Lokhorst H M, Lamme T, de Smet M, Klein S, de Weger R A, van Oers R, Bloem A C
Department of Hematology, University Hospital Utrecht, The Netherlands.
Blood. 1994 Oct 1;84(7):2269-77.
Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA-5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.
对来自多发性骨髓瘤（MM）患者和正常供体的长期骨髓培养物（LTBMC）进行免疫表型和细胞因子产生分析。骨髓瘤来源和正常供体来源的LTBMC贴壁细胞均表达CD10、CD13、黏附分子CD44、CD54、血管细胞黏附分子1、极晚期抗原2（VLA - 2）和VLA - 5，并且细胞外基质成分纤连蛋白、层粘连蛋白以及3型和4型胶原呈阳性。骨髓瘤患者和正常供体的LTBMC自发分泌白细胞介素 - 6（IL - 6）。然而，IL - 6水平与疾病分期相关；在活动性骨髓瘤患者的LTBMC中发现IL - 6水平最高。为了确定IL - 6产生的来源，将MM患者和正常供体的LTBMC与骨髓来源的骨髓瘤细胞及骨髓瘤细胞系的细胞进行共培养。IL - 6由黏附于LTBMC的浆细胞系如ARH - 77和RPMI - 8226诱导产生，但非黏附细胞系U266和FRAVEL则不能诱导。骨髓瘤细胞在与正常供体和骨髓瘤患者的LTBMC贴壁细胞共培养时强烈刺激IL - 6分泌。当通过组织培养插入物阻止LTBMC与浆细胞之间的直接细胞接触时，未诱导出IL - 6产生。这意味着紧密的细胞间接触是IL - 6诱导的先决条件。纯化的骨髓瘤细胞与LTBMC贴壁细胞的结合部分被针对浆细胞上的黏附分子VLA - 4、CD44和淋巴细胞功能相关抗原1（LFA - 1）的单克隆抗体抑制。针对VLA - 4、CD29和LFA - 1的抗体也抑制了浆细胞 - LTBMC共培养中诱导的IL - 6分泌。与浆细胞共培养前后进行的原位杂交研究表明LTBMC贴壁细胞产生IL - 6。这些结果表明，在活动性疾病的MM患者的LTBMC中发现的高水平IL - 6反映了它们先前在体内与肿瘤细胞的接触。这些结果为MM中的肿瘤生长提供了新的视角，并强调了浆细胞 - LTBMC相互作用在MM病理生理学中的重要性。
