Wang et al. reported that PMSCs could be recruited into immune organs to promote Th17/Treg balance in the kidneys and blood of DKD rats by acting on the PD-1/PD-L1 pathway, which reduced the levels of proinflammatory cytokines (IL-17A and IL-1β) and improved renal function and pathological damage in DKD rats [120]. Here, IL17A is linked to diabetic kidney disease.