Meng, D.; Li, X.; Rao, X.; Huang, X.; Ding, H.; Deng, Q.; Li, L.; Ma, W.; Tao, Y.; Feng, X.; Liu, X.

Effective vaccine adjuvants are crucial for eliciting strong, specific, and long-lasting adaptive immune responses. However, traditional vaccine and adjuvant development is often hindered by prolonged animal testing, reliance on singular evaluation metrics, and batch variability, limiting the comparative analysis of immune responses induced by different adjuvants. To our knowledge, systematic adjuvant-focused analysis in human immune organoids remains limited, particularly across distinct antigen-conditioned immune baselines. Here, we established a matrix supported human tonsil immune organoid (M-hTIO) platform, derived from tonsil tissue for systemic adjuvant evaluation. Within 2 days, the platform replicated key germinal center (GC) features, with the potential for antigen-specific antibody production and plasmablast differentiation. Dynamic GC formation and T-B cell interactions were tracked using light-field imaging. Notably, IL-21 significantly accelerates GC-like remodeling and enhanced immune responses. Employing bulk cell transcriptomics we systematically analyzed early immune signatures and prolonged adaptive responses induced by five clinical-grade adjuvants (Alum, MnJ{beta}, AddaSO3, R848, ODN 1018) paired with influenza HA and SARS-CoV-2 RBD antigens across only adjuvant, weak and strong memory backgrounds. By integrating early and prolonged response phases, M-hTIO captured complementary dimensions of adjuvant activity, distinguishing rapid immune activation from sustained adaptive remodeling. Importantly, early activation signatures and prolonged adaptive remodeling provided complementary information, highlighting the value of temporally resolved adjuvant evaluation. AddaSO3 showed a consistent activity pattern across early and prolonged response phases, supporting both rapid immune activation and sustained adaptive remodeling. Moreover, our findings reveal shared/exclusive signaling pathways and gene networks. These results represent systematic and comparative analysis of clinically tested vaccine adjuvants in a human model, paving the way for high-throughput systems vaccinology research.