A recent study published by Nature (11/01/24) analyzed blood samples from 27 people with long COVID (LC) and 16 fully recovered individuals 8 months after infection. LC participants had persistent symptoms like fatigue and ‘brain fog’. The goal was to deeply characterize immunity and identify unique immune features of LC.
Analysis found LC individuals exhibited systemic inflammation and immune dysregulation. This was shown by global T cell subset differences indicating ongoing immune responses. There were also sex-specific changes in cytolytic T cell subsets.
Compared to recovered individuals, LC participants had more CD4+ T cells poised to migrate to inflamed tissues and more exhausted SARS-CoV-2-specific CD8+ T cells. They also had higher antibody levels but improper coordination between T and B cell responses.
The findings suggest improper communication between cellular and humoral adaptive immunity in LC, which could lead to immune dysregulation, inflammation, and LC symptoms.
In summary, deep immune profiling identified distinct immune signatures and dysregulation in LC patients 8 months after infection compared to recovered individuals. This provides insights into potential mechanisms underlying long COVID.
You can read the full study here.