Deregulation of the expression of these interleukins was shown to be responsible for various diseases, such as i) IL-4 vs. immediate type hypersensitivity and ii) IL-6 vs. autoimmunity and multiple myelomas.
Glucocorticoids significantly inhibited proliferation of myeloma cells, and decreased the messenger RNA (mRNA) expressions of interleukin-6 (IL-6) and secretory type immunoglobulin G (IgG).
However, the hepatoma line PLC/PRF/5, which contains 2,300 IL6 receptors, was more sensitive to IL6-PE40 (amount of protein required to inhibit protein synthesis by 50% was 5 ng/ml) than both the myeloma cell lines U266 and H929 (for both cell lines, the 50% inhibitory dose was 8 ng/ml), which contain 15,500 and 16,500 IL6 receptors, respectively.
Northern blot analysis revealed that the growth inhibition of the IL-6-dependent MM cell line U-1958 was not due to down-regulation of IL-6 receptor mRNA expression and that the differential sensitivity to IFN-gamma was not due to differences in IFN-gamma receptor expression.
A definitive separation of both putative sources for IL-6 may be difficult to achieve in fresh patient IL-6 growth requirement and production by pure myeloma cell populations using seven human myeloma cell lines (OCI-My 1 to 7) that were established from patients with advanced disease.
The establishment of an interleukin-6-dependent myeloma cell line (FLAM-76) carrying t(11;14)(q13;q32) chromosome abnormality from an aggressive nonsecretory plasma cell leukemia.
To determine whether the receptor for IL-6 may exist as a soluble molecule, RNA was analysed from the transformed B-cell lines U266, CESS and Daudi, from bone marrow from two myeloma patients, and from normal leukocytes.
In the present study, we devised a model of IL-6 autocrine growth in vitro by transfecting IL-6 cDNA into a human myeloma cell line that had a proliferative response to IL-6 but did not produce IL-6.
The direct effect of IL-6 on IL-6 receptor gene expression in myeloma cells was further confirmed by adding IL-6 to an autonomously growing myeloma cell line.
A human multiple myeloma (MM) cell line, U-266, has developed the ability to grow independently of exogenous interleukin 6 (IL-6) during long-term cultivation in vitro.
Abnormal expression of the IL-6 gene has been suggested to be involved in the pathogenesis of a variety of diseases, especially rheumatoid arthritis, Castleman's disease, mesangial proliferative glomerulonephritis, multiple myeloma and Kaposi's sarcoma.
These results suggest that, among cytokines shown to control myeloma-cell growth in vitro, IL-1, IL-6 and G-CSF could play a role in the development of myeloma disease in vivo.
gamma-Interferon in multiple myeloma: inhibition of interleukin-6 (IL-6)-dependent myeloma cell growth and downregulation of IL-6-receptor expression in vitro.
To investigate the source and target cells of IL-6 activity in multiple myeloma, expression of the cytokine and its receptor genes by myeloma plasma cells was studied.
Interleukin-6 (IL-6) is a differentiation and growth factor for a variety of cell types and its excessive production plays a major role in the pathogenesis of multiple myeloma and post-menopausal osteoporosis.
The pleiotropic cytokine interleukin 6 (IL-6) plays a role in the pathogenesis of various diseases, such as multiple myeloma, autoimmune and inflammatory diseases and osteoporosis.