OBJECTIVE: To explore the genotype-phenotype correlation of a case with GM1-gangliosidosis caused by compound heterogenic variants in GLB1. METHODS: Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Trio-based whole-exome sequencing (WES) was performed for the family and suspected mutation was verified by Sanger sequencing. RESULTS: The proband, a 2-year-3-month old Chinese girl, presented with psychomotor deterioration, absent speech, intellectual disabilities and behavior problem. Trio-based WES has identified compound heterozygosity for 2 variants in the GLB1 gene: NM_000404.2:c.1343A>T, p.Asp448Val and c.1064A>C, p.Gln355Pro (GRCh37/hg19),which was inherited from the mother and father, respectively. Homozygous or compound heterozygous pathogenic variants in GLB1, encoding β-galactosidase, are responsible for GM1-gangliosidosis,an autosomal recessive lysosomal storage disorder characterized by variable degrees of neurodegeneration and skeletal abnormalities. The p.Asp448Val variant has been classified as pathogenic for GM1 gangliosidosis in medical literatures for the reason that functional studies demonstrated that expression of the p.Asp448Val variant in COS-1 cells resulted in no detectable β-galactosidase activity compared to wild type GLB1. The p.Gln355Pro variant has not been reported in literatures or database. The variant is highly conserved residue (PM1), and was not found in either the Genome Aggregation Database or the 1000 Genomes Project (PM2) and was predicted to have a deleterious effect on the gene product by multiple in silico prediction tools (PP3). Next, the β-galactosidase activity of the patient's peripheral blood leukocytes was determined by fluorescent method. The result was 0.0 nmol/mg. It showed that the p.Gln355Pro variant also resulted in loss of β-galactosidase activity, thus the variant was classified into clinical pathogenic variant. CONCLUSION Our study expands the mutational spectrum of the GLB1 gene and provides genetic counseling for the family.
Asians/genetics* ; China ; Female ; G(M1) Ganglioside ; Gangliosidosis, GM1/genetics* ; Humans ; Mutation ; beta-Galactosidase/genetics*

The acute peripheral neuropathy as one of hypereosinophilic syndrome is known to be a rare disorder. The authors experienced a dramatic case with acute peripheral neuropathy, hypereosinophilia in peripheral blood, and the positive anti-GM1 antibodies. The serum protein electrophoresis showed a diffusely increased gamma-globulin region and the polyclonal gammopathy was found by the immunoelectropheresis. There was no evidence of inflammatory myopathy in vastus lateralis muscle. The sural nerve biopsy was compatible with vascular neuropathy, as there were a few myelin digestion chambers, mild perineuronal fibrosis, and perivascular lymphoplasmocytic infiltration with focal organizing thrombosis. The clinical response to prednisone therapy was excellent.
Acute Disease ; Adult ; Antibodies/*blood ; G(M1) Ganglioside/*immunology ; Humans ; Hypereosinophilic Syndrome/*complications/immunology ; Male ; Peripheral Nervous System Diseases/*etiology

A fusion gene CTB-PROIN, in which Proinsulin gene was fused to the 3' end of CTB gene by a hinge peptide 'GPGP', was constructed and cloned into pET-30a(+) to obtain a prokaryotic expression vector pETCPI. Subsequently the recombinant plasmid pETCPI was transformed into E. coli stain BL21 (DE3). After induced by IPTG, the expression product was analyzed by sodium dodecyl sulphate-polyacrylamide gel (15%) electrophoresis (SDS-PAGE), and its result indicated that the recombinant protein CTB-PROIN was expressed and accumulated as inclusion bodies. The recombinant CTB-PROIN protein accumulated to the level of 25% of total bacterial proteins. After inclusion bodies was denaturalized and refolded in vitro, significant assembly of monomers had occurred, and the recombinant protein represented assembled pentamers. The results of western blotting analysis also demonstrated that the fusion protein could be recognized by the anti-CT and anti-insulin antibody, respectively. In addition, the result of the CTB-PROIN-GM1 binding assay, that the protein could bind to monosialoganglioside specifically, showed it possesed biological activity in vitro. These results provided the possibility of developing a cheaper and more efficient oral vaccine for type I diabetes using such constructs.
Artificial Gene Fusion ; Cholera Toxin ; genetics ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; G(M1) Ganglioside ; metabolism ; Proinsulin ; genetics ; Recombinant Proteins ; biosynthesis ; genetics

OBJECTIVEA comparative study on the role of Campylobacter jejuni (CJ) HB9313 and galE mutant in inducing experimental sciatic nerve damage was conducted in guinea pigs in order to explore whether CJ lipo-oligosaccharide (LOS) is critical component associated with peripheral nerve lesions and find experimental evidence for the presumption of molecular mimicry on the pathogenesis of Guillain-Barre syndromes (GBS) with CJ antecedent infection.

METHODSA total of 32 guinea pigs were randomly divided into four groups: parental strain group (n = 10), galE mutant group (n = 10), control group (n = 6) and PBS group (n = 6), and immunized with the whole cell antigens of CJ HB9313 with Freund's adjuvant (FA), the whole cell antigens of galE mutant (without ganglioside-like structure) with FA, PBS with FA, and PBS alone, respectively. Enzyme-linked immunosorbent assay (ELISA) was employed to detect anti-LOS and anti-ganglioside GM1 antibodies in sera of these animals, and comparative morphologic studies of pathologic changes were carried out on the sciatic nerves, including examination of teasing fibers, examination of semithin sections made from epon-embedded tissue blocks under light microscope and transmission electron microscope.

RESULTSELISA results indicated that after immunization, the levels of anti-LOS IgG antibody were significantly elevated in animals from parental strain group and galE mutant group as compared with those before immunization (P < 0.01). No statistically significant difference was found between the two groups. However, the mean optical densities (ODs) of IgG antibody against GM1 at 14 and 28 day after immunization, in parental strain group, were 0.661 +/- 0.290 and 0.984 +/- 0.025, respectively, significantly higher than those of galE mutant group, which were 0.193 +/- 0.078 and 0.180 +/- 0.063 (P < 0.01). The results of morphologic examination on sciatic nerves showed that for teased-fiber study, incidence of pathologic abnormalities of teased fibers from animals of galE mutant group was 4.9% (98/2000), significantly lower than that from parental strain group, which was 16% (320/2000), characterized by predominantly axonal degeneration. The difference between them was highly significant statistically (P < 0.01). Examination of semithin sections of sciatic nerves also revealed that obvious pathological changes occurred in the animals from parental strain group, while only minimal abnormalities could be seen from galE mutant group, there was a significant differences between them (P < 0.01). In parental strains group, the predominant pathologicanl change was axonal degeneration with considerable variation in severity. These morphologic changes were confirmed by electron microscopy.

CONCLUSIONCompared with parental strain, galE mutant without ganglioside-like structure no longer could induce anti-GM1 antibodies, nor induce obvious immune damage of peripheral nerves in experimental guinea pigs. The results of this study provide a strong support to the hypothesis of molecular mimicry as a pathogenesis in patients with GBS following CJ antecedent infection.

Animals ; Antibodies, Bacterial ; blood ; Campylobacter jejuni ; genetics ; immunology ; pathogenicity ; G(M1) Ganglioside ; immunology ; Guillain-Barre Syndrome ; etiology ; Guinea Pigs ; Immunization ; Lipopolysaccharides ; immunology ; UDPglucose 4-Epimerase ; physiology

AIMTo investigate the protective effect of monosialoganglioside (GM1) on injury induced by oxygen glucose deprivation/reperfusion (OGD/Rep) in rat hippocampal slices.

METHODSThe protective effects of GM1 on hippocampal slices after OGD/Rep were observed by detecting the light transmittance (LT) changes of rat hippocampal slices and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining of rat hippocampal slices.

RESULTS(1) In four groups treated with 0 (control), 0.1, 1.0, 10 micromol/L GM1, the peak of light transmittance (LT) in the slices treated with 1.0 micromol/L GM1 was significantly lower than that of the control and the group treated with 0.10 micromol/L GM1 (P < 0.01, ANOVA), while the peak of LT in the slices treated with 10.0 micromol/L GM1 was significantly lower than that of the other groups (P < 0.01, ANOVA). The time to reach the peak of LT in four groups was significantly different from each other (P < 0.05, Kruskal-Wallis test). The time to reach the peak of LT in the group treated with 1 micromol/L GM1 was the significantly longer than that in the control (P < 0.01, Mann-Whitney U test). (2) There was characteristic dose-response relationship between GM1 and TTC staining of rat hippocampal slices. In the five groups, treated with 0 (control), 0.01, 0.1, 1.0, 10 micromol/L GM1 respectively, TTC staining in the group treated with 1 micromol/L GM1 was the deepest (P < 0.05 vs. control, 0.01 and 0.1 micromol/L GM1 group, ANOVA), and the next was in the group treated with 10 micromol/L GM1 (P < 0.05 vs. control and 0.01 micromol/L GM1 group, ANOVA).

CONCLUSIONGM1 could protect injury induced by OGD/Rep in rat hippocampal slices effectively in vitro.

Animals ; G(M1) Ganglioside ; pharmacology ; Glucose ; deficiency ; Hippocampus ; metabolism ; Hypoxia ; metabolism ; In Vitro Techniques ; Male ; Oxygen ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury

To explore the role of lipid raft in assembly of human herpesvirus 6, the HHV-6 GS strain was applied to infect the HSB2 cells and then the lipid raft composition was extracted from the cells with non-ionic detergent Triton-X 100. The relationship between the HHV-6 envelope glycoprotein and lipid raft was analyzed by Western Blot. Immunofluorescence double-staining was used to study the colocalization of the HHV-6 glycoprotein B(gB) with GPI anchored protein CD59 and ganglioside GM respectively. HHV-6 envelope glycoprotein B, H, L, Q1 and Q2 (gB, gH, gL, gQ1 and gQ2) were all existed in the lipid raft. Moreover, CD59 and HHV-6 envelope glycoprotein B showed the same localization through the confocal microscope. We concluded the lipid raft provided the platform for HHV-6 assembly. This is the first report concerning to the role of lipid raft in assembly of human Herpesvirus 6.
CD59 Antigens ; analysis ; Fluorescent Antibody Technique ; G(M1) Ganglioside ; analysis ; Herpesvirus 6, Human ; physiology ; Membrane Microdomains ; physiology ; Viral Envelope Proteins ; analysis ; Virus Assembly

Human neuroblastoma SH-SY5Y cell is a cloned cell line which has many attractive features for the study of neuronal proliferation and neurite outgrowth, because it has receptors for insulin, IGF-I and PDGF. Gangliosides are sialic acid containing glycosphingolipids which form an integral part of the plasma membrane of many mammalian cells. They inhibit cell growth mediated by tyrosine kinase receptors and ligand-stimulated tyrosine kinase activity, and autophosphorylation of EGF(epidermal growth factor) and PDGF receptors. The experiment was designed to study the effects of GM1 ganglioside on growth of human neuroblastoma SH-SY5Y cells stimulated with trophic factor in vitro. The cells were plated in Eagle's minimum essential medium without serum. The number and morphologic change of SH-SY5Y cells were evaluated in the serum free medium added GM1 ganglioside with insulin or PDGF. SH-SY5Y cells were maintained for six days in serum-free medium, and then cultured for over two weeks in serum-free medium containing either insulin or PDGF. The effect of insulin on cell proliferation developed earlier and was more potent than that of PDGF. These proliferative effects were inhibited by GM1 ganglioside, and the cells showed prominent neurites outgrowth. These findings suggest that GM1 ganglioside inhibits the cell proliferation mediated by tyrosine kinase receptors and directly induces neuritogenesis as one of the neurotrophic factors.
Cell Differentiation/drug effects ; Cell Division/drug effects ; G(M1) Ganglioside/*pharmacology ; Humans ; Insulin/pharmacology ; Neuroblastoma ; Neurons/cytology/*drug effects ; Platelet-Derived Growth Factor/pharmacology ; Receptor Protein-Tyrosine Kinases/drug effects ; Tumor Cells, Cultured

OBJECTIVETo explore the important role of the terminal residues containing sialic acid (SA) in Campylobacter jejuni (CJ) lipopolysaccharide (LPS) as the critical antigen to induce nerve damage, and also to identify immunopathological evidence for the hypothesis of molecular mimicry and cross-immunity between CJ LPS and gangliosides.

METHODSA mutant of Pen O:19 CJ with neuB1 gene inactivated and LPS outer core terminal residues losing SA was to be constructed. PCR and RT-PCR were used to confirm the mutant. Capability of CJ LPS binding to cholera toxin B subunit (CTB) was tested. Guinea pigs were systematically immunized with LPS of the wild and the mutant strains, respectively. Titers of anti-LPS and anti-ganglioside GM(1) IgG antibodies in sera of immunized guinea pigs were detected by ELISA. Pathological study for sciatic nerves of both Guinea pigs either immunized systematically or perineural injection with their immunized serum was finished.

RESULTS(1) The mutant of CJ O:19 strain with inactivated neuB1 gene was successfully constructed and lost transcriptional activity of neuB1 gene in the mutant strain was confirmed by PCR and RT-PCR. SA was well demonstrated by both acidic ninhydrin reaction and periodate-resorcinol reaction in the LPS of wild strain but not in the mutant LPS; (2) Compared with the titers before immunization, the titers of anti-GM(1) IgG antibody increased in sera of guinea pigs immunized with LPS of the wild strain. However there were no detectable anti-GM(1) IgG antibody in sera of the animals immunized with mutant LPS and PBS. (3) The incidence of pathological fibers of sciatic nerves in wild CJ LPS group (17.3%) was significantly higher than the mutant CJ LPS group (chi(2) = 125, P < 0.01); the difference between the mutant CJ LPS group and control group was not statistically significant (chi(2) = 1.633, P > 0.05). (4) After perineural injection with immunized serum, the incidence of pathological fibers of sciatic nerves in wild strain group (67.8%) was also significantly higher than the incidence of mutant group (P < 0.01).

CONCLUSIONA mutant of CJ O:19 strain neuB1 gene inactivated and SA component of terminal structure of LPS lost was successfully constructed. And it no longer expressed SA component which is the normal terminal structure of LPS in wild strain. The capability of the wild strain to induce increased titers of anti-GM(1) antibody and immune-mediated nerve damage was simultaneously lost for the mutant strain. It could be a strong immunopathologic evidence to identify the molecular mimicry hypothesis between CJ LPS and ganglioside epitope in nerve on the pathogenesis of CJ related GBS. The terminal residues containing SA should be as the basic GM1-like structure in CJ LPS.

Animals ; Antibodies, Bacterial ; blood ; immunology ; Antigens, Bacterial ; genetics ; immunology ; Campylobacter jejuni ; genetics ; immunology ; G(M1) Ganglioside ; immunology ; Guinea Pigs ; Lipopolysaccharides ; chemistry ; immunology ; Molecular Mimicry ; Mutagenesis ; N-Acetylneuraminic Acid ; chemistry ; immunology ; Peripheral Nervous System Diseases ; immunology ; microbiology

OBJECTIVETo investigate the effects of GM1 on inducing adult rat bone marrow stromal cells (MSCs) to form neural progenitor cells and their differentiation.

METHODSPurified MSCs were induced by different components of basic fibroblast growth factor (bFGF) alone, GM1 alone or combination of bFGF with GM1. After 3 days' incubation, fibronectin and collagen I were detected with immunocytochemistry, and nestin was detected with immunofluorescence. Neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP) and galactose cerebroside (GalC) were detected with immunocytochemistry after 7 days' incubation.

RESULTSAfter induction with bFGF alone or combination of bFGF and GM1, some MSCs exhibited the phenotypes of neural progenitor cells, and then neurons and astrocytes. In these two groups, the positive cells for fibronectin and collagen I decreased markedly after 3 days' induction. At the same time, the positive cells for nestin increased markedly. After 7 days' induction, NSE and GFAP-positive cells increased significantly. Furthermore, the addition of bFGF and GM1 caused the maximal variation. However, addition of GM1 alone had no inductive effects.

CONCLUSIONSCombination of bFGF with GM1 may synergistically promote the transformation of MSCs and differentiation into neurons and astrocyte-like cells. The results suggest a promising route for the application of MSCs.

Analysis of Variance ; Animals ; Bone Marrow Cells ; Cell Differentiation ; drug effects ; physiology ; Cells, Cultured ; Drug Synergism ; Fibroblast Growth Factor 2 ; pharmacology ; Fluorescent Antibody Technique ; G(M1) Ganglioside ; pharmacology ; Immunohistochemistry ; Probability ; Rats ; Rats, Wistar ; Sensitivity and Specificity ; Stem Cells ; pathology ; physiology ; Stromal Cells ; drug effects ; physiology ; ultrastructure

OBJECTIVETo determine the protective effect of monosialoganglionside (GM1) and evaluate the influence of GM1 on expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in Sprague-Dawley (SD) rats with focal cerebral ischemia-reperfusion (I/R).

METHODSLeft middle cerebral artery (MCA) was occluded by an intraluminal suture for 1 h and the brain was reperfused for 72 h in SD rats when infarct volume was measured, GM1 (10 mg/kg) was given ip (intraperitoneally) at 5 min (group A), 1 h (group B) and 2 h (group C) after MCA occlusion (MCAo). Expression of NMDAR1 was detected by Western blot at various time after reperfusion (4 h, 6 h, 24 h, 48 h and 72 h) in ischemic hemispheres of the rats with or without GM1 administered.

RESULTS(1) Adjusted relative infarct volumes of groups A and B were significantly smaller than that of group C and the control group (P<0.01 and P<0.05, respectively). (2) Expression level of NMDAR1 was temporally high at 6 h after reperfusion, and dipped below the normal level at 72 h after reperfusion. GM1 at 5 min after MCAo significantly suppressed the expression of NMDAR1 at 6 h after reperfusion (P<0.05 vs the control). At 72 h after reperfusion, the NMDAR1 expression level of rats treated with GM1 administered (at 5 min or 2 h after MCAo) was significantly higher than that of the control (P<0.05).

CONCLUSIONGM1 can time-dependently reduce infarct volume in rats with focal cerebral I/R partly through stabilizing the expression of NMDAR1.

Animals ; Brain Ischemia ; metabolism ; pathology ; prevention & control ; G(M1) Ganglioside ; pharmacology ; therapeutic use ; Gene Expression Regulation ; drug effects ; Male ; Middle Cerebral Artery ; surgery ; Neurons ; drug effects ; physiology ; Protein Subunits ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; metabolism ; Reperfusion Injury ; metabolism ; pathology ; prevention & control ; Treatment Outcome