Effects of a Gliadin Digest on RAW 264.7 Macrophages as a Model for Celiac Disease

Celiac disease causes disruption in the intestinal mucosa when exposed to gliadin-containing grains. The immune system’s response to gliadin is an intricate molecular signaling cascade involving the adaptive and innate immune systems. A majority of research in this area focuses upon the adaptive immune system, however, recent work suggests the innate immune system plays a significant role. Macrophages are innate immune system cells that work to protect a host organism from infection. RAW 264.7 Murine macrophages serve as a model for inflammatory responses by producing nitric oxide in response to an inflammatory stimulus. Experiments determined the level of macrophage activation from pepsin-trypsin digested gliadin (PT-gliadin) and undigested gliadin in comparison to an untreated control and a known stimulant, bacterial Lipopolysaccharide. Concentrations of PT-gliadin showed evidence of a dose response effect with 100 ug/mL, inducing a moderate stimulus and 500 and 1000 ug/mL stimulating a higher level of response. No significant differences were found between macrophage activation when exposed to 1000 ug/mL PT- gliadin and undigested gliadin. Determining the ability of gliadin to stimulate the RAW 264.7 macrophages will allow for investigation of potential roles for macrophages in the inflammatory process induced by gliadin.