Aspects of the glycome of endochondral ossification

Abstract

Comparatively little is known about the glycome (the set of glycans and glycoconjugates made by the cell, tissue or organism) of bone and cartilage. The glycome has a high-density coding capacity and is important in post-translational modification. Lectin histochemistry provides insights into the glycome and we applied this technique to an ectopic ossification site in human bronchial cartilages.Our results show that cartilage matrix at the site of erosion by chondroclasts has a limited but definite glycoprofile. In contrast, bone matrix does not express many lectin ligands. Chondroclasts have an extensive glycoprofile similar to that of, but not identical to, osteoclasts. N and O glycans are both expressed in the zone of presumptive mineralization and are relevant to that process. Bone trabecular lining cells communicate with osteocytes via intracanalicular processes and some lectin ligands were expressed by these three components.Mast cells and angiogenesis were prominent. Since cartilage normally resists vascular penetration by the secretion of antiangiogenesis factors it is postulated that the hypertrophic chondrocytes in the mineralization zone produce proteases which inhibit antiangiogenesis and facilitate angiogenesis by mast cells.

High-Resolution N-Glycan MALDI Mass Spectrometry Imaging of Subchondral Bone Tissue Microarrays in Patients with Knee Osteoarthritis

“…Furthermore, a recent study demonstrated that different lectin immunohistochemistry staining is present in osteoblasts/trabecular bone lining cells, osteocytes, and osteoclasts . Interestingly, they reported that the bone matrix generally did not stain with lectins.…”

“…Furthermore, a recent study demonstrated that different lectin immunohistochemistry staining is present in osteoblasts/ trabecular bone lining cells, osteocytes, and osteoclasts. 36 Interestingly, they reported that the bone matrix generally did not stain with lectins. However, there were non-bisected biand tri-antennary complex-type N-glycans predominantly stained in all of the osteoblast/trabecular bone lining cells, osteocytes, and osteoclasts (via Pisum sativum agglutinin; PSA staining) by showing positive staining of cytoplasm and cell membranes.…”

“…However, there were non-bisected biand tri-antennary complex-type N-glycans predominantly stained in all of the osteoblast/trabecular bone lining cells, osteocytes, and osteoclasts (via Pisum sativum agglutinin; PSA staining) by showing positive staining of cytoplasm and cell membranes. 36 The staining of trabecular bone lining cells and osteocytes with PSA is of particular significance, where there were processes of the osteocytic canalicular communicating with the bone surface layer.…”

Chondro/osteoclasts and mast cells are co-villains in the joint destruction of rheumatoid arthritis

“…We applied the lectin lPHA to tissue sections in the present study since we have previously shown that clast and mast cells and endothelial cells stain positively with this lectin (10,11). The specific ligand is the β1-6 branching linkage in complex N-glycans and is formed by the action of N-acetylglucosaminyltransferase-V (GnTase V/MGAT5).…”

“…Paraffin wax-embedded tissue blocks were prepared by conventional techniques. Thin sections were variously stained with haematoxylin and eosin (H & E), for mast cell tryptase and with the lectins lPHA and PTL-11 (10,11).…”