Loss of gallbladder interstitial Cajal-like cells in patients with cholelithiasis

Interstitial cells of Cajal (ICCs) play an important role in the regulation of gut motility. There is growing evidence that interstitial Cajal-like cells (ICLCs) are present in the gallbladder wall. We hypothesize that changes in the density of ICLCs in the gallbladder wall may lead to the development of cholelithiasis due to the impairment of the gallbladder motility. The purpose of this study was to identify ICLCs in the gallbladders of patients with gallstones and to assess their densities.

Data from 30 patients with gallstones and 25 individuals without gallstones were compared. Tissue samples were obtained during surgery, embedded in paraffin, and cut into sections. Following staining for CD117 and mast cell tryptase, the number of ICLCs and mast cells was determined using image analysis.

Cells positive for the c-Kit receptor (CD117) were detected in the gallbladder wall in all cases examined. Interstitial Cajal-like cells were most frequently observed in the muscularis propria. The density of ICLCs in the muscularis propria was significantly lower in the patients with gallstones than the density observed in the controls (26.24 ± 10.89 vs 56.29 ± 13.35 cells/mm(2)). In contrast, the number of mast cells in the gallbladder was increased in the patients with gallstones when compared with the controls (143 ± 24 vs 112 ± 19 cells/mm(2)).

The histopathological differences observed in this study may help elucidate the pathophysiology of gallstones. Gallbladder motility may be affected by the decreased number of ICLCs in patients with cholelithiasis.