteroid has been stained to show cell membranes (green) and regions of active growth (pink).
Image/ LSU School of Veterinary Medicine

Dr. Behnke’s research study focuses on the parasites Toxoplasma gondii and Cryptosporidium parvum that can infect and cause disease in humans. Presently, there are no robust cell culture platforms for studying the gastrointestinal (enteric) stages of these parasites, in large part because techniques to grow intestinal epithelial cells in the lab have been lacking.

“This grant is key to allowing us to continue the work we have started here at the LSU School of Veterinary Medicine,” said Dr. Behnke. “It will help us to understand more about how medically relevant parasites establish infections and develop in the intestine.”

Recently, methods have been developed within the research community to continuously grow intestinal crypt organoids (enteroids) from human and mouse tissue. Dr. Behnke has adapted this technology to isolate and grow enteroids from various large farm and small companion (LF/SC) animals that serve as definitive hosts for parasites. These “mini-guts” have expanded over time and have been propagated to high passage number. The LF/SC enteroids will be characterized for the presence of Lgr5+ crypt cells and other intestinal cell linages, and will be used to develop a 2D growth platform for use in parasite infection and differentiation assays. The ability to grow and maintain LF/SC enteroid cell lines in tissue culture provides additional models for the study of gastrointestinal developmental biology as well as platforms for the study of host-pathogen interactions between intestinal cells and zoonotic pathogens of medical importance.

Project Summary

The parasites Toxoplasma gondii and Cryptosporidium parvum can infect and cause disease in humans, each with specific pathogenesis etiologies. Currently, there are no in vitro platforms for studying the enteric stages of these parasites, in large part because robust methods to expand intestinal epithelial cells from animals that are definitive hosts for these parasites have been lacking. Recently, methods were developed to continuously grow intestinal crypt organoids from human and mouse tissue. We have adapted these methods to isolate and grow intestinal crypt organoids from various large farm and small companion animals that serve as definitive hosts for parasites. These cell lines have expanded over time and have been propagated to high passage number. We intend to characterize these lines for the presence of Lgr5+ crypt cells and other intestinal cell linages, and to develop a 2D growth platform for use in parasite infection and differentiation assays.