Characterizing the Immunogenicity of Islet-like Cells derived from HLA-edited Human Pluripotent Stem Cells

Although there is much hope for the therapeutic use of islet-like cells generated from human pluripotent stem cells, important challenges limit the clinical translation of this technology. In this thesis, I describe my efforts to address two of these challenges: the inability to control the composition of the islet-like cells generated, and the susceptibility of stem cell-derived islets to allorejection. I first describe methods to improve differentiation into cells bearing the successive phenotypes of primitive streak, definitive endoderm, and pancreatic progenitors. I next explore mechanisms that regulate the endocrine composition of human pluripotent stem cell-derived islets, finding that events both prior to and concurrent with endocrine commitment have important lineage-modulating effects. With these findings, I develop strategies to generate islet-like cells enriched for islet-like (ISL1+) or enterochromaffin-like (ISL1-SLC18A1+) cells. Finally, I leverage these new protocols to study how HLA proteins affect the immunogenicity of human pluripotent stem cell-derived islets. Using human pluripotent stem cells edited to lack cell-surface expression of class I and class II HLA complexes, which retain the ability to generate islet-like cells with insulin-secreting functionality, I find that CD8+ and CD4+ T cell allorecognition requires the presence of cell-surface HLA. Importantly, islet-like cells generated from HLA-edited human pluripotent stem cells demonstrate the potential to evade antibody-mediated rejection in vitro and T cell-mediated rejection in vitro and in vivo. These findings could be used to inform the development of new methods to generate islet-like cells more efficiently and safely for the treatment of type I diabetes.

Department dc:contributor.department

Physiology

Year dc:date.issued

2024

Author dc:creator

• Misra, Paraish Shivam

Advisors dc:contributor.advisor

• Nostro, M. Cristina
• Yuen, Darren A

• Allorejection
• Diabetes
• Insulin
• Islets
• Pluripotent stem cells
• Transplantation

Statement dc:rights

• Attribution-NonCommercial 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc/4.0/

Handle dc:identifier.uri

https://hdl.handle.net/1807/149618

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/149618