Interleukin 6

Clinical Significance:
The Interleukins belong to the family termed cytokines.  They are peptides used by immune and inflammatory cells to communicate and control cell operations. The cytokines have some similar actions to the Growth Factors but Growth Factors regulate proliferation of non-immune cells.  Interleukin 6 is a 25,000 molecular weight glycoprotein produced primarily in macrophages, T cells, fibroblasts and endothelial cells.  Its primary target cells are T and B cells and neutrophils.  Its main actions are involvement in terminal differentiation of B cells to antibody secreting plasma cells, activation of T cells and stimulation of hepatocyte production of acute phase proteins.  Interleukin stimulates Prolactin, Growth Hormone, Luteinizing Hormone, Follicle Stimulating Hormone and ACTH.  Release is stimulated by Interleukin 1a and b, Vasoactive Intestinal Polypeptide, and Prostaglandin E2.  Release is not affected by aspirin or indomethacin.  Levels are elevated in multiple myeloma, rheumatoid arthritis, systemic lupus erythematosus, meningococcus meningitis and infectious peritonitis.

Reference Range:
Reference Range available by report.

Interleukin 6 is measured by direct enzyme immunoassay.

Patient Preparation:
Patient should not be on any Corticosteroids, anti-inflammatory medications or pain killers, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Freeze specimen immediately after separation.  Minimum specimen size is 1 ml.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens frozen in dry ice.

1. JT Whicher and SW Evans.  Cytokines in Disease.  Clinical Chemistry 36: 1269-1281, 1990.

2. BL Spangelo, WD Jarvis, AM Judd, and RM MacLeod.  Induction of Interleukin-6 Release by Interleukin-1 in Rat Anterior Pituitary Cells in vitro:  Evidence for an Eicosanoid Dependent Mechanism.  Endocrinology 129: 2886-2894, 1991.