[ELISA-based determination of natural antibodies to endothelial NO-synthase in human blood and tear].

Research of natural antibodies (NAA) is a new trend in immunohistochemistry. NAA shape up, in biological fluids, as normal human endogenous low- and high-weight substances, e.g. angiotensin 2, bradykinin and others, and play the regulatory role in homeostasis. Endothelial NO-synthase (e-NOS) is a key enzyme in the path of NO shaping. An e-NOS alteration is important in the pathogenesis of diabetic microangiopathy including retinopathy. We determined, within our case study, the level of NAA to e-NOS in blood and tears of patients with diabetic retinopathy and in donors. The level of NAA to e-NOS was found to be twice higher in tears versus blood in all groups of patients. It depended on specific features and complications of diabetes mellitus.