Nerve Epidermal Growth Factor-Like 1 Protein (NELL-1) Expression in Mercury-Related Membranous Nephropathy: Is It a True Association or a Chance Occurrence?

Neural epidermal-like growth factor-like 1 (NELL-1) is a protein kinase C binding protein expressed in osteoblasts and renal tubules. It is expressed in 5%-25% glomerular cells at the mRNA level. Membranous Nephropathy (MN) is characterized by the presence of antibodies against certain types of antigens on the glomerular basement membrane. The most common one implicated in primary MN is an antibody against PLA2R. Many newer antigens have been discovered in the recent past, which are proven to cause secondary MN, one of which is NELL-1. NELL-1 has been associated with malignancy-associated MN and also recently associated with traditional indigenous medications containing mercury. In this study, we study the expression of NELL-1 in mercury-associated MN.