Immunogenic properties of glucosylceramide

Genetic and nongenetic control of the immune response of mice to a synthetic glycolipid, stearylisomaltotetraose

Evidence for genetic control of antibody response to stearylisomaltotetraose (ST-IM4), a chemically defined synthetic glycolipid, was studied in various mouse strains. Anti-glycolipid antibodies were induced by repeated injections of ST-IM4 in complete Freund's adjuvant. C57BL and CBA/J mice were found to be good responders, while A/J, SJL/J, and AKR/J mice were poor responders. Responsiveness is independent of the H-2 genotype since AKR/J and CBA/J mice share the same H-2 locus. In addition, B10.A and B10.PL mice developed antibody levels similar to those of C57BL. The immunoglobulin heavy-chain locus (IgCH) was also found not to control antibody levels to ST-IM4 since C57BL and SJL/J mice share the same IgCH allotype. In C58/J mice, wide variation in response was observed among individual mice. Study of the response to ST-IM4 in 12 breeder pairs from different family lines of the C58/J colony also indicated that the regulation of the immune response to ST-IM4 is apparently more complex than can be explained by single gene control. C58 mice, unlike many other strains, had very low preimmune titers.

Immunochemical studies of conjugates of isomaltosyl oligosaccharides to lipid. I. Antigenicity of the glycolipids and the production of specific antibodies in rabbits

Isomaltose oligosaccharides varying in size from two sugars, isomaltose (IM2), to seven sugars, isomaltohepatose (IM7), were coupled to stearylamine by reductive amination with sodium cyanoborohydride. Each compound was purified by column chromatography to yield a series of glycolipids containing oligosaccharides differing in length. Stearyl-isomaltotriose to stearyl-IM7 could be incorporated into liposomes and could render them agglutinable by specific antibodies to alpha 1 leads to 6 dextran and could be lysed if complement was also added, whereas those containing stearyl-IM2 were not agglutinated or lysed, indicating that stearyl-IM2 may not be protruding from the liposome surface sufficiently to react with the antibody. Stearyl-isomaltosyl oligosaccharides by themselves or incorporated into liposomes were equally antigenic when emulsified in complete Freund's adjuvant. They elicited pauciclonal responses, and the antibodies were alpha 1 leads to 6 specific, cross-reacted with dextran, and gave semirestricted isoelectric focusing patterns.

Immunohistochemical localization of galactosyl and sulfogalactosyl ceramide in the brain of the 30-day-old mouse

We have used purified antibodies against galactosylceramide (galCb) and sulfogalactosylceramide (sulf) to study the topographical distribution of these two lipid haptens in the brain of the 30-day-old mouse. This study has been conducted, using the indirect immunofluorescence method, on cerebellum, brain stem and hemispherical tissue sections. Both haptens are present in the myelin sheaths and in the oligodendrocytes within the myelinated bundles. Cortical oligodendrocytes as well as some of the subependymal cells are also galCb-positive but sulf-negative. On the contrary, ciliated ependymal cells and subpial astrocytic processes (especially the Bergmann glia fibers in the cerebellum) are sulf-positive and galCb-negative. Astrocyte cell bodies and other astrocytic cell processes are devoid of both haptens. Lastly, some-sulf positive galCb-negative processes, as yet unidentified, were also found in the periaqueductal gray matter and in the nucleus interpeduncularis.

Expression of antigenic markers during the development of oligodendrocytes in mouse brain cell cultures

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.

Immunological properties of bulk isolated mouse oligodendrocytes

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.