Preservation of oligodendroglial cytoplasm in cryopreservative-pretreated frozen white matter

Monoclonal antibody 14E identifies the oligodendrocyte cell body in normal adult human and rat white matter

A monoclonal antibody, 14E, which detects immunocytochemically the perikarya of interfascicular oligodendrocytes in sections of normal adult human and rat white matter, was obtained using isolated normal human oligodendrocytes as the immunogen. 14E is an IgM antibody that reacts with a polypeptide of approximate molecular weight 23,000 on immunoblots of the particulate fraction of normal white matter. In sections of active multiple sclerosis plaques and recent infarcts, 14E immunostained the cell bodies and processes of only a small number of hypertrophic glial cells which could be oligodendrocytes undergoing pathological changes or a subpopulation of reactive astrocytes.

Incorporation of [14C]glucose into lipids of bovine oligodendroglia

Oligodendrocytes were isolated from the white matter of ox brains. Light microscopy revealed that the cells were greater than or equal to 90% phase-bright with a mean diameter of 7.6 micron. Transmission electron microscopy was employed to identify the classic morphology associated with mature oligodendrocytes. Homogenates of the isolated cells showed negligible activity of neuronal and astrocytic cell markers. Using a suspension culture method cells were incubated with [14C]glucose. This simple precursor labelled the five complex lipids choline glycerophospholipid, ethanolamine glycerophospholipid, inositol glycerophospholipid + serine glycerophospholipid, and the two cerebroside species. The incorporation of label was shown to be dependent on glucose concentration, protein concentration, and the length of incubation. In addition the glucose uptake blocker phloretin (1 mM) reduced the degree of labelling by up to 97%, and the metabolic poisons KCN (1 mM) and iodoacetate (0.5 mM) had varying deleterious effects on the amounts of labelling of the five lipids measured.

Synthesis of gluco- and galactocerebrosides in bovine neurones and oligodendroglia

Oligodendroglial and neuronal perikarya have been isolated from fresh and frozen bovine brain and used to investigate the synthesis of cerebrosides from UDP-hexoses and ceramides. The radioactive cerebrosides produced have been identified by TLC of the intact lipids on borate-silica gel and by a combination of acid hydrolysis and ion-exchange chromatography of the liberated hexoses. Incubation of either neuronal or oligodendroglial homogenates with UDP-galactose (UDP-gal) and mixed ceramides (hydroxy plus nonhydroxy fatty acids) leads to the synthesis of hydroxy fatty acid galactocerebroside. This lipid is also formed by both neuronal and oligodendroglial homogenates if the UDP-gal is replaced by UDP-glucose (UDP-glu). Formation of glucocerebroside has been observed only in the presence of neuronal homogenates and UDP-glu. Electron microscopic examination of the isolated cell preparations has shown that, although the oligodendroglia are relatively pure, the neurones are contaminated with oligodendroglia, which may account for some of the hydroxy fatty acid galactocerebroside synthesis. When unlabelled UDP-gal is included in the incubations containing cell homogenates, mixed ceramides, and labelled UDP-glu, galactocerebroside formation is greatly reduced, but there is comparatively little effect on glucocerebroside synthesis. In addition, experiments using D-[14C]galactose 1-phosphate and UDP D-[6-3H]glucose simultaneously have shown that the rate of formation of tritiated cerebroside is much greater than that of the 14C-labelled compound.(ABSTRACT TRUNCATED AT 250 WORDS)