Poster Presentation 4th Metabolic Diseases; Breakthrough Discoveries in Diabetes & Obesity Meeting 2024

Identifying Novel C-peptide Specific TCRs For The Development of Antigen-Specific T-Regulatory Cell Therapy for Type 1 Diabetes (#156)

Ashraf AB Broury 1
  1. Subclinical Faculty of Clinical and Molecular Medicine, Monash University, Clayton , VIC, Australia

C-peptide, a byproduct of insulin, has been recently identified as an autoantigen in Type 1 Diabetes (T1D) [1]. Regulatory T cells (Tregs), a subset of CD4+ T cells, possess the crucial ability to suppress overactive immune responses and maintain immune tolerance. Studies in the past, have trialled the use of polyclonal Tregs in hopes to prevent decline in beta cell function, but have not made significant progress [2,3]. However, this research can be built upon by exploiting the suppressive capabilities of Tregs in an autoantigen-specific manner. This study aims to identify novel C-peptide specific TCRs for the development of autoantigen specific Treg therapy against T1D. 

 

Using a proliferation assay composed of isolated CD4+ T cells, mature dendritic cells and C-peptide, CD4+ T cells which have proliferated in response to C-peptide were isolated and sorted by FACS. Sorted cells then underwent 10x single cell sequencing for high throughput single cell genomic data extraction. Using a novel selection technique, activation induced markers [4] were utilised to select TCR clonotypes that derived from cells with an antigen specific profile. Utilising this technique allowed for the identification of 4 novel C-peptide specific TCRs, in addition to 3 novel TCRs identified using a conventional TCR selection process, totalling to 7 novel C-peptide specific TCRs. The newly identified TCRs will then be expressed on human Tregs via lentiviral transduction in the next aim of the parent study where they will be validated for their specificity and functionality against C-peptide and T1D, respectively.

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