PO.IM01.05 · 免疫学
ST6GAL1增强的CAR-T细胞改善在DLBCL中的持久性和抗肿瘤疗效
ST6GAL1 enhanced CAR-T cells improve persistence and antitumor efficacy in DLBCL
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
弥漫性大B细胞淋巴瘤（DLBCL）是最常见且最具侵袭性的B细胞淋巴瘤，对于复发或难治性患者预后不佳。嵌合抗原受体（CAR）-T细胞疗法提供了一种有前景的治疗选择，然而有限的持久性和功能损伤仍是实现持久应答的主要障碍。Galectin（Gal）-3是一种在DLBCL微环境中高表达的碳水化合物结合蛋白，已被认为与T细胞功能障碍有关，但其在CAR-T细胞损伤中的作用尚未完全明确。我们假设Gal-3与CAR-T细胞表面糖类结合，从而促进凋亡和效应功能丧失。ELISA显示，与健康对照相比，DLBCL患者血清中Gal-3水平显著升高（p<0.001）。流式细胞术证实Gal-3与CAR-T细胞强结合，且这与凋亡增加相关（p<0.01）。为克服这一问题，我们改造CAR-T细胞使其过表达alpha2,6唾液酸转移酶ST6GAL1（ST6 OE CAR-T细胞），该酶添加已知可掩盖Gal-3结合糖类的alpha2,6-唾液酸。ST6 OE CAR-T细胞显示出明显减少的Gal-3结合、更低的凋亡（p<0.001），以及在Gal-3高表达的DLBCL共培养中改善的活力和细胞毒性。细胞因子分析进一步显示，对照CAR-T细胞分泌升高水平的白细胞介素-5（IL-5），一种与抗肿瘤活性降低相关的Th2相关细胞因子。相比之下，ST6 OE CAR-T细胞表现出显著更低的IL-5产生（p<0.01），表明其向更具细胞毒性的Th1样功能表型转变。在DLBCL异种移植模型中，与对照CAR-T细胞相比，ST6 OE CAR-T治疗显著减少了肿瘤负荷并改善了生存期（p<0.001）。这些发现证明，ST6GAL1过表达可减轻凋亡和IL-5相关的功能障碍，增强CAR-T细胞的持久性和抗肿瘤疗效。通过ST6GAL1对CAR-T细胞进行糖工程改造，为改善DLBCL患者的治疗结局提供了一种新颖的策略。
查看英文原文 English abstract
Diffuse large B cell lymphoma (DLBCL) is the most common and aggressive B cell lymphoma, with poor outcomes for patients who relapse or are refractory to treatment. Chimeric antigen receptor (CAR)-T cell therapy offers a promising therapeutic option, yet limited persistence and functional impairment remain major barriers to durable responses. Galectin (Gal)-3, a carbohydrate-binding protein highly expressed in the DLBCL microenvironment, has been implicated in T cell dysfunction, but its role in CAR-T cell impairment has not been fully defined. We hypothesized that Gal-3 binds to CAR-T cell surface glycans, promoting apoptosis and loss of effector function. ELISA revealed significantly elevated Gal-3 levels in serum from DLBCL patients versus healthy controls ( p <0.001). Flow cytometry confirmed strong Gal-3 binding to CAR-T cells, which correlated with increased apoptosis ( p <0.01). To overcome this, we engineered CAR-T cells to overexpress the alpha2,6 sialyltransferase ST6GAL1 (ST6 OE )CAR-T cells, which adds alpha2,6-sialic acids known to mask Gal-3-binding glycans. ST6 OE CAR T cells displayed markedly reduced Gal-3 binding, lower apoptosis ( p <0.001), and improved viability and cytotoxicity in Gal-3 high DLBCL co-cultures. Cytokine profiling further revealed that control CAR-T cells secreted elevated levels of interleukin-5 (IL-5),a Th2-associated cytokine linked to reduced antitumor activity. In contrast, ST6 OE CAR-T cells exhibited significantly lower IL-5 production ( p <0.01), indicating a shift toward amore cytotoxic, Th1-like functional profile. In a DLBCL xenograft model, ST6 OE CAR-T treatment significantly reduced tumor burden and improved survival compared to control CAR-T cells ( p <0.001). These findings demonstrate that ST6GAL1 overexpression mitigates apoptosis and IL-5-associated dysfunction, enhancing CAR-T cell persistence and antitumor efficacy. Glycoengineering CAR-T cells via ST6GAL1 provides a novel strategy to improve therapeutic outcomes for patients with DLBCL.
利益披露 Disclosure
L. M. Lau, None..
M. Suarez, None..
B. Fernandez, None..
A. Berdalinova, None..
J. Souchack, None..
A. Antonopoulos, None..
A. Dell, None..
S. Haslam, None..
C. J. Dimitroff, None.