Wang Lan, Suryawanshi Gajendra W, Kim Shihyoung, Guan Xin, Bonifacino Aylin C, Metzger Mark E, Donahue Robert E, Kim Sanggu, Chen Irvin S Y
Department of Microbiology, Immunology and Molecular Genetics, UCLA, Los Angeles, CA, 90095, USA.
Division of Hematology-Oncology, Dept of Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA.
Heliyon. 2023 Aug 28;9(9):e19435. doi: 10.1016/j.heliyon.2023.e19435. eCollection 2023 Sep.
Selective T-cell depletion prior to cell or organ transplantation is considered a preconditioning regimen to induce tolerance and immunosuppression. An immunotoxin consisting of a recombinant anti-CD3 antibody conjugated with diphtheria toxin was used to eliminate T-cells. It showed significant T-cell depletion activity in the peripheral blood and lymph nodes in animal models used in previous studies. To date, a comprehensive evaluation of T-cell depletion and CD3 proliferation for all lymphoid tissues has not been conducted. Here, two rhesus macaques were administered A-dmDT390-SCFBdb (CD3-IT) intravenously at 25 μg/kg twice daily for four days. Samples were collected one day prior to and four days post administration. Flow cytometry and immunofluorescence staining were used to evaluate treatment efficiency accurately. Our preliminary results suggest that CD3-IT treatment may induce higher depletion of CD3 and CD4 T-cells in the lymph nodes and spleen, but is ineffective in the colon and thymus. The data showed a better elimination tendency of CD4 T-cells in the B-cell zone relative to the germinal center in the lymph nodes. Further, CD3-IT treatment may lead to a reduction in germinal center T follicular helper CD4 cells in the lymph nodes compared to healthy controls. The number of proliferating CD3 T-cell indicated that repopulation in different lymphoid tissues may occur four days post treatment. Our results provide insights into the differential efficacy of CD3-IT treatment and T-cell proliferation post treatment in different lymphoid tissues. Overall, CD3-IT treatment shows potential efficacy in depleting T-cells in the periphery, lymph nodes, and spleen, making it a viable preconditioning regimen for cell or organ transplantation. Our pilot study provides critical descriptive statistics and can contribute to the design of larger future studies.
在细胞或器官移植前进行选择性T细胞清除被认为是诱导耐受和免疫抑制的预处理方案。一种由重组抗CD3抗体与白喉毒素偶联而成的免疫毒素被用于清除T细胞。在先前研究中使用的动物模型中，它在外周血和淋巴结中显示出显著的T细胞清除活性。迄今为止，尚未对所有淋巴组织的T细胞清除和CD3增殖进行全面评估。在此，对两只恒河猴静脉注射A-dmDT390-SCFBdb（CD3免疫毒素），剂量为25μg/kg，每日两次，共四天。在给药前一天和给药后四天采集样本。使用流式细胞术和免疫荧光染色准确评估治疗效果。我们的初步结果表明，CD3免疫毒素治疗可能会在淋巴结和脾脏中诱导更高程度的CD3和CD4 T细胞清除，但在结肠和胸腺中无效。数据显示，相对于淋巴结生发中心，B细胞区的CD4 T细胞清除趋势更好。此外，与健康对照相比，CD3免疫毒素治疗可能会导致淋巴结中生发中心T滤泡辅助性CD4细胞减少。增殖性CD3 T细胞的数量表明，治疗后四天不同淋巴组织中可能会发生细胞再填充。我们的结果为CD3免疫毒素治疗在不同淋巴组织中的差异疗效以及治疗后T细胞增殖提供了见解。总体而言，CD3免疫毒素治疗在清除外周、淋巴结和脾脏中的T细胞方面显示出潜在疗效，使其成为细胞或器官移植可行的预处理方案。我们的初步研究提供了关键的描述性统计数据，并可为未来更大规模研究的设计做出贡献。
