Binding of sHSPs to the elastic I-bands in human dystrophic skeletal muscle. (A and B) Representative immunofluorescence images of sectioned muscle biopsies comparing tissue from healthy subjects with that from LGMD2A patients. (A) Immunostaining for endogenous HSP27 (secondary antibody: FITC-conjugated IgG; left) and counterstaining for PEVK titin (secondary antibody: Cy3-conjugated IgG; middle). (B) Immunostaining for endogenous αB-crystallin (secondary antibody: Cy3-conjugated IgG; left) and counterstaining for PEVK titin (secondary antibody: FITC-conjugated IgG; middle). Right panels show merged images. (insets) Higher-power images of sections differing from those shown in the respective main panels. Bars, 5 µm. (C) Relative I-band positions of endogenous sHSPs and PEVK at different SLs in myocytes from LGMD2A patients (left). Each data point represents an epitope–epitope (E-E) distance value measured across the Z-disk. Regression curves are of order 2. The right panel illustrates the range of sHSP binding locations on titin.