The QuickSwitch Quant HLA-A*02:01 Tetramer Kit can be used for determining the biological activity of a cancer vaccine.

Abstract

We have devised a fast and user-friendly assay (QuickSwitch™ Quant) that can both help determine binding of novel peptides to MHC class I molecules and generate new specificity MHC class I tetramers for peptide specific T cell detection. This study aimed to determine whether the QuickSwitch™ Quant HLA-A*02:01 Tetramer Kit can also be used for evaluating the biological activity of a vaccine. The tested vaccine was DPX-Survivac, an ovarian cancer vaccine candidate which consists of several survivin peptide antigens that are each restricted to a different human class I allele. We sought to evaluate the specificity and sensitivity of the QuickSwitch™ Quant HLA-A* 02:01 Tetramer Kit-PE for assessing the biological activity of SurA2.M, an HLA-A2-restricted peptide, in DPX-Survivac. The complete vaccine also contains non-HLA-A2 restricted peptides, lipids and a polynucleotide adjuvant. We tested the detection of the peptide prepared individually in a buffered solution or in the DPX-Survivac vaccine prepared in an aqueous formulation. Results indicate that peptide exchange rate of SurA2.M is similar whether it is dissolved individually in a buffered solution or mixed with other components of the vaccine. Results also may be dependent on the affinity of the peptide for HLA-A2. Thus, by optimizing a concentration curve using individual peptides, the QuickSwitch™ Quant HLA-A*02:01 Tetramer Kit can be used to quantify the concentration of HLA-A2 restricted peptides in simple solutions or more complex formulations.