T cells vs antibodies
Antibodies are known as the first line of viral defense working to block a virus from infecting a cell. But antibodies can be evaded when viruses mutate (and antibodies can dissipate with time). The most recent example being from COVID-19 variants – such as Omicron – known to not always elicit a reaction from antibodies. But if this is the case why are some infected individuals getting seriously ill? The answer may be in their T cells.
A strong T-cell response is essential to a wide variety of immune functions, including defense against viral infections, vaccine effectiveness, autoimmune disease and healthy aging. “Without good T cells, you get allergies, you get autoimmune disease, your vaccination is not successful, and you can’t combat microorganisms like tuberculosis,” she says.
König approaches the study of T cells from multiple angles. At Magdeburg Molecular Detection, a molecular research, testing and diagnostic company she founded, her team has been monitoring the T-cell responses of patients based on samples, taken from about 4,000 people so far, who have an infection of some kind, including SARS-CoV-2.
“If you have to handle 200–300 samples in one day, you must look for reliable assays that with very fast results. QIAGEN’s was the ideal one,” she says. “We can assay several hundreds a day and get really good results.”
In December 2021, as Omicron variant cases were exploding, “we wanted to research a T-cell test on people facing vaccination choices: People who wanted to find out whether they are already infected, whether they are protected, or whether they should be vaccinated quickly,” she says.
The test they used was QIAGEN’s QuantiFERON SARS-CoV-2 RUO assay, which provides qualitative detection of IFN-gamma produced by CD4+ and CD8+ T-cell responses to SARS-CoV-2 peptides.