Elevated BMI reduces the humoral response to SARS-CoV-2 infection

Marcus Zw Tong; Julian Dj Sng; Meagan Carney; Lucy Cooper; Samuel Brown; Katie E Lineburg; Keng Yih Chew; Neve Collins; Kirsten Ignacio; Megan Airey; Lucy Burr; Briony A Joyce; Dhilshan Jayasinghe; Christopher Ld McMillan; David A Muller; Anurag Adhikari; Linda A Gallo; Emily S Dorey; Helen L Barrett; Stephanie Gras; Corey Smith; Kim Good-Jacobson; Kirsty R Short

doi:10.1002/cti2.1476

Elevated BMI reduces the humoral response to SARS-CoV-2 infection

Clin Transl Immunology. 2023 Dec 3;12(12):e1476. doi: 10.1002/cti2.1476. eCollection 2023.

Authors

Marcus Zw Tong¹, Julian Dj Sng¹, Meagan Carney², Lucy Cooper^{3

4}, Samuel Brown¹, Katie E Lineburg⁵, Keng Yih Chew¹, Neve Collins¹, Kirsten Ignacio¹, Megan Airey¹, Lucy Burr^{5

6}, Briony A Joyce¹, Dhilshan Jayasinghe^{3

7}, Christopher Ld McMillan^{1

8}, David A Muller^{1

8}, Anurag Adhikari⁷, Linda A Gallo⁹, Emily S Dorey¹⁰, Helen L Barrett^{10

11

12}, Stephanie Gras^{3

7}, Corey Smith⁵, Kim Good-Jacobson^{3

4}, Kirsty R Short^{1

8}

Affiliations

¹ School of Chemistry and Molecular Biosciences The University of Queensland St Lucia QLD Australia.
² School of Mathematics and Physics The University of Queensland St Lucia QLD Australia.
³ Department of Biochemistry and Molecular Biology Monash University Clayton VIC Australia.
⁴ Immunity Program, Biomedicine Discovery Institute Monash University Clayton VIC Australia.
⁵ QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Translational and Human Immunology Laboratory, Infection and Inflammation Program QIMR Berghofer Medical Research Institute Herston QLD Australia.
⁶ Department of Respiratory Medicine Mater Health Brisbane QLD Australia.
⁷ Department of Biochemistry and Chemistry La Trobe Institute for Molecular Science, La Trobe University Bundoora VIC Australia.
⁸ Australian Infectious Diseases Research Centre The University of Queensland St Lucia QLD Australia.
⁹ School of Health University of the Sunshine Coast Petrie QLD Australia.
¹⁰ Mater Research The University of Queensland South Brisbane QLD Australia.
¹¹ University of New South Wales Medicine Kensington NSW Australia.
¹² Obstetric Medicine Royal Hospital for Women Randwick NSW Australia.

Abstract

Objective: Class III obesity (body mass index [BMI] ≥ 40 kg m^-2) significantly impairs the immune response to SARS-CoV-2 vaccination. However, the effect of an elevated BMI (≥ 25 kg m^-2) on humoral immunity to SARS-CoV-2 infection and COVID-19 vaccination remains unclear.

Methods: We collected blood samples from people who recovered from SARS-CoV-2 infection approximately 3 and 13 months of post-infection (noting that these individuals were not exposed to SARS-CoV-2 or vaccinated in the interim). We also collected blood samples from people approximately 5 months of post-second dose COVID-19 vaccination (the majority of whom did not have a prior SARS-CoV-2 infection). We measured their humoral responses to SARS-CoV-2, grouping individuals based on a BMI greater or less than 25 kg m^-2.

Results: Here, we show that an increased BMI (≥ 25 kg m^-2), when accounting for age and sex differences, is associated with reduced antibody responses after SARS-CoV-2 infection. At 3 months of post-infection, an elevated BMI was associated with reduced antibody titres. At 13 months of post-infection, an elevated BMI was associated with reduced antibody avidity and a reduced percentage of spike-positive B cells. In contrast, no significant association was noted between a BMI ≥ 25 kg m^-2 and humoral immunity to SARS-CoV-2 at 5 months of post-secondary vaccination.

Conclusions: Taken together, these data showed that elevated BMI is associated with an impaired humoral immune response to SARS-CoV-2 infection. The impairment of infection-induced immunity in individuals with a BMI ≥ 25 kg m^-2 suggests an added impetus for vaccination rather than relying on infection-induced immunity.

Keywords: BMI; SARS‐CoV‐2; antibody immunity; obesity; overweight.