Targeting the Exon2 splice cis-element in PD-1 and its effects on lymphocyte function.

Area of Science:

• Immunology
• Molecular Biology
• Biotechnology

Background:

• Chimeric antigen receptor (CAR)-T cell therapy shows promise for cancer treatment but faces challenges like insufficient T-cell activation, poor persistence, and genotoxicity.
• Programmed cell death protein 1 (PD-1) negatively regulates T-cell responses by interfering with T-cell receptor signaling, leading to decreased cytokine secretion and proliferation.

Purpose of the Study:

• To investigate the potential of CRISPR/dCas13-mediated RNA editing of PD-1 pre-mRNA to overcome limitations in T-cell therapies.
• To assess the impact of targeting the Exon2 splice cis-element of PD-1 pre-mRNA on T-cell function, specifically cytokine production and proliferation.

Main Methods:

• Utilized CRISPR/dCas13 technology to specifically extract the splice element of PD-1 pre-mRNA in CD8+ T-cell lines.
• Examined the effects of this RNA targeting on cytokine production (IFN-γ, TNF-α, GM-CSF) and cell proliferation.

Main Results:

• Targeting the PD-1 pre-mRNA Exon2 splice cis-element resulted in lower production of IFN-γ, TNF-α, and GM-CSF compared to non-targeted cells.
• Crucially, RNA-targeted cells maintained their overall cytokine secretion capacity and cell proliferation ability.

Conclusions:

• CRISPR/dCas13-based RNA editing of PD-1 pre-mRNA presents a novel strategy to mitigate genotoxicity in T-cells.
• This approach offers a potential method to improve T-cell therapy efficacy by enhancing T-cell persistence and function without compromising essential immune responses.