Professor Yongtaek Lim's research team at the Sungkyun Advanced Institute of Nano-Technology (SAINT), including co-first authors Yeon Jeong Yoo (Ph.D. candidate) and Soohyun Kim (M.S. student), has developed a multiscale dynamic immunomodulation vaccine adjuvant platform, SE (Trojan-TLR7/8a), that induces broad and durable immune responses against infectious diseases.

Professor Lim's team previously developed Trojan-TLR7/8a—the world’s first engineered immunomodulator capable of dynamically controlling immune activation kinetics—published in Nature Nanotechnology (2023). They subsequently demonstrated its efficacy as a novel immunotherapy in various tumor models (Advanced Materials, 2023, 2024) and successfully transferred the core technology to a domestic biotech startup.

In this study, the team introduced an innovative approach that precisely regulates both the delivery speed and location of vaccines at macroscopic and microscopic levels—so-called multiscale immunomodulation. This strategy enhances both the quality and persistence of immune responses by promoting the migration of non-exhausted antigen-presenting cells (APCs) to lymph nodes, ensuring efficient co-delivery of antigen and adjuvant, and enabling sustained immune activation within the lymph nodes, ultimately leading to robust T cell responses.

Conventional vaccines have primarily relied on antibody-mediated immunity, with limitations in inducing long-term immune memory and responding to viral variants. Notably, they fail to effectively elicit CD8⁺ T cell responses, which are essential for the elimination of infected cells and maintenance of memory immunity. Although mRNA vaccines marked a major advancement, they still face challenges related to variant coverage, immune durability, and stringent storage conditions, highlighting the need for a new vaccine design strategy capable of effectively inducing T cell-based immunity.

To address these limitations, the research team developed the SE(Trojan-TLR7/8a) platform by incorporating Trojan-TLR7/8a, a spatiotemporally controllable TLR7/8 agonist, into a clinically approved squalene-based nanoemulsion (SE). This formulation ensures stable loading and enables lyophilization, making it highly applicable for real-world vaccine storage and distribution.

Furthermore, through collaborative research with the Institute for Basic Science (IBS) Korea Virus Research Institute (Director Young Ki Choi) and the College of Veterinary Medicine at Chungnam National University (Professor Jong-Soo Lee), this study demonstrated broad and long-term protective efficacy against various pathogenic models, including SARS-CoV-2 variants, influenza virus subtypes, and severe fever with thrombocytopenia syndrome virus (SFTSV).

The SE (Trojan-TLR7/8a)-vaccinated group exhibited a 100% survival rate. The platform effectively induced neutralizing antibody production by enhancing follicular helper T cell and germinal center B cell response, and also promoted antigen-specific polyfunctional CD8⁺ T cell generation. Recently, the team also validated the efficacy and mechanism of action (MOA) of Alum + Liposome(Trojan-TLR7/8a)-based adjuvant platforms, which was published in Nature Communications (2025).

The study has been published in Cellular and Molecular Immunology (IF: 21.8), a globally recognized journal in the fields of immunology and biomedical science (Online publication in June 25^th ,2025).

Authors: Yeon-Jeong Yoo (First Author, Ph.D. Candidate), Suhyun Kim (Co-First Author, Master’s Student), Jooa Song (Co-Author, Integrated Master’s-Ph.D. Program), Yongtaek Lim (Corresponding Author, Professor at Sungkyunkwan University)
Title: Multiscale dynamic immunomodulation by a nanoemulsified Trjoan-TLR7/8a adjuvant for robust protection against heterologous pandemic and endemic viruses (Cellular and Molecular Immunology; IF=21.8, 2025)
D.O.I.: https://www.nature.com/articles/s41423-025-01306-6

[Figure 1] Development process and mechanism of action of SE (Trojan-TLR7/8a)

[Figure 2] Induction of antigen-specific multifunctional CD8+ T cells and neutralizing antibodies by SE (Trojan-TLR7/8a) in a SARS-CoV-2 model