The concentration, gene expression, and spatial distribution of aggrecan in canine articular cartilage, meniscus, and anterior and posterior cruciate ligaments: a new molecular distinction between hyaline cartilage and fibrocartilage in the knee joint.

The concentration, spatial distribution, and gene expression of aggrecan in meniscus, articular cartilage, and the anterior and posterior cruciate ligaments (ACL and PCL) was determined in the knee joints of five mature dogs. An anti-serum against peptide sequences specific to the G1 domain of aggrecan was employed in competitive-inhibition ELISA of guanidine HCl extracts and immunofluorescence microscopy. Gene expression was determined by Taqman real-time PCR.

Spatial organization of types I and II collagen in the canine meniscus.

The meniscus of the knee joint is a fibrocartilage mainly composed of type I collagen and smaller amounts of type II collagen. The distribution of type II collagen in the canine meniscus and its spatial relationship to type I collagen was examined by immunohistochemistry and confocal microscopy. Dorsal and coronal slices of the mid-section of medial and lateral menisci from the knee joints of skeletally mature dogs were predigested with Streptomyces hyaluronate lyase and bacterial Protease enzyme XXIV.

Transforming growth factor-beta1 in a sterilized tissue derived from the pig small intestine submucosa.

The extracellular matrices of connective tissues contain growth factors such as transforming growth factor (TGF)-beta1. The possibility arises, therefore, that animal connective tissues that have been excised and rendered acellular in the sterilization, lyophilization, and other preparative processes for human use may still retain active growth factors that could contribute to the clinical efficacy of the product. We therefore analyzed 4M guanidine HCl extracts of a sterilized, acellular matrix, Oasis Wound Matrix, for the presence of TGF-beta1 by a sandwich enzyme-linked immunosorbent assay using the soluble type II receptor for TGF-beta to capture the growth factor, and for biological activity by testing the capacity of the extracts to inhibit 3[H]thymidine incorporation into Mv1Lu cells (mink lung epithelial cells).