Tang, H., **ong, Y., Gan, S., Fei, L., Guo, L., Zhang, K., Li, H., Fu, T., Wu, Q. and Tan, W., 2025. CD4 aptamer-engineered cell platforms enhance anti-tumor immunity in triple-negative breast cancer. Cell Biomaterials.

CD4 aptamer-engineered cell platforms enhance anti-tumor immunity in triple-negative breast cancer

The bigger picture
Current immunotherapies’ overreliance on CD8+ T cells fail patients with major histocompatibility complex class I (MHC I)-deficient cancers. Recently, CD4+ T cells offer a transformative solution: they help CD8+ T cells to kill MHC I+ tumors, directly kill MHC II+ tumors, and mobilize antigen-presenting cells/natural killer (NK) cells against MHC-deficient tumors. The therapeutic potential of CD4+ T cells has been confirmed in various types of cancer, including MHC-deficient melanomas, glioblastoma, and breast cancers. However, optimizing CD4+ T cell infiltration and activation within the tumor microenvironment remains a critical challenge to fully realizing their therapeutic potential. To overcome this, we developed a CD4 aptamer-engineered liquid nitrogen-treated cancer cell system (AptCD4-LNTs) to selectively activate and recruit CD4+ T cells for improved anti-tumor immunity in triple-negative breast cancer (TNBC). We revealed that CD4+ T cells reshape the tumor microenvironment and enhance MHC II anti-tumor immune response to inhibiting TNBC tumors. This strategy unlocks the full anti-tumor potential of CD4+ T cells, offering new avenues for TNBC immunotherapy and CD4+ T cell therapy.

研究全景
当前免疫疗法对 CD8⁺T 细胞的过度依赖，使其在治疗主要组织相容性复合体 I 类（MHC I 类）缺陷型癌症患者时效果不佳。近年来，CD4⁺T 细胞为这一问题提供了突破性解决方案：它们既能辅助 CD8⁺T 细胞杀伤 MHC I 类阳性肿瘤，又能直接杀伤 MHC II 类阳性肿瘤，还可动员抗原呈递细胞 / 自然杀伤（NK）细胞对抗 MHC 缺陷型肿瘤。CD4⁺T 细胞的治疗潜力已在多种癌症中得到证实，包括 MHC 缺陷型黑色素瘤、胶质母细胞瘤和乳腺癌。
然而，要充分发挥 CD4⁺T 细胞的治疗潜力，如何在肿瘤微环境中优化其浸润与活化水平仍是关键挑战。为攻克这一难题，我们开发了一种经 CD4 适配体工程化改造的液氮处理癌细胞系统（AptCD4-LNTs），该系统可选择性活化并募集 CD4⁺T 细胞，从而增强三阴性乳腺癌（TNBC）的抗肿瘤免疫效应。研究发现，CD4⁺T 细胞能够重塑肿瘤微环境，并通过增强 MHC II 类抗肿瘤免疫应答来抑制 TNBC 肿瘤生长。这一策略充分释放了 CD4⁺T 细胞的抗肿瘤潜力，为 TNBC 免疫治疗及 CD4⁺T 细胞疗法开辟了新途径。

Highlights
• CD4 aptamer captures and activates CD4+ T cells
• AptCD4-LNT drives in vivo infiltration and activation specific to CD4+ T cells
• Activated CD4+ T cells potently inhibits TNBC tumor growth by MHC II response
• CD4+ T cells remodel TNBC immunity by recruiting B, DC, and NK cells
研究亮点
CD4 适配体可捕获并活化 CD4⁺T 细胞
AptCD4-LNTs 系统可在体内驱动 CD4⁺T 细胞的特异性浸润与活化
活化的 CD4⁺T 细胞可通过 MHC II 类免疫应答强效抑制 TNBC 肿瘤生长
CD4⁺T 细胞可通过募集 B 细胞、树突状细胞（DC）和 NK 细胞，重塑 TNBC 的免疫微环境

Summary
While CD8+ T cells are primary anti-tumor effectors, CD4+ T cells play critical helper and direct killer roles, yet their clinical use is hindered by poor tumor infiltration and the immunosuppressive tumor microenvironment (TME). To overcome this, we developed cluster of differentiation 4 (CD4) aptamer-engineered liquid nitrogen-treated cancer cells (AptCD4-LNTs) designed to selectively activate and recruit CD4+ T cells for improved anti-tumor immunity in triple-negative breast cancer (TNBC). This system leverages the CD4 aptamer’s specificity for CD4+ T cells and the homing capacity of LNTs to drive targeted infiltration and activation of CD4+ T cells within the TNBC TME. Activated CD4+ T cells, in turn, enhance the infiltration and activity of natural killer (NK) cells, B cells, and dendritic cells, reshaping the immune landscape and potentiating anti-tumor responses. Our findings highlight the pivotal role of CD4+ T cells in TNBC immunotherapy and present a promising strategy for advancing CD4-targeted treatments.
研究摘要

尽管 CD8⁺T 细胞是主要的抗肿瘤效应细胞，但 CD4⁺T 细胞在免疫反应中同时扮演着关键的辅助角色与直接杀伤角色。然而，由于肿瘤浸润能力不足以及肿瘤微环境（TME）的免疫抑制特性，CD4⁺T 细胞的临床应用受到阻碍。
为解决这一问题，我们开发了一种经分化簇 4（CD4）适配体工程化改造的液氮处理癌细胞（AptCD4-LNTs）。该系统旨在选择性活化并募集 CD4⁺T 细胞，以增强三阴性乳腺癌（TNBC）的抗肿瘤免疫功能。其核心机制在于：利用 CD4 适配体对 CD4⁺T 细胞的特异性结合能力，以及液氮处理癌细胞（LNTs）的归巢能力，驱动 CD4⁺T 细胞在 TNBC 肿瘤微环境中实现靶向浸润与活化。
随后，活化的 CD4⁺T 细胞可进一步增强自然杀伤（NK）细胞、B 细胞和树突状细胞的浸润与活性，从而重塑肿瘤免疫格局，强化抗肿瘤免疫应答。本研究结果凸显了 CD4⁺T 细胞在 TNBC 免疫治疗中的核心作用，并为推进以 CD4 为靶点的治疗方案提供了一种具有潜力的策略。

实验方法部分：

CD4 protein binding assay
0.005 μmol DBCO-modified aptamers were incubated with 0.5 mg azide-functionalized magnetic beads (PuriMag Biotech) at 25°C overnight. After magnetic separation and washing, aptamer-conjugated beads were annealed at 95°C for 10 min. Subsequently, beads were co-incubated with 20 μg/mL fluorescein isothiocyanate (FITC)-labeled CD4 protein (ACROBiosystems) in binding buffer for 90 min. After magnetic separation and washing, CD4 protein binding was quantified via flow cytometry.

客户使用我司叠氮磁珠  叠氮磁珠|Azide 磁珠|炔烃标记蛋白点击偶联|PuriMag G-Azide Beads|Azide magnetic bead-生物磁珠专家 - Purimag Bead 官网 | 高品质生物磁珠解决方案