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Published on: June 5, 2021
Antibody Course and Memory B-Cell Response in the First Year After Severe Acute Respiratory Syndrome Coronavirus 2
Judith Kannenberg1, Henning Trawinski2, Reinhard Henschler3
1Institute for Medical Microbiology and Virology, University Hospital and Medical Faculty, University of Leipzig, Leipzig, Germany.
Background:
The possibility of repeat infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raises questions regarding quality and longevity of the virus-induced immune response.
Methods:
The antibody course and memory B-cell (MBC) response against SARS-CoV-2 proteins, influenza virus nucleoprotein (NP), and tetanus toxin were examined in adults with mild to moderate SARS-CoV-2 infection in the first year after infection.
Results:
The concentration of SARS-CoV-2 receptor binding domain (RBD)-specific antibodies was low compared with the concentration of influenza virus NP-specific antibodies. The SARS-CoV-2 RBD antibody half-life increased from 95 days in the first 6 months to 781 days after 9-12 months. The SARS-CoV-2 NP antibody half-life increased from 88 to 248 days. Two thirds of the subjects had SARS-CoV-2-specific MBC responses 12 months after infection. The SARS-CoV-2 antibody levels correlated with the MBC frequency at 12 months.
Conclusions:
The low concentration of SARS-CoV-2 spike protein antibodies indicates that re-exposure to the virus or vaccination are required to use the B-cell immunity to full capacity. The existence of a robust SARS-CoV-2 MBC response at 12 months in most subjects and the substantially increasing antibody half-life provide evidence that the immune response is developing into long-term immunity. The early antibody reaction and the ensuing MBC response are interdependent.
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