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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1617-1622, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627450

RESUMO

OBJECTIVE: To establish a mouse model of respiratory syncytial virus (RSV) infection after hematopoietic stem cell transplantation, so as to lay the foundation for future research on RSV infection and related complications after hematopoietic stem cell transplantation. METHODS: Bone marrow cells and spleen cells were transplanted to C57BL/6 mice after myeloablative treatment to establish a mouse model of allogeneic hematopoietic stem cell transplantation. The chimerism rate was detected by flow cytometry 3 and 7 weeks after transplantation. The transplanted mice were infected with RSV by nasal drops. The lung tissues were collected 5 days after infection for identification of infection, and lung tissues were analyzed for pathology 2 weeks and 2 months after infection. RESULTS: The chimerism rate was > 90% at 3 and 7 weeks after transplantation. Successful infection was detected 5 days after RSV infection, and there were severe and persistent pathological changes in the lung tissues of the mice 2 weeks and 2 months after infection. CONCLUSION: RSV infection in stable chimeric mice after hematopoietic stem cell transplantation can cause significantly persistent lung disease, which lays foundation for the prevention and treatment of RSV infection and the mechanism of later bronchiolitis obliterans after hematopoietic stem cell transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Vírus Sincicial Respiratório Humano , Animais , Quimerismo , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
2.
Nat Commun ; 12(1): 4706, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349112

RESUMO

During mammalian pregnancy, immune cells are vertically transferred from mother to fetus. The functional role of these maternal microchimeric cells (MMc) in the offspring is mostly unknown. Here we show a mouse model in which MMc numbers are either normal or low, which enables functional assessment of MMc. We report a functional role of MMc in promoting fetal immune development. MMc induces preferential differentiation of hematopoietic stem cells in fetal bone marrow towards monocytes within the myeloid compartment. Neonatal mice with higher numbers of MMc and monocytes show enhanced resilience against cytomegalovirus infection. Similarly, higher numbers of MMc in human cord blood are linked to a lower number of respiratory infections during the first year of life. Our data highlight the importance of MMc in promoting fetal immune development, potentially averting the threats caused by early life exposure to pathogens.


Assuntos
Quimerismo , Feto/imunologia , Imunidade Materno-Adquirida/imunologia , Infecções/imunologia , Animais , Medula Óssea/metabolismo , Epigenoma , Feminino , Sangue Fetal/citologia , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Lactente , Camundongos , Monócitos/citologia , Gravidez , Linfócitos T/citologia
3.
Hum Reprod ; 36(9): 2529-2537, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34293108

RESUMO

STUDY QUESTION: Does having a male co-twin, older brothers, or sons lead to an increased probability of persistent male microchimerism in female members of twin pedigrees? SUMMARY ANSWER: The presence of a male co-twin did not increase risk of male microchimerism and the prevalence of male microchimerism was not explained by having male offspring or by having an older brother. WHAT IS KNOWN ALREADY: Microchimerism describes the presence of cells within an organism that originate from another zygote and is commonly described as resulting from pregnancy in placental mammals. It is associated with diseases with a female predilection including autoimmune diseases and pregnancy-related complications. However, microchimerism also occurs in nulliparous women; signifying gaps in the understanding of risk factors contributing to persistent microchimerism and the origin of the minor cell population. STUDY DESIGN, SIZE, DURATION: This cross-sectional study composed of 446 adult female participants of the Netherlands Twin Register (NTR). PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants included in the study were female monozygotic (MZ) twins, female dizygotic same-sex twins and females of dizygotic opposite-sex twin pairs, along with the mothers and sisters of these twins. Peripheral blood samples collected from adult female participants underwent DNA extraction and were biobanked prior to the study. To detect the presence of male-origin microchimerism, DNA samples were tested for the relative quantity of male specific Y chromosome gene DYS14 compared to a common ß-globin gene using a highly sensitive quantitative PCR assay. MAIN RESULTS AND THE ROLE OF CHANCE: We observed a large number of women (26.9%) having detectable male microchimerism in their peripheral blood samples. The presence of a male co-twin did not increase risk of male microchimerism (odds ratio (OR) = 1.23: SE 0.40, P = 0.61) and the prevalence of male microchimerism was not explained by having male offspring (OR 0.90: SE 0.19, P = 0.63) or by having an older brother (OR = 1.46: SE 0.32, P = 0.09). The resemblance (correlation) for the presence of microchimerism was similar (P = 0.66) in MZ pairs (0.27; SE 0.37) and in first-degree relatives (0.091; SE 0.092). However, age had a positive relationship with the presence of male microchimerism (P = 0.02). LIMITATIONS, REASONS FOR CAUTION: After stratifying for variables of interest, some participant groups resulted in a low numbers of subjects. We investigated microchimerism in peripheral blood due to the proposed mechanism of cell acquisition via transplacental blood exchange; however, this does not represent global chimerism in the individual and microchimerism may localize to numerous other tissues. WIDER IMPLICATIONS OF THE FINDINGS: Immune regulation during pregnancy is known to mitigate allosensitization and support tolerance to non-inherited antigens found on donor cells. While unable to identify a specific source that promotes microchimerism prevalence within pedigrees, this study points to the underlying complexities of natural microchimerism in the general population. These findings support previous studies which have identified the presence of male microchimerism among women with no history of pregnancy, suggesting alternative sources of microchimerism. The association of detectable male microchimerism with age is suggestive of additional factors including time, molecular characteristics and environment playing a critical role in the prevalence of persistent microchimerism. The present study necessitates investigation into the molecular underpinnings of natural chimerism to provide insight into women's health, transplant medicine and immunology. STUDY FUNDING/COMPETING INTEREST(S): This work is funded by Royal Netherlands Academy of Science Professor Award (PAH/6635 to D.I.B.); The Netherlands Organisation for Health Research and Development (ZonMw)-Genotype/phenotype database for behavior genetic and genetic epidemiological studies (ZonMw 911-09-032); Biobanking and Biomolecular Research Infrastructure (BBMRI-NL, 184.021.007; 184.033.111); The Netherlands Organisation for Scientific Research (NWO)-Netherlands Twin Registry Repository (NWO-Groot 480-15-001/674); the National Institutes of Health-The Rutgers University Cell and DNA Repository cooperative agreement (NIMH U24 MH068457-06), Grand Opportunity grants Integration of genomics and transcriptomics in normal twins and major depression (NIMH 1RC2 MH089951-01), and Developmental trajectories of psychopathology (NIMH 1RC2 MH089995); and European Research Council-Genetics of Mental Illness (ERC 230374). C.B.L. declares a competing interest as editor-in-chief of Human Reproduction and his department receives unrestricted research grants from Ferring, Merck and Guerbet. All remaining authors have no conflict-of-interest to declare in regards to this work. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Bancos de Espécimes Biológicos , Quimerismo , Estudos Transversais , Feminino , Humanos , Masculino , Linhagem , Placenta , Gravidez , Estados Unidos
4.
Transplant Cell Ther ; 27(8): 642-649, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34304802

RESUMO

Allogeneic hematopoietic cell transplantation (allo-HCT) is potentially curative for certain hematologic malignancies and nonmalignant diseases. The field of allo-HCT has witnessed significant advances, including broadening indications for transplantation, availability of alternative donor sources, less toxic preparative regimens, new cell manipulation techniques, and novel GVHD prevention methods, all of which have expanded the applicability of the procedure. These advances have led to clinical practice conundrums when applying traditional definitions of hematopoietic recovery, graft rejection, graft failure, poor graft function, and donor chimerism, because these may vary based on donor type, cell source, cell dose, primary disease, graft-versus-host disease (GVHD) prophylaxis, and conditioning intensity, among other variables. To address these contemporary challenges, we surveyed a panel of allo-HCT experts in an attempt to standardize these definitions. We analyzed survey responses from adult and pediatric transplantation physicians separately. Consensus was achieved for definitions of neutrophil and platelet recovery, graft rejection, graft failure, poor graft function, and donor chimerism, but not for delayed engraftment. Here we highlight the complexities associated with the management of mixed donor chimerism in malignant and nonmalignant hematologic diseases, which remains an area for future research. We recognize that there are multiple other specific, and at times complex, clinical scenarios for which clinical management must be individualized.


Assuntos
Quimerismo , Transplante de Células-Tronco Hematopoéticas , Adulto , Criança , Rejeição de Enxerto/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Condicionamento Pré-Transplante , Transplante Homólogo , Estados Unidos
5.
Twin Res Hum Genet ; 24(3): 184-186, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34127172

RESUMO

We report a very rare case of monochorionic dizygotic twins conceived spontaneously. The fetuses were sex-discordant in ultrasonography despite being monochorionic twins. After birth, the girl and boy showed normal phenotypes but they showed blood chimerism in karyotype and blood group type.


Assuntos
Antígenos de Grupos Sanguíneos , Gêmeos Dizigóticos , Quimerismo , Feminino , Humanos , Cariótipo , Cariotipagem , Masculino , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
6.
Transplant Cell Ther ; 27(9): 780.e1-780.e14, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34082161

RESUMO

The impact of donor-host chimerism in post-hematopoietic stem cell transplantation (HSCT) outcomes is poorly understood. We were interested in studying whether pre-HSCT variables influenced lineage-specific donor-host chimerism and how lineage-specific chimerism impacts post-HSCT outcomes. Our main objective was to study pre-HSCT variables as predictors of lineage-specific donor-host chimerism patterns and to better characterize the relationship between post-HSCT lineage-specific chimerism and adverse outcomes, including graft failure and disease relapse. We conducted a retrospective data analysis of all patients who underwent allogeneic HSCT at the Pediatric Transplantation and Cellular Therapy service at Memorial Sloan Kettering Cancer Center between January 2010 and June 2015 and had at least 2 measurements of split-lineage chimerism. The trend of lineage-specific donor-host chimerism post-HSCT and the impact of age, disease, graft type, and pretransplantation conditioning regimen on chimerism at 3 months and 12 months post-HSCT were studied. The Wilcoxon signed-rank test, Mann-Whitney-Wilcoxon test, and Cox proportional hazard models were used for statistical analyses. A total of 137 patients were included (median age, 11.3 years). Most patients had a hematologic malignancy (n = 95), and fewer had a nonmalignant disorder (n = 27) or primary immune deficiency (n = 15). Myeloablative conditioning regimens (n = 126) followed by T cell-depleted (TCD) peripheral blood stem cell or bone marrow grafts (n = 101) were most commonly used. Mixed chimerism (MC) of total peripheral blood leukocytes (PBLs) did not predict loss of donor chimerism in all lineages and when stable was not associated with graft failure or rejection in this analyses. Split chimerism with complete donor chimerism (CC) of myeloid, B, and natural killer cells, but not T cells, occurred early post-HSCT, but full donor T cell chimerism was achieved at 12 months post-HSCT by most patients. MC within the T cell lineage was the major contributor to PBL MC, with lower median donor T cell chimerism at 3 months than at 12 months (91%) post-HSCT (51% versus 91%; P < .0001). Predictors of MC at 3 and 12 months were (1) age <3 years (P = .01 for PBLs and P = .003 for myeloid lineage); (2) nonmalignant disorder (P = .007 for PBLs); and (3) the use of reduced-intensity conditioning regimens. TCD grafts produced lower donor T cell chimerism at 3 months post-HSCT compared with unmodified grafts (P < .0001), where T cell lineage CC was achieved early post-HSCT. The donor T cell chimerism was similar at 12 months in the 2 types of grafts. Umbilical cord blood grafts had CC in all lineages at all time points post-HSCT. Loss of donor B cell chimerism was associated with increased risk of relapse in hematologic malignancies (hazard ratio, 1.33; P = .05). Age, underlying disease, conditioning regimen, and graft manipulation can impact post-HSCT donor-host chimerism and be predictors for early MC. MC in total PBLs and T cells was not related to graft failure or disease relapse. Whole-blood PBL chimerism analysis is not sufficient to assess the significance of post-HSCT donor-host status; rather, lineage-specific chimerism, particularly for myeloid, T, and B cells, should be analyzed to guide interventions and inform outcomes.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criança , Pré-Escolar , Quimerismo , Humanos , Lactente , Recidiva Local de Neoplasia , Estudos Retrospectivos , Transplante Homólogo
7.
Hematology ; 26(1): 435-443, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34130602

RESUMO

A retrospective study on 287 patients with SAA who underwent allo-HSCT between October 2012 and January 2020 was conducted to explore the outcomes, risk factors and treatment options for MC. Among 287 AA patients who excluded Fanconi anemia (FA), Congenital dyskeratosis (DKC), Paroxysmal nocturnal hemoglobinuria (PNH), etc.112 underwent matched sibling donor (MSD)-HSCT, 91 matched unrelated donor-HSCT and 84 haploidentical-HSCT. Patients were divided into the following 4 groups: group 1: Donor chimerism (DC); group 2: MC without cytopenia; group 3: MC with cytopenia; group 4: secondary graft failure (SGF).Compared with the other three groups, SGF predicted a poor prognosis of SAA (P< 0.001). In addition, SGF was associated with the early (within 3 months after transplantation) presence of MC and the high levels of MC. Uni- and multivariate logistic regression analysis showed that donor/recipient sex-mismatching and CTX + ATG regimen were high-risk factors for MC. Of note, in MC patients with cytopenia (group 3), the effective response rate reached 55% (6/11) following enhanced immunosuppression combined with cellular therapy, while only one of the four was effective who received enhanced immunosuppression alone.SGF was associated with poor prognosis, early presence of MC and increased levels of recipient chimerism. The donor/recipient sex-mismatching and CTX + ATG regimen based MSD-HSCT were risk factors for MC. Cellular therapy could improve the effective response rate of patients with progressive MC.


Assuntos
Anemia Aplástica/terapia , Quimerismo , Transplante de Células-Tronco Hematopoéticas , Adulto , Anemia Aplástica/diagnóstico , Anemia Aplástica/genética , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Transplante Homólogo/efeitos adversos
8.
Sci Rep ; 11(1): 13437, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183759

RESUMO

Whole organ perfusion decellularization has been proposed as a promising method to generate non-immunogenic organs from allogeneic and xenogeneic donors. However, the ability to recellularize organ scaffolds with multiple patient-specific cells in a spatially controlled manner remains challenging. Here, we propose that replacing donor endothelial cells alone, while keeping the rest of the organ viable and functional, is more technically feasible, and may offer a significant shortcut in the efforts to engineer transplantable organs. Vascular decellularization was achieved ex vivo, under controlled machine perfusion conditions, in various rat and porcine organs, including the kidneys, liver, lungs, heart, aorta, hind limbs, and pancreas. In addition, vascular decellularization of selected organs was performed in situ, within the donor body, achieving better control over the perfusion process. Human placenta-derived endothelial progenitor cells (EPCs) were used as immunologically-acceptable human cells to repopulate the luminal surface of de-endothelialized aorta (in vitro), kidneys, lungs and hind limbs (ex vivo). This study provides evidence that artificially generating vascular chimerism is feasible and could potentially pave the way for crossing the immunological barrier to xenotransplantation, as well as reducing the immunological burden of allogeneic grafts.


Assuntos
Células Endoteliais/citologia , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Tecidos Suporte , Quimeras de Transplante/anatomia & histologia , Transplante Heterólogo/métodos , Animais , Quimerismo , Feminino , Membro Posterior/irrigação sanguínea , Membro Posterior/transplante , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Suínos , Coleta de Tecidos e Órgãos , Vísceras/irrigação sanguínea , Vísceras/transplante
9.
Front Immunol ; 12: 637512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017327

RESUMO

The aim of this review is to update the current status of allogeneic hemopoietic stem cell transplants (HSCT) for patients with myelofibrosis (MF). We have first summarized the issue of an indication for allogeneic HSCT, discussing several prognostic scoring systems, developed to predict the outcome of MF, and therefore to identify patients who will benefit of an allogeneic HSCT. Patients with low risk MF are usually not selected for a transplant, whereas patients with intermediate or high risk MF are eligible. A separate issue, is how to predict the outcome of HSCT: we will outline a clinical molecular myelofibrosis transplant scoring system (MTSS), which predicts overall survival, ranging from 90% for low risk patients, to 20% for very high risk patients. We will also discuss transfusion burden and spleen size, as predictors of transplant outcome. The choice of a transplant platform including the conditioning regimen, the stem cell source and GvHD prophylaxis, are crucial for a successful program in MF, and will be outlined. Complications such as poor graft function, graft failure, GvHD and relapse of the disease, will also be reviewed. Finally we discuss monitoring the disease after HSCT with donor chimerism, driver mutations and hematologic data. We have made an effort to make this review as comprehensive and up to date as possible, and we hope it will provide some useful data for the clinicians.


Assuntos
Rejeição de Enxerto/prevenção & controle , Reação Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas , Mielofibrose Primária/terapia , Animais , Quimerismo , Humanos , Tolerância Imunológica , Condicionamento Pré-Transplante , Transplante Homólogo
11.
Am J Med Genet C Semin Med Genet ; 187(2): 235-239, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33982348

RESUMO

Mythical figures have been part of human cultural tradition for centuries, worldwide. Some of them were totally imaginary, others were likely inspired by individuals with malformation syndromes, while others are composites of parts of different species. Various artists have created works of art based on these mythical or hybrid beings, such as cyclops and chimeras. The plethora of representations of artworks in ancient, but also contemporary art (statues, paintings, illustrations, photographs, installations) is proof that they still continue to be a source of inspiration, although their rendering and interpretation have changed over time. Contemporary medical genetic knowledge has revealed the underlying pathogenesis and causative molecular basis of malformation syndromes and delineates the corresponding phenotypes. Today, many figures once viewed as mythical are reflected in living humans with medical diagnoses. Ancient terms that arose in mythology-cyclopia, chimera/ism, and others-live on in the medical literature.


Assuntos
Anormalidades Múltiplas , Holoprosencefalia , Quimerismo , Humanos , Mitologia
12.
Front Immunol ; 12: 652105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968052

RESUMO

Transplantation of allogeneic hematopoietic cells faces two barriers: failure of engraftment due to a host versus graft reaction, and the attack of donor cells against the patient, the graft versus host (GVH) reaction. This reaction may lead to GVH disease (GVHD), but in patients transplanted due to leukemia or other malignant disorders, this may also convey the benefit of a graft versus leukemia (GVL) effect. The interplay of transplant conditioning with donor and host cells and the environment in the patient is complex. The microbiome, particularly in the intestinal tract, profoundly affects these interactions, directly and via soluble mediators, which also reach other host organs. The microenvironment is further altered by the modifying effect of malignant cells on marrow niches, favoring the propagation of the malignant cells. The development of stable mixed donor/host chimerism has the potential of GVHD prevention without necessarily increasing the risk of relapse. There has been remarkable progress with novel conditioning regimens and selective T-cell manipulation aimed at securing engraftment while preventing GVHD without ablating the GVL effect. Interventions to alter the microenvironment and change the composition of the microbiome and its metabolic products may modify graft/host interactions, thereby further reducing GVHD, while enhancing the GVL effect. The result should be improved transplant outcome.


Assuntos
Quimerismo , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Leucemia/terapia , Recidiva Local de Neoplasia/prevenção & controle , Intervalo Livre de Doença , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/imunologia , Reação Enxerto-Hospedeiro/efeitos dos fármacos , Reação Enxerto-Hospedeiro/genética , Reação Enxerto-Hospedeiro/imunologia , Efeito Enxerto vs Leucemia/genética , Efeito Enxerto vs Leucemia/imunologia , Humanos , Leucemia/genética , Leucemia/imunologia , Leucemia/mortalidade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/imunologia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/efeitos adversos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
13.
Front Immunol ; 12: 651399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968049

RESUMO

Background: Cord blood (CB) samples are increasingly used as a source of hematopoietic stem cells in transplantation settings. Maternal cells have been detected in CB samples and their presence is associated with a better graft outcome. However, we still do not know what influences the presence of maternal microchimerism (MMc) in CB samples and whether their presence influences CB hematopoietic cell composition. Patients and Methods: Here we test whether genetic, biological, anthropometric and/or obstetrical parameters influence the frequency and/or quantity of maternal Mc in CB samples from 55 healthy primigravid women. Mc was evaluated by targeting non-shared, non-inherited Human Leukocyte Antigen (HLA)-specific real-time quantitative PCR in whole blood and four cell subsets (T, B lymphocytes, granulocytes and/or hematopoietic progenitor cells). Furthermore CB samples were analyzed for their cell composition by flow cytometry and categorized according to their microchimeric status. Results: MMc was present in 55% of CB samples in at least one cell subset or whole blood, with levels reaching up to 0.3% of hematopoietic progenitor cells. Two factors were predictive of the presence of MMc in CB samples: high concentrations of maternal serological Pregnancy-Associated-Protein-A at first trimester of pregnancy (p=0.018) and feto-maternal HLA-A and/or -DR compatibility (p=0.009 and p=0.01 respectively). Finally, CB samples positive for MMc were significantly enriched in CD56+ cells compared to CB negative for MMc. Conclusions: We have identified two factors, measurable at early pregnancy, predicting the presence of maternal cells in CB samples at delivery. We have shown that MMc in CB samples could have an influence on the hematopoietic composition of fetal cells. CD56 is the phenotypic marker of natural killer cells (NK) and NK cells are known to be the main effector for graft versus leukemia reactions early after hematopoietic stem cell transplantation. These results emphasize the importance of MMc investigation for CB banking strategies.


Assuntos
Quimerismo , Sangue Fetal/citologia , Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais/imunologia , Troca Materno-Fetal/imunologia , Adulto , Antígeno CD56/análise , Antígeno CD56/metabolismo , Separação Celular , Feminino , Sangue Fetal/imunologia , Citometria de Fluxo , Humanos , Recém-Nascido , Células Matadoras Naturais/metabolismo , Masculino , Idade Materna , Gravidez , Adulto Jovem
14.
Cell ; 184(8): 2020-2032.e14, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33861963

RESUMO

Interspecies chimera formation with human pluripotent stem cells (hPSCs) represents a necessary alternative to evaluate hPSC pluripotency in vivo and might constitute a promising strategy for various regenerative medicine applications, including the generation of organs and tissues for transplantation. Studies using mouse and pig embryos suggest that hPSCs do not robustly contribute to chimera formation in species evolutionarily distant to humans. We studied the chimeric competency of human extended pluripotent stem cells (hEPSCs) in cynomolgus monkey (Macaca fascicularis) embryos cultured ex vivo. We demonstrate that hEPSCs survived, proliferated, and generated several peri- and early post-implantation cell lineages inside monkey embryos. We also uncovered signaling events underlying interspecific crosstalk that may help shape the unique developmental trajectories of human and monkey cells within chimeric embryos. These results may help to better understand early human development and primate evolution and develop strategies to improve human chimerism in evolutionarily distant species.


Assuntos
Quimerismo , Embrião de Mamíferos/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Embrião de Mamíferos/metabolismo , Feminino , Humanos , Macaca fascicularis , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/transplante , RNA-Seq , Análise de Célula Única , Transcriptoma
15.
Transplant Proc ; 53(4): 1360-1364, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33888344

RESUMO

Acute myeloid leukemia (AML) is a rare malignancy with increased incidence in the kidney transplantation (KT) population for which immunosuppression has been implicated as a putative cause. The average time interval from KT to AML development is 5 years. We present the case of a 61-year-old man who was found to have peripheral blood blasts on a postoperative day 20 routine blood draw after an uneventful unrelated living donor kidney transplant. He subsequently had a bone marrow biopsy and next-generation sequencing (NGS)-based molecular testing, which demonstrated AML characterized by SMC1A and TET2 mutations. He received induction chemotherapy followed by hematopoietic cell transplantation (HCT) from the kidney donor, who happened to be matched at one haplotype. At 12 months after his HCT and 15 months after his KT, his AML remained in remission, normal renal function was preserved, no active graft-versus-host disease was present, and immunosuppression was tapering. With full donor-derived hematopoietic chimerism, we expect to be able to discontinue immunosuppression shortly, thereby achieving tolerance. The short time interval between KT and development of AML suggests the malignancy was likely present before KT. Modern NGS-based analysis offers a promising method of identifying transplant candidates with unexplained hematologic abnormalities on pre-KT testing who may benefit from formal hematologic evaluation.


Assuntos
Transplante de Rim/efeitos adversos , Leucemia Mieloide Aguda/diagnóstico , Medula Óssea/patologia , Proteínas de Ciclo Celular/genética , Quimerismo , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Doença Enxerto-Hospedeiro/etiologia , Haplótipos , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas/genética , Indução de Remissão
16.
Transplant Cell Ther ; 27(4): 316.e1-316.e8, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33836874

RESUMO

Immune-mediated cytopenias (IMC)-isolated or combined hemolytic anemia, thrombocytopenia, or neutropenia-are increasingly recognized as serious complications after allogeneic hematopoietic cell transplantation (HCT) for nonmalignant disorders (NMD). However, IMC incidence, duration, response to therapy, and risk factors are not well defined. This retrospective chart review identified cases of IMC with serologic confirmation among patients who underwent HCT for NMD at a single institution between 2010 and 2017. IMC after HCT for NMD in a large pediatric cohort (n = 271) was common with a cumulative incidence of 18%, identified at a median of 136 days after HCT. Treatment included prolonged immune suppression (>3 months) in 58% of all IMC cases, 91% when multiple cell lines were affected. Multiple therapeutic agents were used for the majority affected, and median time to resolution of IMC was 118 days from diagnosis. Fine-Gray competing risk multivariate regression analysis identified a combined risk factor of younger age (<3 years) and inherited metabolic disorder, as well as hemoglobinopathy (at any age) associated with 1-year incidence of IMC (P < .01). We expand these findings with the observation of declining donor T-lymphoid chimerism from day 60 to 100 and lower absolute CD4+ counts at day 100 (P < .01), before median onset of IMC, for patients with IMC compared to those without. In this cohort, 4 deaths (8%) were associated with IMC, including 2 requiring second transplantation for secondary graft failure. Although the pathogenesis of IMC post-HCT for NMD remains elusive, further research may identify approaches to prevent and better treat this HCT complication.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Trombocitopenia , Criança , Pré-Escolar , Quimerismo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Estudos Retrospectivos , Condicionamento Pré-Transplante
17.
Xenotransplantation ; 28(4): e12691, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33904221

RESUMO

BACKGROUND: A major obstacle to the success of organ transplantation from pigs to humans, necessitated by the shortage of human organs, is robust humoral immune rejection by pig-reactive human antibodies. Mixed xenogeneic hematopoietic chimerism induces xenoreactive B cell tolerance in rodents, but whether mixed pig/human chimerism could induce tolerance of human B cells to pig xenoantigens is unknown. METHODS: We investigated this question using a humanized mouse model in which durable mixed (pig-human) xenogeneic chimerism can be established. RESULTS: Human natural anti-pig cytotoxic antibodies, predominantly IgM, are detectable in non-chimeric humanized mouse serum, and pig-reactive antibodies were reduced in mixed chimeric versus non-chimeric humanized mice. This difference required persistent mixed chimerism and was not due to the adsorption of antibodies on pig cells in vivo. Furthermore, human B cells from spleens of mixed chimeric mice produced lower levels of anti-pig antibodies when stimulated in vitro compared with those from non-chimeric mice. CONCLUSIONS: Our findings demonstrate that mixed chimerism reduces human natural antibodies to pig xenoantigens, providing the first in vivo evidence of human B cell tolerance induction by mixed xenogeneic chimerism and supporting further evaluation of this approach for inducing human B cell tolerance to xenografts.


Assuntos
Quimerismo , Tolerância Imunológica , Animais , Antígenos Heterófilos , Linfócitos B , Transplante de Medula Óssea , Humanos , Camundongos , Suínos , Transplante Heterólogo
18.
Front Immunol ; 12: 607282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854497

RESUMO

Over the past decade, immunotherapies have revolutionized the treatment of cancer. Although the success of immunotherapy is remarkable, it is still limited to a subset of patients. More than 1500 clinical trials are currently ongoing with a goal of improving the efficacy of immunotherapy through co-administration of other agents. Preclinical, small-animal models are strongly desired to increase the pace of scientific discovery, while reducing the cost of combination drug testing in humans. Human immune system (HIS) mice are highly immune-deficient mouse recipients rtpeconstituted with human hematopoietic stem cells. These HIS-mice are capable of growing human tumor cell lines and patient-derived tumor xenografts. This model allows rapid testing of multiple, immune-related therapeutics for tumors originating from unique clinical samples. Using a cord blood-derived HIS-BALB/c-Rag2nullIl2rγnullSIRPαNOD (BRGS) mouse model, we summarize our experiments testing immune checkpoint blockade combinations in these mice bearing a variety of human tumors, including breast, colorectal, pancreatic, lung, adrenocortical, melanoma and hematological malignancies. We present in-depth characterization of the kinetics and subsets of the HIS in lymph and non-lymph organs and relate these to protocol development and immune-related treatment responses. Furthermore, we compare the phenotype of the HIS in lymph tissues and tumors. We show that the immunotype and amount of tumor infiltrating leukocytes are widely-variable and that this phenotype is tumor-dependent in the HIS-BRGS model. We further present flow cytometric analyses of immune cell subsets, activation state, cytokine production and inhibitory receptor expression in peripheral lymph organs and tumors. We show that responding tumors bear human infiltrating T cells with a more inflammatory signature compared to non-responding tumors, similar to reports of "responding" patients in human immunotherapy clinical trials. Collectively these data support the use of HIS mice as a preclinical model to test combination immunotherapies for human cancers, if careful attention is taken to both protocol details and data analysis.


Assuntos
Modelos Animais de Doenças , Xenoenxertos , Sistema Imunitário , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Animais , Quimerismo , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunoterapia/efeitos adversos , Imunoterapia/métodos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias/etiologia , Fenótipo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
PLoS Comput Biol ; 17(3): e1008778, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33647016

RESUMO

Human pluripotent stem cells hold significant promise for regenerative medicine. However, long differentiation protocols and immature characteristics of stem cell-derived cell types remain challenges to the development of many therapeutic applications. In contrast to the slow differentiation of human stem cells in vitro that mirrors a nine-month gestation period, mouse stem cells develop according to a much faster three-week gestation timeline. Here, we tested if co-differentiation with mouse pluripotent stem cells could accelerate the differentiation speed of human embryonic stem cells. Following a six-week RNA-sequencing time course of neural differentiation, we identified 929 human genes that were upregulated earlier and 535 genes that exhibited earlier peaked expression profiles in chimeric cell cultures than in human cell cultures alone. Genes with accelerated upregulation were significantly enriched in Gene Ontology terms associated with neurogenesis, neuron differentiation and maturation, and synapse signaling. Moreover, chimeric mixed samples correlated with in utero human embryonic samples earlier than human cells alone, and acceleration was dose-dependent on human-mouse co-culture ratios. The altered gene expression patterns and developmental rates described in this report have implications for accelerating human stem cell differentiation and the use of interspecies chimeric embryos in developing human organs for transplantation.


Assuntos
Quimerismo , Células-Tronco Embrionárias Humanas , Neurogênese , Células-Tronco Pluripotentes , Animais , Células Cultivadas , Biologia Computacional , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/fisiologia , Humanos , Camundongos , Neurogênese/genética , Neurogênese/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia , Especificidade da Espécie , Transcriptoma/genética
20.
Bone Marrow Transplant ; 56(8): 1818-1827, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33658643

RESUMO

Despite advances in gene therapy allogeneic hematopoietic stem cell transplants (HSCT) remains the most effective way to cure sickle cell disease (SCD). However, there are substantial challenges including lack of suitable donors, therapy-related toxicity (TRM) and risk of graft-versus-host disease (GvHD). Perhaps the most critical question is when to do a transplant for SCD. Safer transplant protocols for HLA-disparate HSCT is needed before transplants are widely accepted for SCD. Although risk of GvHD and TRM are less with T-cell-deplete HSCT and reduced-intensity conditioning (RIC), transplant rejection is a challenge. We have reported graft rejection of T cell-depleted non-myeloablative HSCT can be overcome in wild type fully mis-matched recipient mice, using donor-derived anti-3rd party central memory CD8-positive veto cells combined with short-term low-dose rapamycin. Here, we report safety and efficacy of this approach in a murine model for SCD. Durable donor-derived chimerism was achieved using this strategy with reversal of pathological parameters of SCD, including complete conversion to normal donor-derived red cells, and correction of splenomegaly and the levels of circulating reticulocytes, hematocrit, and hemoglobin.


Assuntos
Anemia Falciforme , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Anemia Falciforme/terapia , Animais , Quimerismo , Doença Enxerto-Hospedeiro/prevenção & controle , Camundongos , Condicionamento Pré-Transplante
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