What keeps cartilage stuck to bone? Bonding at the osteochondral junction investigated with multimodal imaging, materials testing, and macromolecule characterisation.

Abstract

The osteochondral junction is vitally important to the structural integrity of synovial joints. The cement line between bone and cartilage is a highly mineralised, undulating plane through which cartilage’s type-II collagen fibres pass. Samples devoid of mineral, and other samples devoid of organic material, remain bonded, indicating that both mineral and organic phases contribute to the tight hold cartilage has on underlying bone. The student will use confocal microscopy, X-ray microtomography, focussed ion-beam scanning electron microscopy to image the cement line, nanoindentation to test mechanical properties of cement line, and protein purification to determine cross-linking between type-I and -II collagens.

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