Kumar S, Rajkumar S V, Kimlinger T, Greipp P R, Witzig T E
Division of Hematology, Department of Internal Medicine, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
Leukemia. 2005 Aug;19(8):1466-70. doi: 10.1038/sj.leu.2403823.
Multiple myeloma (MM) is characterized by accumulation of clonal plasma cells (PCs). CD45, a key regulator of antigen-mediated signaling and activation in lymphocytes, is present in early stages of PCs development. We studied CD45 expression on MM PCs by flow cytometry, correlating it to important biological disease characteristics. Additionally, we examined the expression of various adhesion molecules on PCs. A total of 75 patients with untreated MM (29), relapsed MM (17), smoldering MM (12), and monoclonal gammopathy of undetermined significance (MGUS) (17) were studied. The proportion of PCs expressing CD45 was higher among those with early disease (MGUS or smoldering MM) compared to those with advanced disease (new or relapsed MM) (43 vs 22%; P=0.005). Among those with advanced disease, patients with bone lesions had a lower percentage of CD45-positive (CD45+) PCs; 14 vs 34% (P=0.02). Patients with high-grade angiogenesis had a lower percentage of CD45+ PCs; 13 vs 31% (P=0.03). The median overall survival for the CD45+ group (>20% PCs positive) was 39 vs 18 months for the CD45-negative (CD45-) group (P=0.07). The expression of CD138, CD56 and CD54 were higher among the CD45- PCs. This study demonstrates important biological correlates of CD45 expression on myeloma cells.
多发性骨髓瘤（MM）的特征是克隆性浆细胞（PCs）的积累。CD45是淋巴细胞中抗原介导信号传导和激活的关键调节因子，存在于PCs发育的早期阶段。我们通过流式细胞术研究了MM PCs上CD45的表达，并将其与重要的生物学疾病特征相关联。此外，我们还检测了PCs上各种黏附分子的表达。共研究了75例未经治疗的MM患者（29例）、复发MM患者（17例）、冒烟型MM患者（12例）和意义未明的单克隆丙种球蛋白病（MGUS）患者（17例）。与晚期疾病（新发或复发MM）患者相比，早期疾病（MGUS或冒烟型MM）患者中表达CD45的PCs比例更高（43%对22%；P=0.005）。在晚期疾病患者中，有骨病变的患者CD45阳性（CD45+）PCs的百分比更低；14%对34%（P=0.02）。高等级血管生成的患者CD45+ PCs的百分比更低；13%对31%（P=0.03）。CD45+组（>20%的PCs阳性）患者的中位总生存期为39个月，而CD45阴性（CD45-）组为18个月（P=0.07）。CD45- PCs中CD138、CD56和CD54的表达更高。本研究证明了骨髓瘤细胞上CD45表达的重要生物学相关性。
