COVID-19 Research

There has been a massive worldwide effort from the scientific, medical and public health communities to understand and fight the COVID-19 pandemic. It is evident that T cells are essential to combat infection with any viral pathogen and monitoring the T-cell responses in COVID-19 is critical to understanding the pandemic dynamics and the efficacy of potential vaccines and treatments. The immunoSEQ® T-MAP™ COVID technology allows researchers to monitor the immunologic response to SARS-CoV-2 and track the response longitudinally over time across various sample types.

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    SARS-CoV-2 variants are escaping neutralizing antibody responses, but have not escaped the T-cell response – A Johnson & Johnson Case Study

    Learn how immunoSEQ T-MAP COVID was used in a recent Nature publication to measure the T-cell immune response, induced by the Ad26.COV2.S COVID-19 vaccine, and quantify T-cell expansion across all regions of the SARS-CoV-2 virus.


Alter et al., Nature, 2021

Immunogenicity of Ad26.COV2.S vaccine against SARS-CoV-2 variants in humans

The Ad26.COV2.S vaccine1,2,3 has demonstrated clinical efficacy against symptomatic COVID-19, including against the B.1.351 variant that is partially resistant to neutralizing antibodies1. However, the immunogenicity of this vaccine in humans against SARS-CoV-2 variants of concern remains unclear. Here we report humoral and cellular immune responses from 20 Ad26.COV2.S vaccinated individuals from the COV1001 phase I–IIa clinical trial2 against the original SARS-CoV-2 strain WA1/2020 as well as against the B.1.1.7, CAL.20C, P.1 and B.1.351 variants of concern. Ad26.COV2.S induced median pseudovirus neutralizing antibody titres that were 5.0-fold and 3.3-fold lower against the B.1.351 and P.1 variants, respectively, as compared with WA1/2020 on day 71 after vaccination. Median binding antibody titres were 2.9-fold and 2.7-fold lower against the B.1.351 and P.1 variants, respectively, as compared with WA1/2020. Antibody-dependent cellular phagocytosis, complement deposition and natural killer cell activation responses were largely preserved against the B.1.351 variant. CD8 and CD4 T cell responses, including central and effector memory responses, were comparable among the WA1/2020, B.1.1.7, B.1.351, P.1 and CAL.20C variants. These data show that neutralizing antibody responses induced by Ad26.COV2.S were reduced against the B.1.351 and P.1 variants, but functional non-neutralizing antibody responses and T cell responses were largely preserved against SARS-CoV-2 variants. These findings have implications for vaccine protection against SARS-CoV-2 variants of concern.


Elyanow et al., MedRxiv, 2021

T-cell receptor sequencing identifies prior SARS-CoV-2 infection and correlates with neutralizing antibody titers and disease severity

Measuring the adaptive immune response to SARS-CoV-2 can enable the assessment of past infection as well as protective immunity and the risk of reinfection. While neutralizing antibody (nAb) titers are one measure of protection, such assays are challenging to perform at a large scale and the longevity of the SARS-CoV-2 nAb response is not fully understood. Here, we apply a T-cell receptor (TCR) sequencing assay that can be performed on a small volume standard blood sample to assess the adaptive T-cell response to SARS-CoV-2 infection. Samples were collected from a cohort of 302 individuals recovered from COVID-19 up to 6 months after infection. Previously published findings in this cohort showed that two commercially available SARS-CoV-2 serologic assays correlate well with nAb testing. We demonstrate that the magnitude of the SARS-CoV-2-specific T-cell response strongly correlates with nAb titer, as well as clinical indicators of disease severity including hospitalization, fever, or difficulty breathing. While the depth and breadth of the T-cell response declines during convalescence, the T-cell signal remains well above background with high sensitivity up to at least 6 months following initial infection. Compared to serology tests detecting binding antibodies to SARS-CoV-2 spike and nucleoprotein, the overall sensitivity of the TCR-based assay across the entire cohort and all timepoints was approximately 5% greater for identifying prior SARS-CoV-2 infection. Notably, the improved performance of T-cell testing compared to serology was most apparent in recovered individuals who were not hospitalized and were sampled beyond 150 days of their initial illness, suggesting that antibody testing may have reduced sensitivity in individuals who experienced less severe COVID-19 illness and at later timepoints. Finally, T-cell testing was able to identify SARS-CoV-2 infection in 68% (55/81) of convalescent samples having nAb titers below the lower limit of detection, as well as 37% (13/35) of samples testing negative by all three antibody assays. These results demonstrate the utility of a TCR-based assay as a scalable, reliable measure of past SARS-CoV-2 infection across a spectrum of disease severity. Additionally, the TCR repertoire may be useful as a surrogate for protective immunity with additive clinical value beyond serologic or nAb testing methods.

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COVID-19 Publication Review

In this review, we focus on lessons learned from COVID-19 research around detecting the virus and immune response, vaccine & drug development, variants and vaccine response, autoimmune disease, and oncology.

immunoSEQ T-MAP COVID Overview Brochure

Ongoing COVID-19 research has established the critical role of T cells in the immune response to SARS-CoV-2. Learn about our immunoSEQ T-MAP COVID offering that can accurately and quantitatively measure the T-cell immune response in COVID-19 clinical trial, vaccine, and drug development research.

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COVID-19 Applications

Learn how immunoSEQ® T-MAP™ COVID can help uncover the T-cell immune response in COVID-19.

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