Figure 1.

Discovery, screening, and validation cohorts of PCDH7-positive MN. (A) In the discovery cohort, MS/MS was performed in 135 cases to look for novel proteins in PLA2R-negative MN. Eight cases were positive for a unique protein PCDH7. IHC for PCDH7 was performed on the eight cases and showed granular GBM staining for PCDH7. In the screening cohort, we performed IHC on 40 cases of PLA2R-negative MN and found two cases of PCDH7-positive MN. The findings were confirmed by MS/MS in both cases. (B) In the validation cohorts, IF for PCDH7 was performed in two cohorts. No positive cases were detected in the French cohort of 31 cases, whereas four positive cases were detected in the Belgian cohort of 38 cases.