Dynamic changes of neutralizing antibody and memory T cell responses six months post Omicron XBB reinfection

Front Immunol. 2024 Oct 7:15:1477721. doi: 10.3389/fimmu.2024.1477721. eCollection 2024.

Abstract

Introduction: With the continued prevalence of COVID-19, repeated infection caused by SARS-CoV-2 has become common. However, studies on immune persistence post Omicron XBB reinfection are limited.

Methods: We prospectively studied the durability and cross-reactivity of neutralizing antibodies (NAbs) and T cell responses among 20 subjects who suffered Omicron BA.5 infection with or without Omicron XBB reinfection over 6-month through the pseudovirus neutralization test and the fluorospot assay.

Results: NAbs against EG.5.1, BA.2.86, and JN.1 subvariants were decreased and undetectable at 6-month post Omicron BA.5 infection, while those elicited by Omicron XBB reinfection were significant increased and remained detectable against all detected variants within 6-month. Furthermore, in subjects with Omicron XBB reinfection, memory T cell responses could cross-recognized wild-type and Omicron spike peptides and reached peak at 3-month. Interestingly, comparable robust T cell responses were observed among non-seroconverted subjects post Omicron XBB exposure.

Conclusion: Though the NAbs against various emerging Omicron subvariants elicited by Omicron XBB reinfection can persist for at least 6-month, the HCWs should strengthen personal protection and timely be immunized with updated vaccines upon current circulating variants or conserved T epitope.

Keywords: Omicron XBB reinfection; cross-recognition; immune persistence; memory T cell responses; neutralizing antibody.

MeSH terms

  • Adult
  • Antibodies, Neutralizing* / immunology
  • Antibodies, Viral* / blood
  • Antibodies, Viral* / immunology
  • COVID-19 Vaccines / immunology
  • COVID-19* / immunology
  • Cross Reactions / immunology
  • Female
  • Humans
  • Male
  • Memory T Cells* / immunology
  • Middle Aged
  • Prospective Studies
  • Reinfection* / immunology
  • SARS-CoV-2* / immunology
  • Spike Glycoprotein, Coronavirus / immunology

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 Vaccines
  • Spike Glycoprotein, Coronavirus

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by Beijing Natural Science Foundation (L222119 to G-LW), the National Natural Science Foundation of China (82103901 to G-LW) and the State Key Laboratory of Pathogen and Biosecurity (SKLPBS2205 to C-LL) The funders played no role in the study design, collection, analysis, and interpretation of data, in the writing of the manuscript; or in the decision to submit the manuscript for publication.