Introduction:
Interleukin 6, together with IL-4, IL-5, IL-9 and IL-10 is produced by Th2 cells and is involved in antibody production, as well as protective responses to parasites and allergens (1). IL-6 may also be produced by monocytes and macrophages in response to bacterial infection. An increased serum level of IL-6 is found in an hepatic acute-phase response, and correlates with mortality in patients with sepsis (2). IL-6 may also be produced by fibroblasts, B cells, endothelial cells and several tumor cells.
IL-6 may be both a growth factor and differentiation factor for B cells. IL-6 is a potent myeloma cell growth factor for patients with multiple myeloma (MM), allowing the generation of myeloma cell lines whose proliferation is completely dependent on exogenous IL-6 (3,4).

Application:
IL-6, clone B-E8, is used to detect intracellular IL-6 in human leukocytes, fibroblasts and endothelial cells by flow cytometry or by immunohistochemistry on cytospots (frozen tissue sections is being checked). Clone B-E8 is also suitable for biological studies.
IL-6 mRNA has been demonstrated in bone marrow monocytes and myeloid cells of most myeloma patients but not in purified myeloma cells demonstrating the paracrine origin of IL-6 in multiple myeloma (5). Increasing evidence suggests a predominantly anti-inflammatory and immunosuppressive role for IL-6 and some of the IL-6 regulated acute phase proteins (6).

Specifications:
Anti-IL-6, clone B-E8, is a murine IgG1 monoclonal antibody specific for a 20 - 30 kD cytoplasmic antigen, human IL-6. Clone B-E8 recognizes both natural and recombinant human IL-6 (7,8) and blocks IL-6 induced proliferation on a B9 cell line. It is generally advisable to use a specificity control such as one of the following: 1) unlabelled antibody, 2) recombinant cytokines or 3) mouse isotype control.

Literature references:

1. Garside,P., Mowat,A.McI., 1995. Immunology Today 16; 220
2. Friedland, J.S., et al 1992. Infect. Immun 60: 2402
3. Kawano, M., 1988. Nature. 332: 83
4. Shimizu,S., et al., 1989. J.Exp. Med. 169: 339
5. Portier,M., et al. 1991. Eur.J.Immunol. 21: 1759
6. Tilg,H., et al., Immunology Today. 18: 428-432
7. Wijdenes,J., et al 1991. Mol Immunol. 28: 1183-1192
8. Wijdenes et al. 1995. Eur. J. Immunol. 25: 3474 -3481