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PURPOSE: To report long-term results from a phase 1/2a clinical trial assessment of a scaffold-based human embryonic stem cell-derived retinal pigmented epithelium (RPE) implant in patients with advanced geographic atrophy (GA). DESIGN: A single-arm, open-label phase 1/2a clinical trial approved by the United States Food and Drug Administration. PARTICIPANTS: Patients were 69-85 years of age at the time of enrollment and were legally blind in the treated eye (best-corrected visual acuity [BCVA], ≤ 20/200) as a result of GA involving the fovea. METHODS: The clinical trial enrolled 16 patients, 15 of whom underwent implantation successfully. The implant was administered to the worse-seeing eye with the use of a custom subretinal insertion device. The companion nonimplanted eye served as the control. The primary endpoint was at 1 year; thereafter, patients were followed up at least yearly. MAIN OUTCOME MEASURES: Safety was the primary endpoint of the study. The occurrence and frequency of adverse events (AEs) were determined by scheduled eye examinations, including measurement of BCVA and intraocular pressure and multimodal imaging. Serum antibody titers were collected to monitor systemic humoral immune responses to the implanted cells. RESULTS: At a median follow-up of 3 years, fundus photography revealed no migration of the implant. No unanticipated, severe, implant-related AEs occurred, and the most common anticipated severe AE (severe retinal hemorrhage) was eliminated in the second cohort (9 patients) through improved intraoperative hemostasis. Nonsevere, transient retinal hemorrhages were noted either during or after surgery in all patients as anticipated for a subretinal surgical procedure. Throughout the median 3-year follow-up, results show that implanted eyes were more likely to improve by > 5 letters of BCVA and were less likely to worsen by > 5 letters compared with nonimplanted eyes. CONCLUSIONS: This report details the long-term follow-up of patients with GA to receive a scaffold-based stem cell-derived bioengineered RPE implant. Results show that the implant, at a median 3-year follow-up, is safe and well tolerated in patients with advanced dry age-related macular degeneration. The safety profile, along with the early indication of efficacy, warrants further clinical evaluation of this novel approach for the treatment of GA. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Atrofia Geográfica , Epitelio Pigmentado de la Retina , Agudeza Visual , Humanos , Atrofia Geográfica/cirugía , Atrofia Geográfica/fisiopatología , Epitelio Pigmentado de la Retina/trasplante , Epitelio Pigmentado de la Retina/patología , Anciano , Agudeza Visual/fisiología , Femenino , Anciano de 80 o más Años , Masculino , Estudios de Seguimiento , Tomografía de Coherencia Óptica , Células Madre Embrionarias Humanas/trasplante , Células Madre Embrionarias Humanas/citología , Trasplante de Células Madre , Resultado del TratamientoRESUMEN
Age-related macular degeneration (AMD), a leading cause of vision loss, primarily arises from the degeneration of retinal pigment epithelium (RPE) and photoreceptors. Current therapeutic options for dry AMD are limited. Encouragingly, cultured RPE cells on parylene-based biomimetic Bruch's membrane demonstrate characteristics akin to the native RPE layer. In this study, we cultivated human embryonic stem cell-derived polarized RPE (hESC-PRPE) cells on parylene membranes at both small- and large-scale settings, collecting conditioned supernatant, denoted as PRPE-SF. We conducted a comprehensive analysis of the morphology of the cultured hESC-RPE cells and the secreted growth factors in PRPE-SF. To evaluate the in vivo efficacy of these products, the product was administered via intravitreal injections of PRPE-SF in immunodeficient Royal College of Surgeons (iRCS) rats, a model for retinal degeneration. Our study not only demonstrated the scalability of PRPE-SF production while maintaining RPE cell phenotype but also showed consistent protein concentrations between small- and large-scale batches. We consistently identified 10 key factors in PRPE-SF, including BMP-7, IGFBP-2, IGFBP-3, IGFBP-4, IGFBP-6, MANF, PEDF, PDGF-AA, TGFß1, and VEGF. Following intravitreal administration of PRPE-SF, we observed a significant increase in the thickness of the outer nuclear layer (ONL) and photoreceptor preservation in iRCS rats. Furthermore, correlation analysis revealed that IGFBP-3, IGFBP-4, MANF, PEDF, and TGFß1 displayed positive associations with in vivo bioactivity, while GDF-15 exhibited a negative correlation. Overall, this study highlights the feasibility of scaling up PRPE-SF production on parylene membranes without compromising its essential constituents. The outcomes of PRPE-SF administration in an animal model of retinal degeneration present substantial potential for photoreceptor preservation. Moreover, the identification of candidate surrogate potency markers, showing strong positive associations with in vivo bioactivity, lays a solid foundation for the development of a promising therapeutic intervention for retinal degenerative diseases.
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Polímeros , Degeneración Retiniana , Epitelio Pigmentado de la Retina , Xilenos , Humanos , Animales , Ratas , Epitelio Pigmentado de la Retina/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina , Degeneración Retiniana/metabolismoRESUMEN
The goal of this study was to quantitatively assess retinal thickness using spectral domain optical coherence tomography (SD-OCT) after subretinal implantation of human embryonic stem cell-derived retinal pigment epithelium in a porcine model. The implant is called CPCB-RPE1 for the California Project to Cure Blindness-Retinal Pigment Epithelium 1. Data were derived from previous experiments on 14 minipigs that received either subretinal implantation of CPCB-RPE1 (n = 11) or subretinal bleb formation alone (sham; n = 3) using previously described methods and procedures (Brant Fernandes et al. Ophthalmic Surg Lasers Imaging Retina 47:342-51, 2016; Martynova et al. (2016) Koss et al. Graefes Arch Clin Exp Ophthalmol 254:1553-65, 2016; Hu et al. Ophthalmic Res 48:186-91, 2016; Martynova et al. ARVO Abstract 2016. SD-OCT retinal thickness (RT) and sublayer thickness over the implant were compared with topographically similar preimplantation regions as described previously Martynova et al. ARVO Abstract 2016. Imaging results were compared to postmortem histology using hematoxylin-eosin staining. RT overlying the CPCB-RPE1 postimplantation was not significantly different from preimplantation (308 ± 72 µm vs 292 ± 41 µm; p = 0.44). RT was not significantly different before and after implantation in any retinal sublayer at 1 month. Histology demonstrated grossly normal retinal anatomy as well as photoreceptor interdigitation with RPE.
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Células Madre Embrionarias Humanas/trasplante , Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/citología , Tomografía de Coherencia Óptica , Animales , California , Humanos , PorcinosRESUMEN
Sessions included an overview of past cell therapy (CT) conferences sponsored by the International Alliance for Biological Standardization (IABS). The sessions highlighted challenges in the field of human pluripotent stem cells (hPSCs) and also addressed specific points on manufacturing, bioanalytics and comparability, tumorigenicity testing, storage, and shipping. Panel discussions complemented the presentations. The conference concluded that a range of new standardization groups is emerging that could help the field, but ways must be found to ensure that these efforts are coordinated. In addition, there are opportunities for regulatory convergence starting with a gap analysis of existing guidelines to determine what might be missing and what issues might be creating divergence. More specific global regulatory guidance, preferably from WHO, would be welcome. IABS and the California Institute for Regenerative Medicine (CIRM) will explore with stakeholders the development of a practical and innovative road map to support early CT product (CTP) developers.
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Tratamiento Basado en Trasplante de Células y Tejidos , Células Madre Pluripotentes , Pruebas de Carcinogenicidad , Guías como Asunto , Humanos , Control de Calidad , Medicina RegenerativaRESUMEN
BACKGROUND: Telomerase activity in leukemic blasts frequently is increased among patients with high-risk acute myeloid leukemia (AML). In the current study, the authors evaluated the feasibility, safety, immunogenicity, and therapeutic potential of human telomerase reverse transcriptase (hTERT)-expressing autologous dendritic cells (hTERT-DCs) in adult patients with AML. METHODS: hTERT-DCs were produced from patient-specific leukapheresis, electroporated with an mRNA-encoding hTERT and a lysosomal-targeting sequence, and cryopreserved. A total of 22 patients with a median age of 58 years (range, 30-75 years) with intermediate-risk or high-risk AML in first or second complete remission (CR) were enrolled. hTERT-DCs were generated for 24 patients (73%). A median of 17 intradermal vaccinations (range, 6-32 intradermal vaccinations) containing 1×107 cells were administered as 6 weekly injections followed by 6 biweekly injections. A total of 21 patients (16 in first CR, 3 in second CR, and 2 with early disease recurrence) received hTERT-DCs. RESULTS: hTERT-DCs were well tolerated with no severe toxicities reported, with the exception of 1 patient who developed idiopathic thrombocytopenic purpura. Of the 19 patients receiving hTERT-DCs in CR, 11 patients (58%) developed hTERT-specific T-cell responses that primarily were targeted toward hTERT peptides with predicted low human leukocyte antigen (HLA)-binding affinities. With a median follow-up of 52 months, 58% of patients in CR (11 of 19 patients) were free of disease recurrence at the time of their last follow-up visit; 57% of the patients who were aged ≥60 years (4 of 7 patients) also were found to be free of disease recurrence at a median follow-up of 54 months. CONCLUSIONS: The generation of hTERT-DCs is feasible and vaccination with hTERT-DCs appears to be safe and may be associated with favorable recurrence-free survival. Cancer 2017;123:3061-72. © 2017 American Cancer Society.
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Vacunas contra el Cáncer/uso terapéutico , Células Dendríticas/metabolismo , Inmunoterapia/métodos , Leucaféresis , Leucemia Mieloide Aguda/terapia , Telomerasa/genética , Adulto , Anciano , Supervivencia sin Enfermedad , Ensayo de Immunospot Ligado a Enzimas , Estudios de Factibilidad , Femenino , Humanos , Leucemia Mieloide Aguda/inmunología , Masculino , Persona de Mediana Edad , ARN Mensajero , Inducción de Remisión , Linfocitos T/inmunologíaRESUMEN
Retinal degenerative diseases, including age-related macular degeneration (AMD) and retinitis pigmentosa, lack effective therapies. Conventional monotherapeutic approaches fail to target the multiple affected pathways in retinal degeneration. However, the retinal pigment epithelium (RPE) secretes several neurotrophic factors addressing diverse cellular pathways, potentially preserving photoreceptors. This study explored human embryonic stem cell-derived, polarized RPE soluble factors (PRPE-SF) as a combination treatment for retinal degeneration. PRPE-SF promoted retinal progenitor cell survival, reduced oxidative stress in ARPE-19 cells, and demonstrated critical antioxidant and anti-inflammatory effects for preventing retinal degeneration in the Royal College of Surgeons (RCS) rat model. Importantly, PRPE-SF treatment preserved retinal structure and scotopic b-wave amplitudes, suggesting therapeutic potential for delaying retinal degeneration. PRPE-SF is uniquely produced using biomimetic membranes for RPE polarization and maturation, promoting a protective RPE secretome phenotype. Additionally, PRPE-SF is produced without animal serum to avoid immunogenicity in future clinical development. Lastly, PRPE-SF is a combination of neurotrophic factors, potentially ameliorating multiple dysfunctions in retinal degenerations. In conclusion, PRPE-SF offers a promising therapeutic candidate for retinal degenerative diseases, advancing the development of effective therapeutic strategies for these debilitating conditions.
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Degeneración Retiniana , Epitelio Pigmentado de la Retina , Ratas , Humanos , Animales , Epitelio Pigmentado de la Retina/metabolismo , Degeneración Retiniana/metabolismo , Secretoma , Retina/metabolismo , Células Fotorreceptoras/metabolismoRESUMEN
OBJECTIVE: The primary objective of this study was to evaluate the safety of 3 escalating doses of oligodendrocyte progenitor cells (LCTOPC1; previously known as GRNOPC1 and AST-OPC1) administered at a single time point between 21 and 42 days postinjury to participants with subacute cervical spinal cord injuries (SCIs). The secondary objective was to evaluate changes in neurological function following administration of LCTOPC1. METHODS: This study was designed as an open-label, dose-escalation, multicenter clinical trial. Twenty-five participants with C4-7 American Spinal Injury Association Impairment Scale grade A or B injuries received a single dose of either 2 × 106, 1 × 107, or 2 × 107 LCTOPC1 delivered via intraparenchymal injection into the spinal cord at the site of injury using a custom-designed syringe positioning device. Low-dose tacrolimus was administered until day 60. Outcome measures included adverse event (AE) monitoring and neurological function as measured by the International Standards for Neurological Classification of Spinal Cord Injury. RESULTS: All 25 participants experienced at least one AE, with a total of 534 AEs (32 study-related vs 502 study-unrelated anticipated complications of SCI) reported at the completion of 1-year follow-up. There were 29 serious AEs reported. Two grade 3 serious AEs (CSF leak in one participant and a bacterial infection in another) were considered related to the injection procedure and to immunosuppression with tacrolimus, respectively. The CSF leakage resolved with sequelae, including self-limited altered mental status, and the infection resolved with antibiotic therapy. For all participants, MRI scans demonstrated no evidence of an enlarging mass, spinal cord damage related to the injection procedure, inflammatory lesions in the spinal cord, or masses in the ventricular system. At 1-year follow-up, 21/22 (96%) of the intention-to-treat group recovered one or more levels of neurological function on at least one side of their body, and 7/22 (32%) recovered two or more levels of neurological function on at least one side of their body. CONCLUSIONS: LCTOPC1 can be safely administered to participants in the subacute period after cervical SCI. The injection procedure, low-dose temporary immunosuppression regimen, and LCTOPC1 were well tolerated. The safety and neurological function data support further investigation to determine the efficacy of LCTOPC1 in the treatment of SCI. Clinical trial registration no.: NCT02302157 (ClinicalTrials.gov).
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Médula Cervical , Traumatismos del Cuello , Células Precursoras de Oligodendrocitos , Traumatismos de la Médula Espinal , Humanos , Médula Cervical/lesiones , Tacrolimus/uso terapéuticoRESUMEN
OBJECTIVE: The purpose of this study was to evaluate the safety of oligodendrocyte progenitor cells (LCTOPC1) derived from human pluripotent stem cells administered between 7 and 14 days postinjury to patients with T3 to T11 neurologically complete spinal cord injury (SCI). The rationale for this first-in-human trial was based on evidence that administration of LCTOPC1 supports survival and potential repair of key cellular components and architecture at the SCI site. METHODS: This study was a multisite, open-label, single-arm interventional clinical trial. Participants (n = 5) received a single intraparenchymal injection of 2 × 106 LCTOPC1 caudal to the epicenter of injury using a syringe positioning device. Immunosuppression with tacrolimus was administered for a total of 60 days. Participants were followed with annual in-person examinations and MRI for 5 years at the time of this report and will be followed with annual telephone questionnaires for 6 to 15 years postinjection. The primary endpoint was safety, as measured by the frequency and severity of adverse events related to the LCTOPC1 injection, the injection procedure, and/or the concomitant immunosuppression administered. The secondary endpoint was neurological function as measured by sensory scores and lower-extremity motor scores as measured by the International Standards for Neurological Classification of Spinal Cord Injury examinations. RESULTS: No unanticipated serious adverse events related to LCTOPC1 have been reported with 98% follow-up of participants (49 of 50 annual visits) through the first 10 years of the clinical trial. There was no evidence of neurological decline, enlarging masses, further spinal cord damage, or syrinx formation. MRI results during the long-term follow-up period in patients administered LCTOPC1 cells showed that 80% of patients demonstrated T2 signal changes consistent with the formation of a tissue matrix at the injury site. CONCLUSIONS: This study provides crucial first-in-human safety data supporting the pursuit of future human embryonic stem cell-derived therapies. While we cannot exclude the possibility of future adverse events, the experience in this trial provides evidence that this cell type can be well tolerated by patients, with an event-free period of up to 10 years. Based on the safety profile of LCTOPC1 obtained in this study, a cervical dose escalation trial was initiated (NCT02302157).
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Retinal degeneration, such as age-related macular degeneration (AMD), is a leading cause of blindness worldwide. A myriad of approaches have been undertaken to develop regenerative medicine-based therapies for AMD, including stem cell-based therapies. Rodents as animal models for retinal degeneration are a foundation for translational research, due to the broad spectrum of strains that develop retinal degeneration diseases at different stages. However, mimicking human therapeutic delivery of subretinal implants in rodents is challenging, due to anatomical differences such as lens size and vitreous volume. This surgical protocol aims to provide a guided method for transplanting implants into the subretinal space in rats. A user-friendly comprehensive description of the critical steps has been included. This protocol has been developed as a cost-efficient surgical procedure for reproducibility across different preclinical studies in rats. Proper miniaturization of a human-sized implant is required prior to conducting the surgical experiment, which includes adjustments to the dimensions of the implant. An external approach is used instead of an intravitreal procedure to deliver the implant to the subretinal space. Using a small sharp needle, a scleral incision is performed in the temporal superior quadrant, followed by paracentesis to reduce intraocular pressure, thereby minimizing resistance during the surgical implantation. Next, a balanced salt solution (BSS) injection through the incision is carried out to achieve focal retinal detachment (RD). Lastly, insertion and visualization of the implant into the subretinal space are conducted. Post-operative assessment of the subretinal placement of the implant includes imaging by spectral domain optical coherence tomography (SD-OCT). Imaging follow-ups ascertain the subretinal stability of the implant, before the eyes are harvested and fixated for histological analysis.
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Degeneración Macular , Degeneración Retiniana , Humanos , Ratas , Animales , Degeneración Retiniana/cirugía , Degeneración Retiniana/patología , Reproducibilidad de los Resultados , Modelos Animales de Enfermedad , Degeneración Macular/terapia , Tomografía de Coherencia Óptica/métodosRESUMEN
Dry age-related macular degeneration (AMD) is estimated to impact nearly 300 million individuals globally by 2040. While no treatment options are currently available, multiple clinical trials investigating retinal pigmented epithelial cells derived from human pluripotent stem cells (hPSC-RPE) as a cellular replacement therapeutic are currently underway. It has been estimated that a production capacity of >109 RPE cells annually would be required to treat the afflicted population, but current manufacturing protocols are limited, being labor-intensive and time-consuming. Microcarrier technology has enabled high-density propagation of many adherent mammalian cell types via monolayer culture on surfaces of uM-diameter matrix spheres; however, few studies have explored microcarrier-based culture of RPE cells. Here, we provide an approach to the growth, maturation, and differentiation of hPSC-RPE cells on Cytodex 1 (C1) and Cytodex 3 (C3) microcarriers. We demonstrate that hPSC-RPE cells adhere to microcarriers coated with Matrigel, vitronectin or collagen, and mature in vitro to exhibit characteristic epithelial cell morphology and pigmentation. Microcarrier-grown hPSC-RPE cells (mcRPE) are viable; metabolically active; express RPE signature genes including BEST1, RPE65, TYRP1, and PMEL17; secrete the trophic factors PEDF and VEGF; and demonstrate phagocytosis of photoreceptor outer segments. Furthermore, we show that undifferentiated hESCs also adhere to Matrigel-coated microcarriers and are amenable to directed RPE differentiation. The capacity to support hPSC-RPE cell cultures using microcarriers enables efficient large-scale production of therapeutic RPE cells sufficient to meet the treatment demands of a large AMD patient population.
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Cell-based therapies face challenges, including poor cell survival, immune rejection, and integration into pathologic tissue. We conducted an open-label phase 1/2a clinical trial to assess the safety and preliminary efficacy of a subretinal implant consisting of a polarized monolayer of allogeneic human embryonic stem cell-derived retinal pigmented epithelium (RPE) cells in subjects with geographic atrophy (GA) secondary to dry age-related macular degeneration. Postmortem histology from one subject with very advanced disease shows the presence of donor RPE cells 2 years after implantation by immunoreactivity for RPE65 and donor-specific human leukocyte antigen (HLA) class I molecules. Markers of RPE cell polarity and phagocytosis suggest donor RPE function. Further histologic examination demonstrated CD34+ structures beneath the implant and CD4+, CD68+, and FoxP3+ cells in the tissue. Despite significant donor-host HLA mismatch, no clinical signs of retinitis, vitreitis, vasculitis, choroiditis, or serologic immune response were detected in the deceased subject or any other subject in the study. Subretinally implanted, HLA-mismatched donor RPE cells survive, express functional markers, and do not elicit clinically detectable intraocular inflammation or serologic immune responses even without long-term immunosuppression.
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Atrofia Geográfica , Degeneración Macular , Prótesis e Implantes , Atrofia Geográfica/terapia , Células Madre Embrionarias Humanas/patología , Humanos , Degeneración Macular/patología , Degeneración Macular/terapia , Prótesis e Implantes/efectos adversos , Epitelio Pigmentado de la Retina/patologíaRESUMEN
OBJECTIVE: This study was conducted as a final proof-of-safety direct injection of oligodendrocyte progenitor cells into the uninjured spinal cord prior to translation to the human clinical trials. METHODS: In this study, 107 oligodendrocyte progenitor cells (LCTOPC1, also known as AST-OPC1 and GRNOPC1) in 50-µL suspension were injected directly into the uninjured spinal cords of 8 immunosuppressed Göttingen minipigs using a specially designed stereotactic delivery device. Four additional Göttingen minipigs were given Hanks' Balanced Salt Solution and acted as the control group. RESULTS: Cell survival and no evidence of histological damage, abnormal inflammation, microbiological or immunological abnormalities, tumor formation, or unexpected morbidity or mortality were demonstrated. CONCLUSIONS: These data strongly support the safety of intraparenchymal injection of LCTOPC1 into the spinal cord using a model anatomically similar to that of the human spinal cord. Furthermore, this research provides guidance for future clinical interventions, including mechanisms for precise positioning and anticipated volumes of biological payloads that can be safely delivered directly into uninjured portions of the spinal cord.
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Purpose: To report 1-year follow-up of a phase 1/2a clinical trial testing a composite subretinal implant having polarized human embryonic stem cell (hESC)-derived retinal pigment epithelium (RPE) cells on an ultrathin parylene substrate in subjects with advanced non-neovascular age-related macular degeneration (NNAMD). Methods: The phase 1/2a clinical trial included 16 subjects in two cohorts. The main endpoint was safety assessed at 365 days using ophthalmic and systemic exams. Pseudophakic subjects with geographic atrophy (GA) and severe vision loss were eligible. Low-dose tacrolimus immunosuppression was utilized for 68 days in the peri-implantation period. The implant was delivered to the worst seeing eye with a custom subretinal insertion device in an outpatient setting. A data safety monitoring committee reviewed all results. Results: The treated eyes of all subjects were legally blind with a baseline best-corrected visual acuity (BCVA) of ≤ 20/200. There were no unexpected serious adverse events. Four subjects in cohort 1 had serious ocular adverse events, including retinal hemorrhage, edema, focal retinal detachment, or RPE detachment, which was mitigated in cohort 2 using improved hemostasis during surgery. Although this study was not powered to assess efficacy, treated eyes from four subjects showed an increased BCVA of >5 letters (6-13 letters). A larger proportion of treated eyes experienced a >5-letter gain when compared with the untreated eye (27% vs. 7%; P = not significant) and a larger proportion of nonimplanted eyes demonstrated a >5-letter loss (47% vs. 33%; P = not significant). Conclusions: Outpatient delivery of the implant can be performed routinely. At 1 year, the implant is safe and well tolerated in subjects with advanced dry AMD. Translational Relevance: This work describes the first clinical trial, to our knowledge, of a novel implant for advanced dry AMD.
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Atrofia Geográfica , Trasplante de Células Madre Hematopoyéticas , Degeneración Macular , Estudios de Seguimiento , Atrofia Geográfica/terapia , Humanos , Degeneración Macular/terapia , Agudeza VisualRESUMEN
Age-related macular degeneration (AMD) is the primary cause of blindness in adults over 60 years of age, and clinical trials are currently assessing the therapeutic potential of retinal pigmented epithelial (RPE) cell monolayers on implantable scaffolds to treat this disease. However, challenges related to the culture, long-term storage, and long-distance transport of such implants currently limit the widespread use of adherent RPE cells as therapeutics. Here we report a xeno-free protocol to cryopreserve a confluent monolayer of clinical-grade, human embryonic stem cell-derived RPE cells on a parylene scaffold (REPS) that yields viable, polarized, and functional RPE cells post-thaw. Thawed cells exhibit ≥ 95% viability, have morphology, pigmentation, and gene expression characteristic of mature RPE cells, and secrete the neuroprotective protein, pigment epithelium-derived factor (PEDF). Stability under liquid nitrogen (LN2) storage has been confirmed through one year. REPS were administered immediately post-thaw into the subretinal space of a mammalian model, the Royal College of Surgeons (RCS)/nude rat. Implanted REPS were assessed at 30, 60, and 90 days post-implantation, and thawed cells demonstrate survival as an intact monolayer on the parylene scaffold. Furthermore, immunoreactivity for the maturation marker, RPE65, significantly increased over the post-implantation period in vivo, and cells demonstrated functional attributes similar to non-cryopreserved controls. The capacity to cryopreserve adherent cellular therapeutics permits extended storage and stable transport to surgical sites, enabling broad distribution for the treatment of prevalent diseases such as AMD.
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Criopreservación/métodos , Células Epiteliales/trasplante , Degeneración Macular/terapia , Epitelio Pigmentado de la Retina/trasplante , Manejo de Especímenes/métodos , Trasplante de Células Madre/métodos , Animales , Diferenciación Celular , Línea Celular , Supervivencia Celular , Modelos Animales de Enfermedad , Células Epiteliales/citología , Células Epiteliales/metabolismo , Proteínas del Ojo/metabolismo , Células Madre Embrionarias Humanas/citología , Humanos , Factores de Crecimiento Nervioso/metabolismo , Polímeros , Ratas , Ratas Desnudas , Medicina Regenerativa/métodos , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/metabolismo , Serpinas/metabolismo , Andamios del Tejido , Resultado del Tratamiento , XilenosRESUMEN
Stem cells offer the potential of new therapies for previously untreatable diseases. This session focuses on different aspects of stem cells from embryonic stem cells to adult stem cells and the biology and therapeutic impact of cancer stem cells.
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Trasplante de Células Madre , Células Madre/citología , Células Madre Adultas/citología , Células Madre Adultas/metabolismo , Células Madre Adultas/trasplante , Animales , Células Madre Embrionarias/citología , Células Madre Embrionarias/trasplante , Humanos , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/efectos de los fármacos , Células Madre/metabolismoRESUMEN
PURPOSE: To report the intraoperative methods and anatomic results for subretinal implantation of an investigational human embryonic stem cell-derived retinal pigment epithelium (RPE) monolayer seeded on a synthetic substrate (California Project to Cure Blindness Retinal Pigment Epithelium 1 [CPCB-RPE1]) in geographic atrophy (GA). DESIGN: Single-arm, open label, prospective, nonrandomized, Phase 1/2a study. PARTICIPANTS: Advanced non-neovascular age-related macular degeneration (NNAMD). METHODS: The worse-seeing eye (≤20/200) of each subject underwent subretinal implantation of a single 3.5×6.25 mm CPCB-RPE1 implant with a preplanned primary end point of safety and efficacy at 365 days. Commercially available 23-gauge vitrectomy equipment, custom surgical forceps, and operating microscope with or without intraoperative OCT (iOCT) were used. Exact Wilcoxon rank-sum tests and Spearman rank correlation coefficients were used to assess the association of the percentage of the GA area covered by the implant with patient and surgery characteristics. The partial Spearman correlation coefficient was calculated for the correlation between duration of surgery and baseline GA size after adjustment for surgeon experience. MAIN OUTCOME MEASURES: Intraoperative exploratory measures are reported, including area of GA covered by implant, subretinal position of implant, duration of surgery, and incidence of adverse events. Operative recordings and reports were used to determine exploratory outcome measures. RESULTS: Sixteen subjects were enrolled with a median age of 78 years (range, 69-85 years). Median duration of the surgery for all subjects was 160 minutes (range, 121-466 minutes). Intraoperative OCT was used to guide subretinal placement in 9 cases. Intraoperative OCT was potentially useful in identifying pathology not evident with standard intraoperative visualization. Median GA area at baseline was 13.8 mm2 (range, 6.0-46.4 mm2), and median GA area left uncovered by the implant was 1.7 mm2 (range, 0-20.4 mm2). On average, 86.9% of the baseline GA area was covered by the implant. In 5 subjects, >90% of the GA area was covered. Baseline GA size was inversely correlated with percentage of GA area covered by the implant (rs=-0.72; P = 0.002). No unanticipated serious adverse events related to the implant or surgery were reported. CONCLUSIONS: Surgical implantation of CPCB-RPE1 targeted to the area of GA in subjects with advanced NNAMD is feasible in an outpatient setting. Intraoperative OCT is not necessary but potentially useful in identifying subretinal pathology and confirming implant location.
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Atrofia Geográfica/cirugía , Células Madre Embrionarias Humanas/citología , Epitelio Pigmentado de la Retina/trasplante , Trasplante de Células Madre/métodos , Anciano , Anciano de 80 o más Años , Femenino , Angiografía con Fluoresceína/métodos , Fondo de Ojo , Atrofia Geográfica/patología , Humanos , Masculino , Estudios Prospectivos , Epitelio Pigmentado de la Retina/citología , Tomografía de Coherencia Óptica/métodosRESUMEN
Severe acute liver failure, even when transient, must be treated by transplantation and lifelong immune suppression. Treatment could be improved by bioartificial liver (BAL) support, but this approach is hindered by a shortage of human hepatocytes. To generate an alternative source of cells for BAL support, we differentiated mouse embryonic stem (ES) cells into hepatocytes by coculture with a combination of human liver nonparenchymal cell lines and fibroblast growth factor-2, human activin-A and hepatocyte growth factor. Functional hepatocytes were isolated using albumin promoter-based cell sorting. ES cell-derived hepatocytes expressed liver-specific genes, secreted albumin and metabolized ammonia, lidocaine and diazepam. Treatment of 90% hepatectomized mice with a subcutaneously implanted BAL seeded with ES cell-derived hepatocytes or primary hepatocytes improved liver function and prolonged survival, whereas treatment with a BAL seeded with control cells did not. After functioning in the BAL, ES cell-derived hepatocytes developed characteristics nearly identical to those of primary hepatocytes.
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Diferenciación Celular/fisiología , Trasplante de Células/fisiología , Células Madre Embrionarias/fisiología , Células Madre Embrionarias/trasplante , Hepatocitos/fisiología , Fallo Hepático Agudo/terapia , Hígado Artificial , Activinas/fisiología , Animales , Técnicas de Cultivo de Célula/métodos , Trasplante de Células/métodos , Factor 2 de Crecimiento de Fibroblastos/fisiología , Factor de Crecimiento de Hepatocito/fisiología , Hepatocitos/citología , Humanos , Ratones , Modelos AnimalesRESUMEN
Retinal pigment epithelium (RPE) dysfunction and loss are a hallmark of non-neovascular age-related macular degeneration (NNAMD). Without the RPE, a majority of overlying photoreceptors ultimately degenerate, leading to severe, progressive vision loss. Clinical and histological studies suggest that RPE replacement strategies may delay disease progression or restore vision. A prospective, interventional, U.S. Food and Drug Administration-cleared, phase 1/2a study is being conducted to assess the safety and efficacy of a composite subretinal implant in subjects with advanced NNAMD. The composite implant, termed the California Project to Cure Blindness-Retinal Pigment Epithelium 1 (CPCB-RPE1), consists of a polarized monolayer of human embryonic stem cell-derived RPE (hESC-RPE) on an ultrathin, synthetic parylene substrate designed to mimic Bruch's membrane. We report an interim analysis of the phase 1 cohort consisting of five subjects. Four of five subjects enrolled in the study successfully received the composite implant. In all implanted subjects, optical coherence tomography imaging showed changes consistent with hESC-RPE and host photoreceptor integration. None of the implanted eyes showed progression of vision loss, one eye improved by 17 letters and two eyes demonstrated improved fixation. The concurrent structural and functional findings suggest that CPCB-RPE1 may improve visual function, at least in the short term, in some patients with severe vision loss from advanced NNAMD.
Asunto(s)
Degeneración Macular/terapia , Células Cultivadas , Femenino , Atrofia Geográfica/terapia , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/fisiología , Humanos , Masculino , Estudios Prospectivos , Epitelio Pigmentado de la Retina/citología , Trasplante de Células Madre , Tomografía de Coherencia ÓpticaRESUMEN
A major concern in the use of allotransplantation of human embryonic stem cell (hESC)-based therapies is the possibility of allogeneic rejection by the host's immune system. In this report, we determined the immunological properties of hESC-derived oligodendrocyte progenitor cells (OPC) that have the potential for clinical application for the treatment of patients with spinal cord injury. In vitro immunological studies suggest that hESC-derived OPCs are poor targets for both the innate and the adaptive human immune effector cells as well as resistant to lysis by anti-Neu5Gc antibodies. These results indicate that hESC-derived OPCs retain some of the unique immunological properties of the parental cell line from which they were differentiated.
Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/inmunología , Oligodendroglía/inmunología , Animales , Células Cultivadas , Citocinas/análisis , Proteínas de Unión al ADN/deficiencia , Ensayo de Inmunoadsorción Enzimática/métodos , Feto , Citometría de Flujo/métodos , Humanos , Ratones , Ratones Noqueados , Ratones SCID , Ácidos Siálicos/metabolismo , Médula Espinal/metabolismo , Trasplante de Células Madre/métodos , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunologíaRESUMEN
The utilization of human hepatocytes for biomedical research, drug discovery, and treatment of liver diseases is hindered by the limited availability of donated livers and the variability of their derived hepatocytes. Human embryonic stem cells (hESCs) are pluripotent and provide a unique, unlimited resource for human hepatocytes. However, differentiation of hESCs to hepatocytes remains a challenge. We have developed a multistage procedure by which hESCs can be directly differentiated to hepatocyte-like cells without embryoid body formation and the requirement of sodium butyrate. The hESC-derived hepatocyte-like cells (HLCs) exhibited characteristic hepatocyte morphology, expressed hepatocyte markers, including alpha-fetoprotein, albumin, and hepatocyte nuclear factor 4alpha, and possessed hepatocyte-specific activities, such as p450 metabolism, albumin production, glycogen storage, and uptake and excretion of indocyanine green. Hepatocyte growth factor was found to play a positive role in promoting hepatocyte differentiation. Our differentiation system has shown that hESCs can be differentiated to hepatocyte-like cells capable of executing a range of hepatocyte functions. Therefore, it presents a proof-of-principle of potential applications of using the hESC-derived hepatocytes. Additionally, the hESC-derived HLCs provide a unique model to study the mechanisms involved in human hepatocyte differentiation and liver function.