RESUMO
Worldwide, each year over 30,000 patients undergo an allogeneic hema-topoietic stem cell transplantation with the intent to cure high-risk hematologic malignancy, immunodeficiency, metabolic disease, or a life-threatening bone marrow failure syndrome. Despite substantial advances in donor selection and conditioning regimens and greater availability of allograft sources, transplant recipients still endure the morbidity and mortality of graft-versus-host disease (GVHD). Herein, we identify key aspects of acute and chronic GVHD pathophysiology, including host/donor cell effectors, gut dysbiosis, immune system and cytokine imbalance, and the interface between inflammation and tissue fibrosis. In particular, we also summarize the translational application of this heightened understanding of immune dysregulation in the design of novel therapies to prevent and treat GVHD.
Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Animais , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Condicionamento Pré-Transplante , Transplante HomólogoRESUMO
The intestinal microbiota is an important modulator of graft-versus-host disease (GVHD), which often complicates allogeneic hematopoietic stem cell transplantation (allo-HSCT). Broad-spectrum antibiotics such as carbapenems increase the risk for intestinal GVHD, but mechanisms are not well understood. In this study, we found that treatment with meropenem, a commonly used carbapenem, aggravates colonic GVHD in mice via the expansion of Bacteroides thetaiotaomicron (BT). BT has a broad ability to degrade dietary polysaccharides and host mucin glycans. BT in meropenem-treated allogeneic mice demonstrated upregulated expression of enzymes involved in the degradation of mucin glycans. These mice also had thinning of the colonic mucus layer and decreased levels of xylose in colonic luminal contents. Interestingly, oral xylose supplementation significantly prevented thinning of the colonic mucus layer in meropenem-treated mice. Specific nutritional supplementation strategies, including xylose supplementation, may combat antibiotic-mediated microbiome injury to reduce the risk for intestinal GVHD in allo-HSCT patients.
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Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteroides , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Meropeném , Camundongos , Mucinas/metabolismo , Muco/metabolismo , Polissacarídeos/metabolismo , XiloseRESUMO
Allogeneic T cell expansion is the primary determinant of graft-versus-host disease (GVHD), and current dogma dictates that this is driven by histocompatibility antigen disparities between donor and recipient. This paradigm represents a closed genetic system within which donor T cells interact with peptide-major histocompatibility complexes (MHCs), though clonal interrogation remains challenging due to the sparseness of the T cell repertoire. We developed a Bayesian model using donor and recipient T cell receptor (TCR) frequencies in murine stem cell transplant systems to define limited common expansion of T cell clones across genetically identical donor-recipient pairs. A subset of donor CD4+ T cell clonotypes differentially expanded in identical recipients and were microbiota dependent. Microbiota-specific T cells augmented GVHD lethality and could target microbial antigens presented by gastrointestinal epithelium during an alloreactive response. The microbiota serves as a source of cognate antigens that contribute to clonotypic T cell expansion and the induction of GVHD independent of donor-recipient genetics.
Assuntos
Doença Enxerto-Hospedeiro , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/microbiologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T CD4-Positivos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Microbiota/imunologia , Seleção Clonal Mediada por Antígeno , Transplante Homólogo , Teorema de Bayes , Transplante de Células-Tronco/efeitos adversos , Camundongos Endogâmicos BALB C , Microbioma Gastrointestinal/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversosRESUMO
Acute graft-versus-host disease (aGVHD) remains a major limitation of allogeneic stem cell transplantation (SCT), and severe intestinal manifestation is the major cause of early mortality. Intestinal microbiota control MHC class II (MHC-II) expression by ileal intestinal epithelial cells (IECs) that promote GVHD. Here, we demonstrated that genetically identical mice of differing vendor origins had markedly different intestinal microbiota and ileal MHC-II expression, resulting in discordant GVHD severity. We utilized cohousing and antibiotic treatment to characterize the bacterial taxa positively and negatively associated with MHC-II expression. A large proportion of bacterial MHC-II inducers were vancomycin sensitive, and peri-transplant oral vancomycin administration attenuated CD4+ T cell-mediated GVHD. We identified a similar relationship between pre-transplant microbes, HLA class II expression, and both GVHD and mortality in a large clinical SCT cohort. These data highlight therapeutically tractable mechanisms by which pre-transplant microbial taxa contribute to GVHD independently of genetic disparity.
Assuntos
Microbioma Gastrointestinal , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Camundongos , Animais , Vancomicina , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante Homólogo/efeitos adversosRESUMO
The severity of T cell-mediated gastrointestinal (GI) diseases such as graft-versus-host disease (GVHD) and inflammatory bowel diseases correlates with a decrease in the diversity of the host gut microbiome composition characterized by loss of obligate anaerobic commensals. The mechanisms underpinning these changes in the microbial structure remain unknown. Here, we show in multiple specific pathogen-free (SPF), gnotobiotic, and germ-free murine models of GI GVHD that the initiation of the intestinal damage by the pathogenic T cells altered ambient oxygen levels in the GI tract and caused dysbiosis. The change in oxygen levels contributed to the severity of intestinal pathology in a host intestinal HIF-1α- and a microbiome-dependent manner. Regulation of intestinal ambient oxygen levels with oral iron chelation mitigated dysbiosis and reduced the severity of the GI GVHD. Thus, targeting ambient intestinal oxygen levels may represent a novel, non-immunosuppressive strategy to mitigate T cell-driven intestinal diseases.
Assuntos
Gastroenteropatias , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Camundongos , Disbiose , Intestinos/patologia , Doença Enxerto-Hospedeiro/patologiaRESUMO
In allogeneic hematopoietic stem cell transplantation, donor αß T cells attack recipient tissues, causing graft-versus-host disease (GVHD), a major cause of morbidity and mortality. A central question has been how GVHD is sustained despite T cell exhaustion from chronic antigen stimulation. The current model for GVHD holds that disease is maintained through the continued recruitment of alloreactive effectors from blood into affected tissues. Here, we show, using multiple approaches including parabiosis of mice with GVHD, that GVHD is instead primarily maintained locally within diseased tissues. By tracking 1,203 alloreactive T cell clones, we fitted a mathematical model predicting that within each tissue a small number of progenitor T cells maintain a larger effector pool. Consistent with this, we identified a tissue-resident TCF-1+ subpopulation that preferentially engrafted, expanded, and differentiated into effectors upon adoptive transfer. These results suggest that therapies targeting affected tissues and progenitor T cells within them would be effective.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Camundongos , Animais , Linfócitos T , Transplante Homólogo/efeitos adversos , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodosRESUMO
The key sites within the gastrointestinal (GI) tract where T cells mediate effector responses and the impact of these responses on intestinal stem cells (ISCs) remain unclear. Using experimental bone marrow transplantation to model immune-mediated GI damage and 3D imaging to analyze T cell localization, we found that the ISC compartment is the primary intestinal site targeted by T cells after transplantation. Recruitment to the crypt base region resulted in direct T cell engagement with the stem cell compartment and loss of crypt base columnar ISCs, which expressed both MHC classes I and II. Vasculature expressing the adhesion molecule MAdCAM-1 clustered near the crypt base, preferentially regulating crypt compartment invasion and ISC reduction without affecting T cell migration to villi. These findings indicate that allogeneic T cells rapidly access the stem cell niche after transplantation, and this targeted recruitment to the stem cell compartment results in ISC loss during immune-mediated GI damage.
Assuntos
Células-Tronco Adultas/imunologia , Transplante de Medula Óssea , Mucosa Intestinal/imunologia , Nicho de Células-Tronco/imunologia , Linfócitos T/imunologia , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Citotoxicidade Imunológica , Feminino , Humanos , Imageamento Tridimensional , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Modelos Animais , Mucoproteínas , Transplante HomólogoRESUMO
Graft-versus-host disease (GVHD) in the gastrointestinal (GI) tract is the principal determinant of lethality following allogeneic bone marrow transplantation (BMT). Here, we examined the mechanisms that initiate GVHD, including the relevant antigen-presenting cells. MHC class II was expressed on intestinal epithelial cells (IECs) within the ileum at steady state but was absent from the IECs of germ-free mice. IEC-specific deletion of MHC class II prevented the initiation of lethal GVHD in the GI tract. MHC class II expression on IECs was absent from mice deficient in the TLR adaptors MyD88 and TRIF and required IFNγ secretion by lamina propria lymphocytes. IFNγ responses are characteristically driven by IL-12 secretion from myeloid cells. Antibiotic-mediated depletion of the microbiota inhibited IL-12/23p40 production by ileal macrophages. IL-12/23p40 neutralization prevented MHC class II upregulation on IECs and initiation of lethal GVHD in the GI tract. Thus, MHC class II expression by IECs in the ileum initiates lethal GVHD, and blockade of IL-12/23p40 may represent a readily translatable therapeutic strategy.
Assuntos
Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/imunologia , Microbioma Gastrointestinal/imunologia , Doença Enxerto-Hospedeiro/etiologia , Antígenos de Histocompatibilidade Classe II/imunologia , Mucosa Intestinal/imunologia , Animais , Células Apresentadoras de Antígenos/metabolismo , Biomarcadores , Citocinas/metabolismo , Suscetibilidade a Doenças , Feminino , Expressão Gênica , Doença Enxerto-Hospedeiro/mortalidade , Antígenos de Histocompatibilidade Classe II/genética , Íleo/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Estimativa de Kaplan-Meier , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Prognóstico , Regiões Promotoras Genéticas , Transdução de SinaisRESUMO
Plant genomes interact when genetically distinct individuals join, or are joined, together. Individuals can fuse in three contexts: artificial grafts, natural grafts, and host-parasite interactions. Artificial grafts have been studied for decades and are important platforms for studying the movement of RNA, DNA, and protein. Yet several mysteries about artificial grafts remain, including the factors that contribute to graft incompatibility, the prevalence of genetic and epigenetic modifications caused by exchanges between graft partners, and the long-term effects of these modifications on phenotype. Host-parasite interactions also lead to the exchange of materials, and RNA exchange actively contributes to an ongoing arms race between parasite virulence and host resistance. Little is known about natural grafts except that they can be frequent and may provide opportunities for evolutionary innovation through genome exchange. In this review, we survey our current understanding about these three mechanisms of contact, the genomic interactions that result, and the potential evolutionary implications.
Assuntos
Genoma de Planta , Interações Hospedeiro-Parasita/genética , Melhoramento Vegetal/métodos , Plantas/parasitologia , Evolução Biológica , Variação Biológica da População , Quimera , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/fisiologia , Raízes de Plantas/fisiologia , Plantas/genéticaRESUMO
Recent studies report that stem cell therapies have been applied successfully to patients, This has increased anticipations that this regeneration strategy could be a potential method to treat a wide range of intractable diseases some day. Stem cells offer new prospects for the treatment of incurable diseases and for tissue regeneration and repairation because of their unique biological properties. Angiogenesis a key process in tissue regeneration and repairation. Vascularization of organs is one of the main challenges hindering the clinical application of engineered tissues. Efficient production of engineered vascular grafts and vascularized organs is of critical importance for regenerative medicine. In this review, we focus on the types of stem cells that are widely used in tissue engineering and regeneration, as well as their application of these stem cells in the construction of tissue-engineered vascular grafts and vascularization of tissue-engineered organs.
Assuntos
Neovascularização Fisiológica , Alicerces Teciduais , Humanos , Engenharia Tecidual/métodos , Células-Tronco , Medicina Regenerativa , Neovascularização PatológicaRESUMO
AIM: The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia). METHODS: A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate. STRUCTURE: Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.
Assuntos
American Heart Association , Extremidade Inferior , Doença Arterial Periférica , Humanos , Doença Arterial Periférica/terapia , Doença Arterial Periférica/diagnóstico , Extremidade Inferior/irrigação sanguínea , Estados Unidos , Cardiologia/normasRESUMO
This study sought to compare the behavior of Treg subsets displaying different coexpression patterns of Neuropilin-1 (Nrp1) and Helios, under the influence of gut stress unrelated to hematopoietic stem cell transplantation, pretransplantation conditioning, and posttransplant gastrointestinal acute graft versus host disease (GI-aGvHD). Host CD4+/CD25hi/Foxp3+ Treg cells, identified by flow cytometry, were isolated from various tissues of mice affected by these stressors. Expression of CD25, CTLA-4, CD39, OX40, integrin-ß7, LAG3, TGFß/LAP, granzyme-A, -B, and interleukin-10 was compared in four Treg subsets displaying Helios or Nrp1 only, both or none. Fluorescence-activated cell sorter-sorted Treg subsets, displaying markers affected in a conditioning- and GI-aGVHD-restricted manner, were further investigated by transcriptome profiling and T-cell suppression assays. We found that conditioning by irradiation greatly diminished the relative frequency of Helios+/Nrp1+ Treg, shifting the balance toward Helios-/Nrp1- Treg in the host. Upregulation of integrin-ß7 and OX40 occurred in GI-aGvHD-dependent manner in Helios+/Nrp1+ cells but not in Helios-/Nrp1- Treg. Sorted Treg subsets, confirmed to overexpress Nrp1, Helios, OX40, or integrin-ß7, displayed superior immunosuppressive activity and enrichment in activation-related messenger RNA transcripts. Our data suggest that conditioning-induced shrinkage of the Nrp1+/Helios+ Treg subset may contribute to the development of GI-GvHD by impairing gut homing and decreasing the efficiency of Treg-mediated immunosuppression.
Assuntos
Doença Enxerto-Hospedeiro , Cadeias beta de Integrinas , Neuropilina-1 , Linfócitos T Reguladores , Animais , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Linfócitos T Reguladores/imunologia , Camundongos , Neuropilina-1/metabolismo , Neuropilina-1/genética , Cadeias beta de Integrinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Condicionamento Pré-Transplante/métodos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Camundongos Endogâmicos C57BL , Gastroenteropatias/imunologia , Camundongos Endogâmicos BALB C , Receptores OX40/metabolismo , Doença Aguda , Transplante de Células-Tronco Hematopoéticas , Feminino , Ligante OX40RESUMO
Acute graft-versus-host disease (GVHD) is a frequent and potentially life-threatening complication following allogeneic hematopoietic cell transplantation (HCT). Mesenchymal stromal cells (MSCs), rare precursors found in all body tissues, possess immunosuppressive properties and can inhibit alloreactivity both in vitro and in vivo. Two decades ago, we introduced bone marrow-derived (BM) MSCs as a novel therapy for acute GVHD. While some patients responded to BM-MSCs, the response was not universal. Commercially available BM-MSCs are now used for acute GVHD treatment in Canada, Japan, and New Zealand. The fetus is protected from the mother's immune system by the placenta, and our research found that placenta-derived decidua stromal cells (DSCs) offer a stronger immunosuppressive effect than other sources of stromal cells. Safety studies in rabbits, rats, mice, and humans have shown negligible or no side effects from BM-MSCs or DSCs. In a phase I/II trial for severe acute GVHD, we treated 21 patients (median age, 49 years; range 1.6-72 years) with severe biopsy-proven gastrointestinal acute GVHD. The median cell dose of DSCs was 1.2 × 106 (range 0.9-2.9) cells/kg body weight, with a median of 2 (range 1-6) infusions given 1 week apart. The cell viability of DSCs was 93% (range, 69%-100%), and the median cell passage number was 4 (range, 2-4). All patients responded, with a complete response of acute GVHD in 11 patients and partial response in 10 and 1-year survival of 81%. Randomized trials are needed to prove the superiority of DSCs compared to ruxolitinib and/or other novel immunosuppressive therapies.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Feminino , Humanos , Camundongos , Pessoa de Meia-Idade , Coelhos , Ratos , Doença Aguda , Decídua , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunossupressores , Células Estromais , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Idoso , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como AssuntoRESUMO
A 9-year-old boy with adrenoleukodystrophy due to ABCD1 whole-gene deletion was diagnosed with active cerebral adrenoleukodystrophy characterized by demyelination and gadolinium enhancement on brain MRI. He underwent hematopoietic cell transplant (HCT) with autologous CD34+ cells transduced with an ABCD1-expressing lentiviral vector (eli-cel [elivaldogene autotemcel]) as part of the ALD-104 clinical trial. Fifty days after HCT, the patient's MRI showed gadolinium resolution; the whole-blood vector copy number (VCN) was 0.666 copies/mL. Six months following HCT, an MRI showed re-emergence of gadolinium enhancement; the VCN had decreased to 0.029 copies/mL. Polyclonal antibodies to the ABCD1 gene product were detectable 9 months after transplant, showing reactivity to peroxisomes, suggesting an immune response; however, no antibody binding to human CD34+ cells could be shown. The patient underwent a successful allogeneic HCT 12 months after gene therapy with resultant gadolinium resolution, cerebral disease stabilization, and the disappearance of antibodies. The coincident VCN loss and appearance of antibody to the ABCD1 gene product is of interest, and we postulate that it is related to the patient's whole ABCD1 gene deletion. We suggest close monitoring of loss of gene therapy efficacy due to immune response in patients with full deletions who are considering gene therapy.
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Rationale: Acute lung injury (ALI) carries a high risk of mortality but has no established pharmacologic therapy. We previously found that experimental ALI occurs through natural killer (NK) cell NKG2D receptor activation and that the cognate human ligand, MICB, was associated with ALI after transplantation. Objectives: To investigate the association of a common missense variant, MICBG406A, with ALI. Methods: We assessed MICBG406A genotypes within two multicenter observational study cohorts at risk for ALI: primary graft dysfunction (N = 619) and acute respiratory distress syndrome (N = 1,376). Variant protein functional effects were determined in cultured and ex vivo human samples. Measurements and Main Results: Recipients of MICBG406A-homozygous allografts had an 11.1% absolute risk reduction (95% confidence interval [CI], 3.2-19.4%) for severe primary graft dysfunction after lung transplantation and reduced risk for allograft failure (hazard ratio, 0.36; 95% CI, 0.13-0.98). In participants with sepsis, we observed 39% reduced odds of moderately or severely impaired oxygenation among MICBG406A-homozygous individuals (95% CI, 0.43-0.86). BAL NK cells were less frequent and less mature in participants with MICBG406A. Expression of missense variant protein MICBD136N in cultured cells resulted in reduced surface MICB and reduced NKG2D ligation relative to wild-type MICB. Coculture of variant MICBD136N cells with NK cells resulted in less NKG2D activation and less susceptibility to NK cell killing relative to the wild-type cells. Conclusions: These data support a role for MICB signaling through the NKG2D receptor in mediating ALI, suggesting a novel therapeutic approach.
Assuntos
Lesão Pulmonar Aguda , Disfunção Primária do Enxerto , Humanos , Lesão Pulmonar Aguda/genética , Genômica , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismoRESUMO
RATIONALE: Allogeneic hematopoietic stem-cell transplantation (Allo-HSCT) recipients are still believed to be poor candidates for intensive care unit (ICU) management. OBJECTIVES AND METHODS: We investigated outcomes and determinants of mortality in a large multicenter retrospective cohort of Allo-HSCT patients admitted between January 1, 2015 and December 31, 2020 to 14 French ICUs. MEASUREMENTS AND MAIN RESULTS: One thousand one hundred and sixty-four patients were admitted throughout the study period. At the time of ICU admission, 765 (66%) patients presented multiple organ dysfunction, including acute respiratory failure in 40% (n=461). Median SOFA was 6 (4-8). Invasive mechanical ventilation, renal replacement therapy and vasopressors were required in 438 (38%), 221 (19%) and 468 (41%) patients respectively. ICU mortality was 26% (302 deaths). Day-90, 1-year and 3-year mortality rates were 48%, 63%, and 70%, respectively. By multivariable analysis, age >56 years (OR 2·0 [1·53-2·60], p<0·001), time from Allo-HSCT to ICU admission between 30 and 90 days (OR 1·68 [1·17-2·40], p=0·005), corticosteroid-refractory acute graft-versus-host disease (OR 1·63 [1·38-1·93], p<0·001), need for vasopressors (OR 1·9 [1·42-2·55], p<0·001), and mechanical ventilation (OR 3·1 [2·29-4·18], p<0·001) were independently associated with day-90 mortality. In patients requiring mechanical ventilation, mortality rates ranged from 39% (no other risk factors for mortality) to 100% (4 associated risk factors for mortality). CONCLUSIONS: Most critically ill Allo-HSCT recipients survive their ICU stay, including those requiring mechanical ventilation, with an overall day-90 survival rate reaching 51.8%. A careful assessment of goals of care is required in patients with ≥ 2 risk factors for mortality.
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Rationale: Plasma cell-free DNA levels correlate with disease severity in many conditions. Pretransplant cell-free DNA may risk stratify lung transplant candidates for post-transplant complications. Objectives: To evaluate if pretransplant cell-free DNA levels and tissue sources identify patients at high risk of primary graft dysfunction and other pre- and post-transplant outcomes. Methods: This multicenter, prospective cohort study recruited 186 lung transplant candidates. Pretransplant plasma samples were collected to measure cell-free DNA. Bisulfite sequencing was performed to identify the tissue sources of cell-free DNA. Multivariable regression models determined the association between cell-free DNA levels and the primary outcome of primary graft dysfunction and other transplant outcomes, including Lung Allocation Score, chronic lung allograft dysfunction, and death. Measurements and Main Results: Transplant candidates had twofold greater cell-free DNA levels than healthy control patients (median [interquartile range], 23.7 ng/ml [15.1-35.6] vs. 12.9 ng/ml [9.9-18.4]; P < 0.0001), primarily originating from inflammatory innate immune cells. Cell-free DNA levels and tissue sources differed by native lung disease category and correlated with the Lung Allocation Score (P < 0.001). High pretransplant cell-free DNA increased the risk of primary graft dysfunction (odds ratio, 1.60; 95% confidence interval [CI], 1.09-2.46; P = 0.0220), and death (hazard ratio, 1.43; 95% CI, 1.07-1.92; P = 0.0171) but not chronic lung allograft dysfunction (hazard ratio, 1.37; 95% CI, 0.97-1.94; P = 0.0767). Conclusions: Lung transplant candidates demonstrate a heightened degree of tissue injury with elevated cell-free DNA, primarily originating from innate immune cells. Pretransplant plasma cell-free DNA levels predict post-transplant complications.
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Ácidos Nucleicos Livres , Transplante de Pulmão , Disfunção Primária do Enxerto , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Gravidade do PacienteRESUMO
Signaling through colony-stimulating factor 1 receptor (CSF1R) regulates the development, differentiation, and activation of mononuclear phagocytic cells. Inhibition of this pathway provides an opportunity for therapeutic intervention in diseases in which these cells play a pathogenic role, including cancers, inflammation, fibrosis, and others. Multiple monoclonal antibodies and small molecule inhibitors targeting CSF1R or its known ligands CSF1 and IL-34 have been clinically tested and are generally well tolerated with side effects associated with on-target macrophage inhibition or depletion. To date, clinical activity of CSF1R inhibitors has been primarily observed in diffuse-type tenosynovial giant cell tumors, a disease characterized by genetic alterations in CSF1 leading to dysregulated CSF1R signaling. Expanded development into novel indications such as chronic graft vs host disease may provide new opportunities to further explore areas where a role for CSF1R dependent monocytes and macrophages has been established. This review presents key findings from the clinical development of 12 CSF1/CSF1R targeted therapies as monotherapy or in combination with immune checkpoint inhibitors and chemotherapy.
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Fator Estimulador de Colônias de Macrófagos , Neoplasias , Diferenciação Celular , Humanos , Fator Estimulador de Colônias de Macrófagos/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos , Monócitos , Neoplasias/tratamento farmacológicoRESUMO
Allogeneic hematopoietic cell transplantation (HCT) provides effective treatment for hematologic malignancies and immune disorders. Monitoring of posttransplant complications is critical, yet current diagnostic options are limited. Here, we show that cell-free DNA (cfDNA) in blood is a versatile analyte for monitoring of the most important complications that occur after HCT: graft-versus-host disease (GVHD), a frequent immune complication of HCT, infection, relapse of underlying disease, and graft failure. We demonstrate that these therapeutic complications are informed from a single assay, low-coverage bisulfite sequencing of cfDNA, followed by disease-specific bioinformatic analyses. To inform GVHD, we profile cfDNA methylation marks to trace the cfDNA tissues-of-origin and to quantify tissue-specific injury. To inform infection, we implement metagenomic cfDNA profiling. To inform cancer relapse, we implement analyses of tumor-specific genomic aberrations. Finally, to detect graft failure, we quantify the proportion of donor- and recipient-specific cfDNA. We applied this assay to 170 plasma samples collected from 27 HCT recipients at predetermined timepoints before and after allogeneic HCT. We found that the abundance of solid-organ-derived cfDNA in the blood at 1 mo after HCT is predictive of acute GVHD (area under the curve, 0.88). Metagenomic profiling of cfDNA revealed the frequent occurrence of viral reactivation in this patient population. The fraction of donor-specific cfDNA was indicative of relapse and remission, and the fraction of tumor-specific cfDNA was informative of cancer relapse. This proof-of-principle study shows that cfDNA has the potential to improve the care of allogeneic HCT recipients by enabling earlier detection and better prediction of the complex array of complications that occur after HCT.
Assuntos
Ácidos Nucleicos Livres , Impressões Digitais de DNA , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Biomarcadores , Metilação de DNA , Progressão da Doença , Doença Enxerto-Hospedeiro/sangue , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Biópsia Líquida/métodos , Especificidade de Órgãos/genética , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Recidiva , Transplante HomólogoRESUMO
Multivessel coronary artery disease is present in â¼50% of patients with acute coronary syndrome and, compared with single-vessel disease, entails a higher risk of new ischaemic events and a worse prognosis. Randomized controlled trials have shown the superiority of 'complete revascularization' over culprit lesion-only treatment. Trials, however, only included patients treated with percutaneous coronary intervention (PCI), and evidence regarding complete revascularization with coronary artery bypass graft (CABG) surgery after culprit lesion-only PCI ('hybrid revascularization') is lacking. The CABG after PCI is an open, non-negligible therapeutic option, for patients with non-culprit left main and/or left anterior descending coronary artery disease where evidence in chronic coronary syndrome patients points in several cases to a preference of CABG over PCI. This valuable but poorly studied 'PCI first-CABG later' option presents, however, relevant challenges, mostly in the need of interrupting post-stenting dual antiplatelet therapy (DAPT) for surgery to prevent excess bleeding. Depending on patients' clinical characteristics and coronary anatomical features, either deferring surgery after a safe interruption of DAPT or bridging DAPT interruption with intravenous short-acting antithrombotic agents appears to be a suitable option. Off-pump minimally invasive surgical revascularization, associated with less operative bleeding than open-chest surgery, may be an adjunctive strategy when revascularization cannot be safely deferred and DAPT is not interrupted. Here, the rationale, patient selection, optimal timing, and adjunctive strategies are reviewed for an ideal approach to hybrid revascularization in post-acute coronary syndrome patients to support physicians' choices in a case-by-case patient-tailored approach.