NPHS1 and focal segmental glomerulosclerosis: This factor, or factors may be an auto-antibody: in a recent study, 29% patients with MCD had anti-nephrin antibodies in the serum at the time of nephrosis, and on renal biopsy, IgG co-localised with nephrin [8] Anti-nephrin antibodies have also been reported in patients with recurrent FSGS [9].