Harnessing CAR-NK Cell Therapy for Targeted Glioblastoma Treatment   — ASN Events
  1. Schedule
  2. Poster Session Two
  3. Harnessing CAR-NK Cell Therapy for Targeted Glioblastoma Treatment  

Harnessing CAR-NK Cell Therapy for Targeted Glioblastoma Treatment   (#221)

Jérémy Robert 1 2 , Alice Mac Donald 1 2 , Hugo Roméro 1 , David Suissa 1 2 3 , Clara Soulard 1 2 , Soraya Benhaddou 1 , Isabelle Cousineau 1 , Aissa Benyoucef 1 , Khampoun Sayasith 1 , Kathie Béland 1 , Scott McComb 4 , Elie Haddad 1 2 5
  1. CHU Sainte-Justine, Montréal, Québec, Canada
  2. Immunology, Université de Montréal, Montréal, Québec, Canada
  3. Cancer Biology, University of Miami Miller School of Medicine, Miami, Florida, United States
  4. Human Health Therapeutics Research Center, National Research Council Canada, Ottawa, Ontario, Canada
  5. Pediatrics, Université de Montréal, Montréal, Québec, Canada

Introduction

Glioblastoma is an aggressive brain tumor with a poor prognosis. Chimeric Antigen Receptor T (CAR-T) cell therapy has shown success in hematologic cancers but faces limitations in treating solid tumors like glioblastoma. These limitations include T cell exhaustion, severe side effects, and challenges in targeting tumor heterogeneity. To overcome these obstacles, we propose to develop a CAR-NK therapy targeting HER2, a tumor-associated antigen overexpressed in approximately 80% of GBM cases, and incorporating an IL-15 superagonist to enhance NK cell function.

Method

Primary NK cells were isolated from healthy donor PBMCs and expanded with feeder cells (NKAES). NK cells were genetically modified using lentiviral vectors expressing a baboon envelope pseudotype for improved transduction (BaEV). NK cells were transduced with lentiviruses coding for a nanobody-based CAR targeting HER2 containing 4-1BB and CD3z domains, combined with a receptor-linker-IL-15 (RLI), a fusion molecule of human IL-15 covalently linked to IL-15Ra sushi domain to enhance NK cell persistence and survival.

Results

Transduced NKAES cells exhibited stable CAR expression over time. Co-expression of IL-15 RLI, quantified by ELISA, enhanced the proliferation of NK cells. CAR specificity was confirmed through cytotoxicity assays using CAR-NK cells against both HER2neg- and HER2high-U87-MG cells. A significantly increased cytotoxicity HER2 high U87-MG cell was observed, demonstrating the specificity of the CAR-NKs. In a serial killer assay, NK cells co-expressing the HER2-targeted CAR and IL-15s showed robust and sustained cytotoxicity against HER2 high U87-MG cells for over 12 days.

Conclusion

Anti-HER2 CAR-NK targeting specific antigens have shown effective, antigen-specific tumor cell killing and capacity for serial killing. The co-expression of an IL-15 superagonist synergistically enhanced NK cell proliferation and cytotoxicity. This efficacy will be validated in an in vivo NSG mouse model. This approach could offer a potent and less toxic alternative to traditional CAR-T therapies for solid tumors.