Using Affymetrix microarrays, we identified the expression of the CD200 gene in multiple myeloma cells (MMC) of 112 patients with newly-diagnosed multiple myeloma (MM). The CD200 gene was either absent or present (Affymetrix call) in 22% and 78% of MMC, respectively. CD200 was not expressed by CD14 monocytes, CD15 polynuclear cells and CD3 T cells that were purified from the bone marrow of 5 newly-diagnosed patients. It is also not expressed in 7 osteoclast samples. BM stromal cells from 5 patients with MM expressed CD200, but at a 3.9 fold lower median signal compared to that in CD200present MMC (P = .04). CD200 is a membrane glycoprotein that imparts an immunoregulatory signal through CD200R, leading to the suppression of T-cell-mediated immune responses. Patients with CD200absent MMC have an increased event free survival (24 months) compared to patients with CD200present MMC (14 months), after high-dose therapy and stem cell transplantation. In a Cox-proportional-hazard model, the absence or presence of CD200 expression in MMC is predictive for EFS for patients independently of ISS stage or B2M serum levels. Thus, CD200 is an independent prognosis factor for patients with MM that could represent a new therapeutic target in MM.
Disclosure: No relevant conflicts of interest to declare.