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. 2024 Mar 8;14(1):5758.
doi: 10.1038/s41598-024-54922-z.

Comparing population-level humoral and cellular immunity to SARS-Cov-2 in Bangalore, India

Anup Malani  1 , Jayashree Aiyar  2 , Andrea Sant  3 , Neha Kamran  2 , Manoj Mohanan  4 , Saloni Taneja  5 , Bartek Woda  6   7 , Wanran Zhao  6 , Anu Acharya  8
Affiliations

Comparing population-level humoral and cellular immunity to SARS-Cov-2 in Bangalore, India

Anup Malani et al. Sci Rep. .

Abstract

Two types of immunity, humoral and cellular, offer protection against COVID. Humoral protection, contributed by circulating neutralizing antibodies, can provide immediate protection but decays more quickly than cellular immunity and can lose effectiveness in the face of mutation and drift in the SARS-CoV-2 spike protein. Therefore, population-level seroprevalence surveys used to estimate population-level immunity may underestimate the degree to which a population is protected against COVID. In early 2021, before India began its vaccination campaign, we tested for humoral and cellular immunity to SARS-Cov-2 in representative samples of slum and non-slum populations in Bangalore, India. We found that 29.7% of samples (unweighted) had IgG antibodies to the spike protein and 15.5% had neutralizing antibodies, but at up to 46% showed evidence of cellular immunity. We also find that prevalence of cellular immunity is significantly higher in slums than in non-slums. These findings suggest (1) that a significantly larger proportion of the population in Bangalore, India, had cellular immunity to SARS-CoV-2 than had humoral immunity, as measured by serological surveys, and (2) that low socio-economic status communities display higher frequency of cellular immunity, likely because of greater exposure to infection due to population density.

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Conflict of interest statement

AM reports consulting for the World Bank, the Asian Development Bank, and IDFC Institute (under a Rockefeller Foundation grant) during this study and conducting seroprevalence studies or training in locations other than Bangalore during the time of this study. The remaining authors report no potential or actual conflicts of interest.

Figures

Figure 1
Figure 1
CONSORT diagram.
Figure 2
Figure 2
Differences in IFN-g and in IL-2 concentrations when sample is stimulated, by humoral immunity test results. Note. Units are pg/ml. Box shows median (with a line) and 25th and 75th percentiles. Whiskers show adjacent values.
Figure 3
Figure 3
Mean positivity rates and 95% confidence intervals for IFN-g and IL-2 fopr subsamples based on results of humoral immunity tests. Note. Dots indicate positivity of cytokine indicated in subplot title and subsample indicated in the row. For example, ELISA+ means subsample that is positive on ELISA and NAB- means negative on nutralizing antibody test. Whiskers indicate 95% confidence intervals for positivity rate for a cytokine assay.
Figure 4
Figure 4
Mean positivity rates and 95% confidence intervals for IFN-g and IL-2 across age and sex. Note. Average positivity rates in unweighted sample, indicated by dashed lines, are .33(ELISA), .15(NAB), .29(IFN-g) and .37(IL-2).
See this image and copyright information in PMC

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References

    1. McMahan K, et al. Correlates of protection against SARS-CoV-2 in rhesus macaques. Nature. 2021;590:630–634. doi: 10.1038/s41586-020-03041-6. - DOI - PMC - PubMed
    1. Le Bert N, et al. SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls. Nature. 2020;584:457–462. doi: 10.1038/s41586-020-2550-z. - DOI - PubMed
    1. Sette A, Crotty S. Adaptive immunity to SARS-CoV-2 and COVID-19. Cell. 2021;184:861–880. doi: 10.1016/j.cell.2021.01.007. - DOI - PMC - PubMed
    1. Feng C, et al. Protective humoral and cellular immune responses to SARS-CoV-2 persist up to 1 year after recovery. Nat. Commun. 2021;12:4984. doi: 10.1038/s41467-021-25312-0. - DOI - PMC - PubMed
    1. Björkander S, et al. SARS-CoV-2–specific B- and T-cell immunity in a population-based study of young Swedish adults. J. Allergy Clin. Immunol. 2022;149:65–75.e68. doi: 10.1016/j.jaci.2021.10.014. - DOI - PMC - PubMed

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