Neuro-PASC is characterized by enhanced CD4+ and diminished CD8+ T cell responses to SARS-CoV-2 Nucleocapsid protein

Many people experiencing long COVID symptoms, or post-acute sequelae of SARS-CoV-2 infection (PASC), suffer from debilitating neurologic symptoms (Neuro-PASC). Although symptoms of Neuro-PASC are widely documented, it is still unclear whether virus-specific adaptive immunity is affected in these individuals. We report that Neuro-PASC patients exhibit distinct immunological signatures composed of elevated CD4+ T cell responses toward the C-terminal region of SARS-CoV-2 Nucleocapsid protein when examined both functionally and using TCR sequencing. In contrast, Neuro-PASC patients also have diminished activation of CD8+ memory T cells and increased IL-6 production to Nucleocapsid. Elevated plasma immunoregulatory and reduced pro-inflammatory and antiviral response signatures were evident in Neuro-PASC patients compared with COVID convalescent controls without lasting symptoms, correlating with worse neurocognitive dysfunction. These data provide new insight into the impact of virus-specific cellular immunity on the pathogenesis of long COVID and pave the way for the rational design of predictive biomarkers and therapeutic interventions. Genomic DNA samples from Neuro-PASC (NP; experimental) and COVID convalescent controls (CC; control) underwent TCR-sequencing through the Adaptive Biotechnologies ImmunoSEQ platform. ***Adaptive Biotechnologies does not release raw data.***