1Iv. Javakhishvili Tbilisi State University, Division of Immunology and Microbiology; 2M. Zodelava Hematology Center,Tbilisi; 3Institute of Haematology and Blood Transfusiology, Tbilisi. Georgia.
2M. Zodelava Hematology Center,Tbilisi, Georgia.
Georgian Med News. 2020 Nov(308):118-123.
Chronic lymphocytic leukemia (CLL) is the most common adult leukaemia in the US and in Europe, including Georgia. CLL presents with clonal expansion and accumulation of CD5+CD19+CD23+ cells in peripheral lymphoid organs and tissues and in bone marrow. The disease remains incurable, albeit there are new molecular and immunotherapy methods currently available, which, in conjunction with chemotherapy, lead to the "precision therapy" approach. The majority of immunotherapies are based on the ability of therapeutic antibodies to mobilize anti-tumour potential of immune responses. Bispecific antibodies (BsAb) are also considered in the treatment of CLL, whereby phagocytic cells play a key effector role in the destruction of the target CLL cells. Anti-CD19/anti-CD64 BsAb binds to CD19 receptors on CLL cells and to CD64 receptors (FcγRI) on monocytes and activated polymorphonuclear neutrophils (PMNs), thus inducing phagocytosis of the leukaemic cells. The aim of this study was to evaluate the ability of anti-CD19/CD64 BsAb to enhance adherence of CLL cells by PMNs, intact or activated with G-CSF and IFNγ cytokines. Membranes of the isolated CLL cells of 16 patients were stained with Red Fluoresent Linker and CLL cells were co-incubated with isolated autologous PMNs, intact or pre-stimulated with G-CSF and/or IFNγ for 4h or 24h. The PMN/CLL cell adhesion was analyzed with the FACScan flow cytometer by gating on PMNs with adhered RFL-stained CLL cells. The results were heterogenous. Our data demonstrate that anti-CD19/anti-CD64 BsAb has limited capacity to enhance leukemic cell attachment by autologous PMNs. This could partially be explained by the remarkable intensity of spontaneous ability of PMNs to adhere to autologous CLL cells. Pre-treatment of PMNs from CLL patients with G-CSF and INFγ, alone or jointly did not enhance the adhesion of the leukaemic cells. Moreover, G-CSF and IFNγ joint effect led to the reduction in the adhesion capacity of the effector PMNs. It appears, that therapeutic effect of anti-CD19/anti-CD64 BsAb on enhancing attachment of leukaemic cells to PMNs in CLL patients is limited and its application should be based on the assessment of individual capacity of the patients' phagocytic cells.
慢性淋巴细胞白血病（CLL）是美国和欧洲（包括格鲁吉亚）最常见的成人白血病。CLL 表现为外周淋巴器官和组织以及骨髓中克隆性扩张和积累 CD5+CD19+CD23+细胞。尽管目前有新的分子和免疫疗法，但该疾病仍然无法治愈，这些方法与化疗一起导致了“精准治疗”方法。大多数免疫疗法都是基于治疗性抗体调动免疫反应抗肿瘤潜能的能力。双特异性抗体（BsAb）也被认为可用于治疗 CLL，其中吞噬细胞在破坏靶 CLL 细胞方面发挥关键效应作用。抗 CD19/抗 CD64 BsAb 结合 CLL 细胞上的 CD19 受体和单核细胞和活化的多形核中性粒细胞（PMN）上的 CD64 受体（FcγRI），从而诱导白血病细胞的吞噬作用。本研究旨在评估抗 CD19/CD64 BsAb 通过 PMN 增强 CLL 细胞黏附的能力，PMN 是完整的或用 G-CSF 和 IFNγ 细胞因子激活的。用 Red Fluoresent Linker 染色分离的 16 名患者的 CLL 细胞的细胞膜，并将 CLL 细胞与分离的自体 PMN 共孵育 4 小时或 24 小时，这些 PMN 是完整的或用 G-CSF 和/或 IFNγ 预先刺激的。用 FACScan 流式细胞仪通过门控 PMN 上黏附的 RFL 染色的 CLL 细胞分析 PMN/CLL 细胞黏附。结果是异质的。我们的数据表明，抗 CD19/抗 CD64 BsAb 增强自体 PMN 对白血病细胞附着的能力有限。这部分可以通过 PMN 自发附着于自体 CLL 细胞的显著强度来解释。单独或联合用 G-CSF 和 INFγ 预处理 CLL 患者的 PMN 并没有增强白血病细胞的黏附。此外，G-CSF 和 IFNγ 的联合作用导致效应 PMN 的黏附能力降低。似乎，抗 CD19/抗 CD64 BsAb 增强 CLL 患者白血病细胞与 PMN 附着的治疗效果有限，其应用应基于评估患者吞噬细胞的个体能力。
