Co-delivering macrophage engager mRNA and PD-L1 antibody via tumor-responsive nanoparticles for glioblastoma immunotherapy

1.논문 제목: Co-delivering macrophage engager mRNA and PD-L1 antibody via tumor-responsive nanoparticles for glioblastoma immunotherapy

2.저자명: Haoge Zhang, JiaMiao, LinGao, Xuhong Yang, Zhengcheng Yun, LeiDong, Wanqing Cheng, Yuqi Wang, Hui Yang, Ying Zhou, Yini Zhu & Jinbing Xie

3.출처 및 게제일: Nature communications, 11 April 2026

4.DOI: https://doi.org/10.1038/s41467-026-71646-y

5.Abstract: Bispecific immune cell engagers, particularly bispecific T-cell engagers, show limited efficacy in solid tumors such as glioblastoma (GBM) due to systemic toxicities, poor T cell infiltration, and restricted drug penetration. We develop PL@mBiME, a multifunctional lipid nanoparticle (LNP) platform that enables brain tumor–targeted delivery and sustained in vivo expression of mRNA encoding a bispecific macrophage engager (BiME). The BiME simultaneously targets ErbB2 on glioma cells and CD206 onM2macrophages, reprogramming macrophages toward pro-inflammatory M1 phenotype while promoting macrophage–tumor cell bridging, enhancing tumor cell phagocytosis and antigen presentation. PL@mBiME incorporates pH-responsive charge reversal to improve tumor accumulation and lysosomal escape as well as glutathione-triggered release of surface-conjugated PD-L1 antibody to amplify anti-tumor immunity. Across multiple GBM models, this coordinated activation of innate and adaptive immunity induces tumor regression, prolongs survival, and generates durable immune memory without significant toxicity.

6.한글 초록 요약본: 교모세포종은 혈액-뇌 장벽 (BBB)과 면역억제성 종양미세환경 (TME)으로 인해 기존 면역치료의 효과가 제한적임. 본 연구에서는 Bispecific macrophage engager (BiME) mRNA와 PD-L1 항체를 동시에 전달하는 종양 반응성 지질나노입자 PL@mBiME를 개발함. PL@mBiME는 BBB를 통과한 후 종양의 산성 환경에서 세포 흡수를 증가시키고 높은 glutathione (GSH) 농도에서 PD-L1 항체를 선택적으로 방출하도록 설계됨. 발현된 BiME는 ErbB2를 발현하는 종양세포와 CD206 양성 M2 macrophage를 연결하여 M1 macrophage로 재분극시키고 식세포작용 및 항원 제시를 촉진함. Orthotopic GBM 모델에서 우수한 BBB 투과와 종양 선택적 전달을 확인하였으며 종양 성장 억제, 생존기간 연장, CD8+ T 세포 활성화 및 장기면역기억을 유도함. 또한 유의한 전신 독성 없이 선천면역과 적응면역을 동시에 활성화하는 새로운 mRNA 기반 면역치료 전략의 가능성을 제시함.

7.한글 논문 요약본

7-1: Introdiction: 교모세포종(GBM)은 예후가 매우 불량한 뇌종양으로 BBB와 면역억제성 종양미세환경 때문에 기존 면역치료의 효과가 제한적임. 특히 종양 내 대부분의 macrophage는 M2 phenotype (CD206+)으로 존재하여 종양 성장을 촉진함. 또한 ErbB2는 GBM에서 과발현되는 치료 표적임. 기존 bispecific engager는 반감기가 짧고 BBB 통과가 어려운 한계가 있음. 이를 극복하기 위해 본 연구에서는 BiME mRNA를 체내에서 발현시키고 BBB 투과 (A2 peptide), pH 반응성 (DCPA), GSH 반응성 PD-L1 방출 기능을 갖는 PL@mBiME를 개발하여 macrophage 재분극과 PD-L1 차단을 동시에 유도하고자 함.

7-2: Methods

• ErbB2-targeting scFv와 RP-182 (CD206 targeting peptide)를 포함한 BiME mRNA를 제작하고 PD-L1 항체를 결합한 PL@mBiME를 제조함.

• Nanoparticle의 크기, zeta potential, encapsulation efficiency, pH 및 GSH 반응성을 평가함.

• RAW264.7, BMDM, GL261 세포에서 세포 흡수, lysosomal escape, mRNA 발현 및 macrophage 재분극을 분석함.

• In vitro BBB model과 orthotoptic GL261 mouse model에서 BBB 투과 및 종양 축적을 확인함.

• MRI, IVIS imaging, 조직염색 (H&E, Ki67, TUNEL), Flow cytometry를 이용하여 항종양 효과와 면역반응을 분석함.

• CD8 T cell depletion 및 macrophage depletion을 통해 치료 효과에 기여하는 면역세포를 확인함.

  
  

7-3: Results

7-3-1) PL@mBiME 제작 및 특성 분석: 약 80nm 크기의 안정적인 lipid nanoparticle을 제작하였으며 높은mRNA encapsulation efficiency를 확인함. 산성 환경에서는 표면 전하가 음전하에서 양전하로 전환되었고 높은 GSH 환경에서는 PD-L1 항체가 선택적으로 방출되어 종양 특이적 전달이 가능함

을 확인함.

7-3-2) 세포 전달 효율 및 mRNA 발현 향상: 산성 환경에서는 nanoparticle의 세포 흡수와 lysosomal escape가 증가함. RAW264.7과 GL261 세포 모두에서 높은 mRNA 발현을 보였으며 세포 독성은 거의 나타나지 않아 우수한 전달 효율과 생체적합성을 확인함.

7-3-3) Macrophage 활성화 및 식세포작용 증가: PL@mBiME는 M2 macropahge를 M1 phenotype으로 효과적으로 재분극시킴. Macrophage의 종양세포 phargocytosis가 크게 증가하였으며 IL-1ß와 TNF-α 는 증가하고 IL-10은 감소하여 항종양 면역반응이 활성화됨. ErbB2 발현이 높은 종양세포에서 macrophage와 종양세포의 결합 및 식세포작용이 더욱 증가함.

7-3-4) BBB 투과 및 종양 선택적 전달: A2 peptide를 통해 BBB를 효과적으로 통과하였으며 종양 부위에 선택적으로 축적됨. 종양 조직에서 높은 BiME 발현이 확인되었으며 DCPA는 산성 종양환경에서 전달 효율과 발현을 더욱 향상시킴.

7-3-5) Orthotopic GBM에서 우수한 항종양 효과: PL@mBiME는 모든 군에서 가장 강력한 종양 성장 억제 효과와 생존기간 연장을 나타냄. GL261 모델에서는 약 80%의 마우스에서 complete tumor regression이 관찰되었으며 Ki67 감소와 TUNEL 증가를 통해 종양세포 증식 억제와 apoptosis 증가를 확인함. 체중 변화와 주요 장기 조직 및 혈액검사에서 유의한 독성은 관찰되지 않음.

7-3-6) 종양미세환경 재구성: 종양 내 M1 macrophage와 MHCⅡ 발현이 증가하고 M2 macrophage와 SIRPα는 감소하여 macrophage의 항원 제시 및 식세포 기능이 향상됨. TNF-α, IL-1ß, IFN-γ는 증가하고 IL-10은 감소하여 종양 미세환경이 항종양성으로 변화함.

7-3-7) 적응면역 활성화 및 면역기억 형성: CD 8+ T cell, NK cell 및 dendritic cell의 침윤이 증가하고 Treg와 MDSC는 감소함. Macrophage depletion시 치료 효과가 가장 크게 감소하여 macrophage가 핵심적인 항종양 효과를 매개함을 확인함. 완전 관해된 마우스에서는 종양 재도전 후에도 종양 성장이 억제되어 장기 면역기억이 형성됨을 확인함.

8.대표 Figure