Dual knockdown of beta-2 microglobulin and class Il major histocompatibility complex transactivator minimizes the immunogenicity of dental pulp stem cells

Abstract

<p><b>Aim of the presentation:</b></p><p>Pulp regeneration is widely considered an optimal treatment for treating devitalised teeth. One</p><p>of the approaches for generating pulp and dentin is to introduce allogeneic dental pulp stem</p><p>cells (DPSCs) into the root canals. However, the long-term survival of DPSCs after</p><p>transplantation has been compromised due to the presence of human leukocyte antigens</p><p>(HLAs), making them less effective. This study aimed to investigate a genetic modification</p><p>strategy to reduce the immunogenicity of DPSCs after transplantation.</p><p><b>Summary of the talk:</b></p><p>Lentiviral particles were used to encode short hairpin (sh) RNAs targeting beta-2 microglobulin</p><p>(B2M) and Class II major histocompatibility complex transactivator (CIITA) to silence HLA class I</p><p>and II, respectively. Western blot, fluorescence, and flow cytometry were performed to assess</p><p>the B2M, CIITA, and HLA expression in DPSCs-shB2M (B2M silenced DPSCs), DPSCs-shCIITA</p><p>(CIITA silenced DPSCs) and DPSCs-shB2M-shCIITA (B2M and CIITA silenced DPSCs) after IFN-γ</p><p>treatment. The self-renewal capacity and pluripotency of genetically modified DPSCs were</p><p>evaluated by CCK8 assay and osteogenic, adipogenic and neurogenic differentiation assay. The</p><p>results revealed that single knockdown of B2M and CIITA downregulated the expression of HLA-I</p><p>and HLA-II, respectively, while dual knockdown resulted in a reduction in both HLA-I and HLA-II.</p><p>The knockdown had no effect on the self-renewal capacity and pluripotency of DPSCs.</p><p><b>Key learning point:</b></p><p>This study demonstrated a novel way of generating low immunogenicity recognisable DPSCs by</p><p>genetic modification, which may potentially increase the success rate of DPSC transplantation</p><p>during pulp regeneration.</p>