Abstract
Interleukin-11, a cytokine with multiple biological activities, has been shown to stimulate the proliferation and to support the long-term growth of human myeloma cell lines. Despite this, no expression of the interleukin-11α receptor has so far been demonstrated in myeloma cells. We have investigated the expression of interleukin-11α receptor and interleukin-11 at the level of mRNA and protein product in bone marrow mononuclear cells isolated from patients with multiple myeloma using reverse-transcriptase polymerase chain reaction and flow cytometry. The mRNA for interleukin-11α receptor and/or the corresponding protein were identified in 9 of 15 patients with multiple myeloma. In contrast, the interleukin-11 was not detected in any of the patients examined.