RESUMEN
In biomedical research, biorepositories are pivotal resources that safeguard and supply clinical samples for scientific investigators. Proper long-term cryopreservation conditions are essential to maintain biospecimen quality. In this study, we analyzed the efficacy of sample cryopreservation at the Texas Heart Institute Biorepository and Biospecimen Profiling Core (THI-BRC). Our assessments included a thorough review of internal processes, quality reports, and both internal and external audit outcomes. We examined the integrity of human bone marrow-derived multipotent mesenchymal stromal cells (BM-MSCs) that were cryopreserved for over 5 years. These samples originated from randomly selected clinical trial participants or commercially sourced cell lines. Parameters such as cell viability, DNA and RNA integrity, population doubling time, sterility, and BM-MSC-specific attributes such as surface antigen expression and differentiation potential were studied. BM-MSC samples cryopreserved for â¼6 months served as our control. Our results demonstrated that the 5-year cryopreserved samples maintained their integrity compared with the shorter-term stored control samples. Moreover, THI-BRC has met accreditation agency standards and has not received any repeated deficiencies over 7 years. Collectively, our findings affirm that THI-BRC's biospecimen storage protocols align with accepted standards as confirmed by the quality assessment of long-term stored clinical samples.
RESUMEN
Understanding the hazards of space radiation is imperative as astronauts begin voyaging on missions with increasing distances from Earth's protective shield. Previous studies investigating the acute or long-term effects of specific ions comprising space radiation have revealed threats to organs generally considered radioresistant, like the brain, and have shown males to be more vulnerable than their female counterparts. However, astronauts will be exposed to a combination of ions that may result in additive effects differing from those of any one particle species. To better understand this nuance, we irradiated 4-month-old male and female, wild-type and Alzheimer's-like mice with 0, 0.5, or 0.75 Gy galactic cosmic ray simulation (GCRsim) or 0, 0.75, or 2 Gy gamma radiation (wild-type only). At 11 months, mice underwent brain and heart MRIs or behavioral tests, after which they were euthanized to assess amyloid-beta pathology, heart and kidney gene expression and fibrosis, and plasma cytokines. Although there were no changes in amyloid-beta pathology, we observed many differences in brain MRIs and behavior, including opposite effects of GCRsim on motor coordination in male and female transgenic mice. Additionally, several genes demonstrated persistent changes in the heart and kidney. Overall, we found sex- and genotype-specific, long-term effects of GCRsim and gamma radiation on the brain, heart, and kidney.
Asunto(s)
Enfermedad de Alzheimer , Encéfalo , Radiación Cósmica , Rayos gamma , Corazón , Riñón , Ratones Transgénicos , Animales , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/patología , Femenino , Masculino , Rayos gamma/efectos adversos , Encéfalo/efectos de la radiación , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Ratones , Riñón/efectos de la radiación , Riñón/metabolismo , Riñón/patología , Corazón/efectos de la radiación , Radiación Cósmica/efectos adversos , Mutación , Caracteres Sexuales , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/genética , Modelos Animales de Enfermedad , Factores SexualesRESUMEN
Ischemic heart disease, a leading cause of death worldwide, manifests clinically as myocardial infarction. Contemporary therapies using mesenchymal stromal cells (MSCs) and their derivative (exosomes, EXOs) were developed to decrease the progression of cell damage during ischemic injury. Laminin alpha 2 (LAMA2) is an important extracellular matrix protein of the heart. Here, we generated MSC-derived exosomes cultivated under LAMA2 coating to enhance human-induced pluripotent stem cell (hiPSC)-cardiomyocyte recognition of LAMA2-EXOs, thus, increasing cell protection during ischemia reoxygenation. We mapped the mRNA content of LAMA2 and gelatin-EXOs and identified 798 genes that were differentially expressed, including genes associated with cardiac muscle development and extracellular matrix organization. Cells were treated with LAMA2-EXOs 2 h before a 4 h ischemia period (1% O2, 5% CO2, glucose-free media). LAMA2-EXOs had a two-fold protective effect compared to non-treatment on plasma membrane integrity and the apoptosis activation pathway; after a 1.5 h recovery period (20% O2, 5% CO2, cardiomyocyte-enriched media), cardiomyocytes treated with LAMA2-EXOs showed faster recovery than did the control group. Although EXOs had a protective effect on endothelial cells, there was no LAMA2-enhanced protection on these cells. This is the first report of LAMA2-EXOs used to treat cardiomyocytes that underwent ischemia-reoxygenation injury. Overall, we showed that membrane-specific EXOs may help improve cardiomyocyte survival in treating ischemic cardiovascular disease.
Asunto(s)
Exosomas , Células Madre Pluripotentes Inducidas , Laminina , Humanos , Miocitos Cardíacos , Dióxido de Carbono , Células Endoteliales , IsquemiaRESUMEN
This study investigated cardiac stress and mitochondrial oxidative phosphorylation (OxPhos) in human donation after circulatory death (DCD) hearts regarding warm ischemic time (WIT) and subsequent cold storage and compared them with that of human brain death donor (DBD) hearts. A total of 24 human hearts were procured for the research study-6 in the DBD group and 18 in the DCD group. DCD group was divided into three groups (n = 6) based on different WITs (20, 40, and 60 min). All hearts received del Nido cardioplegia before being placed in normal saline cold storage for 6 h. Left ventricular biopsies were performed at hours 0, 2, 4, and 6. Cardiac stress [nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits: 47-kDa protein of phagocyte oxidase (p47phox), 91-kDa glycoprotein of phagocyte oxidase (gp91phox)] and mitochondrial oxidative phosphorylation [OxPhos, complex I (NADH dehydrogenase) subunit of ETC (CI)-complex V (ATP synthase) subunit of ETC (CV)] proteins were measured in cardiac tissue and mitochondria respectively. Modulation of cardiac stress and mitochondrial dysfunction were observed in both DCD and DBD hearts. However, DCD hearts suffered more cardiac stress (overexpressed NADPH oxidase subunits) and diminished mitochondrial OxPhos than DBD hearts. The severity of cardiac stress and impaired oxidative phosphorylation in DCD hearts correlated with the longer WIT and subsequent cold storage time. More drastic changes were evident in DCD hearts with a WIT of 60 min or more. Activation of NADPH oxidase via overproduction of p47phox and gp91phox proteins in cardiac tissue may be responsible for cardiac stress leading to diminished mitochondrial oxidative phosphorylation. These protein changes can be used as biomarkers for myocardium damage and might help assess DCD and DBD heart transplant suitability.NEW & NOTEWORTHY First human DCD heart research studied cardiac stress and mitochondrial dysfunction concerning WIT and the efficacy of del Nido cardioplegia as an organ procurement solution and subsequent cold storage. Mild to moderate cardiac stress and mitochondrial dysfunction were noticed in DCD hearts with WIT 20 and 40 min and cold storage for 4 and 2 h, respectively. These changes can serve as biomarkers, allowing interventions to preserve mitochondria and extend WIT in DCD hearts.
Asunto(s)
Trasplante de Corazón , Enfermedades Mitocondriales , Humanos , Muerte Encefálica , Fosforilación Oxidativa , Donantes de Tejidos , NADPH Oxidasas , Biomarcadores , Oxidorreductasas , Muerte , Estudios RetrospectivosRESUMEN
BACKGROUND: Single-dose del Nido solution was recently used in human donation after circulatory death (DCD) heart procurement. We compared the effect of del Nido cardioplegia on myocardial edema, inflammatory response, and injury in human DCD hearts and human donation after brain death (DBD) hearts with different warm ischemic times (WIT) and subsequent cold saline storage times (CST). METHODS: A total of 24 human hearts, including 6 in the DBD group and 18 in the DCD group-were procured for the research study. The DCD group was divided into 3 subgroups based on WIT: 20, 40, and ≥60 minutes. All hearts received 1 L of del Nido cardioplegia before being placed in cold saline for 6 hours. Left ventricular biopsies were performed at 0, 2, 4, and 6 hours. Temporal changes in myocardial edema, inflammatory cytokines (TNF-α, IL-6, and IL-1ß), and histopathology injury scores were compared between the DBD and DCD groups. RESULTS: DCD hearts showed more profound changes in myocardial edema, inflammation, and injury than DBD hearts at baseline and subsequent CST. The DCD heart with WIT of 20 and 40 minutes with CST of 4 and 2 hours, respectively, appeared to have limited myocardial edema, inflammation, and injury. DCD hearts with WIT ≥60 minutes showed severe myocardial edema, inflammation, and injury at baseline and subsequent CST. CONCLUSIONS: Single-dose cold del Nido cardioplegia and subsequent cold normal saline storage can preserve both DCD and DBD hearts. DCD hearts have been shown to be able to tolerate a WIT of 20 minutes and subsequent CST of 4 hours without experiencing significant myocardial edema, inflammation, and injury.
Asunto(s)
Trasplante de Corazón , Isquemia Tibia , Humanos , Trasplante de Corazón/efectos adversos , Corazón/fisiología , Edema/etiología , Inflamación , Donantes de TejidosRESUMEN
Cardiovascular disease is the leading cause of death and disability worldwide. Early detection and treatment of cardiovascular disease are crucial for patient survival and long-term health. Despite advances in cardiovascular disease biomarkers, the prevalence of cardiovascular disease continues to increase worldwide as the global population ages. To address this problem, novel biomarkers that are more sensitive and specific to cardiovascular diseases must be developed and incorporated into clinical practice. Exosomes are promising biomarkers for cardiovascular disease. These small vesicles are produced and released into body fluids by all cells and carry specific information that can be correlated with disease progression. This article reviews the advantages and limitations of existing biomarkers for cardiovascular disease, such as cardiac troponin and cytokines, and discusses recent evidence suggesting the promise of exosomes as cardiovascular disease biomarkers.
Asunto(s)
Enfermedades Cardiovasculares , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , BiomarcadoresRESUMEN
Lung allograft recipients have worse survival than all other solid organ transplant recipients, largely because of primary graft dysfunction (PGD), a major form of acute lung injury affecting a third of lung recipients within the first 72 h after transplant. PGD is the clinical manifestation of ischemia-reperfusion injury and represents the predominate cause of early morbidity and mortality. Despite PGD's impact on lung transplant outcomes, no targeted therapies are currently available; hence, care remains supportive and largely ineffective. This review focuses on molecular and innate immune mechanisms of ischemia-reperfusion injury leading to PGD. We also discuss novel research aimed at discovering biomarkers that could better predict PGD and potential targeted interventions that may improve outcomes in lung transplantation.
Asunto(s)
Trasplante de Pulmón , Disfunción Primaria del Injerto , Daño por Reperfusión , Humanos , Disfunción Primaria del Injerto/etiología , Factores de Riesgo , Trasplante de Pulmón/efectos adversos , PulmónRESUMEN
During fetal development, cardiomyocytes switch from glycolysis to oxidative metabolism to sustain the energy requirements of functional cells. State-of-the-art cardiac differentiation protocols yield phenotypically immature cardiomyocytes, and common methods to improve metabolic maturation require multistep protocols to induce maturation only after cardiac specification is completed. Here, we describe a maturation method using ventricle-derived decellularized extracellular matrix (dECM) that promoted early-stage metabolic maturation of cardiomyocytes differentiated from human induced pluripotent stem cells (hiPSCs). Chemically and architecturally preserved particles (45-500 µm) of pig ventricular dECM were added to hiPSCs at the start of differentiation. At the end of our maturation protocol (day 15 of cardiac differentiation), we observed an intimate interaction between cardiomyocytes and dECM particles without impairment of cardiac differentiation efficiency (approx. 70% of cTNT+). Compared with control cells (those cultured without pig dECM), 15-day-old dECM-treated cardiomyocytes demonstrated increased expression of markers related to cardiac metabolic maturation, MAPK1, FOXO1, and FOXO3, and a switch from ITGA6 (the immature integrin isoform) to ITGA3 and ITGA7 (those present in adult cardiomyocytes). Electrical parameters and responsiveness to dobutamine also improved in pig ventricular dECM-treated cells. Extending the culture time to 30 days, we observed a switch from glucose to fatty acid metabolism, indicated by decreased glucose uptake and increased fatty acid consumption in cells cultured with dECM. Together, these data suggest that dECM contains endogenous cues that enable metabolic maturation of hiPSC-CMs at early stages of cardiac differentiation.
Asunto(s)
Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Adulto , Humanos , Animales , Porcinos , Matriz Extracelular Descelularizada , Polvos/metabolismo , Diferenciación Celular , Ácidos Grasos/metabolismo , Matriz Extracelular/metabolismoRESUMEN
BACKGROUND: Processes that activate the immune system during lung transplantation can lead to primary graft dysfunction (PGD) or allograft rejection. METHODS: We analyzed cytokine expression profiles after reperfusion and allograft outcomes in a cohort of patients (n = 59) who underwent lung transplantation off-pump (n = 26), with cardiopulmonary bypass (CPB; n = 18), or with extracorporeal membrane oxygenation (ECMO; n = 15). Peripheral blood was collected from patients at baseline and at 6 and 72 h after reperfusion. To adjust for clinical differences between groups, we utilized a linear mixed model with overlap weighting. RESULTS: PGD3 was present at 48 or 72 h after reperfusion in 7.7% (2/26) of off-pump cases, 20.0% (3/15) of ECMO cases, and 38.9% (7/18) of CPB cases (p = 0.04). The ECMO and CPB groups had greater reperfusion-induced increases in MIP-1B, IL-6, IL-8, IL-9, IL1-ra, TNF-alpha, RANTES, eotaxin, IP-10, and MCP-1 levels than the off-pump group. Cytokine expression profiles after reperfusion were not significantly different between ECMO and CPB groups. CONCLUSION: Our data suggest that, compared with an off-pump approach, the intraoperative use of ECMO or CPB during lung transplantation is associated with greater reperfusion-induced cytokine release and graft injury.
Asunto(s)
Trasplante de Pulmón , Humanos , Resultado del Tratamiento , Reperfusión , Trasplante Homólogo , Trasplante de Pulmón/efectos adversos , Puente Cardiopulmonar/efectos adversos , Estudios Retrospectivos , BiomarcadoresRESUMEN
Objetivo: Comprender el significado que atribuyen los padres y madres a la experiencia de estar junto a su hijo hospitalizado en una unidad de oncología de un hospital público de Chile. Metodología: Paradigma de investigación interpretativo, enfoque fenomenológico hermenéutico de Van Manen. Se realizó una entrevista en profundidad a 10 participantes y las narrativas se analizaron mediante un análisis temático con enfoque selectivo de lectura. El artículo fue aprobado por el comité de ética de la Pontificia Universidad Católica de Chile. Resultados: La experiencia de hospitalización significó "cambiar la vida de un día para otro"; este resultado se conformó por dos estructuras: 1) "Cuando te dan el diagnóstico se te derrumba el mundo", que contiene momentos difíciles como la hospitalización en que reciben el diagnóstico, los momentos en que el hijo/a sufre, las situaciones de riesgo vital, el cansancio de las madres y padres y los cambios que afectan a la familia, y 2) "Recibir una luz de ayuda durante la hospitalización", que describe la importancia de un espacio físico tranquilo, de un equipo de salud con un trato cariñoso y de compartir experiencias con otras madres y padres. Conclusiones: La hospitalización representa una transformación en el mundo vida de los padres y madres, es vital que el equipo de salud atienda las necesidades físicas y emocionales que derivan de este cambio en el espacio y relaciones que estos vivencian.
Objetivo: Entender o significado atribuído pelos pais à experiência de estar com seu filho hospitalizado em uma unidade oncológica de um hospital público no Chile. Metodologia: Paradigma de pesquisa interpretativa, abordagem fenomenológica hermenêutica de Van Manen. Foi realizada uma entrevista aprofundada com 10 participantes e as narrativas foram analisadas utilizando uma análise temática com uma abordagem de leitura seletiva. O artigo foi aprovado pelo comitê de ética da Pontificia Universidad Católica de Chile. Resultados: A experiência da hospitalização significou "Muda a vida de um dia para o outro"; este resultado foi moldado por duas estruturas: 1) "Quando você recebe o diagnóstico, seu mundo desmorona", que contém momentos difíceis como a hospitalização quando recebem o diagnóstico, momentos em que a criança sofre, situações de risco de vida, cansaço das mães e dos pais e mudanças que afetam a família, e 2) "Receber uma luz de ajuda durante a hospitalização", que descreve a importância de um espaço físico tranquilo, uma equipe de saúde com um tratamento cuidadoso e compartilhando experiências com outras mães e pais. Conclusões: A hospitalização representa uma transformação no mundo da vida dos pais, é vital que a equipe de saúde atenda às necessidades físicas e emocionais que surgem desta mudança no espaço e nos relacionamentos que eles experimentam.
Objective: To understand the meaning attributed by parents to the experience of being with their hospitalized child in an oncology unit of a public hospital in Chile. . Methodology: Interpretative research paradigm, Van Manen's hermeneutic phenomenological approach. In-depth interviews were conducted with 10 participants and the narratives were analyzed by means of a thematic analysis with selective reading approach. The article was approved by the ethics committee of the Pontificia Universidad Católica de Chile. Results: The experience of hospitalization meant "It turns life upside down"; this outcome was shaped by two structures: 1) "When they give you the diagnosis your world falls apart", which contains difficult moments such as the hospitalization when they receive the diagnosis, the moments when the child suffers, life-threatening situations, the tiredness of mothers and fathers and the changes that affect the family, and 2) "Receiving a helping light during hospitalization", which describes the importance of a quiet physical space, a health team with a caring treatment and sharing experiences with other parents. Conclusions: Hospitalization represents a transformation in the life world of parents, it is vital that the health team attends to the physical and emotional needs that derive from this change in the space and relationships they experience.
RESUMEN
Laminins (LNs) play a central role in the self-assembly and maintenance of basement membranes and are involved in critical interactions between cells and other extracellular matrix (ECM) proteins. Among the defined, xeno-free ECM culture matrices, LNs-namely LN521-have emerged as promising coating systems for the large-scale expansion of induced pluripotent stem cells (iPSCs). The biologic activity of LNs is enhanced by their acidification-induced self-polymerization into a cell-associated network called polylaminin (polyLN), which can recapitulate the native-like polymeric array in a cell-free system. Here, we show for the first time to our knowledge that polyLN521 displays a native-like hexagonal-like structure and that, at basal and low concentrations, it permits the large-scale expansion of human iPSCs. Human iPSCs expanded with polyLN521 maintained the pluripotent state and showed no impairment of karyotype stability or telomere length. These results suggest that low-concentration polyLN521 is a stable and cost-effective coating for large-scale iPSC expansion.
Asunto(s)
Células Madre Pluripotentes Inducidas , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Laminina/farmacología , Laminina/metabolismo , Polimerizacion , Matriz ExtracelularRESUMEN
The clinical use of circulating biomarkers for primary graft dysfunction (PGD) after lung transplantation has been limited. In a prospective single-center cohort, we examined the use of plasma protein biomarkers as indicators of PGD severity and duration after lung transplantation. The study comprised 40 consecutive lung transplant patients who consented to blood sample collection immediately pretransplant and at 6, 24, 48, and 72 h after lung transplant. An expert grader determined the severity and duration of PGD and scored PGD at T0 (6 h after reperfusion), T24, T48, and T72 h post-reperfusion using the 2016 ISHLT consensus guidelines. A bead-based multiplex assay was used to measure 27 plasma proteins including cytokines, growth factors, and chemokines. Enzyme-linked immunoassay was used to measure cell injury markers including M30, M65, soluble receptor of advanced glycation end-products (sRAGE), and plasminogen activator inhibitor-1 (PAI-1). A pairwise comparisons analysis was used to assess differences in protein levels between PGD severity scores (1, 2, and 3) at T0, T24, T48, and T72 h. Sensitivity and temporal analyses were used to explore the association of protein expression patterns and PGD3 at T48-72 h (the most severe, persistent form of PGD). We used the Benjamini-Hochberg method to adjust for multiple testing. Of the 40 patients, 22 (55%) had PGD3 at some point post-transplant from T0 to T72 h; 12 (30%) had PGD3 at T48-72 h. In the pairwise comparison, we identified a robust plasma protein expression signature for PGD severity. In the sensitivity analysis, using a linear model for microarray data, we found that differential perioperative expression of IP-10, MIP1B, RANTES, IL-8, IL-1Ra, G-CSF, and PDGF-BB correlated with PGD3 development at T48-72 h (FDR < 0.1 and p < 0.05). In the temporal analysis, using linear mixed modeling with overlap weighting, we identified unique protein patterns in patients who did or did not develop PGD3 at T48-72 h. Our findings suggest that unique inflammatory protein expression patterns may be informative of PGD severity and duration. PGD biomarker panels may improve early detection of PGD, predict its clinical course, and help monitor treatment efficacy in the current era of lung transplantation.
Asunto(s)
Trasplante de Pulmón , Disfunción Primaria del Injerto , Becaplermina , Biomarcadores , Quimiocina CCL5 , Quimiocina CXCL10 , Estudios de Cohortes , Factor Estimulante de Colonias de Granulocitos , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-8 , Trasplante de Pulmón/efectos adversos , Inhibidor 1 de Activador Plasminogénico , Disfunción Primaria del Injerto/diagnóstico , Disfunción Primaria del Injerto/etiología , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
Close examination of the initial results of cardiovascular cell therapy clinical trials indicates the importance of patient-specific differences on outcomes and the need to optimize or customize cell therapies. The fields of regenerative medicine and cell therapy have transitioned from using heterogeneous bone marrow mononuclear cells (BMMNCs) to mesenchymal stromal cells (MSCs), which are believed to elicit benefits through paracrine activity. Here, we examined MSCs from the BMMNCs of heart failure patients enrolled in the FOCUS-CCTRN trial. We sought to identify differences in MSCs between patients who improved and those who declined in heart function, regardless of treatment received. Although we did not observe differences in the cell profile of MSCs between groups, we did find significant differences in the MSC secretome profile between patients who improved or declined. We conclude that "mining" the MSC secretome may provide clues to better understand the impact of patient characteristics on outcomes after cell therapy and this knowledge can inform future cell therapy trials.
Asunto(s)
Células Madre Mesenquimatosas , Disfunción Ventricular Izquierda , Tratamiento Basado en Trasplante de Células y Tejidos , Humanos , Medicina Regenerativa/métodos , SecretomaRESUMEN
There are few existing methods for shortening the decellularization period for a human-sized whole-liver scaffold. Here, we describe a protocol that enables effective decellularization of the liver obtained from pigs weigh 120 ± 4.2 kg within 72 h. Porcine livers (approx. 1.5 kg) were decellularized for 3 days using a combination of chemical and enzymatic decellularization agents. After trypsin, sodium deoxycholate, and Triton X-100 perfusion, the porcine livers were completely translucent. Our protocol was efficient to promote cell removal, the preservation of extracellular matrix (ECM) components, and vascular tree integrity. In conclusion, our protocol is efficient to promote human-sized whole-liver scaffold decellularization and thus useful to generate bioengineered livers to overcome the shortage of organs.
Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Animales , Matriz Extracelular , Humanos , Hígado , Perfusión , Porcinos , Ingeniería de Tejidos/métodosRESUMEN
Bioengineering a solid organ for organ replacement is a growing endeavor in regenerative medicine. Our approach - recellularization of a decellularized cadaveric organ scaffold with human cells - is currently the most promising approach to building a complex solid vascularized organ to be utilized in vivo, which remains the major unmet need and a key challenge. The 2008 publication of perfusion-based decellularization and partial recellularization of a rat heart revolutionized the tissue engineering field by showing that it was feasible to rebuild an organ using a decellularized extracellular matrix scaffold. Toward the goal of clinical translation of bioengineered tissues and organs, there is increasing recognition of the underlying need to better integrate basic science domains and industry. From the perspective of a research group focusing on whole heart engineering, we discuss the current approaches and advances in whole organ engineering research as they relate to this multidisciplinary field's 3 major pillars: organ scaffolds, large numbers of cells, and biomimetic bioreactor systems. The success of whole organ engineering will require optimization of protocols to produce biologically-active scaffolds for multiple organ systems, and further technological innovation both to produce the massive quantities of high-quality cells needed for recellularization and to engineer a bioreactor with physiologic stimuli to recapitulate organ function. Also discussed are the challenges to building an implantable vascularized solid organ.
Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Animales , Matriz Extracelular , Humanos , Perfusión , Ratas , Medicina Regenerativa , Ingeniería de Tejidos/métodosRESUMEN
The heart is a highly complex, multicellular solid organ with energy-demanding processes that require a dense vascular network, extensive cell-cell interactions, and extracellular matrix (ECM)-mediated crosstalk among heterogeneous cell populations. Here, we describe the regeneration of left ventricular (LV) wall using decellularized whole rabbit heart scaffolds recellularized exclusively with human induced pluripotent stem cell-derived endothelial cells, cardiomyocytes, and other cardiac cell types. Cells were sequentially delivered to the scaffold using an optimized endothelial cell:cardiomyocyte media. Macroscopic assessment after 60 days showed that the LV wall of recellularized hearts was anatomically restored to full thickness from base to apex and endocardium to epicardium. Histologic analysis of the recellularized LV wall revealed a heterogeneous pool of cardiac cells containing aligned cardiac troponin T-positive cells in close contact with ECM; vessels varied from large artery-like, surrounded by smooth muscle actin+ cells, to capillary-like. Vessel patency was demonstrated after perfusion of recellularized hearts transplanted into the femoral artery bed of a pig. The construct exhibited visible beating and responded to chronotropic drug administration. These results demonstrate the ability to tissue engineer a vascularized, full-thickness LV wall with an unparalleled level of microanatomical organization and multicellular composition, using decellularized ECM and human cardiomyocytes, endothelial cells, and other cardiac cell types. STATEMENT OF SIGNIFICANCE: Decellularized extracellular matrix (ECM) is a bioactive template for tissue engineering, but recellularizing acellular whole heart scaffolds is challenging. Here, we successfully revascularized and repopulated a large, full-thickness portion of a ventricle using human induced pluripotent stem cell-derived endothelial and cardiac cells. At 60 days, histologic studies showed that the microanatomical organization and cellular composition of this region was similar to that of the native heart. The recellularized heart showed visible beating and responded appropriately to heartbeat-altering drugs. Vessels surrounded by smooth muscle cells and endothelial cells supported blood flow through the vessels of a recellularized heart that was surgically connected to a pig femoral artery. These findings move this approach closer to the possibility of clinical translation.
Asunto(s)
Células Madre Pluripotentes Inducidas , Animales , Bioingeniería , Células Endoteliales/trasplante , Ventrículos Cardíacos , Humanos , Miocitos Cardíacos , Conejos , Porcinos , Andamios del TejidoRESUMEN
BACKGROUND: Sex and hormones influence immune responses to ischemia reperfusion (IR) and could, therefore, cause sex-related differences in lung transplantation (LTx) outcomes. We compared men's and women's clinical and molecular responses to post-LTx IR. METHODS: In 203 LTx patients, we used the 2016 International Society for Heart and Lung Transplantation guidelines to score primary graft dysfunction (PGD). In a subgroup of 40 patients with blood samples collected before LTx (T0) and 6, 24, 48 (T48), and 72 h (T72) after lung reperfusion, molecular response to IR was examined through serial analysis of circulating cytokine expression. RESULTS: After adjustment, women had less grade 3 PGD than men at T48, but not at T72. PGD grade decreased from T0 to T72 more often in women than men. The evolution of PGD (the difference in mean PGD between T72 and T0) was greater in men. However, the evolution of IL-2, IL-7, IL-17a, and basic fibroblast growth factor levels was more often sustained throughout the 72 h in women. In the full cohort, we noted no sex differences in secondary clinical outcomes, but women had significantly lower peak lactate levels than men across the 72 h. CONCLUSIONS: Men and women differ in the evolution of PGD and cytokine secretion after LTx: Women have a more sustained proinflammatory response than men despite a greater reduction in PGD over time. This interaction between cytokine and PGD responses warrants investigation. Additionally, there may be important sex-related differences that could be used to tailor treatment during or after transplantation.