Summary
The distribution of myelin-associated glycoprotein (MAG) was examined by immunocytochemistry in the spinal cord, accessory cuneate nucleus and lumbar ventral nerve roots of dogs affected by progressive axonopathy. These areas were chosen because of the frequency of spheroids and the associated changes in the myelin sheath, including vacuolation, demyelination, remyelination and accumulation of a granular, amorphous material within the sheath. Normal animals demonstrated the expected distribution of MAG; periaxonal and associated with uncompacted membrane such as Schmidt-Lanterman incisures. The majority of early axonal spheroids were surrounded by a MAG-positive zone but in the larger swellings and longer duration cases this was sometimes absent in places even though the axon was associated with Schwann cell processes. Axons in vacuolated fibres were commonly surrounded by a single adaxonal process of Schwann cell and normal periaxonal space. This was immunoreactive for MAG but in situations where the process was incomplete or the space distorted, staining was absent. The granular material failed to stain for MAG. Distorted Schmidt-Lanterman incisures, a feature of the advanced disease, were strongly positive. In the CNS, spheroids without myelin sheaths or unassociated with oligodendroglial processes were negative for periaxonal MAG. The study confirms the localization of MAG at the periaxonal space. It also raises the question of how the distribution of periaxonal MAG is affected by axonal swelling with a consequent increase in axonal surface area.
Similar content being viewed by others
References
Adams, J. C. (1981) Heavy metal intensification of DAB-based HRP reaction product.Journal of Histochemistry and Cytochemistry 29, 775.
Friede, R. L. &Miyagishi, T. (1972) Adjustment of the myelin sheath to changes in axon caliber.Anatomical Record 172, 1–14.
Griffin, J. W. &Price, D. L. (1981) Demyelination in experimental β, β-iminodipropionitrile and hexacarbon neuropathies. Evidence for an axonal influence.Laboratory Investigation 45, 130–41.
Griffiths, I. R., McCulloch, M. C. &Abrahams, S. (1985) Progressive axonopathy: an inherited neuropathy of Boxer dogs. 2. The nature and distribution of the pathological changes.Neuropathology and Applied Neurobiology 11, 431–46.
Griffiths, I. R., McCulloch, M. C. &Abrahams, S. (1986) Progressive axonopathy: an inherited neuropathy of Boxer dogs. 3. The peripheral axon lesion with special reference to the nerve roots.Journal of Neurocytology 15, 109–20.
Griffiths, I. R., McCulloch, M. C. &Abrahams, S. (1987) Progressive axonopathy: an inherited neuropathy of Boxer dogs. Myelin sheath and Schwann cell changes in the nerve roots.Journal of Neurocytology 16, 145–53.
Kruse, J., Mailhammer, R., Wernecke, H., Faissner, A., Sommer, I., Goridis, C. &Schachner, M. (1984) Neural cell adhesion molecules and myelin-associated glycoprotein share a common carbohydrate moiety recognised by monoclonal antibodies L2 and HNK-1.Nature 311, 153–5.
Martini, R. &Schachner, M. (1986) Immunoelectron microscopic localisation of neural cell adhesion molecules (L1, N-CAM and MAG) and their shared carbohydrate epitope and myelin basic protein in developing sciatic nerve.Journal of Cell Biology 103, 2439–48.
McGarry, R. C., Helfard, S. L., Quarles, R. H. &Roder, J. C. (1983) Recognition of myelin-associated glycoprotein by the monoclonal antibody HNK-1.Nature 306, 376–8.
Quarles R. H. (1979) Glycoproteins in myelin and myelin-related membranes. InComplex Carbohydrates of Nervous Tissue (edited byMargolis, R. U. &Margolis, R. K.), pp. 109–233. Plenum Press: New York.
Quarles, R. H., Barbarash, G. R. &MacIntosh, T. D. (1984) Methods for the identification and characterisation of glycoproteins in central and peripheral myelin. InRecent Methods in Neurochemistry (edited byMark, N. &Rodnight, R.), Vol. 6, pp. 303–57. Plenum Press: New York.
Quarles, R. H., Johnson, D., Brady, R. O. &Sternberger, N. H. (1981) Preparation and characterisation of antisera to the myelin-associated glycoprotein.Neurochemistry Research 6, 1109–21.
Sternberger, L. A., Hardy, P. H. Jr., Cuculis, J. J. &Meyer, H. G. (1970) The unlabelled antibody-enzyme method of immunocytochemistry. Preparation and properties of soluble antigen-antibody complex (horseradish peroxidase-antihorseradish peroxidase) and its use in identification of spirochetes.Journal of Histochemistry and Cytochemistry 18, 315–33.
Sternberger, N. H., Quarles, R. H., Itoyama, Y. &Webster, H. De F. (1979) Myelin-associated glycoprotein demonstrated immunocytochemically in myelin and myelin-forming cells of developing rat.Proceedings of the National Academy of Sciences (USA) 76, 1510–14.
Trapp, B. D., Itoyama, Y., Sternberger, N. H., Quarles, R. H. &Webster, H. De F. (1981) Immunocytochemical localisation of Po protein in Golgi complex membranes and myelin of developing rat Schwann cells.Journal of Cell Biology 90, 1–6.
Trapp, B. D. &Quarles, R. H. (1982) Presence of the myelin-associated glycoprotein correlates with alterations in the periodicity of peripheral myelin.Journal of Cell Biology 92, 877–82.
Trapp, B. D. &Quarles, R. H. (1984) Immunocytochemical localisation of the myelin associated glycoprotein. Fact or artifact?Journal of Neuroimmunology 6, 231–49.
Trapp, B. D., Quarles, R. H. &Griffin, J. W. (1984a) Myelin-associated glycoprotein and myelinating Schwann cell-axon interaction in chronic β, β-iminodipropionitrile neuropathy.Journal of Cell Biology 98, 1271–8.
Trapp, B. D., Quarles, R. H. &Suzuki, K. (1984b) Immunocytochemical studies of quaking mice support a role for the myelin-associated glycoprotein in forming and maintaining the periaxonal space and periaxonal cytoplasmic collar of myelinating Schwann cells.Journal of Cell Biology 99, 594–606.
Webster, H. De F., Pulkovits, C. G., Stoner, G. L., Favilla, J. T., Frail, D. E. &Braun, P. E. (1983) Myelin-associated glycoprotein: Electron microscopic immunocytochemical localisation in compact developing and adult central nervous system myelin.Journal of Neurochemistry 41, 1469–79.
Willison, H. J., Ilyas, A. L., O'Shannessy, D. J., Pulley, M., Trapp, B. D. &Quarles, R. H. (1987) Myelin-associated glycoprotein and related glycoconjugates in developing cat peripheral nerve: A correlative biochemical and morphometric study.Journal of Neurochemistry 49, 1853–62.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Griffiths, I.R., Kyriakides, E. & Abrahams, S. The distribution of MAG in association with the axonal lesions of canine progressive axonopathy. J Neurocytol 18, 353–358 (1989). https://doi.org/10.1007/BF01190838
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01190838