They develop a simple test to detect cellular immunity to SARS-CoV2

2021/09/14 Galarraga Aiestaran, Ana - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

The test is like the tuberculin test: Inject part of protein S into the skin and see if there is a reaction. Ed. WikiImages

A simple, cheap skin test has been developed at the University Hospital of the Canary Islands to determine whether the body has produced T lymphocytes with the S protein of SARS-CoV2, either by infection or by vaccination.

In fact, the antibody tests are not enough to measure the degree of immunity, as antibodies eventually disappear on their own. The skin test detects T lymphocytes, the lymphocytes responsible for the formation of antibodies that activate B cells.

The test uses the Mantoux (tuberculin) method: Part of the S protein is injected into the arm and if it has been previously infected or is inserted, T cells respond and the skin becomes red and increases around the puncture site.

Researchers warn that the test is not useful to know the lymphocyte level, it is only possible to know whether it exists or not. But it's cheap and simple, and useful to decide, for example, whether a person needs a third dose of vaccine or not.