They first tested the effect on normal adipocytes incubated with plasma from patients with type 1 diabetes versus controls, and noted higher rates of release of CCL2, TNF-α, adiponectin, as well as upward trends for RBP-4 and cathepsin S. In contrast, high glucose levels alone increased CCL2 secretion and lowered adiponectin and RBP4 by adipocytes, without any changes in cathepsin S, chemerin, leptin, or PAI-1. Here, RBP4 is linked to type 1 diabetes mellitus.