Use of induced pluripotent stem cells to investigate the effects of purine nucleoside phosphorylase deficiency on neuronal development

Abstract

Background: Inherited defects in the function of the purine nucleoside phosphorylase (PNP) enzyme can cause severe T cell immune deficiency and early death from infection, autoimmunity, or malignancy. In addition, more than 50% of patients suffer diverse non-infectious neurological complications. However the cause for the neurological abnormalities are not known. Objectives: Differentiate induced pluripotent stem cells (iPSC) from PNP-deficient patients into neuronal cells to better understand the effects of impaired purine metabolism on neuronal development. Methods: Sendai virus was used to generate pluripotent stem cells from PNP-deficient and healthy control lymphoblastoid cells. Cells were differentiated into neuronal cells through the formation of embryoid bodies. Results: After demonstration of pluripotency, normal karyotype, and retention of the PNP deficiency state, iPSC were differentiated into neuronal cells. PNP-deficient neuronal cells had reduced soma and nuclei size in comparison to cells derived from healthy controls. Spontaneous apoptosis, determined by Caspase-3 expression, was increased in PNP-deficient cells. Conclusions: iPSC from PNP-deficient patients can be differentiated into neuronal cells, thereby providing an important tool to study the effects of impaired purine metabolism on neuronal development and potential treatments. Statement of novelty: We report here the first generation and use of neuronal cells derived from induced pluripotent stem cells to model human PNP deficiency, thereby providing an important tool for better understanding and management of this condition.