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PubMed · 2838999

Studies on activation variables in multiple sclerosis.

Abstract

The study aimed to evaluate the usefulness of some selected immune variables as markers of disease activation, progression and possible etiopathogenesis of multiple sclerosis (MS). Levels of neopterin, a factor known to be released from macrophages and monocytes at increased rates in cellular immune reactions were higher in cerebrospinal fluid (CSF) from patients with MS during exacerbations in comparison with remissions. The elevation in CSF during exacerbations was not reflected in serum. Expression of HLA class II antigens (DR) on activated T lymphocytes in CSF were encountered at elevated percentage in only 10% of patients with MS, against 81% of patients with acute aseptic meningoencephalitis (AM). In patients with AM, the DR expression on CSF T cells was found on both CD8+ and CD4+ cells. There was no correlation between percentage of DR+ T cells in CSF and disability, exacerbation/remission or recent onset of disease in patients with MS. Phenotypic characterization of mononuclear cells in CSF and peripheral blood revealed increased proportion of CD5+ cells in CSF compared to peripheral blood which in MS was not reflected by any changes in CD4+ or CD8+ cells, while in AM the increase of CD5+ cells in CSF was followed by increase of CD4+ cells. A population of CD5+, CD8-, CD4- cells might be postulated to occur in MS CSF. Levels of CD8+ cells in peripheral blood and CSF did not fluctuate in parallel with disease activity as measured as clinical exacerbation. OKB7+, OKM1+ and HLA-DR+ cells differed significantly between CSF and peripheral blood, indicative of a selective passage of cells into the central nervous system (CNS) - CSF compartment. Proliferating cells expressing transferrin receptors (OKT9) were generally few or absent in CSF of patients with MS. MS patients' bone marrow mononuclear cells showed higher spontaneous proliferation both in comparison with cells from bone marrow of control subjects and peripheral blood lymphocytes from MS patients. PHA response of bone marrow mononuclear cells from MS patients was also higher than that from controls. There was, however, no significant difference in proliferative response of peripheral blood lymphocytes between MS patients and controls. Seven of 11 MS patients showed morphological signs of activation in their bone marrow, without correlation to patients' clinical condition. Higher levels of undifferentiated or activated cells, measured as OKT10+ cells were found in peripheral blood of patients with MS compared to controls.(ABSTRACT TRUNCATED AT 400 WORDS)

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BibTeXRIS

S Fredrikson. 1988. Studies on activation variables in multiple sclerosis.. https://pubmed.ncbi.nlm.nih.gov/2838999/

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GTP cyclohydrolase feedback regulatory protein controls cofactor 6-tetrahydrobiopterin synthesis in the cytosol and in the nucleus of epidermal keratinocytes and melanocytes.

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