An enhanced knowledge of how T cell-mediated immunity is established and maintained at the clonal level may inform strategies for improved vaccine and immunotherapy protocols. The identification of antigen-specific T cells could form the basis for diagnostic, prognostic and disease-monitoring tools for immune-mediated disorders. Combining next-generation sequencing and immune assay, Creative Biolabs is proud to introduce our antigen-specific T cells identification service to our clients.
There are a lot of progress in immune monitoring techniques in the past decade, and a series of immune assays can be used to monitor antigen-specific T cell responses. Despite these advances, current immune assays are limited by their sensitivity and inability to discriminate the component T cells, or clonotypes, which contribute to immune responses. Several immune assays have been developed to study the T cell response in an individual, particularly in the context of disease and treatment. Assays, such as ELISPOT, intracellular cytokine staining, and proliferation assays, monitor antigen-specific T cells based on detection of activation following stimulation of the T cells in vitro with antigen. The standard method to monitor antigen-specific T cells is the use of direct multimer staining, but this requires the laborious development of specific HLA-restricted reagents. Immune assays have contributed a lot to our understanding of immune responses. However, many of these methods turn to be with low sensitivity. Next-generation sequencing (NGS) has emerged as a highly sensitive method for characterization of the immune repertoire. Individual clonotypes can be identified based on their unique T cell receptor rearrangements. However, it is limited in its ability to identify clonotypes with specific reactivity to a particular antigen.
Fig.1 Antigen-specific T cell responses are initiated through the interaction of TCR, expressed on T cells, and the corresponding peptide-MHC protein complex expressed by antigen-presenting cells (Newell & Davis 2014).
Creative Biolabs has developed a highly sensitive and quantitative method to identify antigen-specific T cells with high-resolution by combining the tremendous throughput of the sequencing approach with the functional information provided by the immune assays. Our method relies on high-throughput sequencing of the TCR β chain repertoire on our Magic™ TCR repertoire analysis platform. These sequences are analyzed to determine similar sequences that form a clonotype, whose frequency can be determined by the number of member reads. These unique clonotypes and their frequencies can then be tracked from an individual over time. Antigen-specific T cells were identified using a variety of assays: pentamer binding, cell surface marker upregulation following short-term peptide incubation, and proliferation following relatively long-term peptide incubation. In this method, immune assays provide qualitative antigen-specific information, while sequencing reveals the individual clonotypes that contribute to an immune response with great sensitivity.
Key advantages including but not limited to:
Scientists of Creative Biolabs have demonstrated the robustness of our method, and have highlighted the fact that sequencing can be effectively combined with multiple immune assays for identification of antigen-specific T cells. We are pleased to offer the best service with the most accurate results for our global customers.
For more detailed information, please feel free to contact us or directly send us an inquiry.