ganglioside--gd1a and Nervous-System-Diseases

Two very high titer polyclonal antibodies against two ganglioside antigens, GM1 and GD1a, have been raised in New Zealand white rabbits using a homogeneous suspension of the highly purified antigens in Keyhole Limpet Hemocyanin and Freund's adjuvant. The antisera were prepared over a period of 6 months with repeated injections of the ganglioside suspension, followed by an intravenous injection of the purified ganglioside solution, and collecting the serum (approximately 50 ml) at defined time intervals. The GM1-antibody, thus prepared, showed a cross reactivity toward GDlb and asialo-GM1 (GA1), while the GDla-antibody reacted with GD1a, GM1 and GA1 and GD1b as determined by immuno-overlay and ELISA methods. The titer for GM1 antiserum, determined by'ELISA, was greater than 1/10,000 dilution while the titer for GD1a antibody was greater than 1/5000 dilution. No neurological or behavioral abnormality was observed during the period of antiserum production. To evaluate any likely pathological damage caused by such a high titer ganglioside-antibody, autopsy of CNS as well PNS tissues from the rabbits were carried out after the final bleeding. No obvious pathological changes, including demyelination, were noted in any of the four rabbits. These observations cast doubt as to the direct effect of anti-ganglioside antibody induced neurological and pathological disorders.

Topics: Animals; Antibodies; Cross Reactions; Enzyme-Linked Immunosorbent Assay; Freund's Adjuvant; G(M1) Ganglioside; Gangliosides; Hemocyanins; Immunohistochemistry; Nervous System Diseases; Rabbits

The occurrence and role of autoantibodies to gangliosides and other lipid-containing components of the central nervous system in Multiple Sclerosis (MS) are unsettled. Using sensitive ELISAs, we measured IgG and IgM antibody titers and absorbances to the three major gangliosides GD1a, GD1b and GM1, and to sulfatides, cardiolipin and myelin proteins in paired serum and cerebrospinal fluid (CSF) from patients with untreated MS, optic neuritis (ON), acute aseptic meningo-encephalitis (AM) and other neurological diseases (OND). Twenty-three per cent of 30 MS (P<0.04) and 18% of 32 ON patients (P<0.05) presented elevated IgG antibody titers to GD1a in serum compared to 9% of patients with OND. Six (40%) of the patients with malignant MS had elevated serum IgG antibody titers to GD1a compared to one (6%) of the patients with benign MS (P<0.04). In CSF, elevated IgG antibody titers to GD1a were measured in 13% of MS and 20% of ON patients compared to 4% of patients with OND (P<0. 03 and P<0.02, respectively). The augmented IgG response to GD1a in serum also separated MS from Guillain-Barré syndrome. Compared to OND increased IgM absorbances to sulfatides and cardiolipin were observed in CSF of patients with MS, but also in AM. Elevated IgG antibody titers to myelin proteins were found more often in MS patients' serum and MS, ON and AM patients' CSF compared to OND. The data implicate that among the multitude of enhanced B-cell responses occurring in MS and ON, that directed to GD1a is common and more discriminative, and should be evaluated in future MS treatment studies.

Topics: Adult; Antibodies, Anticardiolipin; Autoantibodies; B-Lymphocytes; Cerebrovascular Disorders; Female; G(M1) Ganglioside; Gangliosides; Humans; Immunoglobulin G; Immunoglobulin M; Male; Meningoencephalitis; Middle Aged; Multiple Sclerosis; Myelin Basic Protein; Nervous System Diseases; Optic Neuritis; Recurrence; Sulfoglycosphingolipids

IgM and IgG antibodies reacting with components of human brain gangliosides were detected in a patient bearing severe sensory ataxy. Using different chemical and immunological methods, the antigen was identified as the GD1a ganglioside. The antibodies showed antigen "density-dependent" binding, a property only observed in tumor-specific monoclonal antibodies. The relevance of this result in regard with target specificity of neuropathy-associated antibodies directed to ubiquitous glycolipids is discussed.

Topics: Antibody Specificity; Autoantibodies; Autoimmune Diseases; Gangliosides; Humans; Immunoglobulin A; Immunoglobulin G; Male; Middle Aged; Nervous System Diseases