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CRELD1 is a pivotal factor for heart development, the function of which is unknown in adult life. We here provide evidence that CRELD1 is an important gatekeeper of immune system homeostasis. Exploiting expression variance in large human cohorts contrasting individuals with the lowest and highest CRELD1 expression levels revealed strong phenotypic, functional and transcriptional differences, including reduced CD4+ T cell numbers. These findings were validated in T cell-specific Creld1-deficient mice. Loss of Creld1 was associated with simultaneous overactivation and increased apoptosis, resulting in a net loss of T cells with age. Creld1 was transcriptionally and functionally linked to Wnt signaling. Collectively, gene expression variance in large human cohorts combined with murine genetic models, transcriptomics and functional testing defines CRELD1 as an important modulator of immune homeostasis.
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Moléculas de Adesão Celular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Homeostase , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Imunomodulação , Animais , Moléculas de Adesão Celular/genética , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Proteínas da Matriz Extracelular/genética , Expressão Gênica , Técnicas de Inativação de Genes , Homeostase/imunologia , Humanos , Imunossenescência , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Camundongos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Via de Sinalização WntRESUMO
Human in vitro generated monocyte-derived dendritic cells (moDCs) and macrophages are used clinically, e.g., to induce immunity against cancer. However, their physiological counterparts, ontogeny, transcriptional regulation, and heterogeneity remains largely unknown, hampering their clinical use. High-dimensional techniques were used to elucidate transcriptional, phenotypic, and functional differences between human in vivo and in vitro generated mononuclear phagocytes to facilitate their full potential in the clinic. We demonstrate that monocytes differentiated by macrophage colony-stimulating factor (M-CSF) or granulocyte macrophage colony-stimulating factor (GM-CSF) resembled in vivo inflammatory macrophages, while moDCs resembled in vivo inflammatory DCs. Moreover, differentiated monocytes presented with profound transcriptomic, phenotypic, and functional differences. Monocytes integrated GM-CSF and IL-4 stimulation combinatorically and temporally, resulting in a mode- and time-dependent differentiation relying on NCOR2. Finally, moDCs are phenotypically heterogeneous and therefore necessitate the use of high-dimensional phenotyping to open new possibilities for better clinical tailoring of these cellular therapies.
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Células Dendríticas/imunologia , Interleucina-4/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Correpressor 2 de Receptor Nuclear/imunologia , Transdução de Sinais/imunologia , Diferenciação Celular , Linhagem da Célula , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Imunofenotipagem , Interleucina-4/genética , Interleucina-4/farmacologia , Ativação de Macrófagos , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Correpressor 2 de Receptor Nuclear/genética , Cultura Primária de Células , Fatores de Tempo , Transcrição GênicaRESUMO
BACKGROUND & AIMS: After pediatric liver transplantation (pLT), children undergo life-long immunosuppression since reliable biomarkers for the assessment of rejection probability are scarce. In the multicenter (n = 7) prospective clinical cohort "ChilSFree" study, we aimed to characterize longitudinal dynamics of soluble and cellular immune mediators during the first year after pLT and identify early biomarkers associated with outcome. METHODS: Using a Luminex-based multiplex technique paired with flow cytometry, we characterized longitudinal dynamics of soluble immune mediators (SIMs, n = 50) and immune cells in the blood of 244 patients at eight visits over 1 year: before, and 7/14/21/28 days and 3/6/12 months after pLT. RESULTS: The unsupervised clustering of patients based on SIM profiles revealed six unique SIM signatures associated with clinical outcome. From three signatures linked to improved outcome, one was associated with 1-year-long rejection-free survival and stable graft function and was characterized by low levels of pro-inflammatory SIMs (CXCL8/9/10/12, CCL7, SCGF-ß, sICAM-1), and high levels of regenerative (SCF, TNF-ß) and pro-apoptotic (TRAIL) SIMs (all, p <0.001, fold change >100). Of note, this SIM signature appeared 2 weeks after pLT and remained stable over the entire year, pointing towards its potential as a novel early biomarker for minimizing or weaning immunosuppression. In the blood of these patients, a higher frequency of CD56bright natural killer cells (p <0.01), a known hallmark also associated with operationally tolerant pLT patients, was detected. The concordance of the model for prediction of rejection based on identified SIM signatures was 0.715, and 0.795, in combination with living-related transplantation as a covariate, respectively. CONCLUSIONS: SIM blood signatures may enable the non-invasive and early assessment of rejection risks in the first year after pLT, paving the way for improved clinical management. IMPACT AND IMPLICATIONS: ChilSFree represents the largest pediatric liver transplant (pLT) cohort with paired longitudinal data on soluble immune mediators (SIMs) and immune phenotyping in the first year after pLT. SIM signatures allow for the selection of rejection-free patients 2 weeks after pLT independently of patient diagnosis, sex, or age. The SIM signatures may enable the non-invasive and early assessment of rejection risks, paving the way for minimization or withdrawal of immunosuppression after pLT.
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Early kinetics of lymphocyte subsets involved in tolerance and rejection following heart transplantation (HTx) are barely defined. Here, we aimed to delineate the early alloimmune response immediately after HTx. Therefore, blood samples from 23 heart-transplanted patients were collected before (pre-), immediately (T0), 24 hours (T24), and 3 weeks (3 wks) after HTx. Immunophenotyping was performed using flow cytometry. A significant increase was detected for terminally differentiated (TEMRA) CD4+ or CD8+ T cells and CD56dim CD16+ NK cells immediately after HTx linked to a decrease in naïve CD8+ and CM CD4+ T as well as CD56bright CD16- NK cells, returning to baseline levels at T24. More detailed analyses revealed increased CD69+ CD25- and diminished CD69- CD25- CD4+ or CD8+ T-cell proportions at T0 associated with decreasing S1PR1 expression. Passenger T and NK cells were found at low frequencies only in several patients at T0 and did not correlate with lymphocyte alterations. Collectively, these results suggest an immediate, transient shift toward memory T and NK cells following HTx. Opposite migratory properties of naïve versus memory T and NK cells occurring in the early phase after HTx could underlie these observations and may impinge on the development of allo-specific immune responses.
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Linfócitos T CD8-Positivos , Transplante de Coração , Humanos , Células Matadoras Naturais , Subpopulações de Linfócitos , Imunofenotipagem , Antígeno CD56/metabolismoRESUMO
Steroid-free immunosuppression protocols gained popularity in pediatric liver transplantation (pLT) after the introduction of IL-2-receptor blockade for induction therapy. We analyzed the clinical and immunologic outcome data of the multicenter prospective observational ChilSFree study to compare the impact of steroid-free versus steroid-containing immunosuppressive therapy following pLT in a real-life scenario. Two hundred forty-six children [55.3% male, age at pLT median: 2.4 (range: 0.2-17.9) y] transplanted for biliary atresia (43%), metabolic liver disease (9%), acute liver failure (4%), hepatoblastoma (9%), and other chronic end-stage liver diseases (39%) underwent immune monitoring and clinical data documentation over the first year after pLT. Patient and graft survival at 1 year was 98.0% and 92.7%, respectively. Primary immunosuppression was basiliximab induction followed by tacrolimus (Tac) monotherapy (55%), Tac plus steroid tapering over 3 months (29%), or cyclosporine and steroid tapering (7%). One center used intraoperative steroids instead of basiliximab followed by Tac plus mycophenolate mofetil (7% of patients). N = 124 biopsy-proven T-cell-mediated rejections were documented in n = 82 (33.3%) patients. T-cell-mediated rejection occurred early (median: 41 d, range: 3-366 d) after pLT. Patients initially treated with Tac plus steroids experienced significantly fewer episodes of rejection than patients treated with Tac alone (chi-square p <0.01). The use of steroids was associated with earlier downregulation of proinflammatory cytokines interferon (IFN)-γ, Interleukin (IL)-6, CX motif chemokin ligand (CXCL)8, IL-7, and IL-12p70. Both primary immunosuppression with Tac plus steroids and living donor liver transplantation were independent predictors of rejection-free survival 1 year after pLT on logistic regression analysis. Adjunctive steroid therapy after pLT leads to earlier suppression of the post-pLT proinflammatory response and significantly reduced rejection rates during the first year after pLT (15.9%). Fifty-one percent of patients initially treated without steroids remain steroid-free over the first 12 months without rejection.
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Imunossupressores , Transplante de Fígado , Humanos , Masculino , Criança , Feminino , Imunossupressores/efeitos adversos , Basiliximab , Transplante de Fígado/efeitos adversos , Doadores Vivos , Tacrolimo/uso terapêutico , Esteroides/uso terapêutico , Ácido Micofenólico/uso terapêutico , Sobrevivência de Enxerto , Rejeição de EnxertoRESUMO
Excessive inflammation is a major cause of morbidity and mortality in many viral infections including influenza. Therefore, there is a need for therapeutic interventions that dampen and redirect inflammatory responses and, ideally, exert antiviral effects. Itaconate is an immunomodulatory metabolite which also reprograms cell metabolism and inflammatory responses when applied exogenously. We evaluated effects of endogenous itaconate and exogenous application of itaconate and its variants dimethyl- and 4-octyl-itaconate (DI, 4OI) on host responses to influenza A virus (IAV). Infection induced expression of ACOD1, the enzyme catalyzing itaconate synthesis, in monocytes and macrophages, which correlated with viral replication and was abrogated by DI and 4OI treatment. In IAV-infected mice, pulmonary inflammation and weight loss were greater in Acod1-/- than in wild-type mice, and DI treatment reduced pulmonary inflammation and mortality. The compounds reversed infection-triggered interferon responses and modulated inflammation in human cells supporting non-productive and productive infection, in peripheral blood mononuclear cells, and in human lung tissue. All three itaconates reduced ROS levels and STAT1 phosphorylation, whereas AKT phosphorylation was reduced by 4OI and DI but increased by itaconate. Single-cell RNA sequencing identified monocytes as the main target of infection and the exclusive source of ACOD1 mRNA in peripheral blood. DI treatment silenced IFN-responses predominantly in monocytes, but also in lymphocytes and natural killer cells. Ectopic synthesis of itaconate in A549 cells, which do not physiologically express ACOD1, reduced infection-driven inflammation, and DI reduced IAV- and IFNγ-induced CXCL10 expression in murine macrophages independent of the presence of endogenous ACOD1. The compounds differed greatly in their effects on cellular gene homeostasis and released cytokines/chemokines, but all three markedly reduced release of the pro-inflammatory chemokines CXCL10 (IP-10) and CCL2 (MCP-1). Viral replication did not increase under treatment despite the dramatically repressed IFN responses. In fact, 4OI strongly inhibited viral transcription in peripheral blood mononuclear cells, and the compounds reduced viral titers (4OI>Ita>DI) in A549 cells whereas viral transcription was unaffected. Taken together, these results reveal itaconates as immunomodulatory and antiviral interventions for influenza virus infection.
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Vírus da Influenza A/imunologia , Macrófagos/imunologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Succinatos/farmacologia , Células A549 , Animais , Carboxiliases/deficiência , Carboxiliases/imunologia , Citocinas/genética , Citocinas/imunologia , Humanos , Macrófagos/virologia , Camundongos , Camundongos Knockout , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Células THP-1RESUMO
[This corrects the article DOI: 10.1371/journal.ppat.1010219.].
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BACKGROUND: Sudden infant death syndrome (SIDS) has been considered to be triggered by a combination of underlying immune dysregulation and infections. The thymus is a crucial lymphatic organ responsible for T cell development in infancy. We hypothesized that an altered thymic immune status may be detectable by intrathymic cytokine profiling in SIDS. METHODS: 27 cytokines in protein lysates of thymus tissue and thymus weights were assessed in 26 SIDS cases and 16 infants who died of other reasons. RESULTS: Seventeen out of 27 cytokines were increased in thymic tissue of SIDS compared to controls without infections, and the most significant discrepancy was in infants younger than 20 weeks. The thymic cytokine profiles in SIDS cases were similar to those in controls with severe infection; however, the magnitude of the cytokine concentration elevation in SIDS was less pronounced, indicating sub-clinical infections in SIDS. In contrast to SIDS, intrathymic cytokine concentrations and thymus weight were increased with age in control children. CONCLUSIONS: Elevated thymic cytokine expression and thymus weight, as well as impaired age-related alterations in SIDS, may be influenced by subclinical infection, which may play a role in initiating SIDS in infants with a compromised immune response. IMPACT STATEMENT: Increased thymic weight and cytokine concentration may suggest possible subclinical infection in SIDS. Elevated thymic weight and cytokine concentration mainly in SIDS cases aged <20 weeks. Age-related impairment in the thymic weight and cytokine expression may be impaired by subclinical infection in SIDS.
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Citocinas , Morte Súbita do Lactente , Lactente , Criança , Humanos , Citocinas/metabolismo , Infecções Assintomáticas , TimoRESUMO
PURPOSE: Post-acute sequelae of COVID-19 (PASC) affect approximately 10% of convalescent patients. The spectrum of symptoms is broad and heterogeneous with fatigue being the most often reported sequela. Easily accessible blood biomarkers to determine PASC severity are lacking. Thus, our study aimed to correlate immune phenotypes with PASC across the severity spectrum of COVID-19. METHODS: A total of 176 originally immunonaïve, convalescent COVID-19 patients from a prospective cohort during the first pandemic phase were stratified by initial disease severity and underwent clinical, psychosocial, and immune phenotyping around 10 weeks after first COVID-19 symptoms. COVID-19-associated fatigue dynamics were assessed and related to clinical and immune phenotypes. RESULTS: Fatigue and severe fatigue were commonly reported irrespective of initial COVID-19 severity or organ-specific PASC. A clinically relevant increase in fatigue severity after COVID-19 was detected in all groups. Neutralizing antibody titers were higher in patients with severe acute disease, but no association was found between antibody titers and PASC. While absolute peripheral blood immune cell counts in originally immunonaïve PASC patients did not differ from unexposed controls, peripheral CD3+CD4+ T cell counts were independently correlated with fatigue severity across all strata in multivariable analysis. CONCLUSIONS: Patients were at similar risk of self-reported PASC irrespective of initial disease severity. The independent correlation between fatigue severity and blood T cell phenotypes indicates a possible role of CD4+ T cells in the pathogenesis of post-COVID-19 fatigue, which might serve as a blood biomarker.
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COVID-19 , Linfócitos T , Humanos , Síndrome de COVID-19 Pós-Aguda , COVID-19/complicações , Estudos Prospectivos , Fenótipo , Progressão da Doença , Fadiga/etiologiaRESUMO
Inflammation including immunothrombosis by neutrophil extracellular traps (NETs) has important implications in acute ischemic stroke and can affect reperfusion status, susceptibility to stroke associated infections (SAI) as well as functional clinical outcome. NETs were shown to be prevalent in stroke thrombi and NET associated markers were found in stroke patients' blood. However, little is known whether blood derived NET markers reflect the amount of NETs in thrombi. Conclusions from blood derived markers to thrombus composition might open avenues for novel strategies in diagnostic and therapeutic approaches. We prospectively recruited 166 patients with acute ischemic stroke undergoing mechanical thrombectomy between March 2018 and May 2021. Available thrombi (n = 106) were stained for NET markers DNA-histone-1 complexes and myeloperoxidase (MPO). Cell free DNA (cfDNA), deoxyribonuclease (DNase) activity, MPO-histone complexes and a cytokine-panel were measured before thrombectomy and after seven days. Clinical data, including stroke etiology, reperfusion status, SAI and functional outcome after rehabilitation, were collected of all patients. NET markers were present in all thrombi. At onset the median concentration of cfDNA in blood was 0.19 µg/ml increasing to 0.30 µg/ml at 7 days. Median DNase activity at onset was 4.33 pmol/min/ml increasing to 4.96 pmol/min/ml at 7 days. Within thrombi DNA-histone-1 complexes and MPO correlated with each other (ρ = 0.792; p < 0.001). Moreover, our study provides evidence for an association between the amount of NETs and endogenous DNase activity in blood with amounts of NETs in cerebral thrombi. However, these associations need to be confirmed in larger cohorts, to investigate the potential clinical implications for individualized therapeutic and diagnostic approaches in acute ischemic stroke.
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Biomarcadores , Armadilhas Extracelulares , AVC Isquêmico , Humanos , Armadilhas Extracelulares/metabolismo , Biomarcadores/sangue , Masculino , Feminino , Idoso , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , Pessoa de Meia-Idade , Estudos Prospectivos , Peroxidase/sangue , Idoso de 80 Anos ou mais , Ácidos Nucleicos Livres/sangue , Trombectomia , Trombose/sangue , Trombose/diagnóstico , Neutrófilos/metabolismoRESUMO
Pretransplant allosensitization to human leukocyte antigens (HLA) increases the recipient's waiting list time and mortality in lung transplantation. Rather than waiting for crossmatch-negative donors, since 2013, recipients with preformed donor-specific antiHLA antibodies (pfDSA) have been managed with repeated IgA- and IgM-enriched intravenous immunoglobulin (IgGAM) infusions, usually in combination with plasmapheresis before IgGAM and a single dose of antiCD20 antibody. This retrospective study presents our 9-year experience with patients transplanted with pfDSA. Records of patients transplanted between February 2013 and May 2022 were reviewed. Outcomes were compared between patients with pfDSA and those without any de novo donor-specific antiHLA antibodies. The median follow-up time was 50 months. Of the 1,043 patients who had undergone lung transplantation, 758 (72.7%) did not develop any early donor-specific antiHLA antibodies, and 62 (5.9%) patients exhibited pfDSA. Among the 52 (84%) patients who completed treatment, pfDSA was cleared in 38 (73%). In pfDSA vs control patients and at 8-year follow-up, respectively, graft survival (%) was 75 vs 65 (P = .493) and freedom from chronic lung allograft dysfunction (%) was 63 vs 65 (P = .525). In lung transplantation, crossing the preformed HLA-antibody barrier is safe using a treatment protocol based on IgGAM. Patients with pfDSA have a good 8-year graft survival rate and freedom from chronic lung allograft dysfunction, similar to control patients.
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Anticorpos , Transplante de Pulmão , Humanos , Estudos Retrospectivos , Doadores de Tecidos , Antígenos HLA , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Teste de HistocompatibilidadeRESUMO
BACKGROUND: For sudden infant death syndrome (SIDS), an impaired immunocompetence has been discussed for a long time. Cytokines and chemokines are soluble immune mediators (SIM) whose balance is essential for the immune status. We hypothesized that an imbalanced immune response might contribute to the etiology of SIDS. METHODS: We investigated 27 cytokines, chemokines, and growth factors in protein lysates of lungs derived from 29 SIDS cases and 15 control children deceased for other reasons. RESULTS: Except for the CCL5, no significant differences were detected in the lungs between SIDS cases with and without mild upper respiratory tract infections. In contrast, IL-1RA, IL-7, IL-13, and G-CSF were decreased in the merged SIDS cases compared to control cases without evidence of infection. Plotting SIM concentrations against infant age resulted in increasing concentrations in control but not in SIDS lungs, indicating a disturbed immune maturation. Moreover, an age-dependent shift towards a Th2-related pattern was observed in SIDS. CONCLUSIONS: Our findings suggest that an impaired maturation of the immune system, an insufficient response to respiratory pathogens, and an immune response modulated by Th1/Th2 imbalance might play a possible role in triggering SIDS. These findings might in part be explained by chronic stress. IMPACT: Maturation of the cytokine and chemokine network may be impaired in SIDS. An imbalance between Th1- and Th2-related cytokines, which may reflect a state of chronic stress causing a more Th2 shift. An impaired immune maturation, an insufficient response to respiratory pathogens, and an immune response modulated by Th1/Th2 imbalance might play a possible role in SIDS.
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Infecções Respiratórias , Morte Súbita do Lactente , Lactente , Criança , Humanos , Citocinas/metabolismo , Morte Súbita do Lactente/etiologia , Quimiocinas , Pulmão/metabolismoRESUMO
BACKGROUND: Cell-free DNA (cfDNA) and endogenous deoxyribonuclease activity are opposing mediators and might influence the inflammatory response following acute ischemic stroke. In this cohort study, we investigated the relation between these markers, circulating inflammatory mediators and clinical course including occurrence of stroke-associated infections (SAI) in patients with acute stroke. METHODS: Ninety-two patients with stroke due to large vessel occlusion undergoing mechanical thrombectomy were prospectively recruited at Hannover Medical School from March 2018 to August 2019. Deoxyribonuclease activity, cfDNA, damage-associated molecular patterns, and circulating cytokines were measured in venous blood collected immediately before mechanical thrombectomy and 7 days later. Reperfusion status was categorized (sufficient/insufficient). Clinical outcome was evaluated using the modified Rankin Scale after 90 days, where a score of 3 to 6 was considered unfavorable. To validate findings regarding SAI, another stroke cohort (n=92) was considered with blood taken within 24 hours after stroke onset. RESULTS: Patients with unfavorable clinical outcome had higher cfDNA concentrations. After adjustment for confounders (Essen Stroke Risk Score, National Institutes of Health Stroke Scale, and sex), 7-day cfDNA was independently associated with clinical outcome and especially mortality (adjusted odds ratio: 3.485 [95% CI, 1.001-12.134] and adjusted odds ratio: 9.585 [95% CI, 2.006-45.790]). No association was found between reperfusion status and cfDNA or deoxyribonuclease activity. While cfDNA concentrations correlated positively, deoxyribonuclease activity inversely correlated with distinct biomarkers. Baseline deoxyribonuclease activity was lower in patients who developed SAI compared with patients without SAI. This association was confirmed after adjustment for confounding factors (adjusted odds ratio: 0.447 [95% CI, 0.237-0.844]). In cohort 2, differences of deoxyribonuclease activity between patients with and without SAI tended to be higher with higher stroke severity. CONCLUSIONS: The interplay of endogenous deoxyribonuclease activity and cfDNA in acute stroke entails interesting novel diagnostic and potential therapeutic approaches. We confirm an independent association of cfDNA with a detrimental clinical course after stroke due to large vessel occlusion. This study provides first evidence for lower endogenous deoxyribonuclease activity as risk factor for SAI after severe stroke.
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Isquemia Encefálica , Ácidos Nucleicos Livres , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/terapia , Estudos de Coortes , Desoxirribonucleases , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia , Trombectomia/efeitos adversos , Resultado do TratamentoRESUMO
Lung carcinoid tumors, also referred to as pulmonary neuroendocrine tumors or lung carcinoids, are rare neoplasms of the lung with a more favorable prognosis than other subtypes of lung cancer. Still, some patients suffer from relapsed disease and metastatic spread. Several recent single-cell studies have provided detailed insights into the cellular heterogeneity of more common lung cancers, such as adeno- and squamous cell carcinoma. However, the characteristics of lung carcinoids on the single-cell level are yet completely unknown. To study the cellular composition and single-cell gene expression profiles in lung carcinoids, we applied single-cell RNA sequencing to three lung carcinoid tumor samples and normal lung tissue. The single-cell transcriptomes of carcinoid tumor cells reflected intertumoral heterogeneity associated with clinicopathological features, such as tumor necrosis and proliferation index. The immune microenvironment was specifically enriched in noninflammatory monocyte-derived myeloid cells. Tumor-associated endothelial cells were characterized by distinct gene expression profiles. A spectrum of vascular smooth muscle cells and pericytes predominated the stromal microenvironment. We found a small proportion of myofibroblasts exhibiting features reminiscent of cancer-associated fibroblasts. Stromal and immune cells exhibited potential paracrine interactions which may shape the microenvironment via NOTCH, VEGF, TGFß and JAK/STAT signaling. Moreover, single-cell gene signatures of pericytes and myofibroblasts demonstrated prognostic value in bulk gene expression data. Here, we provide first comprehensive insights into the cellular composition and single-cell gene expression profiles in lung carcinoids, demonstrating the noninflammatory and vessel-rich nature of their tumor microenvironment, and outlining relevant intercellular interactions which could serve as future therapeutic targets.
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Tumor Carcinoide , Carcinoma Neuroendócrino , Neoplasias Pulmonares , Tumores Neuroendócrinos , Tumor Carcinoide/genética , Tumor Carcinoide/metabolismo , Tumor Carcinoide/patologia , Carcinoma Neuroendócrino/patologia , Células Endoteliais/metabolismo , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/patologia , Prognóstico , Microambiente Tumoral/genéticaRESUMO
Heart transplantation across preformed donor-specific HLA-antibody barriers is associated with impaired short- and long-term survival. Therefore, in recipients with preformed anti-HLA antibodies, waiting for crossmatch-negative donors is standard practice. As an alternative strategy, recipients with preformed anti-HLA donor specific antibodies have been managed at our institutions with a perioperative desensitization regimen. A retrospective analysis was performed comparing heart transplant recipients with preformed donor-specific HLA-antibodies to recipients without donor-specific antibodies. Recipients with a positive virtual crossmatch received a perioperative desensitization protocol including tocilizumab intraoperatively, plasma exchange and rituximab followed by a six-month course of IgGAM. Among the 117 heart-transplanted patients, 19 (16%) patients underwent perioperative desensitization, and the remaining 98 (84%) patients did not. Cold ischemic time, posttransplant extracorporeal life support for primary graft dysfunction, and intensive care unit stay time did not differ between groups. At 1-year follow-up, freedom from pulsed steroid therapy for presumed rejection and biopsy-confirmed acute cellular or humoral rejection did not differ between groups. One-year survival amounted to 94.7% in the treated patients and 81.4% in the control group. Therefore, heart transplantation in sensitized recipients undergoing a perioperative desensitization appears safe with comparable postoperative outcomes as patients with a negative crossmatch.
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Transplante de Coração , Transplante de Rim , Anticorpos , Soro Antilinfocitário , Dessensibilização Imunológica/métodos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Antígenos HLA , Teste de Histocompatibilidade/métodos , Humanos , Transplante de Rim/efeitos adversos , Estudos RetrospectivosRESUMO
Foxp3+ Treg cells, which are crucial for maintenance of self-tolerance, mainly develop within the thymus, where they arise from CD25+ Foxp3- or CD25- Foxp3+ Treg cell precursors. Although it is known that infections can cause transient thymic involution, the impact of infection-induced thymus atrophy on thymic Treg (tTreg) cell development is unknown. Here, we infected mice with influenza A virus (IAV) and studied thymocyte population dynamics post infection. IAV infection caused a massive, but transient thymic involution, dominated by a loss of CD4+ CD8+ double-positive (DP) thymocytes, which was accompanied by a significant increase in the frequency of CD25+ Foxp3+ tTreg cells. Differential apoptosis susceptibility could be experimentally excluded as a reason for the relative tTreg cell increase, and mathematical modeling suggested that enhanced tTreg cell generation cannot explain the increased frequency of tTreg cells. Yet, an increased death of DP thymocytes and augmented exit of single-positive (SP) thymocytes was suggested to be causative. Interestingly, IAV-induced thymus atrophy resulted in a significantly reduced T-cell receptor (TCR) repertoire diversity of newly produced tTreg cells. Taken together, IAV-induced thymus atrophy is substantially altering the dynamics of major thymocyte populations, finally resulting in a relative increase of tTreg cells with an altered TCR repertoire.
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Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Linfócitos T Reguladores/imunologia , Timo/imunologia , Timo/patologia , Animais , Atrofia , Biomarcadores , Sobrevivência Celular/imunologia , Imunofenotipagem , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Camundongos , Infecções por Orthomyxoviridae/virologia , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Timócitos/imunologia , Timócitos/metabolismoRESUMO
Post-transplant cytomegalovirus (CMV) infections and increased viral replication are associated with CMV-specific T-cell anergy. In the ATHENA-study, de-novo everolimus (EVR) with reduced-exposure tacrolimus (TAC) or cyclosporine (CyA) showed significant benefit in preventing CMV infections in renal transplant recipients as compared to standard TAC + mycophenolic acid (MPA). However, immunomodulatory mechanisms for this effect remain largely unknown. Ninety patients from the ATHENA-study completing the 12-month visit on-treatment (EVR + TAC n = 28; EVR + CyA n = 19; MPA + TAC n = 43) were included in a posthoc analysis. Total lymphocyte subpopulations were quantified. CMV-specific CD4 T cells were determined after stimulation with CMV-antigen, and cytokine-profiles and various T-cell anergy markers were analyzed using flow cytometry. While 25.6% of MPA + TAC-treated patients had CMV-infections, no such events were reported in EVR-treated patients. Absolute numbers of lymphocyte subpopulations were comparable between arms, whereas the percentage of regulatory T cells was significantly higher with EVR + CyA versus MPA + TAC (p = 0.019). Despite similar percentages of CMV-specific T cells, their median expression of CTLA-4 and PD-1 was lower with EVR + TAC (p < 0.05 for both) or EVR + CyA (p = 0.045 for CTLA-4) compared with MPA + TAC. Moreover, mean percentages of multifunctional CMV-specific T cells were higher with EVR + TAC (27.2%) and EVR + CyA (29.4%) than with MPA + TAC (19.0%). In conclusion, EVR-treated patients retained CMV-specific T-cell functionality, which may contribute to enhanced protection against CMV infections.
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Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Everolimo/imunologia , Imunossupressores/imunologia , Transplante de Rim/métodos , Linfócitos T/imunologia , Adulto , Ciclosporina/imunologia , Ciclosporina/uso terapêutico , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Everolimo/uso terapêutico , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/imunologia , Ácido Micofenólico/uso terapêutico , Linfócitos T/metabolismo , Linfócitos T/virologia , Tacrolimo/imunologia , Tacrolimo/uso terapêutico , Resultado do TratamentoRESUMO
The third edition of Flow Cytometry Guidelines provides the key aspects to consider when performing flow cytometry experiments and includes comprehensive sections describing phenotypes and functional assays of all major human and murine immune cell subsets. Notably, the Guidelines contain helpful tables highlighting phenotypes and key differences between human and murine cells. Another useful feature of this edition is the flow cytometry analysis of clinical samples with examples of flow cytometry applications in the context of autoimmune diseases, cancers as well as acute and chronic infectious diseases. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid. All sections are written and peer-reviewed by leading flow cytometry experts and immunologists, making this edition an essential and state-of-the-art handbook for basic and clinical researchers.
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Doenças Autoimunes/imunologia , Citometria de Fluxo , Infecções/imunologia , Neoplasias/imunologia , Animais , Doença Crônica , Humanos , Camundongos , Guias de Prática Clínica como AssuntoRESUMO
BACKGROUND: Ischemia/reperfusion injury (IRI) is associated with inflammatory responses contributing to the development of primary graft dysfunction (PGD) and rejection. Here, we investigated the pathophysiology of IRI and the early phase after heart transplantation (HTx) regarding its cytokine/chemokine and endothelial networks. METHODS: Using multiplex technology, we assessed protein concentrations in plasma samples of HTx recipients (n = 11) pre-, postoperatively, 24 h and 3 weeks after HTx. The same proteins were quantified in organ storage solutions at the end of heart storage (n = 10). Unsupervised cluster, principal component analysis (PCA), K-nearest neighbor (KNN) network classifier analysis, ANOVA and Spearman correlation analyses were performed to identify specific patterns for IRI and individual kinetics of important soluble factors in HTx. RESULTS: Unique patterns of soluble factors were identified in plasma of HTx patients. KNN analysis defined IL-10, IL-6, sIL-6Rα, IL-1RA, IL-16, sVEGFR-1, IGFBP-1, HGF and sHer-2 as strongest signals directly post-Tx declining 24 hrs after HTx. By contrast, MIF, osteopontin (OPN), sVCAM-1 and sICAM-1, IGFBP-1, SCGF-ß, HGF were highly enriched in organ storage solutions, reflecting distinct ischemic (storage solution) vs. reperfusion (plasma) signatures. CONCLUSIONS: We identified specific inflammatory signatures for ischemic vs. reperfusion phases of HTx, associated with pro- as well as anti-inflammatory and endothelial biomarker candidates for IRI. These signatures might help to identify potential danger factors and their networks at both the ex situ (ischemic) as well as the reperfusion phase in the recipient after implantation.
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Biomarcadores/metabolismo , Isquemia/metabolismo , Traumatismo por Reperfusão/metabolismo , Adolescente , Adulto , Quimiocinas/metabolismo , Criança , Citocinas/metabolismo , Feminino , Transplante de Coração/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Reperfusão/métodos , Adulto JovemRESUMO
BACKGROUND: Immunocompromised people (ICP) and elderly individuals (older than 80 years) are at increased risk for severe coronavirus infections. To protect against serious infection with SARS-CoV-2, ICP are taking precautions that may include a reduction of social contacts and participation in activities which they normally enjoy. Furthermore, for these people, there is an uncertainty regarding the effectiveness of the vaccination. The COVID-19 Contact (CoCo) Immune study strives to characterize the immune response to COVID-19 vaccination in immunocompromised, elderly people, and patients with hematological or oncological diseases. The study uses blood-based screenings to monitor the humoral and cellular immune response in these groups after vaccination. Questionnaires and qualitative interviews are used to describe the level of social participation. METHODS: The CoCo Immune Study is a mixed methods prospective, longitudinal, observational study at two large university hospitals in Northern Germany. Starting in March 2021, it monitors anti-SARS-CoV-2 immune responses and collects information on social participation in more than 600 participants, at least 18 years old. Inclusion criteria and subcohorts: Participants with (1) regularly intake of immunosuppressive medication (ICP-cohort) or (2) age ≥ 80 years (80 + -cohort). Additionally, patients with current or former (3) myeloid, (4) lymphatic disease or (5) solid tumor under checkpoint inhibition (3-5: HO-cohort). EXCLUSION CRITERIA: (1) refusal to give informed consent, (2) contraindication to blood testing, (3) inability to declare consent. Participants complete a questionnaire at four different time points: prior to full vaccination, and 1, 6 and 12 months after completed vaccination. In addition, participants draw blood samples themselves or through a local health care provider and send them with their questionnaires per post at the respective time points after vaccination. Patients of the HO cohort dispense additional blood samples at week 3 to 12 and at month 6 to 9 after 2nd vaccination to gain additional knowledge in B and T cell responses. Selected participants are invited to qualitative interviews about social participation. DISCUSSION: This observational study is designed to gain insight into the immune response of people with weakened immune systems and to find out how social participation is affected after COVID-19 vaccination. TRIAL REGISTRATION: This study was registered with German Clinical Trial Registry (registration number: DRKS00023972) on 30th December 2020.