Fig. 1

Immunohistochemical staining of glomerular IgG subclasses and PLA2R distribution (× 400). a–e are IgG1, IgG2, IgG3, IgG4 and PLA2R staining on the renal sections of a patient with mercury-associated MN, and the corresponding semi-quantitative scores are 2, 1, 0, 2 and 0, respectively. f–j are positive controls. f, i and j are IgG1, IgG4 and PLA2R staining on the renal sections of a patient with I-MN, and the corresponding semi-quantitative scores are 3, 2 and 3. g and h are IgG2 and IgG3 staining on the renal sections of a patient with systemic lupus erythematosus, and the corresponding semi-quantitative scores are 2 and 2