Src-kinase associated protein 2 (SKAP2) is an intracellular scaffolding protein broadly expressed in immune cells. It is involved in multiple downstream signalling pathways, especially integrin signalling, and plays a crucial role in fine-tuning cytoskeleton rearrangement, thereby regulating cell migration and immune cell function. Mutations in SKAP2 have been associated with inflammatory disorders like Type 1 Diabetes and Crohn's disease [1].

SKAP2-deficient immune cells in rodent studies showed diminished pathogen clearance due to impaired ROS production and/or phagocytosis [1]. In mice, Skap2 knockout increased the severity of colitis and tumorigenesis, as well as LPS-induced acute inflammation, indicating its role in suppressing inflammation-mediated tumorigenesis by regulating SHP-1 and SHP-2 [2]. Skap2-/-mice also had 100-fold higher bacterial burden in K. pneumoniae pulmonary infections, with abolished K. pneumoniae-stimulated ROS production in vitro in neutrophils, highlighting its importance in defence against this infection [3]. In newly diagnosed type 1 diabetes children, a single nucleotide polymorphism in SKAP2 predicted glycemic control and residual β-cell function, and knockdown of SKAP2 in INS-1E cells and primary rat β-cells aggravated cytokine-induced apoptosis [4].

In conclusion, SKAP2 is essential for functions such as immune cell-mediated pathogen clearance, suppression of inflammation-related tumorigenesis, defence against certain bacterial infections, and regulation of β-cell apoptosis in relation to type 1 diabetes. Gene knockout mouse models have been instrumental in revealing these roles, providing insights into the underlying mechanisms of these disease-related processes.