Monitoring of cellular immune response against SARS-CoV-2 infection

The OX40 assay can be applied to the study of the immune response mediated through CD4 T-cells after contact with pathogens, such as SARS-CoV-2, and contribute to an immune-competence evaluation in healthy and infected individuals.

The usefulness of antibody tests as a diagnostic method is limited given that their sensitivity in the first week post-infection is low, but they are key for seroprevalence and immunization studies. The absence or lowering of antibody levels cannot be considered as a lack of immunity since it is possible to generate immune memory with T (cellular) and B (humoral) lymphocytes. The CD4 antigen-specific memory T-cells are activated with renewed contact with the antigen within the organism. This subpopulation can be detected with the Act-T4 CellTM kit and the use of specific viral proteins for incubation.

Check out our last webinar

In this webinar, you will learn about the preliminary experience of an Immunology laboratory in the setting-up the OX40 assay for the identification CD4+ T cell specific responses to SARS-CoV-2 peptides, together with its ongoing application to determine the extent and characteristics of the response to natural infection and vaccination.

Capabilities of the flow cytometric OX40 assay to
determine specific SARS-CoV-2 T cell responses

Eduardo López-Granados, MD, PhD
Luz Yadira Bravo Gallego, MD
La Paz University Hospital, Madrid

Antibody panels and characteristics

Act-T4 Cell­™ kit

FITC PE PerCP-Cyanine5.5 APC
CD4 CD134 CD3 CD25

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  1. Zaunders J, et al. High levels of human antigen-specific CD4+ T cells in peripheral blood revealed by stimulated coexpression of CD25 and CD134 (OX40). The Journal of Immunology. 2019 Aug; 183(4):2827-36. Go to publication
  2. Phetsouphanh C, et al. Detecting Antigen-Specific T Cell Responses: From Bulk Populations to Single Cells. International Journal of Molecular Sciences. 2015 Aug; 16(8):18878-93. Go to publication