TARDBP and inclusion body myositis: Interestingly, LC3, p62 and TDP-43 immunopositivities were not uniformly high in muscle biopsies from the 4 subjects with classic IBM history; rather, they showed a large range of labeling that spanned the entire spectrum of %FS values seen in the IBM group, with 3 of 4 subjects meeting or exceeding the 100% specificity threshold set for each of the three markers (Figures 2a, 2c, and 2e).