Assessment of murine gut dysbiosis with intraluminal fluorescence lifetime imaging

Gastrointestinal disorders such as colorectal cancer or inflammatory bowel disease are linked to gut dysbiosis, an unbalanced gut microbiota. This early manifestation of the disease alters colon epithelial metabolism influencing the gut autofluorescence emission, which is susceptible to carry diagnostic value. We analyzed the fluorescence properties of healthy and dysbiotic ex vivo murine colons with an intraluminal fiber-based fluorescence lifetime imaging (FLIm) instrument. The results indicate that fluorescence lifetime reacts to inflammation in a spectrally dependant manner, and the full-length colon images allow to localize specific areas of activity. Imaging results were correlated to biochemical metabolic readouts (i.e. intracellular NADH, lactate) to establish the diagnostic potential of intraluminal FLIm.