Fig. 1.

Workflow for measuring kinetic entries of plasma proteins into aqueous using ¹⁵N-labeled mouse serum as a tracer. (A) ¹⁵N-labeled serum was collected from donor mice that were metabolically labeled with ¹⁵N via SILAM. Then 300 μL of ¹⁵N-labeled serum was injected into the tail vein of ¹⁴N mice. Before receiving ¹⁵N serum, these subject mice had been prepared with one of the two eyes injured, and then allowed to recover for 2 wk. Aqueous from each eye and serum samples were collected following a time course. (B) The aqueous contents of ¹⁵N-labeled proteins were measured as ¹⁵N/¹⁴N ratios for individual proteins by LC-MS/MS.