Figure 6. Specificity of anti-ATH on sections of chick ocular tissues. Fixed cryostat sections of chick sclera and choroid were incubated with A) monoclonal anti-ATH antibody (ATH positive), with B) anti-ATH antibody that was preincubated with 2 μM recombinant chick ATH (ATH protein block), or with C) nonimmune mouse IgG (IgG control) followed by incubation in anti-mouse IgG conjugated to AlexaFluor 568 (red). No specific immunoreactivity is observed in fibrous sclera (FS) and choroid when antibodies were preincubated with ATH, indicating the specificity of the anti-ATH antibodies for ATH in chick ocular tissues, cartilaginous sclera is abbreviated as CS.