Cnr2-flox Mouse

Cnr2, encoding cannabinoid receptor type 2 (CB2R), is mainly expressed by leukocytes and has a role in the immune system. It can modulate immune responses and is involved in various biological processes such as implantation, sensory information processing, and the regulation of anxiety and stress recovery. It is part of the endogenous cannabinoid system (ECS), which plays a role in many physiological functions [2,3,5].

Using a knock-in mouse model expressing a FLAG-tagged Cnr2 gene, researchers found that cannabinoids impair the function of tumor-specific T cells through Cnr2. Cnr2 binds to JAK1 and inhibits the downstream STAT signaling in T cells, suppressing antitumor immunity [1].

Cnr2-deficient mice show resistance to lipopolysaccharide (LPS)-driven preterm birth due to increased IL-10 production via augmented cAMP accumulation [4]. In addition, Cnr2-deficient mice have compromised implantation, with uterine epithelium abnormalities and blood vessel leakage during implantation [3].

In conclusion, Cnr2 is crucial for multiple biological functions. Its role in suppressing antitumor immunity through the JAK/STAT signaling pathway in T cells, as well as its functions in implantation and inflammation-induced preterm birth, are revealed by gene-knockout mouse models. Understanding Cnr2 functions helps to better comprehend related biological processes and may provide insights for treating relevant diseases [1,3,4].