Fig. 8. Disruption of basement membrane organization in SSPN-Tg muscle. Immunostaining of transverse quadriceps sections from non-Tg, non-phenotypic SSPN-Tg (line 31.6), and phenotypic SSPN-Tg (line 37.5) mice. Sections were co-stained with (A) monoclonal antibodies against perlecan (green) and collagen VI (red) or (B) antibodies against perlecan (green) and laminin (red). Merged images of green and red fluorescence are shown in the far right panel. In normal muscle (non-Tg and non-phenotypic SSPN-Tg), perlecan completely co-localizes with collagen VI (A) or laminin (B) at the basement membrane. In muscle from the phenotypic SSPN-Tg mice, collagen VI is present in the basement membrane but appears patchy and reduced in intensity relative to the perlecan and laminin. Collagen VI staining is increased in the interstitial and perivascular space (arrows). Collagen VI and laminin are not co-localized with perlecan in phenotypic SSPN-Tg mice, as demonstrated in merged images. Bar, 50 µm.