Tsertsvadze T, Mitskevich N, Bilanishvili A, Girdaladze D, Porakishvili N
Iv. Javakhishvili Tbilisi State University; Institute of Haematology and Blood Transfusiology, Tbilisi, Georgia; University of Westminster, London, UK.
Georgian Med News. 2017 Sep(270):88-93.
Chronic lymphocytic leukaemia (CLL) is a lymphoproliferative disease characterised by accumulation of monoclonal CD19+CD5+CD23+ lymphocytes in the peripheral blood and bone marrow. CLL is the most common type of the adult leukemia in the Western world. The disease is incurable, albeit there are new molecular and immunotherapy methods currently available in conjunction with chemotherapy, leading to the "precision therapy". The majority of immunotherapeutic approaches are based on the ability of therapeutic antibodies (Rituximab, Alemtuzumab) to mobilize anti-tumour potential of the Natural Killer cells and macrophages/monocytes through their Fcg-receptors (FcγR). Therefore functional status of monocytes in CLL is an important contributor to the efficacy of this treatment. In addition, CLL patients are characterized by a profound immunodeficiency, and how this affects monocytes, has not been established. Here we study ex vivo phagocytic function and the expression of Fcg receptors and CD180 toll-like receptor (TLR) by monocytes of 14 untreated and 8 treated with Cyclophosmamide, Adriamycin, Prednisolone (COP) CLL patients, and 12 age-matched control volunteers. Phagocytic function was assessed through the ability of freshly isolated monocytes to attach and to engulf intact or opsonized Staphylococcus aureus particles in vitro with or without Granulocyte/Macrophage Colony Stimulating Factor (GM-CSF) and Interferon g (IFNg). Simultaneously, immunophenotyping for FcγRI (CD64), FcγRII (CD32), FcγRIII (CD16) and CD180 has been carried out. The results were assessed by Flow Cytometry. Our results demonstrated that phagocytosis of the intact and opsonised or intact S. aureus by monocytes of CLL patients was significantly decreased in comparison with normal controls, with no recovery upon the treatment with GM-CSF and IFNg. A significant decrease in the expression of CD64 and CD180 has been detected on monocytes of CLL patients, with the drop in CD64 expression correlating with the disease progression and advanced Rai stages. In addition, the treatment with COP led to a more profound decrease in the expression of CD64. No appreciable changes were detected in the expression of CD32 and CD16 throughout the experiments. The diminished expression of CD64 and CD180 provides possible explanation for the impaired phagocytic function of monocytes in CLL, as FcγRI receptor interaction with opsonising IgG1, and CD180 with the ligands on S. aureus might affect the ability of monocytes to attach and to engulf S. aureus particles and effectively eliminate the pathogen. Our data indicates that the decreased functional status of monocytes in CLL might contribute to the diminished efficacy of therapeutic antibodies as well as to the immunodeficiency, characteristic for these patients.
慢性淋巴细胞白血病（CLL）是一种淋巴细胞增殖性疾病，其特征是外周血和骨髓中出现单克隆CD19 + CD5 + CD23 +淋巴细胞积聚。CLL是西方世界最常见的成人白血病类型。尽管目前有新的分子和免疫疗法与化疗联合应用，带来了“精准治疗”，但该疾病仍无法治愈。大多数免疫治疗方法基于治疗性抗体（利妥昔单抗、阿仑单抗）通过其Fcg受体（FcγR）调动自然杀伤细胞和巨噬细胞/单核细胞抗肿瘤潜力的能力。因此，CLL中单核细胞的功能状态是这种治疗疗效的重要影响因素。此外，CLL患者具有严重的免疫缺陷，而这如何影响单核细胞尚未明确。在此，我们研究了14例未经治疗以及8例接受环磷酰胺、阿霉素、泼尼松（COP）治疗的CLL患者和12名年龄匹配的对照志愿者的单核细胞的体外吞噬功能以及Fcg受体和CD180 Toll样受体（TLR）的表达。通过新鲜分离的单核细胞在体外附着并吞噬完整或调理的金黄色葡萄球菌颗粒的能力来评估吞噬功能，实验中添加或不添加粒细胞/巨噬细胞集落刺激因子（GM - CSF）和干扰素γ（IFNg）。同时，对FcγRI（CD64）、FcγRII（CD32）、FcγRIII（CD16）和CD180进行免疫表型分析。结果通过流式细胞术进行评估。我们的结果表明，与正常对照相比，CLL患者单核细胞对完整和调理或完整金黄色葡萄球菌的吞噬作用显著降低，用GM - CSF和IFNg治疗后未恢复。在CLL患者的单核细胞上检测到CD64和CD180表达显著降低，CD64表达的下降与疾病进展和晚期Rai分期相关。此外，COP治疗导致CD64表达进一步显著降低。在整个实验过程中，未检测到CD32和CD16表达有明显变化。CD64和CD180表达的降低可能解释了CLL中单核细胞吞噬功能受损的原因，因为FcγRI受体与调理的IgG1相互作用，以及CD180与金黄色葡萄球菌上的配体相互作用，可能影响单核细胞附着和吞噬金黄色葡萄球菌颗粒并有效清除病原体的能力。我们的数据表明，CLL中单核细胞功能状态的降低可能导致治疗性抗体疗效降低以及这些患者特有的免疫缺陷。
