Standardization of anti-HLA antibody detection assays
Anti-HLA Class I and Anti-HLA Class II Control antibodies are chimeric human IgG monoclonal antibodies validated to recognize class I HLA antigens and class II HLA antigens, respectively [1].
In histocompatibility laboratories, the quantification of anti-HLA antibodies using solid-phase techniques such as LABScreen® or LIFECODES HLA Luminex® assays poses a challenge: the use of subjective MFI cut-off values that do not take into account the run-to-run and bead-to-bead variations.
Traditionally, this problem has been addressed by using pooled human sera from poly-immunized patients for reference calibrations. However, this approach has major limitations, including a lack of a homogeneous signal as a function of HLA antigens, limited stock, and the impossibility to compare results from different laboratories.
InvivoGen together with Professor Antoine Blancher (Histocompatibility and Immunogenetics Laboratory, Toulouse University Hospital) has developed a novel method for standardization of HLA-antibody quantification.
It is based on our proprietary anti-HLA control antibodies, which enable accurate interpretation of mean fluorescence intensity (MFI) values in Luminex® assays.
This step is crucial for patient follow-up studies and for the identification of weak antibodies from highly sensitized patients awaiting organ transplantation.
InvivoGen’s innovative (WO 2013/121157) anti-HLA Class I and anti-HLA Class II positive-control IgG1 antibodies are specifically designed for standardization and calibration in any anti-HLA antibody detection assay, including LABScreen® or LIFECODES HLA multiplex-based assays, ELISAs and flow cytometry.
These control antibodies are available as 100 μg powder to be diluted in albumin buffer for fine standardization or in a ready-to-use kit pre-diluted in its buffer at 3 chosen concentrations (low, medium, and high MFI) for direct use with Luminex®.
Reference:
1. Congy-Jolivet N. et al., 2013. Production and characterization of chimeric anti-HLA monoclonal antibodies targeting public epitopes as tools for standardizations of the anti-HLA antibody detection. J Immunol Methods, 390(1-2):41-51