title: Increased interleukin-6 mRNA expression in blood and cerebrospinal fluid mononuclear cells in multiple sclerosis.
abstract: The increased intrathecal production of immunoglobulins within the cerebrospinal fluid (CSF) compartment commonly observed in multiple sclerosis (MS) implicates participation of B cell activating factors. One effect of the cytokine interleukin (IL)-6 is induction of immunoglobulin production by activated B cells. Employing in situ hybridization (ISH) with synthetic oligonucleotide probes, we measured numbers of IL-6 mRNA-expressing mononuclear cells (MNC) in blood and CSF from patients with MS, aseptic meningo-encephalitis (AM), and in blood from patients with other neurological diseases (OND) and healthy subjects. Numbers of IL-6 mRNA-expressing MNC were elevated in blood (mean frequency 1 per 33,000 MNC) and even further enriched in the CSF (1 per 10,000 MNC) of MS patients, and to a similar extent in AM patients' blood. Cultivation in the presence of myelin basic protein and proteolipid protein revealed strong augmentation of IL-6 mRNA-positive cells in MS but not in OND. The results suggest that IL-6 is one of several cytokines which are upregulated in MS, in particular locally in the CSF. A role of IL-6 in MS, whether disease- promoting or protective, remains unclear.
authors.affiliation: Division of Neurology, Karolinska Institute, Huddinge Hospital, Stockholm, Sweden.
authors.forename: V
authors.initials: V
authors.lastname: Navikas
authors.forename: D
authors.initials: D
authors.lastname: Matusevicius
authors.forename: M
authors.initials: M
authors.lastname: Söderström
authors.forename: S
authors.initials: S
authors.lastname: Fredrikson
authors.forename: P
authors.initials: P
authors.lastname: Kivisäkk
authors.forename: A
authors.initials: A
authors.lastname: Ljungdahl
authors.forename: B
authors.initials: B
authors.lastname: Höjeberg
authors.forename: H
authors.initials: H
authors.lastname: Link
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002555:Cerebrospinal Fluid / Q000166:cytology / Q000378:metabolism; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis*
chemical_list: D015850:Interleukin-6; D012333:RNA, Messenger