Neopterin level can be measured by intraocular liquid biopsy

Robust intraocular markers are needed in clinical practice for several inflammatory ophthalmological conditions in addition to advanced imaging, histology and immunohistochemistry tests in order to assure reliable diagnosis. Neopterin (NPt) is produced by activated lymphocyte T cells and is known to increase within the CNS in proinflammatory or early infectious states. This study aimed to measure intraocular NPt in aqueous liquid following intraocular liquid biopsy using standard methods. We enrolled 20 healthy patients without known inflammatory history or medication underdoing cataract surgery and analyzed samples for 19 out of 20. NPt level was measured below 1,9 nmol/l in 16 patients (84 %) and less than 3 nmol/l in 94,74%. Given the first time that NPt is measured in intraocular liquids we compared with the established reference limits within the CSF. These findings suggest that NPt could serve as a potential additional signature in ophthalmological conditions to differentiate between any or proinflammatory intraocular state, as well in follow-up.