CAR-T Therapy as a System Transition: A Dynamical Interpretation of Immune Reprogramming Conceptual Note — URM Series

CAR-T therapy is not only a targeted intervention — it is an induced system transition with state-dependent outcomes. This conceptual note introduces a systems-dynamic interpretation of chimeric antigen receptor T-cell (CAR-T) therapy within the framework of the Universal Resonance Model (URM). CAR-T therapy is typically described in terms of molecular targeting and cellular engineering. However, this perspective does not fully account for the observed variability in clinical outcomes, including durable remission, relapse, cytokine release syndrome, and immune-mediated toxicity. In this work, CAR-T therapy is reframed as a system-level perturbation acting on a dynamic immune network. Rather than functioning solely as a targeted cytotoxic intervention, CAR-T is conceptualized as an induced state transition, with outcomes determined by the system’s pre-existing stability, coupling structure, and temporal phase. This interpretation provides a coherent explanation for variability in clinical responses and highlights the importance of state-dependent effects, system stability, and timing in the evaluation and development of cell-based therapies. The note extends prior URM work on instability dynamics, early-warning signals (σ², ρ(τ), λ₁), and phase-dependent intervention, representing a first explicit application of the model to engineered cell therapies.