Gruber G, Schwarzmeier J D, Shehata M, Hilgarth M, Berger R
Ludwig Boltzmann Institute for Cytokine Research and the Department of Internal Medicine I, Division of Hematology, University of Vienna Medical School, Vienna, Austria.
Blood. 1999 Aug 1;94(3):1077-85.
Several features are characteristic for hairy cell leukemia (HCL). Among those are pancytopenia, bone marrow fibrosis, and the appearance of a defined tumor cell phenotype in peripheral blood (PB), bone marrow (BM), and spleen. Hairy cells (HC) coexpress antigens specific for B lymphocytes and monocytes/macrophages and thus the malignant cell does not seem to be restricted to a defined lineage. When serum or bone marrow aspirate was screened by enzyme-linked immunosorbent assay (ELISA) for basic fibroblast growth factor (bFGF), specimen derived from HCL (serum: mean value, 29 pg/mL; BM aspirate: mean value, 641 pg/mL) contained significantly higher levels than those from healthy subjects. To study whether peripheral blood mononuclear cells (PBMC) derived from patients suffering from HCL and healthy donors (HD) were capable of producing bFGF, culture supernatant (conditioned medium, [CM]) was tested for the presence of this cytokine. While bFGF was not detectable in cell cultures from HD, HCL-derived CM contained relatively high levels of bFGF. CM was successfully used for stimulation of mesenchymal cell proliferation, which could be inhibited by a neutralizing anti-bFGF antibody. Cellular activation by pokeweed mitogen (PWM) or the combination of 12-o-tetradecanoyl-phorbol-13-acetate (TPA) plus calcium ionophore (Ca-Ip) led to an enhanced mRNA expression. Results of Western blot experiments showed that HC synthesize at least three isoforms (approximately 18, 23, and 25 kD), but only the 23-kD isoform is exported. To assess the nature of the producer cell, double immunofluorescence analysis using a bFGF-specific and an anti-CD11c monoclonal antibody (MoAb) was undertaken. The majority of cells scoring positive for CD11c were also reactive with the anti-bFGF MoAb. Furthermore, enrichment of CD19/CD11c-positive cells correlated with enhanced bFGF levels, thereby supporting the argument for HC being the producer cells of bFGF. A biological function of bFGF in HCL might be mediation of chemoresistance, as 2-chlorodeoxyadenosine (2-CdA)-induced inhibition of cell proliferation can be reversed by bFGF. Endogenous bFGF production by HC is not affected by this purine analogue and 2-CdA-induced apoptosis is diminished in bFGF-producing HC as compared with normal PBMC. Therefore, bFGF expression by HC might be important for resistance to chemotherapy and survival of the malignant cells.
毛细胞白血病（HCL）有几个特征性表现。其中包括全血细胞减少、骨髓纤维化，以及外周血（PB）、骨髓（BM）和脾脏中出现特定的肿瘤细胞表型。毛细胞（HC）共表达B淋巴细胞和单核细胞/巨噬细胞特异性抗原，因此恶性细胞似乎并不局限于某一特定谱系。当通过酶联免疫吸附测定（ELISA）检测血清或骨髓穿刺液中的碱性成纤维细胞生长因子（bFGF）时，来自HCL的标本（血清：平均值为29 pg/mL；骨髓穿刺液：平均值为641 pg/mL）中的含量明显高于健康受试者。为了研究来自HCL患者和健康供体（HD）的外周血单个核细胞（PBMC）是否能够产生bFGF，检测了培养上清液（条件培养基，[CM]）中这种细胞因子的存在情况。虽然在HD的细胞培养物中未检测到bFGF，但来自HCL的CM中含有相对较高水平的bFGF。CM成功用于刺激间充质细胞增殖，而这种增殖可被中和性抗bFGF抗体抑制。用商陆有丝分裂原（PWM）或12 - O - 十四烷酰佛波醇 - 13 - 乙酸酯（TPA）加钙离子载体（Ca - Ip）的组合进行细胞活化可导致mRNA表达增强。蛋白质印迹实验结果表明，HC至少合成三种异构体（约18、23和25 kD），但只有23 - kD的异构体被分泌。为了评估产生细胞的性质，进行了使用bFGF特异性抗体和抗CD11c单克隆抗体（MoAb）的双重免疫荧光分析。大多数CD11c呈阳性的细胞也与抗bFGF MoAb发生反应。此外，CD19/CD11c阳性细胞的富集与bFGF水平升高相关，从而支持HC是bFGF产生细胞的观点。bFGF在HCL中的生物学功能可能是介导化疗耐药性，因为bFGF可逆转2 - 氯脱氧腺苷（2 - CdA）诱导的细胞增殖抑制。HC产生内源性bFGF不受这种嘌呤类似物的影响，并且与正常PBMC相比，产生bFGF的HC中2 - CdA诱导的凋亡减少。因此，HC表达bFGF可能对化疗耐药性和恶性细胞的存活很重要。
