✍🏼 Kerui Wu, Feng Lyu, Shih-Ying Wu, Sambad Sharma, Ravindra Pramod Deshpande, Abhishek Tyagi, Dan Zhao, Fei Xing, Ravi Singh, Kounosuke Watabe

🏠 Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC

📑 Science Advances (2023)

Abstract
Breast cancer has been shown to be resistant to immunotherapies. To overcome this challenge, we developed an active immunotherapy for personalized treatment based on a smart nanovesicle. This is achieved by anchoring membrane-bound bioactive interleukin 2 (IL2) and enriching T cell–promoting costimulatory factors on the surface of the dendritic cell–derived small extracellular vesicles. This nanovesicle also displays major histocompatibility complex–bound antigens inherited from tumor lysate–pulsed dendritic cell. When administrated, the surface-bound IL2 is able to guide the nanovesicle to lymphoid organs and activate the IL2 receptor on lymphocytes. Furthermore, it is able to perform antigen presentation in the replacement of professional antigen-presenting cells. This nanovesicle, named IL2-ep13nsEV, induced a strong immune reaction to rescue 50% of the mice in our humanized patient-derived xenografts, sensitized cancer cells to immune checkpoint inhibitor treatment, and prevented the recurrence of resected tumors. This paradigm presents a feasible strategy for the treatment and prevention of metastatic breast cancer.

How the WOLF was used in this study
The researchers used a WOLF Cell Sorter to enrich specific immune or engineered cell populations based on intense fluorescence prior to downstream functional and molecular analyses. By sorting cells with high fluorescent signal, the WOLF platform enabled the team to isolate the most relevant cell subsets—expressing engineered receptors or markers critical for their personalized immunotherapy strategy—while preserving cell viability and functional integrity for subsequent assays. This sorting step was crucial for ensuring that the immunotherapy constructs and immune cells being studied were present in pure, well‑defined populations, thereby improving the reliability and interpretability of their in vitro and in vivo experimentation on cancer immunotherapy efficacy.