Van Rheenen publication in Gastroenterology

Today, Hugo Snippert (UMCU) and the Van Rheenen group published their paper “In vivo Imaging Reveals Existence of Crypt Fission and Fusion in Adult Mouse Intestine” in Gastroenterology. In this study, they used intravital microscopy to uncover crypt fusion for the first time – a mechanism that can counteract the continuous birth of new crypts via the already known process of crypt fission. The first author of the paper is Lotte Bruens. 

The intestinal epithelium is a repetitive sheet of crypt and villus units with stem cells at the bottom of the crypts. During postnatal development, crypts multiply via fission, generating two daughter crypts from one parental crypt. In this paper, the crypt fission was observed at a low frequency in the adult intestine of mice. To do this they used intravital microscopy in “Lgr5EGFP-Ires-CreERT2 mice”, which are mice with their stem cells labeled in green.

Fig 1: fusion and fission of crypts observed with in vivo imaging

The researchers monitored the individual crypt dynamics over multiple days with single-cell resolution, using advanced single cell techniques. They discovered the existence of crypt fusion, which is an almost exact reverse phenomenon of crypt fission – in which two crypts fuse into one daughter crypt. Examining 819 crypts in four mice, they found that 3.5%±0.6% of all crypts were in the process of fission, whereas 4.1±0.9% of all crypts were undergoing crypt fusion. Additionally, as a counteracting processes, crypt fission and fusion could regulate crypt numbers during the lifetime of a mouse.

Identifying the mechanisms that regulate rates of crypt fission and fusion could provide insights into intestinal adaptation to altered environmental conditions and disease pathogenesis, such as colorectal cancer.

Read more about it at the lab page of Hugo Snippert of the UMCU.

Read the whole paper here.