Immunoprecipitation of key WT1 isoforms with C-19 antibody although not with handle non-immune IgG was verified. On the other hand,PLOS One | DOI:ten.1371/journal.pone.0130578 June 19,10 /Novel WT1 Spliced IsoformEx4a(+)WT1 isoform was not co-precipitated with major WT1 isoform utilizing C-19 antibody (Figure B in S2 Fig). For that reason, it appeared that Ex4a(+)WT1 isoform did not physically ass