Enzyme-linked immunosorbent assay (ELISA) for antibodies to human myelin and axolemma-enriched fractions

Antibodies to the axolemma-enriched fraction in the cerebrospinal fluid and serum of patients with multiple sclerosis and other neurological diseases

Antibodies to an axolemma-enriched fraction (AEF) antigen have been detected in the cerebrospinal fluid (CSF) and serum of patients with Multiple Sclerosis (MS) using an enzyme-linked immunosorbent assay (ELISA). A marginal elevation (P < 0.08) of anti-AEF IgG was found in MS CSF when compared with OND samples. When CSF was diluted to a standardized IgG concentration, the anti-AEF IgG level in MS CSF was significantly elevated (P=0.007) when compared to OND CSF. MS serum was also found to contain a significantly higher level (P < 0.001) of anti-AEF IgG when compared to OND serum using the ELISA technique.

Serum IgG antibody to herpes viruses in schizophrenia

Immunoglobulin measurements have provided indirect evidence to suggest that viruses may play an etiologic role in schizophrenia. The authors review the conflicting studies and report their own measurements of serum antibody absorbance to five viral antigens using an ELISA technique in 38 schizophrenic patients and 22 matched controls. For herpes simplex virus, 12 subjects (32%) had antibody levels more than 2 SD above the control mean.

Isolation and characterization of axolemma-enriched fractions from discrete areas of bovine CNS

Myelinated axons were isolated by flotation from bovine pons, middle cerebellar peduncle, cervical spinal cord and three regions of the subcortical white matter. The myelinated axons were osmotically and mechanically shocked, followed by fractionation on a linear 15% sucrose to 45% sucrose density gradient. Axolemma-enriched fractions (AEF) found in the 28% to 32% sucrose region of the gradient from brainstem and cord white matter had high acetylcholinesterase (AChE) while little or nil AChE activity was found in corresponding AEF derived from the subcortical white matter. Morphologically, the subcortical white matter from all regions contained a heterogeneous population of well-myelinated to thinly myelinated axons, while brainstem and cord regions contained a more homogeneous population of well-myelinated axons. Histochemical analysis of AChE localized this enzyme to axonal elements. The AEF derived from any white matter source had similar polypeptide compositions. AEF derived from subcortical white matter contained two-fold more myelin basic protein and a three-fold greater content of 2' 3' cyclic nucleotide 3' phosphodiesterase (CNP) compared with AEF derived from well myelinated white matter. We conclude that the purity of the AEF is related to the degree of myelination of the white matter from which the AEF is derived. Homogeneously well myelinated white matter (pons, cerebellar peduncle, cervical spinal cord) yields the highest purity AEF, as judged by the low CNP and myelin basic protein content and highest enrichment in AChE specific activity.

Linear response curves from an ELISA assay: measurement of anti-myelin IgG and IgM during experimental allergic neuritis

An ELISA method for generating linear dose-response curves for measuring anti-myelin IgG and IgM is described. Linearity is achieved without logarithmic transformations. This test is used to measure plasma levels of anti-myelin antibodies in rabbits with EAN. Results are expressed as relative concentrations of antibody in arbitary mass units with 95% confidence limits fitted by inverse prediction. In the 8 animals studied, appearance of anti-myelin antibody always preceded onset of clinical signs and neither anti-myelin IgG nor IgM could be detected in any animal pre-inoculation. Five out of 8 animals displayed steady and progressive increases in anti-myelin IgG with the remaining 3 animals showing plateaus in IgG levels 21-30 days post-inoculation. Increases in anti-myelin IgG were generally parallelled by increases in disease severity. However, 2 animals showed recovery and relapse from EAN with no change in plasma levels of anti-myelin IgG. Patterns of production of anti-myelin IgM varied with some animals displaying early peaks while others showed gradual increases.

Anti-myelin antibodies in cerebrospinal fluid and serum of patients with meningopolyneuritis Garin-Bujadoux-Bannwarth and other neurological diseases

Anti-myelin antibodies (AMA) of IgG, IgM, and IgA class were investigated by ELISA in CSF and serum from patients with meningopolyneuritis Garin-Bujadoux-Bannwarth (GBB), other inflammatory diseases of the nervous system (ID) comprising meningoencephalitis (ME), multiple sclerosis (MS), and Guillain-Barré syndrome (GBS), and various noninflammatory neurological diseases (NID). Anti-Borrelia antibodies (ABA) were determined by ELISA in GBB patients. In CSF, a high incidence of IgG-AMA, IgM-AMA, and IgA-AMA was found in GBB as compared with ID and NID. On average, positive AMA titers were higher in GBB than in ID and NID, IgM-AMA titers in GBB being most prominent. In serum, AMA were found in all but 2 patients investigated. On average, IgM-AMA titers were higher in GBB and MS than in other diseases; IgG-AMA titers in GBB and ME were relatively low. Antibody indices, calculated from titer values and Ig concentrations in CSF and serum, indicate intrathecal synthesis mainly of IgG- and IgA-AMA, and of IgG- and IgM-ABA. Participation of AMA in the pathogenesis of GBB may be envisaged, but needs further confirmation.

Characterization of an antiserum against an axolemma-enriched fraction

An antiserum was raised to rat central nervous system (CNS) axolemma-enriched fractions (AEF), which showed no cross-reactivity with myelin proteins or liver microsomes yet gave an endpoint titer of 1:51 200 to CNS AEF by the enzyme-linked immunosorbent assay (ELISA). Immunochemical staining of electroblotted proteins from rat CNS and peripheral nervous system (PNS) AEFs separated by gel electrophoresis identified a major reactive band at 38.5 kD. CNS AEF also showed major immunoreactivity at 91 kD (+/- 3 kD) and a broad band from 110 kD to 130 kD. By immunoperoxidase staining the antiserum specifically recognized the axolemma of peripheral nerve and synaptic terminals in the CNS. The significance of the specificity is discussed with respect to anti-synaptosome antisera.

A micromethod for absorption of specific antibody using an enzyme-linked immunosorbent assay (ELISA)

A procedure for absorbing specific antibodies using an enzyme-linked immunosorbent assay system (ELISA) has been developed. This is accomplished by serial absorption of the serum using less than 20 micrograms antigen. The sera can then be used in an ELISA system to test reactivity with other antigens. The system was tested by absorbing anti-myelin or anti-cerebroside antibodies and comparing these results with bulk absorption.