Medical technology Tracking down the antibodies

Multi-electrode layout for parallel analysis of several cell samples in microfluidic chips.

In the "ViroSens" project, researchers from the Fraunhofer-Gesellschaft in Regensburg and Sulzbach as well as industrial partners are combining electrochemical sensor technology and biotechnology. The aim is to develop an analytical method to test the efficacy of vaccines more efficiently.

Most people see vaccinations as a blessing of modern medicine. After all, they protect against dangerous viral diseases. But before a vaccine can enter the doctor's office, it is first tested for its efficacy. The tests are typically carried out in the laboratory on cultivated cells. First, the blood serum of a previously vaccinated person is introduced into the cell culture, then the test cells are exposed to a virus infection.

If the vaccination was successful, the serum contains sufficient neutralizing antibodies against the viruses and the virus contact has no consequences. If the vaccination was not efficient enough, the antibody titers in the serum are not sufficient to completely intercept the viral load. The cells used for the test are then defenceless against the viruses and become infected. The problem: A possible infection of the test cells is currently being investigated with expensive staining methods, which is increasingly limiting in view of the enormous number of tests required for vaccine development.

Automatically measure the state of infection

Scientists of the Fraunhofer Instituts für Biomedizinische Technik IBMT in Sulzbach/Saar and the Fraunhofer Einrichtung für Mikrosysteme und Festkörpertechnologien EMFT on the campus of the University of Regensburg are currently working together with the companies Nanoanalytics (Münster) and Innome on a new approach for the measurement of antiviral neutralizing antibodies.

For this purpose, the test cells are placed on multi-electrode arrays, which allow their infection status to be recorded fully automatically with electrochemical measuring methods. This eliminates the time-consuming staining reactions of conventional tests, which saves time and money.

The new method has another advantage: The cells are continuously monitored over a longer period of time. With the previously used staining methods, they are only analysed at a specific point in time. This provides the researchers with additional information on the time course of the cell reaction that was not available previously .

The consortium has set itself the goal of researching an appropriate complete system including the measuring device, the associated analysis software and the electrode arrays required for cell observation, and to implement it in laboratory set-ups that pave the way for a later market launch.