Blood infections pose particular challenges for clinical diagnostics, as disease progression is determined not only by the pathogen itself but, crucially, by the individual immune response. RamanProImmun is developing a Raman spectroscopy–based test method that, for the first time, reliably distinguishes whether the immune system is overreacting or underreacting in the course of a bacterial infection—thereby addressing a diagnostic gap that cannot be closed by established methods.

At the core of the approach is the analysis of T cells after contact with patient-derived bacteria. Their molecular composition is recorded using Raman spectroscopy and evaluated as a characteristic “spectral fingerprint.” These signatures allow robust conclusions to be drawn about the functional immune status.

For practical application, a compact and portable measurement system is being developed that combines automated cell detection with high-throughput capability and is easy to operate. RamanProImmun thus provides the basis for a more differentiated assessment of blood infections, supports individually tailored therapeutic decisions, and delivers additional insights for microbiological diagnostics.

The RamanProImmun project is funded by the Federal Ministry of Research, Technology and Space under grant number 13GW0836A.