ABSTRACT
Brain sections and dissociated brain cell cultures of jimpy mouse (jp) were investigated for the presence of galactosylceramide (GC) by indirect immunofluorescence. Optic nerve and corpus callosum sections of 26-day-old jp exhibited many GC-positive cells. The GC staining pattern was similar in jp and normal cultures of the same age. These data suggest that the previously observed decreased amount of GC in jp brain is due to the inability of jp oligodendroglia to properly deposit GC in the myelin, while its synthesis is possible.
Subject(s)
Brain Chemistry , Cerebrosides/analysis , Galactosylceramides/analysis , Neuroglia/analysis , Oligodendroglia/analysis , Animals , Cells, Cultured , Fluorescent Antibody Technique , Mice , Mice, Jimpy , Optic Nerve/analysisABSTRACT
The expression of myelin basic protein (MBP) and galactocerebroside (GC), two antigenic markers for oligodendrocytes, was checked on 7-, 14-, 21- and 28-day-old dissociated mouse brain cell cultures (BCC) by using the indirect immunofluorescence method with double staining. The number of GC positive cells increased between the 7th and the 14th day of culture before a steady state was reached. In contrast to this, the MBP-positive cells appeared only on the 14th day of culture, and their number increased with the age of the culture. In double staining, the serum produced against isolated oligodendrocytes shows the same picture as the anti-GC serum, while only a part of GC-positive cells showed also the presence of MBP. Our data suggest that the GC appears very early on the membrane of the oligodendrocytes during development while cells exhibiting both GC and MBP probably represent a more differentiated oligodendrocyte population.
Subject(s)
Antigens, Surface/analysis , Brain/physiology , Neuroglia/physiology , Oligodendroglia/physiology , Animals , Animals, Newborn , Cells, Cultured , Fluorescent Antibody Technique , Immune Sera , Kinetics , MiceABSTRACT
Mouse oligodendrocytes were isolated in bulk. These cells were 95% galactocerebroside-positive. Rabbit anti-mouse oligodendrocyte antisera reacted in radioimmunoassay and in indirect immunofluorescence with mouse oligodendrocytes in suspension or in culture. The activity of the sera was not blocked by adsorption with galactocerebroside or by preincubation of cells with anti-galactocerebroside serum, although it cross-reacted with galactocerebroside in a serological test. The staining was not impaired by the pretreatment of cells with trypsin, neuraminidase or acetone, nor by adsorption of serum with myelin basis protein.
Subject(s)
Cerebrosides/analysis , Galactosylceramides/analysis , Neuroglia/analysis , Oligodendroglia/analysis , Animals , Cells, Cultured , Fluorescent Antibody Technique , Immune Sera , Mice , RadioimmunoassayABSTRACT
Several metabolic activities in dissociated cultures of newborn mouse brain were compared to the situation in vivo. The developmental activity pattern of cerebroside-sulfotransferase, cyclic nucleotide phosphohydrolase, and beta-hydroxy-beta-methyl glutaryl-coenzyme A-reductase and the synthesis and deposition of sulfatide and cholesterol in culture were estimated. The enzyme activity patterns in vivo and in culture are the same. Since the cultures show very little myelin formation, the parallel increase of enzyme activities necessary for myelination in vivo and in culture suggest the existence of intrinsic factors regulating the biochemical differentiation. In addition, the formation of the products, determined in culture, follows the patterns of the enzyme activities. Dissociated brain cell cultures are therefore a valid model for the study of biochemical parameters related to the synthesis of brain lipids during development.
