Personalized iPSC-Derived Dopamine Progenitor Cells for Parkinson's Disease

Abstract

We report the implantation of patient-derived midbrain dopaminergic progenitor cells, differentiated in vitro from autologous induced pluripotent stem cells (iPSCs), in a patient with idiopathic Parkinson's disease. The patient-specific progenitor cells were produced under Good Manufacturing Practice conditions and characterized as having the phenotypic properties of substantia nigra pars compacta neurons; testing in a humanized mouse model (involving peripheral-blood mononuclear cells) indicated an absence of immunogenicity to these cells. The cells were implanted into the putamen (left hemisphere followed by right hemisphere, 6 months apart) of a patient with Parkinson's disease, without the need for immunosuppression. Positron-emission tomography with the use of fluorine-18-L-dihydroxyphenylalanine suggested graft survival. Clinical measures of symptoms of Parkinson's disease after surgery stabilized or improved at 18 to 24 months after implantation. (Funded by the National Institutes of Health and others.).

Figure 1.. Immunogenicity of Midbrain Dopaminergic Progenitor Cells (mDAPs) in Humanized Mice.

Panels A and B show mouse brain sections stained with antibodies against human neural-cell adhesion molecule (hNCAM) (Panel A) and tyrosine hydroxylase (TH) with hNCAM (Panel B) at 2 weeks after transplantation of autologous and allogenic mDAPs, to detect the presence and dopaminergic differentiation of surviving grafts. In Panel B, the bottom row of images depicts magnified areas of the TH images. Panel C shows staining with anti-CD4 antibodies, with major cell loss and T-cell infiltration only in the allogeneic grafts placed in the patient-humanized animals. Cells were counterstained with Hoechst 33342. All scale bars indicate 100 μm. C4-hu denotes an NSG mouse (nonobese diabetic mouse with severe combined immunodeficiency and depletion of the interleukin-2 receptor γ) humanized with patient-derived peripheral-blood mononuclear cells, C4-mDAPs patient-derived mDAPs, H9-mDAPs human embryonic cell line–derived mDAPs, and K1-hu an NSG mouse humanized with volunteer-derived peripheral-blood mononuclear cells.

Figure 2.. Imaging.

Panel A shows axial fluorine-18-L-dihydroxyphenylalanine (¹⁸F-DOPA) positron-emission tomographic images at the level of the basal ganglia at the time points indicated: baseline (4 months before first surgery), 3 months after the left implantation, 12 months after the left implantation and 6 months after the right implantation, and 24 months after the left implantation and 18 months after the right implantation. A decrease in ¹⁸F-DOPA uptake 3 months after the initial left implantation was followed by a modest increase in dopamine uptake on both sides (right greater than left), mainly in the posterior putamen near the graft sites. The table below the images shows the percentage change in ¹⁸F-DOPA uptake (by standardized uptake value [SUV] ratio) with respect to baseline before surgery or to the lowest uptake measured 3 months after the first (left side) implantation, as indicated by the timeline arrows. Anterior and posterior denote the position of the measured region of interest within the putamen. Panel B is a T2-weighted BLADE magnetic resonance image at 18 months after the left implantation and 12 months after the right implantation. Arrows indicate the location of the implants. Hyperintensity on T2-weighted imaging was associated with the graft sites, more prominently on the right.

Figure 3.. Longitudinal Clinical Assessments of Parkinson’s Disease–Related Motor Function and Quality of Life.

Panel A shows scores on the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), part III. Scores (range, 0 to 132, with higher scores indicating worse parkinsonian motor signs) are shown both after overnight withdrawal of levodopa (“off”) and at the peak dose of levodopa (“on”). Panel B shows scores on the 39-item Parkinson’s Disease Questionnaire (PDQ-39) assessing quality of life. Scores range from 0 to 156, with higher scores indicating worse quality of life. In both panels, the dashed line at 6 months indicates the time of the second implantation.