Kidney Injury Molecule 1 (Kim1), also known as HAVCR1, is a transmembrane glycoprotein that is undetectable in healthy kidneys but becomes dramatically upregulated on the apical membrane of proximal tubule cells following injury. It functions as a phosphatidylserine receptor, enabling injured tubular cells to phagocytose dead cells and debris, a process critical for limiting inflammation and promoting tissue repair. 
Besides,YY1 Transcription Factor (YY1) has been identified as an interactor of Kim1, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human Kim1 and recombinant human YY1. Briefly, Kim1 was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to YY1-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-Kim1 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 µL stop solution to the wells and read at 450/630nm immediately. The binding activity of recombinant human Kim1 and recombinant human YY1 was shown in Figure 1, the EC50 for this effect is 0.68 µg/mL.