Our findings demonstrated that Pdpn+ macrophages, rather than Pdpn− macrophages, ameliorated vascular injury in T2DM in an adipocyte-dependent manner, suggesting that Pdpn might play a key role in the vasoprotective effects of Pdpn+ macrophages by alleviating insulin resistance in adipocytes. Here, PDPN is linked to type 2 diabetes mellitus.