Although our initial results indicate that HPSE2 inhibits HPSE1 activity and prevents decline of renal function by competitively binding to HS, modelling of HPSE2 and mutation studies could further detail the mechanism of HPSE1 activity inhibition by HPSE2, which might ultimately contribute to better treatment options for patients who suffer from glomerular diseases. Here, HPSE is linked to glomerular disorder.