HPSE and glomerulonephritis: In our study, HPSE2 expression was downregulated in anti-GBM and LPS-induced glomerulonephritis, streptozotocin-induced DN, and adriamycin nephropathy, whereas this effect on HPSE2 expression was absent upon treatment with the HPSE1 inhibitor SST001 and in HPSE1-deficient mice.