P129 Flexmap 3d® generates a comparable result for lifecodes® LSA single antigen products with respect to luminex® 200 platform

Abstract

Aim The objective was to demonstrate equivalency of qualitative results among the LIFECODES LSA Single Antigen products performed on two different Luminex Instrument Platforms: The Luminex 200 and the FLEXMAP 3D. Methods For each LIFECODES LSA Single Antigen Assay (LSA 1 and LSA 2), a panel of 32 samples was selected. Samples were chosen based on previously characterized reactivity to either HLA Class I or HLA Class II antigens. For the first incubation of the assay, replicate samples were pooled together (sera + beads) in sufficient volume to be subsequently divided and distributed to the designated wells to be run on the different instrument platforms. This was done to minimize any variation between the replicates that may occur during the initial incubation. For each LSA assay, samples were tested side by side on both the Luminex 200 Instrument and on the FLEXMAP 3D Instrument using the “Standard” reporter gain setting. Because the FLEXMAP 3D produces higher MFI values, an MFI divider was applied to obtain MFI equivalent to the Luminex 200. To identify the appropriate divider, a data simulation was performed by applying a variety of MFI Dividers with values in the range of 1.00 to 2.00. For each MFI Divider simulated, the sum of the MFI values for each sample was compared to the sum of the MFIs for the same sample run on the Luminex 200. A two-tailed T-test was then used to determine which simulated MFI divisor provided the most equivalent data points between the FLEXMAP 3D and LMX200 platforms. In a follow-up experiment, an assay was performed on FLEXMAP 3D by incorporating the most equivalent divider value. Results Over the evaluated MFI divider range of 1.0 to 2.00, a value of 1.67 gave the maximum p-value when compared to data generated by the Luminex 200 Instrument. A 2 × 2 analysis of antigen assignments for LSA1 & LSA2 show an overall concordance of >98% between FLEXMAP 3D (with a divider value of 1.67) and Luminex 200. Conclusions This study with 32 samples suggests that comparable results can be obtained between the Luminex 200 and FLEXMAP 3D instrument platforms when a divider value of 1.67 is applied to the MFIs generated by the FLEXMAP 3D. R. Kumar: 5. Employee; Company/Organization; Immucor. R. Clouse: 5. Employee; Company/Organization; Immucor. B.L. Ray: 5. Employee; Company/Organization; Immucor.