MOLECULAR ANALYSIS OF THE IL-6 RECEPTOR IN HUMAN MULTIPLE-MYELOMA, ANIL-6-RELATED DISEASE

A PCR-SSCP approach was used to search for mutations in IL-6 receptor genes in 9 human plasma cell lines (HMCL) and in tumor plasma cells fr om 19 patients with fulminating multiple myeloma, an IL-6-related dise ase. Whereas no mutation was found in the cytokine receptor homologous (CRH) domain of IL-6Ralpha, DNA and RNA polymorphisms in the gp130 CR H domain was detected in tumoral samples as well as in blood samples f rom healthy donors. Finally, mutations in the gp130 critical cytoplasm ic domain were found in one HMCL and in tumor plasma cells of one pati ent. Only the mutated allele was expressed in the HMCL.