Application of cryotechniques in cartilage tissue preservation and immunoelectron microscopy: potentials and problems

Cryotechnical processing of cartilage has the potential to solve many of the tissue-specific problems associated with various routine chemical fixation protocols. This is particularly the case with respect to extracellular matrix architecture, the distortion or destruction of which (caused by extraction and/or precipitation of proteoglycan molecules) may be prevented. Adoption of such techniques also permits high-sensitivity immunoelectron-microscopy of the extracellular matrix space (carbohydrate epitopes). However, a number of difficulties still remain to be resolved, particularly that of matrix-cell interface separation occurring during freeze substitution and low temperature embedding. These problems are briefly addressed and possible solutions outlined.