Ultrastructural immunohistochemical localization of anti-invasion factor (AIF) in bovine cartilage matrix

Abstract

Rabbit antibodies prepared against bovine cartilage anti-invasion factor (AIF) were tested for their affinity toward antigenic sites in glutaraldehyde-fixed bovine hyaline cartilage matrix. Ultrastructural localization of the antigen-antibody complex was accomplished by the unlabeled antibody peroxidase-antiperoxidase staining technique. Unextracted and salt-extracted (1 M NaCl or 3 M GuHCl) cartilage slices were incubated with anti-AIF antibodies at a working dilution of 1:20,000. Staining occurred in unextracted matrix distributed throughout the tissue, but with regional variation in the lacunar matrix. Significantly less stain was noted in extracted tissues. The results suggest that at least certain protein components in AIF are morphologically associated with matrix complexes in aldehyde-fixed tissue.