Increased interleukin-6 mRNA expression in blood and cerebrospinal fluid mononuclear cells in multiple sclerosis

• Published in: Journal of neuroimmunology Vol. 64; no. 1; pp. 63 - 69
• Main Authors: Navikas, V., Matusevicius, D., Söderström, M., Fredrikson, S., Kivisäkk, Pia, Ljungdahl, Å., Höjeberg, B., Link, H.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 1996
• Subjects: Adult; Aged; Aged, 80 and over; Autoimmunity; Cerebrospinal fluid; Cerebrospinal Fluid - cytology; Cerebrospinal Fluid - metabolism; Cytokines; Female; Humans; Interleukin-6; Interleukin-6 - genetics; Leukocytes, Mononuclear - metabolism; Male; Medicin och hälsovetenskap; Middle Aged; Multiple sclerosis; Multiple Sclerosis - metabolism; RNA, Messenger - analysis; Autoimmunity; Multiple sclerosis; Cerebrospinal fluid; Cytokines; Interleukin-6
• ISSN: 0165-5728; 1872-8421
• DOI: 10.1016/0165-5728(95)00155-7

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 33000 MNC) and even further enriched in the CSF (1 per 10000 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.