Shahid Baig

Multiple Sclerosis: Cells Secreting Antibodies Against Myelin-Associated Glycoprotein are Present in Cerebrospinal Fluid

We evaluated the B‐cell response in cerebrospinal fluid (CSF) and blood by enumerating cells secreting antibodies to myelin‐associated glycoprotein (MAG) and, for reference, to myelin basic protein (MBP), two myelin components which may constitute targets for autoimmune attack in multiple sclerosis (MS). Among 25 untreated MS patients, 12 had cells in CSF secreting anti‐MAG IgG antibodies (mean value 1 per 1429 CSF cells) and three also had cells secreting anti‐MAG antibodies of the IgM Isotype but at lower levels. In CSF from 2 out of 10 MS patients examined, anti‐MAG and anti‐MBP IgG antibody‐secreting cells were present concurrently. Antibody‐secreting cells were less frequent in blood and bone marrow, reflecting compartmentalization to CSF. Anti‐MAG antibody‐secreting cells were found in CSF from only I out of 27 control patients. The intrathecal production of anti‐MAG and anti‐MBP antibodies may be important in the pathogenesis of MS.

B cells expressing CD5 are increased in cerebrospinal fluidof patients with multiple sclerosis

By two‐colour flow cytometric analysis, we found increased numbers of B cells co‐expressing the pan‐T cell marker CD5 and the B cell marker CD19 in cerebrospinal fluid (CSF) of 21 patients withmultiple sclerosis (MS), compared with 17 control subjects with muscular tension headache. Only onepatient with MS, but nine controls lacked CD5+ B cells in CSF. This difference was not observed inperipheral blood. Numbers of CD5+19+ B cells were increased in CSF compared with blood in MS, but not in the controls. In both groups, CD5+19+ B cells were not restricted to small restinglymphocytes, but were also found among larger‐sized lymphocytes. The relative density of CD5molecules and of CD19 molecules was lower in CD5+ 19+ thaninCD5‐ 19+ B cells and CD5+ 19‐ Tcells. CD5+ B cells are assumed to be responsible for auloanlibody production, and our resultssuggest a palhogenetic role of such cells, predominantly within the central nervous system, in MS.

PREDOMINANCE OF BORRELIA BURGDORFERI SPECIFIC B CELLS IN CEREBROSPINAL FLUID IN NEUROBORRELIOSIS

A nitrocellulose immunospot assay that allows the counting of cells secreting IgG, IgA, or IgM antibodies to Borrelia burgdorferi was used to compare B cell response to B burgdorferi at the cellular level in cerebrospinal fluid (CSF) and blood from patients with neuroborreliosis with that in patients with aseptic meningoencephalitis (AM) or non-inflammatory neurological diseases. 13 of the 14 patients with untreated neuroborreliosis had CSF cells secreting IgG antibodies to B burgdorferi (mean 17 cells per 10(4) CSF cells), whereas 8 of 12 patients examined had cells secreting IgA antibodies (mean 6 cells) and 10 of 12 had cells secreting IgM antibodies (mean 6 cells) per 10(4) CSF cells. IgG antibody producing cells predominated except in 2 patients with mainly or only IgM secreting cells. Cells secreting antibodies to B burgdorferi were rarely found in the blood and then at very low numbers, which reflects preferential compartmentalisation of the specific B cell response to the CSF. The cells were not detectable in CSF or blood from the two control groups. Evaluation of humoral immunity at the cellular level is a novel approach to the detection and localisation of immune events in neuroinflammatory disorders.

B cells and antibodies in MS

When the B-cell response was examined by enumeration of immunoglobulin (Ig)-secreting cells, normal cerebrospinal fluid (CSF)--in contrast to previous beliefs--contained IgG-secreting cells, indeed at an 8-fold higher proportion per 10(4) mononuclear cells (MNC) than blood. As expected, the proportion of IgG-producing cells was greatly increased in MS CSF. Evaluation of antibody (Ab) responses at the cellular level, thereby bypassing draw-backs inherent in determinations of circulating Ab levels, such as Ab binding to target, revealed that in one MS patient group, 57% had, in CSF, cells secreting IgG Ab against myelin basic protein (MBP) and, in another MS group, 55% had, in CSF, cells producing IgG Ab against myelin-associated glycoprotein (MAG); both MBP and MAG are possible targets for immune attack in MS. Anti-MBP and anti-MAG IgG antibody-secreting cells could occur in parallel or independently. They were rarely detected in blood, reflecting strong sequestration in CNS CSF. Their possible role in MS pathogenesis is envisaged in light of recently suggested coupling between polyclonal B-cell hyperresponsiveness and antigen-driven specific responses in autoimmune-prone individuals.

Distribution of plasma cells secreting antibodies against nervous tissue antigens during experimental allergic encephalomyelitis enumerated by a nitrocellulose immunospot assay

The B cell response to central nervous system (CNS) myelin and myelin basic protein, as well as total numbers of IgG secreting cells, was studied in acute experimental allergic encephalomyelitis using a nitrocellulose immunospot assay. The method was able to detect single plasma cells secreting antibodies. Cells secreting antibodies against myelin antigens were detected in regional lymph node cell suspension by day 5 post-immunization (p.i.). At that time no anti-myelin antibodies were detected free in serum. Later, at day 15 p.i., specific antibody secreting cells were found in bone marrow and spleen indicating a generalization of the immune response. The B cell response became partly sequestered to the target of immune attack since an increased number of IgG secreting cells was detected among mononuclear cells recovered from the CNS. Studies of cellular secretion of antibodies rather than free levels in body fluids may be a more accurate reflection of the in vivo B cell response. These findings may be generally considered in studies of B cell mediated immunity in neuroinflammatory diseases.

Coexistence of catecholamines and serotonin with substance P in cerebrospinal fluid of patients with multiple sclerosis or Parkinson's disease

In this study, the correlation between noradrenaline, dopamine, serotonin and substance P are studied in the cerebrospinal fluid from healthy subjects and patients with Parkinsons disease or multiple sclerosis. The results obtained showed linear relationships of substance P with the levels of noradrenaline, dopamine and serotonin in healthy subjects and all patient groups. The results can help in the understanding of cotransmission between amines and neuropeptide and the results could be taken into consideration prior to the designing of a therapeutic approach.

Neuropeptide Y, noradrenaline and their existence in cerebrospinal fluid of patients with ischemic brain stroke

In this study, the correlation between noradrenaline, and neuropeptide Y was studied in the cerebrospinal fluid from patients with ischemic brain stroke and healthy controls. The results obtained showed linear relationships of neuropeptide Y with the levels of noradrenaline, in healthy controls as well as in the patient group. The results can help in the understanding of cotransmission between amines and neuropeptide, and the results could be taken into consideration prior to the designing of a therapeutic approach.

Compartmentalization of B Cell Response to CSF in Lyme Disease with Neurological Manifestations

The Borrelia burgdorferi-specific B cell response in CSF and peripheral blood (PB) from patients with Lyme disease and neurological manifestations was studied with a nitrocellulose immunospot assay, enabling enumeration of cells secreting anti-Borrelia IgG, IgA and IGM antibodies. Such cells were found in CSF from most patients with neuroborreliosis, at mean values amounting to 32%, 40% and 34%, respectively, of IgG, IgA and IgM secreting cells in CSF. Anti-Borrelia antibody producing cells were only occasionally demonstrable in PB and then at very low numbers, reflecting a specific B cell response which is highly compartmentalized to CSF-CNS. Evaluation of B cell response at cellular level yields a different and more authentic picture of humoral immunity in comparison with conventional serology.

Nitrocellulose immunospot assay adopted to lyme disease: A new principle for evaluation of B cell response on the single cell level in CSF and blood

nant in the brain on day 7, while the spinal cord was the major site of MNL infiltration at a very late stage of infection (day 127). Both L3T4 + and Lyt2 + cells were found in a perivascular distribution while Lyt2 + cells infiltrated normal white matter. Therefore, L3T4 +, IgG +, and Mac-1 + cells appear to be important in the immune response during very early stages of infection, while Lyt2 + cells may be important effectors as demyelination progresses. Studies are underway to characterize MNL functionally in the CNS following TMEV infection.