For a study, it was determined that a new class of aptamer-based technology could identify over 7,000 analytes per sample, providing a high-throughput alternative to classic immunoassays in biomarker discovery. However, the selectivity for different proteins in the setting of CKD had not been adequately investigated. Using immunoassays as the gold standard, researchers evaluated the application of SOMAscan, an aptamer-based technology, for the measurement of eight immune activation biomarkers and cystatin C in 498 African American Study of Kidney Disease and Hypertension (AASK) participants. They looked at how blood proteins determined by SOMAscan and immunoassays correlated with each other and with iothalamate-measured GFR. Then, they looked at the links between protein levels and the likelihood of incident renal failure and all-cause mortality.
Around 6 biomarkers (IL-8, soluble TNF receptor superfamily member 1B [TNFRSF1B], cystatin C, soluble TNF receptor superfamily member 1A [TNFRSF1A], IL-6, and soluble urokinase-type plasminogen activator receptor [suPAR]) had significant (r=0.94, 0.93, 0.89, 0.85, 0.46, and 0.23, respectively) correlations between SOMAscan and immunoassay. TNFRSF1B, cystatin C, TNFRSF1A, and suPAR were all negatively connected with measured GFR and linked to a greater risk of renal failure among the six biomarkers having non-negligible associations. Both approaches found a link between IL-8, TNFRSF1B, cystatin C, TNFRSF1A, and suPAR with an increased chance of death. Immunoassay measurements were, on average, more strongly linked to negative outcomes than SOMAscan readings.
SOMAscan is a fast and somewhat accurate technology for assessing IL-8, TNFRSF1B, cystatin C, and TNFRSF1A in CKD and identifying their possible correlations with clinical outcomes.