Knockout of the Amino Acid Transporter SLC6A19 and Autoimmune Diabetes Incidence in Female Non-Obese Diabetic (NOD) Mice

Abstract

High protein feeding has been shown to accelerate the development of type 1 diabetes in female non-obese diabetic (NOD) mice. Here, we investigated whether reducing systemic amino acid availability via knockout of the <i>Slc6a19</i> gene encoding the system B(0) neutral amino acid transporter AT1 would reduce the incidence or delay the onset of type 1 diabetes in female NOD mice. <i>Slc6a19</i> gene deficient NOD mice were generated using the CRISPR-Cas9 system which resulted in marked aminoaciduria. The incidence of diabetes by week 30 was 59.5% (22/37) and 69.0% (20/29) in NOD.<i>Slc6a19^+/+</i> and NOD.<i>Slc6a19^-/-</i> mice, respectively (hazard ratio 0.77, 95% confidence interval 0.41-1.42; Mantel-Cox log rank test: <i>p</i> = 0.37). The median survival time without diabetes was 28 and 25 weeks for NOD.<i>Slc6a19^+/+</i> and NOD.<i>Slc6a19^-/-</i> mice, respectively (ratio 1.1, 95% confidence interval 0.6-2.0). Histological analysis did not show differences in islet number or the degree of insulitis between wild type and Slc6a19 deficient NOD mice. We conclude that Slc6a19 deficiency does not prevent or delay the development of type 1 diabetes in female NOD mice.