Journal: Biomolecules

Article Title: Complement Activation May Drive the Pathogenicity of Anti-α6 and Anti-β4 Integrin Antibodies In Vivo

doi: 10.3390/biom16030417

Figure Lengend Snippet: Anti-α6 and anti-β4 integrin IgG fail to fix complement along the BMZ in vitro. Representative indirect immunofluorescence microscopy images of murine buccal mucosa, conjunctiva, and skin biopsies are shown. Following incubation of sections with IgG, fresh hirudin plasma was added as a complement source. Complement activation was assessed using anti-C3 staining. Robust linear C3 deposition (arrows) along the BMZ was observed in normal murine skin treated with IgG against the recombinant NC1 domain of collagen type VII (anti-COL7 IgG, positive control). In contrast, no C3 deposition was detected in tissues treated with anti-α6 integrin IgG or anti-β4 integrin IgG, indicating their inability to activate complement in vitro. Sections incubated with normal rabbit (NR) IgG (negative control) served as negative controls. Nuclei were counterstained with DAPI (blue). Scale bars, 100 μm.

Article Snippet: Subsequently, the sections were stained with FITC-conjugated anti-human complement C3 IgG (dilution 1:100; MP Biomedicals, Eschwege, Germany) for 1 h at 37 °C.

Techniques: In Vitro, Immunofluorescence, Microscopy, Incubation, Clinical Proteomics, Activation Assay, Staining, Recombinant, Positive Control, Negative Control