Immunoluminometric Assay (ILMA) for the determination of Proenkephalin 119-159 (penKid) in human EDTA plasma
Enkephalin and Proenkephalin119-159 (penKid)
penKid is a stable mid-regional fragment of Proenkephalin and has been established as a surrogate plasma marker for the instable Enkephalin peptides that are derived from the same precursor . Enkephalins are endogenous pentapeptides that are involved in various physiological processes. Enkephalin and its receptors are highly abundant in the kidney .
The plasma concentration of penKid is strongly correlated with kidney function and suitable for timely monitoring of the actual kidney status in several acute diseases and, in contrast to most other kidney markers, unaffected by inflammation  .
Biomarker for the Early Diagnosis and Prediction of Acute Kidney Injury & Monitoring of the Actual Kidney Status
penKid is associated with the severity of Acute Kidney Injury, while unaffected by systemic inflammation. penKid levels are in normal range in septic patients without kidney dysfunction, in contrast to most other kidney markers.
sphingotest® penKid is an immunoluminometric assay (ILMA) for the determination of Proenkephalin119-159 (penKid) in human EDTA plasma. Two antigen-specific monoclonal antibodies are used, which bind penKid (antigen) at two different epitopes. One of the antibodies is luminescent-labelled (tracer antibody), the other is immobilized on the inside of the microtiter plate wells (capture antibody).
 Denning et al. (2008) Peptides. 29(1):83-92.
 Ng et al. (2014) J. Am. Coll. Cardiol. 63(3):280-289.
 Marino et al. (2015) J. Nephrol. 28(6): 717-24.
 Shah et al. (2015) Clinical Nephrology. 83(1):29-35.