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2.
BMJ ; 369: m718, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32349978

RESUMO

Head and neck structures govern the vital functions of breathing and swallowing. Additionally, these structures facilitate our sense of self through vocal communication, hearing, facial animation, and physical appearance. Loss of these functions can lead to loss of life or greatly affect quality of life. Regenerative medicine is a rapidly developing field that aims to repair or replace damaged cells, tissues, and organs. Although the field is largely in its nascence, regenerative medicine holds promise for improving on conventional treatments for head and neck disorders or providing therapies where no current standard exists. This review presents milestones in the research of regenerative medicine in head and neck surgery.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Otolaringologia/tendências , Procedimentos Cirúrgicos Reconstrutivos/tendências , Medicina Regenerativa/tendências , Tecidos Suporte , Bioengenharia , Transplante de Células/métodos , Transplante de Células/tendências , Cóclea , Cartilagem da Orelha , Ossos Faciais , Humanos , Laringe , Cartilagens Nasais , Procedimentos Cirúrgicos Reconstrutivos/métodos , Glândulas Salivares , Crânio , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências , Traqueia , Membrana Timpânica
4.
Biochemistry (Mosc) ; 85(Suppl 1): S108-S130, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32087056

RESUMO

It had been commonly believed for a long time, that once established, degeneration of the central nervous system (CNS) is irreparable, and that adult person merely cannot restore dead or injured neurons. The existence of stem cells (SCs) in the mature brain, an organ with minimal regenerative ability, had been ignored for many years. Currently accepted that specific structures of the adult brain contain neural SCs (NSCs) that can self-renew and generate terminally differentiated brain cells, including neurons and glia. However, their contribution to the regulation of brain activity and brain regeneration in natural aging and pathology is still a subject of ongoing studies. Since the 1970s, when Fuad Lechin suggested the existence of repair mechanisms in the brain, new exhilarating data from scientists around the world have expanded our knowledge on the mechanisms implicated in the generation of various cell phenotypes supporting the brain, regulation of brain activity by these newly generated cells, and participation of SCs in brain homeostasis and regeneration. The prospects of the SC research are truthfully infinite and hitherto challenging to forecast. Once researchers resolve the issues regarding SC expansion and maintenance, the implementation of the SC-based platform could help to treat tissues and organs impaired or damaged in many devastating human diseases. Over the past 10 years, the number of studies on SCs has increased exponentially, and we have already become witnesses of crucial discoveries in SC biology. Comprehension of the mechanisms of neurogenesis regulation is essential for the development of new therapeutic approaches for currently incurable neurodegenerative diseases and neuroblastomas. In this review, we present the latest achievements in this fast-moving field and discuss essential aspects of NSC biology, including SC regulation by hormones, neurotransmitters, and transcription factors, along with the achievements of genetic and chemical reprogramming for the safe use of SCs in vitro and in vivo.


Assuntos
Envelhecimento/metabolismo , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/metabolismo , Doenças Neurodegenerativas/terapia , Adulto , Animais , Transplante de Células/efeitos adversos , Transplante de Células/métodos , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Epigênese Genética , Hormônios/metabolismo , Hormônios/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/transplante , Doenças Neurodegenerativas/metabolismo , Neurogênese , Neurotransmissores/metabolismo , Neurotransmissores/farmacologia , Fatores de Transcrição/metabolismo
5.
Nat Rev Neurol ; 16(4): 229-240, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32099190

RESUMO

Spinal cord injury (SCI) remains one of the biggest challenges in the development of neuroregenerative therapeutics. Cell transplantation is one of numerous experimental strategies that have been identified and tested for efficacy at both preclinical and clinical levels in recent years. In this Review, we briefly discuss the state of human olfactory cell transplantation as a therapy, considering both its current clinical status and its limitations. Furthermore, we introduce a mesenchymal stromal cell derived from human olfactory tissue, which has the potential to induce multifaceted reparative effects in the environment within and surrounding the lesion. We argue that no single therapy will be sufficient to treat SCI effectively and that a combination of cell-based, rehabilitation and pharmaceutical interventions is the most promising approach to aid repair. For this reason, we also introduce a novel pharmaceutical strategy based on modifying the activity of heparan sulfate, an important regulator of a wide range of biological cell functions. The multi-target approach that is exemplified by these types of strategies will probably be necessary to optimize SCI treatment.


Assuntos
Heparitina Sulfato/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Mucosa Olfatória/citologia , Traumatismos da Medula Espinal/terapia , Regeneração da Medula Espinal , Transplante de Células/métodos , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Heparina/uso terapêutico , Heparitina Sulfato/análogos & derivados , Humanos , Células-Tronco Mesenquimais/citologia , Regeneração Nervosa , Neuroglia , Mucosa Olfatória/fisiologia , Neurônios Receptores Olfatórios
6.
Proc Natl Acad Sci U S A ; 117(3): 1678-1688, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31915293

RESUMO

Primary human hepatocytes (PHHs) are an essential tool for modeling drug metabolism and liver disease. However, variable plating efficiencies, short lifespan in culture, and resistance to genetic manipulation have limited their use. Here, we show that the pyrrolizidine alkaloid retrorsine improves PHH repopulation of chimeric mice on average 10-fold and rescues the ability of even poorly plateable donor hepatocytes to provide cells for subsequent ex vivo cultures. These mouse-passaged (mp) PHH cultures overcome the marked donor-to-donor variability of cryopreserved PHH and remain functional for months as demonstrated by metabolic assays and infection with hepatitis B virus and Plasmodium falciparum mpPHH can be efficiently genetically modified in culture, mobilized, and then recultured as spheroids or retransplanted to create highly humanized mice that carry a genetically altered hepatocyte graft. Together, these advances provide flexible tools for the study of human liver disease and evaluation of hepatocyte-targeted gene therapy approaches.


Assuntos
Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatopatias/genética , Alcaloides de Pirrolizidina/farmacologia , Animais , Transplante de Células , Quimera , Modelos Animais de Doenças , Feminino , Terapia Genética , Hepatite B , Vírus da Hepatite B , Hepatócitos/transplante , Proteínas de Homeodomínio/genética , Humanos , Hidrolases/genética , Subunidade gama Comum de Receptores de Interleucina/genética , Fígado/patologia , Hepatopatias/patologia , Malária , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Plasmodium falciparum
7.
Vox Sang ; 115(1): 18-26, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31667887

RESUMO

BACKGROUND AND OBJECTIVES: Administration of virus-specific T cells (VSTs) is a viable antiviral treatment strategy after allogeneic HSCT, even if conventional therapies fail. Third-party donors are often chosen for the generation of the VST product. The eligibility of the donor has to be tested in a rigorous donor screening procedure, since the isolation technology only targets pre-existing VSTs. MATERIALS AND METHODS: In a period of 3 years, we performed 32 VST treatments for 28 patients. Targeting four different viruses, 284 healthy individuals underwent 417 donor screening procedures. VSTs were counted by flow cytometry detecting interferon-gamma (IFN-γ) producing T cells. Generation of the VSTs was performed from leukapheresis products in a fully automated and closed system using magnetic cell separation. RESULTS: The mean circulating VST frequencies ranged from 0·006% to 0·328%. The average yield of viable VSTs in the product was 1·83·106 cells, while the average VST dose calculated for the patient's body weight was 4·63·104 /kg. The mean purity - percentage of VSTs within the T cells - of all T-cell products was 62·9%. Correlation was identified between the frequency of the VSTs in the peripheral blood of the donor and the VST numbers of the end product; the strongest correlation was seen for CMV. CONCLUSION: This paper focuses on the T-cell donors, highlighting some key points on the donor selection process. Based on the findings in connection with the CMV therapies, peripheral VST seems to be the best predictor of the VST content of the final product administered to the patient.


Assuntos
Doadores de Sangue , Transplante de Células/métodos , Imunoterapia Adotiva/métodos , Leucaférese , Linfócitos T , Viroses/terapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
EMBO J ; 38(24): e101196, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31750563

RESUMO

Parkinson's disease (PD) is neurodegenerative movement disorder characterized by degeneration of midbrain-type dopamine (mDA) neurons in the substantia nigra (SN). The RNA-binding protein Lin28 plays a role in neuronal stem cell development and neuronal differentiation. In this study, we reveal that Lin28 conditional knockout (cKO) mice show degeneration of mDA neurons in the SN, as well as PD-related behavioral deficits. We identify a loss-of-function variant of LIN28A (R192G substitution) in two early-onset PD patients. Using an isogenic human embryonic stem cell (hESC)/human induced pluripotent stem cell (hiPSC)-based disease model, we find that the Lin28 R192G variant leads to developmental defects and PD-related phenotypes in mDA neuronal cells that can be rescued by expression of wild-type Lin28A. Cell transplantation experiments in PD model rats show that correction of the LIN28A variant in the donor patient (pt)-hiPSCs leads to improved behavioral phenotypes. Our data link LIN28A to PD pathogenesis and suggest future personalized medicine targeting this variant in patients.


Assuntos
Doença de Parkinson/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/fisiologia , Substância Negra/metabolismo , Animais , Comportamento Animal , Transplante de Células , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/fisiologia , Células-Tronco Embrionárias/fisiologia , Edição de Genes , Predisposição Genética para Doença , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Células-Tronco Pluripotentes Induzidas/transplante , Camundongos , Camundongos Knockout , Mutação , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/transplante , Doença de Parkinson/genética , Ratos , Transplante de Células-Tronco
9.
Med Sci (Paris) ; 35(10): 771-778, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31625899

RESUMO

Although the first wave of cell therapy trials has not commonly yielded clinically meaningful improvements, some encouraging hints have emerged which suggest that stem cells or their secreted products could ultimately find a place within the armamentarium of therapies that can be offered to patients with heart failure. In this setting, pluripotent stem cells raise a particular interest because of their unique ability to generate lineage-specific cells which can be transplanted at the desired stage of differentiation. This review discusses the current status of research in this field, the persisting roadblocks that need to be overcome and the approaches which might hasten the clinical applications of this cell type.


Assuntos
Insuficiência Cardíaca/cirurgia , Células-Tronco Pluripotentes/transplante , Transplante de Células/métodos , Ensaios Clínicos como Assunto , Humanos
11.
Biomed Pharmacother ; 118: 109031, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545219

RESUMO

BACKGROUND: This study was conducted to investigate the protective effect of Fms-like tyrosine kinase 3 (FLT3)/FLT3 ligand (FLT3L)-dependent CD103+ dendritic cells (DCs) on hepatic ischemia-reperfusion injury (IRI). METHODS: A mouse model of hepatic IRI and cellular model following hypoxia-reperfusion (H/R) treatment were established. Peripheral blood and liver tissues were obtained and analyzed by flow cytometer in terms of percentage of CD103+DCs and regulatory T (Treg) cells. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were determined to assess liver function. Moreover, pro-inflammatory cytokines levels including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6 were measured using enzyme-linked immunosorbent assay (ELISA). The histological morphology of liver tissues was examined with hematoxylin and eosin (HE) staining. The apoptosis was detected by terminal deoxynucleotidyl transferase (TdT) dUTP Nick End Labeling (TUNEL) assay. Treg-associated cytokines transforming growth factor (TGF)-ß and IL-10 expressions were measured using quantitative real time polymerase chain reaction (qRT-PCR). RESULTS: CD103+ DCs were significantly decreased in peripheral blood and liver tissues of mouse model of hepatic IRI. In vivo experiments indicated that CD103+ DCs infusion ameliorated IRI-induced liver damage and Treg inhibition. Further investigations demonstrated that FLT3/FLT3L-dependent CD103+ DCs suppressed hepatocyte apoptosis via activation of Treg cells in vitro. CONCLUSION: FLT3/FLT3L-induced CD103+ DCs alleviated hepatic IRI through activating Treg cells.


Assuntos
Antígenos CD/metabolismo , Células Dendríticas/transplante , Cadeias alfa de Integrinas/metabolismo , Fígado/irrigação sanguínea , Proteínas de Membrana/metabolismo , Traumatismo por Reperfusão/terapia , Linfócitos T Reguladores/imunologia , Tirosina Quinase 3 Semelhante a fms/metabolismo , Animais , Transplante de Células , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Fígado/imunologia , Testes de Função Hepática , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/imunologia
12.
Ann Transplant ; 24: 532-540, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31527567

RESUMO

BACKGROUND Glenoid labrum injury of the shoulder commonly occurs in athletes, especially those who perform throwing motions. This study investigated the effects of the established allogenic tendon-autologous cartilage cells reconstruction approach in a rabbit model of glenoid labrum damage. MATERIAL AND METHODS The allogenic tendons were isolated and extracted using the chemical extraction method. Cartilage cells were isolated from New Zealand rabbits and identified by detecting type II collagenase. The allogenic tendon-autologous cartilage cells were transplanted to the damaged glenoid labrum. HE staining was used to observe inflammatory cells, Masson staining was used to observe muscle fibers, and scanning electron microscopy (SEM) was used to assess antigenicity of tendon tissues. PSA and AB staining were used to examine neutral protein mucopolysaccharide and acidic protein mucopolysaccharide, respectively. We assessed cartilage cell growth in autologous cartilage cells combined with allogenic tendon transplanted tissues. RESULTS Allogenic tendons were well prepared using chemical extraction method due to use of HE staining, Masson staining, and SEM. TGF-ß1 treatment induced cartilage cell formation and triggered expression of acidic and neutral protein mucopolysaccharides. HE staining, Masson staining, PAS staining, and AB staining methods showed that autologous cartilage cells combined with allogenic tendon transplanted tissues had better growth of cartilage cells. CONCLUSIONS This study establishes the allogenic tendon-autologous cartilage cells reconstruction and transplantation approach and illustrated higher adhesive ability and growth ability, and better chondrogenesis in a rabbit model of glenoid labrum damage.


Assuntos
Cartilagem/transplante , Adesão Celular/fisiologia , Transplante de Células/métodos , Condrogênese/fisiologia , Lesões do Manguito Rotador/cirurgia , Animais , Modelos Animais , Coelhos , Transplante Autólogo
13.
Nat Biotechnol ; 37(10): 1137-1144, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31427818

RESUMO

The utility of autologous induced pluripotent stem cell (iPSC) therapies for tissue regeneration depends on reliable production of immunologically silent functional iPSC derivatives. However, rejection of autologous iPSC-derived cells has been reported, although the mechanism underlying rejection is largely unknown. We hypothesized that de novo mutations in mitochondrial DNA (mtDNA), which has far less reliable repair mechanisms than chromosomal DNA, might produce neoantigens capable of eliciting immune recognition and rejection. Here we present evidence in mice and humans that nonsynonymous mtDNA mutations can arise and become enriched during reprogramming to the iPSC stage, long-term culture and differentiation into target cells. These mtDNA mutations encode neoantigens that provoke an immune response that is highly specific and dependent on the host major histocompatibility complex genotype. Our results reveal that autologous iPSCs and their derivatives are not inherently immunologically inert for autologous transplantation and suggest that iPSC-derived products should be screened for mtDNA mutations.


Assuntos
DNA Mitocondrial/genética , Epitopos/genética , Epitopos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Células-Tronco Pluripotentes Induzidas , Animais , Antígenos , Transplante de Células/métodos , Células-Tronco Embrionárias , Rejeição de Enxerto/imunologia , Humanos , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mutação , Transplante Autólogo
14.
Zhen Ci Yan Jiu ; 44(6): 391-8, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31368260

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with transplantation of Schwann cells (SCs) on limb locomotor, myelin sheath repair and expression of CD4 and CD8 in compressed spinal cord injury (CSCI) rats, so as to explore its mechanisms underlying improvement of CSCI. METHODS: A total of 45 female SD rats were randomly divided into normal control, model, EA, Schwann cell (SC) transplantation, and EA+SC transplantation groups (n=9 rats in each group). The CSCI model was established by laminectomy at T12-L2 and clip compression. Rats of the SC transplantation group accepted injection of the cultured SC suspension (2×106/6 µL) into the central, upper and lower sites of the injured spinal cord (5 mm in depth) 7-8 days after CSCI modeling. EA (2 Hz) was applied to bilateral "Zusanli" (ST36) and "Sanyinjiao" (SP6) for 10 min, once daily and 6 days a week for 3 weeks. The Basso, Beattie and Bresnahan locomotor rating scale (BBB scale) was used to evaluate the function state of CSCI. Morphological changes of the regional injured tissue were observed under light microscope after H.E. staining. The myelin sheath repair state and survival of SCs were detected by Luxol fast blue (LFB) staining and immunofluorescence histochemistry, and the expression of CD4, CD8 and P0 of the injured spinal cord was detected by Western blot. RESULTS: Compared with the normal control group, the BBB scores at the time-points of 0 d, and 1, 2, and 3 weeks were significantly decreased in the model group (P<0.001), and those of the EA+SC transplantation group at the 2nd and 3rd week were significantly higher than those of the model group (P<0.05). No significant changes of BBB scores were found after EA and SC transplantation relevant to the model group (P>0.05). LFB staining showed a disordered arrangement of the nerve fibers in the white matter, myelinociasis and obvious decrease of the medullated fibers in the model group, and these situations were relatively milder in both EA and SC transplantation groups and obviously milder in the EA+SC transplantation group. H.E. staining displayed that the structure of the injured region of the spinal cord was incomplete, accompanied with a large number of defect cavities and neuronal karyopyknosis in the model group, while the structure was relatively clear, with an increase of the normal neurons and fewer neuronal karyopyknosis in the EA+SC transplantation group. Compared with the normal control group, MBP in the model group was significantly decreased (P<0.001),and P0 was significantly increased (P<0.001). Compared with the model group, the expressions of MBP and P0 were significantly increased in the EA, SC transplantation, and EA+SC transplantation groups (P<0.01, P<0.001), and was significantly higher in the EA+SC transplantation group than in both EA and SC transplantation groups (P<0.001). The average immunofluorescence intensity of Hoechst33342-labeled SCs was significantly higher in the EA+SC transplantation group than in the SC transplantation group (P<0.05). After CSCI, the expression levels of spinal CD4, CD8 and P0 proteins had no significant changes in comparison with the normal control group (P>0.05), while after the intervention and in comparison with the model group, the expression levels of P0 protein were significantly increased in the EA, SC transplantation and EA+SC transplantation groups (P<0.05), and was significantly higher in the EA+SC transplantation group than in both EA and SC transplantation groups (P<0.05). The expression levels of CD4 and CD8 proteins were significantly lower in the EA+SC transplantation group than in the SC transplantation group (P<0.05).. CONCLUSION: EA+SCs transplantation can improve the locomotor function in CSCI rats, which may be related to its effects in increasing the survival of transplanted SCs to promote the remyelination and in reducing the immune rejecting reaction.


Assuntos
Eletroacupuntura , Remielinização , Traumatismos da Coluna Vertebral , Animais , Linfócitos T CD8-Positivos , Transplante de Células , Feminino , Ratos , Ratos Sprague-Dawley , Células de Schwann
15.
Am J Ophthalmol ; 208: 242-250, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31449791

RESUMO

PURPOSE: To analyze corneal neovascularization using anterior segment optical coherence tomography angiography (AS-OCTA) in patients following cultivated oral mucosal epithelial sheet transplantation (COMET). DESIGN: Observational case series. METHODS: Nine eyes in 7 patients were analyzed. Four images of corneal quadrant were obtained by AS-OCTA from each patient during follow-up post-COMET in the Department of Ophthalmology at Osaka University Hospital. The depth of corneal neovascularization was evaluated using en face and B-scan images. Each quadrant image was classified as 1 of the following 5 types: stromal, predominantly stromal, epithelial, predominantly epithelial, or avascular. The image quality of slit-lamp photography and AS-OCTA was graded from 0 to 4. Manually segmented images of the epithelial and stromal vessels were obtained. MAIN OUTCOME MEASURES: Depth and image quality of corneal neovascularization following COMET. RESULTS: Six patients were male and 1 was female. The mean patient age was 61.3 ± 19.1 years. Thirty-six quadrant images were obtained, of which 4 (11.1%) were stromal, 16 (44.4%) were predominantly stromal, 3 (8.3%) were epithelial, 11 (30.6%) were predominantly epithelial, and 2 (5.6%) were avascular. The image quality obtained by AS-OCTA was significantly better than that obtained by slit-lamp photography (2.38 ± 0.94 vs 2.03 ± 0.90; P = .021). Segmentation images clearly demonstrated both epithelial and stromal vasculatures individually. CONCLUSIONS: AS-OCTA is useful for evaluation of depth of corneal neovascularization and has the potential to distinguish between conjunctivalization and stromal neovascularization following COMET. Findings on AS-OCTA could contribute to clinical decision making, given that retreatment is required for conjunctivalization after COMET.


Assuntos
Segmento Anterior do Olho/diagnóstico por imagem , Transplante de Células/efeitos adversos , Neovascularização da Córnea/etiologia , Células Epiteliais/transplante , Mucosa Bucal/citologia , Adulto , Idoso , Técnicas de Cultura de Células , Neovascularização da Córnea/diagnóstico por imagem , Feminino , Angiofluoresceinografia , Seguimentos , Humanos , Limbo da Córnea/patologia , Masculino , Pessoa de Meia-Idade , Células-Tronco/patologia , Tomografia de Coerência Óptica
16.
Ann Transplant ; 24: 472-480, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31406101

RESUMO

BACKGROUND Hepatocyte transplantation (HCTx) has the potential for the treatment of end-stage liver disease. However, failure of engraftment and the long-term acceptance of cellular allografts remain significant challenges for its clinical application. The aim of this study was to investigate the efficacy of the immunosuppressive agents, Cyclosporine, Everolimus, and Belatacept to suppress the alloresponse of primary human hepatocytes in a mixed lymphocyte-hepatocyte culture (MLHC) and their potential hepatotoxicity in vitro. MATERIAL AND METHODS Primary human hepatocytes were co-cultured with allogeneic peripheral blood mononuclear cells (PBMCs) in an MLHC. Proliferative alloresponses were determined by flow cytometry, and cytokine secretion was measured using Luminex-based multiplex technology. Using an MLHC, the alloresponses of primary human hepatocytes were compared in the presence and absence of Cyclosporine, Everolimus, and Belatacept. Cultured primary human hepatocytes were assessed for the production of albumin, urea, aspartate transaminase (AST) and DNA content. Metabolic activity was determined with the MTT assay. RESULTS Immune responses induced by primary human hepatocytes were effectively suppressed by Cyclosporine, Everolimus, and Belatacept. Everolimus significantly reduced the metabolic activity of primary human hepatocytes in vitro, suggesting impairment of cell viability. However, further functional analysis showed no significant differences between treated and untreated controls. CONCLUSIONS Cyclosporine, Everolimus, and Belatacept suppressed the alloresponse of primary human hepatocytes in an MLHC without significant cytotoxicity or functional cell impairment.


Assuntos
Transplante de Células/métodos , Hepatócitos/efeitos dos fármacos , Hepatócitos/transplante , Imunossupressores/farmacologia , Linfócitos/efeitos dos fármacos , Abatacepte/farmacologia , Técnicas de Cocultura , Ciclosporina/farmacologia , Doença Hepática Terminal/terapia , Everolimo/farmacologia , Hepatócitos/citologia , Humanos , Linfócitos/citologia
17.
Transpl Immunol ; 56: 101225, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31330261

RESUMO

Myeloid-derived suppressor cells (MDSC) are a heterogenous population of immunosuppressive myeloid cells now considered important immune regulatory cells in diverse clinical conditions, including cancer, chronic inflammatory disorders and transplantation. In rodents, MDSC administration can inhibit graft-versus-host disease lethality and enhance organ or pancreatic islet allograft survival. There is also evidence, however, that under systemic inflammatory conditions, adoptively-transferred MDSC can rapidly lose their suppressive function. To our knowledge, there are no reports of autologous MDSC administration to either human or clinically-relevant non-human primate (NHP) transplant recipients. Monocytic (m) MDSC have been shown to be more potent suppressors of T cell responses than other subsets of MDSC. Following their characterization in rhesus macaques, we have conducted a preliminary analysis of the feasibility and preliminary efficacy of purified mMDSC infusion into MHC-mismatched rhesus kidney allograft recipients. The graft recipients were treated with rapamycin and the high affinity variant of the T cell co-stimulation blocking agent cytotoxic T lymphocyte antigen 4 Ig (Belatacept) that targets the B7-CD28 pathway. Graft survival and histology were not affected by infusions of autologous, leukapheresis product-derived mMDSC on days 7 and 14 post-transplant (cumulative totals of 3.19 and 1.98 × 106 cells/kg in n = 2 recipients) compared with control monkeys that did not receive MDSC (n = 2). Sequential analyses of effector T cell populations revealed no differences between the groups. While these initial findings do not provide evidence of efficacy under the conditions adopted, further studies in NHP, designed to ascertain the appropriate mMDSC source and dose, timing and anti-inflammatory/immunosuppressive agent support are likely to prove instructive regarding the therapeutic potential of MDSC in organ transplantation.


Assuntos
Transplante de Células/métodos , Rejeição de Enxerto/prevenção & controle , Transplante de Rim , Células Supressoras Mieloides/transplante , Linfócitos T/imunologia , Abatacepte/uso terapêutico , Animais , Células Cultivadas , Modelos Animais de Doenças , Estudos de Viabilidade , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade/imunologia , Humanos , Tolerância Imunológica , Imunossupressores/uso terapêutico , Macaca mulatta , Sirolimo/uso terapêutico , Transplante Autólogo , Transplante Homólogo
18.
Curr Opin Organ Transplant ; 24(5): 555-561, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31356234

RESUMO

PURPOSE OF REVIEW: To discuss existing expectations from organoids and how they can affect biomedical research and society, and to analyse the current limitations and how they can potentially be overcome. RECENT FINDINGS: Recent success with engineering human organoids has created great enthusiasm and expectations, especially for their potential as tissue substitutes. The most feasible applications for organoid technologies at the moment are: drug testing, disease modelling and studying of human development. SUMMARY: Being able to engineer transplantable tissues in a dish would fundamentally change the way we conduct biomedical research and clinical practice, and impact important aspects of science and society - from animal experimentation to personalized medicine, bioethics, transplantation and gene therapy. However, whether organoids will soon be able to fulfil these expectations is still unclear, because of significant existing limitations. By answering a set of questions, here I will examine the expectations on the future of organoids and how they can affect the field and the society, I will analyse the most important limitations that still prevent the production of transplantable human tissues in a dish, and discuss possible solution strategies.


Assuntos
Transplante de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Organoides/citologia , Animais , Pesquisa Biomédica , Humanos , Medicina de Precisão , Engenharia Tecidual
19.
Invest Ophthalmol Vis Sci ; 60(7): 2438-2448, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31158276

RESUMO

Purpose: Corneal endothelial dysfunction leads to corneal edema, pain, and vision loss. Adequate animal models are needed to study the safety and efficacy of novel cell therapies as an alternative to corneal transplantation. Methods: Primary human corneal endothelial cells (HCECs) were isolated from cadaveric donor corneas, expanded in vitro, transduced to express green fluorescent protein (GFP), loaded with superparamagnetic nanoparticles, and injected into the anterior chamber of adult rabbits immediately after endothelial cell or Descemet's membrane stripping. The same volume of balanced salt solution plus (BSS+) was injected in control eyes. We compared different models for inducing corneal edema in rabbits, and examined the ability of transplanted HCECs to reduce corneal edema over time by measuring central corneal thickness and tracking corneal clarity. GFP-positive donor cells were tracked in vivo using optical coherence tomography (OCT) fluorescence angiography module, and the transplanted cells were confirmed by human nuclei immunostaining. Results: Magnetic HCECs integrated onto the recipient corneas with intact Descemet's membrane, and donor identity was confirmed by GFP expression and immunostaining for human nuclei marker. Donor HCECs formed a monolayer on the posterior corneal surface and expressed HCEC functional markers of tight junction formation. No GFP-positive cells were observed in the trabecular meshwork or on the iris, and intraocular pressure remained stable through the length of the study. Conclusions: Our results demonstrate magnetic cell-based therapy efficiently delivers HCECs to restore corneal transparency without detectable toxicity or adverse effect on intraocular pressure. Magnetic delivery of HCECs may enhance corneal function and should be explored further for human therapies.


Assuntos
Transplante de Células/métodos , Doenças da Córnea/cirurgia , Sistemas de Liberação de Medicamentos , Epitélio Posterior/transplante , Terapia de Campo Magnético/métodos , Nanopartículas de Magnetita/química , Animais , Câmara Anterior/citologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Doenças da Córnea/patologia , Portadores de Fármacos , Epitélio Posterior/metabolismo , Epitélio Posterior/cirurgia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Pressão Intraocular , Substâncias Luminescentes/metabolismo , Modelos Animais , Coelhos , Doadores de Tecidos , Transfecção
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