Establishment of an Enzyme-linked Immunosorbent Assay for the Recognition of Procalcitonin Variants and Characterization of Procalcitonin Variants in Patients With Hyperprocalcitonemia.

Procalcitonin is a protein consisting of 116 amino-acids which can rapidly rise under inflammatory conditions and sepsis. More than 20 years ago it has been shown that dipeptidylpeptidase-4 (DPP-4) cleaves procalcitonin from the n-terminus, resulting in a truncated procalcitonin-variant which consists of 114 aminoacids.

Within their workgroup the investigators found that the truncated procalcitonin-variant had deleterious effects on vascular integrity during sepsis in mice: They observed that binding of truncated procalcitonin to the CRLR/RAMP1-receptor on vascular endothelium lead to phosphorylation and destruction of VE-cadherin, an essential part of adherens junctions. Consequently, paracellular leakage of proteins and fluid from blood vessels developed.

It is unknown if these effects also apply to humans. By using an ELISA-assay the investigators want to examine the ratio between native and truncated human procalcitonin during diseases accompanied with hyperprocalcitoninemia and correlate the results with clinical data. Futhermore, they want to examine if the procalcitonin-variants have influence on cytokine levels and surface antigens on immune cells by performing multiplex immunoassays and FACS-analysis.