Stein G M, Berg P A
Department of Internal Medicine, University of Tübingen, Germany.
Anticancer Drugs. 1997 Apr;8 Suppl 1:S39-42. doi: 10.1097/00001813-199704001-00009.
Cytotoxic as well as immunomodulatory effects of mistletoe extracts and their components have been described and seem to depend upon the host tree, the manufacturing process and the composition of the different components present in the extracts. In vitro studies showed that a fermented mistletoe extract derived from Viscum album L. grown on pine trees was less cytotoxic to peripheral blood mononuclear cells (PBMC) than other preparations. This finding could be related to its very low content of mistletoe lectins. Furthermore, this extract stimulated PBMC from healthy and especially allergic donors who had never received any mistletoe treatment. By analysing these in vitro reactions, an involvement of CD4+ T helper cells and CD14+ monocytes/macrophages was observed, suggesting an interaction of the specific and nonspecific immune system. In the supernatants of stimulated PBMC from healthy individuals, type-1 (interferon-gamma and interleukin-2) and type-2 (interleukin-4 and interleukin-5) associated cytokines were detected in about 20%. In patients with colorectal tumours, however, reduced frequency, suggesting a functional impairment of certain immunocompetent cells in these patients. These studies may help to evaluate properties of the natural and the specific immune system.
槲寄生提取物及其成分的细胞毒性和免疫调节作用已被描述，其似乎取决于宿主树、制造工艺以及提取物中不同成分的组成。体外研究表明，源自生长在松树上的欧洲槲寄生的发酵槲寄生提取物对外周血单核细胞（PBMC）的细胞毒性低于其他制剂。这一发现可能与其极低的槲寄生凝集素含量有关。此外，该提取物刺激了从未接受过任何槲寄生治疗的健康尤其是过敏供体的PBMC。通过分析这些体外反应，观察到CD4 + T辅助细胞和CD14 +单核细胞/巨噬细胞的参与，提示特异性和非特异性免疫系统之间存在相互作用。在健康个体受刺激的PBMC上清液中，约20%检测到1型（干扰素-γ和白细胞介素-2）和2型（白细胞介素-4和白细胞介素-5）相关细胞因子。然而，在结直肠肿瘤患者中，其频率降低，提示这些患者某些免疫活性细胞存在功能损害。这些研究可能有助于评估天然和特异性免疫系统的特性。
