used to identify novel CD20 specific CD4+ T cell epitopes relevant in lymphoma immunotherapy
Milcent B., Siberil S. et al, (2019) "Presence of T cells directed against CD20-derived peptides in healthy individuals and lymphoma patients" Cancer Immunology, Immunotherapy
Preclinical and clinical studies have suggested that cancer treatment with antitumor antibodies induces a specific adaptive T cell response. A central role in this process has been attributed to CD4+ T cells. In this study human CD20-derived epitopes restricted by HLA-DR1, HLA-DR3, HLA-DR4, and HLA-DR7 were characterized.
The results from this study indicate that carefully selected CD20-derived MHC II-restricted peptides make it possible to induce CD20-specific CD4+ T cell responses in humanized HLA-DR-transgenic mice and in human PBMCs. These peptides could serve as a therapeutic tool in B cell malignancies to improve the antitumor activity of CD4+ T cells in the context of vaccination strategies by helping CD8+ T cell response and eventually through direct cytotoxic effector functions.
Fig. 1. Screening of immunogenic HLA-DR-restricted CD20-derived peptides. a Cumulative scores of the binding of human CD20-derived peptides to recombinant HLA-DRB1*01:01 (blue), *03:01 (red), *04:01 (green), and *07:01 (purple) molecules as calculated with the ProImmune REVEAL® MHC-peptide binding assay. High scoring peptides within intracellular, transmembrane, and extracellular domains of the human CD20 molecule were pooled into 9 different mixtures of 18 to 20-mer MHC II-restricted peptides (huMHC II_Mix 1 to 9) (see also Supplementary Table 1). b Localization of the different MHC II-restricted CD20-derived peptide mixtures (huMHC II_Mix 1 to 3 in red; huMHC II_Mix 4 in green; huMHC II_Mix 5 in dark blue; huMHC II_Mix 6 to 8 in light blue; huMHC II_Mix 9 in pink)
In vitro MHC peptide-binding assays do what prediction tools can't. They confirm the physical binding characteristics of actual peptides, based on their sequence.
ProImmune is the world leader in providing in vitro MHC peptide binding assays, offering the widest range of MHC alleles and assay options, from high throughput screening to in-depth competition assays between candidate peptides. Our specialist immunology advisory team can help you define your project needs and quickly tailor the most relevant assay solution.
Case Study published by FDA:
Researchers at the US FDA and colleagues use ProImmune REVEAL to understand how immunogenicity of therapeutic Factor VIII protein varies between ethnic groups based on their HLA tissue-type (Pandey G.S. et al. PLOS Computational Biology May 2013, Vol. 9 (5) e1003066):
Figure: (A) Binding scores of FVIII wild type peptides. Binding scores in a REVEAL assay were measured for the synthetic wild type peptides depicted in bold in Table 1. Each row represents a peptide and each column a MHC-II allele. The peptides are grouped together based on the position in the FVIII gene where the haplotypes H2 to H6 occur. Overlapping peptides were used around the position of each ns-SNP. Positive-control (PC) peptides are known T-cell epitopes of FVIII and negative control (NC) peptides are from regions of the FVIII protein where no T-cell epitopes have been identified. The scale for the binding score is shown at the top of the figure; dark colors represent peptides that bind with high affinity to the MHC-II allele. (B) FVIII high affinity binders. Wild type peptides with binding score >15% are shown and considered potential T-cell epitopes for each of the six MHC-II alleles. (C) Binding promiscuity scores for the wild type FVIII peptides. The binding promiscuity score for each peptide, defined as the fraction of MHC-II variants the peptide binds with a score >15%, is shown.
Praise for ProImmune REVEAL
Prof. Julio Delgado University of Utah, USA "The advantage of ProImmune’s in vitro system is that we could characterize binding to each HLA molecule individually and not have to guess which of the range of HLA molecules expressed by our patients was responsible for antigen presentation. "
Dr. Gene Olinger United States Army Medical Research Institute of Infectious Diseases (USAMRIID) "ProImmune accomplished in two months what would have taken three years in our laboratory"
See how Baxter to have used ProImmune REVEAL® to understand the immunogenicity of human Factor VIII treatment:
CD4+ T-cell epitopes associated with antibody responses after intravenously and subcutaneously applied human FVIII in humanized hemophilic E17 HLA-DRB1*15:01 mice Steinitz, K. et al Blood 2012 [PubMedID:22394599]
What will you get?
ProImmune REVAL® data is reported in our detailed reporting templates for this assay range. Reports present data from the particular assays selected.
Figure: REVEAL Class II Example Data Presentation Binding as a percentage of the positive control is shown in green. Red overlay: Stability after 24hrs at 37°C.