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Published on: September 7, 2022
B Cell Dynamics and Transitional B Cells in Long COVID
Zoia R Korobova1,2, Natalia A Arsentieva1,2, Natalia E Liubimova1
1Laboratory of Molecular Immunology, Saint Petersburg Pasteur Institute, ul. Mira, 14, 197101 Saint Petersburg, Russia.
Background:
Long COVID is characterized by persistent symptoms following acute SARS-CoV-2 infection. This study aims to evaluate immune system markers, including antigen-specific antibodies, B cell subsets, and Th2-related cytokines, in individuals with long COVID and to investigate their potential impact on the development of this condition.
Methods:
We analyzed blood plasma from 63 individuals diagnosed with long COVID based on clinical presentation and 47 healthy individuals with COVID-19 history but no clinical symptoms. Antigen-specific IgG antibodies were measured using commercial ELISA kits. Lymphocyte subpopulations were assessed via flow cytometry and a gating strategy based on CD27 and CD38. Th2 cytokines (IL-4, IL-5, IL-13) were quantified using the xMAP multiplex assay.
Results:
We noted no significant differences in IgG levels between groups. Notably, individuals with long COVID demonstrated a higher percentage of naive mature B cells (CD27-CD38+), while transitional (CD27-CD38+++) and double-negative (DN, CD27-CD38-) cells were significantly reduced. Elevated levels of IL-5 and IL-13 were observed in long COVID patients. Classification analysis revealed that the percentage of transitional B cells (CD27-CD38+++) was a strong predictor of long COVID.
Conclusions:
Our findings highlight alterations in B cell dynamics among individuals with long COVID, which may contribute to autoimmune processes.
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