With the rise in occurrence of sepsis, it is more important than ever to identify biomarkers that can be used for early detection of severe sepsis. Some researchers have been focusing on the transition that occurs from sepsis (overreaction by the immune system) to severe sepsis (immunosuppression) and the alterations in monocytes and T cells that are characteristic of the immunosuppressive phase of severe sepsis.
Research has determined that circulating monocytes from patients with severe sepsis have decreased amounts of major histocompatibility complex (MHC) class II proteins on their surfaces and circulating T cells have significantly increased CTLA-4 ligand. It is yet to be determined if these facts can translate to useful biomarkers for early identification of severe sepsis. Flow cytometry may be the laboratory method of choice, if changes in circulating monocytes and T cells provide the ideal biomarkers for early detection of severe sepsis.