Technical Note: Comparison of Alinity c Hemoglobin A1c Immunoassay with Premier Hb9210 Automated HPLC Assay: A Preliminary Report.

OBJECTIVE: We utilized Premier Hb9210 analyzer (HPLC method; Trinity Biotech, Jamestown, NY) for measuring HBA1c in whole blood. As our laboratory is transitioning to Abbott system, we compared HbA1c values obtained by Alinity c and Premier Hb9210. METHODS: The Premier Hb9210 analyzer is based on boronate affinity high performance liquid chromatography with analytical measurement range of 3.8 to 18.5%. The Alinity c Hemoglobin A1c assay measured both total hemoglobin and HbA1c (enzymatic assay) in whole blood and then calculated %HbA1c. The analytical measurement range of this assay is 4 to 14% of HbA1c. We evaluated the analytical performance of Alinity c HbA1c by evaluating precision and also comparing 77 clinical samples with our reference HPLC method. RESULTS: Both Alinity c HbA1c and Premier HB9210 have excellent total precision. Plotting HbA1c results obtained by the Premier Hb9210 analyzer in the x-axis (currently used reference method) and the corresponding values obtained by the Alinity c assay, we observed the following regression equation: y=0.9473x+0.1548 ( n=77, r=0.99). DISCUSSION: Our result indicates that HbA1c enzymatic assay on the Alinity c analyzer showed values comparable to HPLC method. However, at the decision points (2.8% average negative bias at >6.4% and 3.3% average negative bias at 7%), HbA1c values obtained by the Alinity c analyzer were lower than the reference method. CONCLUSIONS: We conclude that HbA1c assay on the Alinity c analyzer is a viable alternative to HPLC for measuring HbA1c in clinical laboratories but values at the decision points must be interpreted with caution and if necessary should be repeated by a reference HPLC method.

Differentiation of human pluripotent stem cells to cells similar to cord-blood endothelial colony-forming cells.

The ability to differentiate human pluripotent stem cells into endothelial cells with properties of cord-blood endothelial colony-forming cells (CB-ECFCs) may enable the derivation of clinically relevant numbers of highly proliferative blood vessel-forming cells to restore endothelial function in patients with vascular disease. We describe a protocol to convert human induced pluripotent stem cells (hiPSCs) or embryonic stem cells (hESCs) into cells similar to CB-ECFCs at an efficiency of >10(8) ECFCs produced from each starting pluripotent stem cell. The CB-ECFC-like cells display a stable endothelial phenotype with high clonal proliferative potential and the capacity to form human vessels in mice and to repair the ischemic mouse retina and limb, and they lack teratoma formation potential. We identify Neuropilin-1 (NRP-1)-mediated activation of KDR signaling through VEGF165 as a critical mechanism for the emergence and maintenance of CB-ECFC-like cells.