Dendritic Cells: An Exhausted Checkpoint in Chronic Viral Syndromes, Long Covid and Beyond

Dendritic cells (DCs) are pivotal in bridging innate and adaptive immunity through antigen presentation and cytokine signaling. While T cell exhaustion has become a central paradigm in chronic infections and cancer, dendritic cell exhaustion remains under-recognized. In this article, I propose that DC exhaustion is a key perpetuating mechanism in chronic viral syndromes, including Long Covid. Drawing on classical immunology, recent findings in post-viral syndromes, and my own empirical research rooted in Traditional Chinese Medicine (TCM), I propose a testable model: that Lingering Pathogenic Illnesses, as described in TCM, such as post-viral syndromes correlate mechanistically with exhausted antigen-presenting cell states. Through integration of immunological mechanisms and TCM clinical patterns, I argue that immune dysfunction in diseases like Long Covid must be addressed with DC restoration. This hypothesis has far-reaching implications for treatment, vaccine response, and immune resilience in the face of persistent viral threats and complex diseases.