Objective To generate and identify the Itgbl1(integrin beta-like)promoter-driven Cre knock-in mouse line.Methods Itgbll-Cre knock-in mice were generated using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing.The Itgbl1-Cre mice were crossed with the Cre reporter ROSALSL-tdTomato)mice to detect the expression profile of Cre activity.The tdTomato expression pattern across tissues and cell-specific markers were used to identify the cell types of Itgbl1-expressing cells and their progeny.Results and Conclusion tdTomato was specifically expressed in mucous acinar cells of the sublingual gland,pancreatic islet cells,and gastric endocrine cells.In addition,tdTomato expression was also found in some of the neurons of the retina and brain,as well as in a few cells in the serosal layer of the intestine,articular cartilage,periosteum,and bone marrow.The first Itgbl1-Cre recombinase transgenic mouse line was established,which can specifically label the mucous acinar cells of the sublingual gland.

Somatostatin (SST) is an inhibitory polypeptide hormone that plays an important role in a variety of biological processes. Somatostatin receptor 2 (SSTR2) is the most widely expressed somatostatin receptor. However, the specific cell types expressing Sstr2 in the tissues have not been investigated. In this study, we detected the expression pattern of SSTR2 protein in mouse at different development stages, including the embryonic 15.5 days and the postnatal 1, 7, 15 days as well as 3 and 6 months, by multicolour immunofluorescence analyses. We found that Sstr2 was expressed in some specific cells types of several tissues, including the neuronal cells and astrocytes in the brain, the mesenchymal cells, the hematopoietic cells, the early hematopoietic stem cells, and the B cells in the bone marrow, the macrophages, the type Ⅱ alveolar epithelial cells, and the airway ciliated cells in the lung, the epithelial cells and the neuronal cells in the intestine, the hair follicle cells, the gastric epithelial cells, the hematopoietic stem cells and the nerve fibre in the spleen, and the tubular epithelial cells in the kidney. This study identified the specific cell types expressing Sstr2 in mouse at different developmental stages, providing new insights into the physiological function of SST and SSTR2 in several cell types.
Mice ; Animals ; Receptors, Somatostatin/metabolism* ; Hematopoietic Stem Cells/metabolism* ; Epithelial Cells