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1.
Dig Dis Sci ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127844

RESUMO

BACKGROUND: Breath testing for small intestinal bacterial overgrowth (SIBO) is typically performed using clinic-based equipment or single-use test kits. AIMS: This study aimed to evaluate the utility of a portable, point-of-care breath analysis device (AIRE®, FoodMarble) in patients suspected to have SIBO. A technical assessment including a comparison to existing mail-in kits was first performed. Then, postprandial breath hydrogen levels of patients before and after antibiotic treatment were gathered and compared to levels seen in a healthy cohort. METHODS: For the comparison, 50 patients suspected of having SIBO were provided with an AIRE device and performed concurrent LHBTs at-home with a mail-in breath test kit. For the postprandial analysis, twenty-four patients with chronic GI symptoms measured their postprandial hydrogen for 7 days prior to antibiotic treatment and for 7 days after treatment. 10 healthy controls also measured their postprandial hydrogen for 7 days. RESULTS: Substantial agreement was demonstrated between AIRE and the mail-in kits for the performance of lactulose hydrogen breath tests (κ = 0.8). Prior to treatment, patients had significantly greater daily postprandial hydrogen than healthy controls (p < 0.001). The mean postprandial hydrogen of patients reduced significantly after treatment (p < 0.001). CONCLUSIONS: Measuring postprandial hydrogen shows potential as a means of differentiating patients with chronic GI symptoms from healthy controls and may be useful in monitoring patients before, during, and after treatment. Future studies could help determine if pre-treatment breath gas levels are predictive of response to antibiotic treatment.

2.
Am J Med Genet A ; : e63841, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136524

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) affects 1 in 1000 adults. Most cases result from causative PKD1 or PKD2 variants. HNF1B, GANAB and ALG9 variants are also associated with ADPKD. Recent evidence indicates that monoallelic loss-of-function (LoF) IFT140 variants are a cause for non-syndromic ADPKD. We describe 368 patients with IFT140 LoF variants and a spectrum of phenotypic findings that support the association of IFT140 with PKD. We reviewed patients with an unknown cause for their cystic disease and those with heterozygous LoF IFT140 variants classified as pathogenic or likely pathogenic from a cohort that received genetic testing using a panel of 385 renal disease-associated genes. IFT140 LoF variants were significantly enriched in patients with cystic disease when compared with those without cystic disease. A cystic phenotype was reported in 223 of the 368 (60.6%) individuals harboring an IFT140 LoF variant, 98% of which had no other identified cause for their cystic disease. Of 122 unique LoF IFT140 variants identified, 56 (46%) were frameshift, 38 (31%) nonsense, 22 (18%) splice site and 6 (5%) exon-level deletions. Only six IFT140 individuals were reported with end-stage kidney disease, consistent with observed milder clinical presentations in IFT140-related PKD. This study offers further evidence for the involvement of LoF IFT140 variants in PKD, particularly when no additional molecular etiology has been identified.

3.
Nature ; 632(8023): 182-191, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39048822

RESUMO

CD4+ T cells can either enhance or inhibit tumour immunity. Although regulatory T cells have long been known to impede antitumour responses1-5, other CD4+ T cells have recently been implicated in inhibiting this response6,7. Yet, the nature and function of the latter remain unclear. Here, using vaccines containing MHC class I (MHC-I) neoantigens (neoAgs) and different doses of tumour-derived MHC-II neoAgs, we discovered that whereas the inclusion of vaccines with low doses of MHC-II-restricted peptides (LDVax) promoted tumour rejection, vaccines containing high doses of the same MHC-II neoAgs (HDVax) inhibited rejection. Characterization of the inhibitory cells induced by HDVax identified them as type 1 regulatory T (Tr1) cells expressing IL-10, granzyme B, perforin, CCL5 and LILRB4. Tumour-specific Tr1 cells suppressed tumour rejection induced by anti-PD1, LDVax or adoptively transferred tumour-specific effector T cells. Mechanistically, HDVax-induced Tr1 cells selectively killed MHC-II tumour antigen-presenting type 1 conventional dendritic cells (cDC1s), leading to low numbers of cDC1s in tumours. We then documented modalities to overcome this inhibition, specifically via anti-LILRB4 blockade, using a CD8-directed IL-2 mutein, or targeted loss of cDC2/monocytes. Collectively, these data show that cytotoxic Tr1 cells, which maintain peripheral tolerance, also inhibit antitumour responses and thereby function to impede immune control of cancer.


Assuntos
Antígenos de Neoplasias , Linfócitos T CD4-Positivos , Citotoxicidade Imunológica , Imunoterapia , Neoplasias , Linfócitos T Reguladores , Animais , Feminino , Humanos , Masculino , Camundongos , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular Tumoral , Quimiocina CCL5/metabolismo , Células Dendríticas/imunologia , Granzimas/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Interleucina-10/metabolismo , Interleucina-10/imunologia , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T Reguladores/imunologia , Receptores Imunológicos/antagonistas & inibidores , Glicoproteínas de Membrana/antagonistas & inibidores , Tolerância Imunológica , Linfócitos T CD8-Positivos/imunologia
4.
Am J Gastroenterol ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912927

RESUMO

INTRODUCTION: We examined autoimmunity markers (AIM) and autonomic dysfunction in patients with chronic neurogastroenterological symptoms and their relationship to joint hypermobility/hypermobility spectrum disorder (JH/HSD). METHODS: AIM positivity was defined as a diagnosis of known autoimmune/autoinflammatory disorder with at least 1 positive seromarker of autoimmunity or at least 2 positive seromarkers by themselves. Three cohorts were studied: (i) retrospective (n = 300), (ii) prospective validation cohort (n = 133), and (iii) treatment cohort (n = 40), administered open-label intravenous immunoglobulin (IVIG). RESULTS: AIM positivity was found in 40% and 29% of the retrospective and prospective cohorts, the majority of whom (71% and 69%, respectively) had autoinflammatory disorder. Significantly more patients with AIM had elevations of C-reactive protein (31% vs 15%, P < 0.001) along with an increased proportion of cardiovascular autonomic dysfunction (48% vs 29%; P < 0.001), small fiber neuropathy (20% vs 9%; P = 0.002), and HLADQ8 positivity (24% vs 13%, P = 0.01). Patients with JH/HSD were more likely to have AIM (43% vs 15%, P = 0.001) along with more severe autonomic and gastrointestinal (GI) symptom scores. IVIG treatment was associated with robust improvement in pain, GI, and autonomic symptoms, but adverse events were experienced by 62% of patients. DISCUSSION: Autoimmune markers and autonomic dysfunction are common in patients with unexplained GI symptoms, especially in those with JH/HSD. Many patients seem to respond to IVIG treatment, but this needs to be confirmed by controlled trials. These results highlight the need for vigilance for autoimmune and autonomic factors and JH/HSD in patients with neurogastroenterological disorders. Clinicaltrials.gov , NCT04859829.

5.
Acad Pediatr ; 24(7): 1141-1149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38719092

RESUMO

OBJECTIVE: The purpose of this study was to compare three models of pediatric physiatry care (in-person, hybrid, and all-virtual) in terms of parent experience and physician- and therapist-reported quality of care. We hypothesized that the all-virtual model would have lower parent experience scores and lower quality scores compared with the other two models of care. METHODS: We designed a convergent parallel mixed methods study incorporating a cluster-randomized crossover design. Quantitative data included surveys of parents, physicians, and therapists after visits to 13 medical therapy units in Northern California between January 2020 and January 2022. Qualitative data were collected in six focus groups with parents, physicians, and therapists. RESULTS: A total of 2455 visits were completed for 1281 unique children during the study period, including 507 in-person visits, 246 hybrid visits, and 1702 all-virtual visits. There were no differences in parent experience scores between the three models of care. Physicians and therapists rated all-virtual visits significantly lower in terms of quality of care, parent education, and physical exam, compared with the other two models of care, but qualitative results highlighted specific instances where all-virtual visits could be useful. CONCLUSIONS: Our findings suggest that parents, therapists, and physicians find a hybrid virtual model is an acceptable model of care that maintains the quality of care and facilitates parent education. All-virtual models may be appropriate for specific circumstances but are perceived as lower quality. Research exploring implementation of these models would be valuable for providing practical guidance in the future.


Assuntos
Pais , Qualidade da Assistência à Saúde , Humanos , Criança , Feminino , Masculino , Pediatria , Estudos Cross-Over , Pré-Escolar , Crianças com Deficiência , Telemedicina , Adolescente , Grupos Focais , Medicina Física e Reabilitação , California , Atitude do Pessoal de Saúde
6.
Animals (Basel) ; 14(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38612367

RESUMO

Precision Livestock Farming (PLF) involves the real-time monitoring of images, sounds, and other biological, physiological, and environmental parameters to assess and improve animal health and welfare within intensive and extensive production systems [...].

7.
Cureus ; 16(3): e57184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38681309

RESUMO

BACKGROUND: Data on median arcuate ligament syndrome (MALS) in children are scant. It is postulated that MALS can cause chronic abdominal pain. It is unclear what percentage of children with this condition are symptomatic and what comorbidities are associated with this syndrome. METHODS: In this retrospective study, data on consecutive patients in a single center diagnosed coincidentally with MALS during routine echocardiogram were reviewed. Symptom burden, comorbidities, and the effect of anthropometric indices on MALS were investigated. Descriptive statistics and nonparametric tests were used to describe the findings and to compare variables with normal distribution. RESULTS: Between 2013 and 2020, there were 82 children, 55 females (67%), mean age 13.9 ± 3.2 years, with MALS and complete record. Mean velocity across the stenotic area was 2.6 ± 0.4 m/s. Forty-six patients (57%) had abdominal pain. Age, gender, weight, body mass index (BMI), and Doppler velocity had no statistically significant influence on symptom occurrence. Conversely, patients with joint hypermobility and symptoms of orthostatic intolerance were more likely to have abdominal pain from MALS. Of 24 patients with joint hypermobility, 18 patients had abdominal pain (p=0.027). Thirty-eight patients with orthostatic intolerance (OI) with MALS complained of abdominal pain vs 13 patients with OI and no abdominal pain (p=<0.0001). CONCLUSION: Nearly half of patients with MALS had abdominal pain. Age, gender, weight, and the degree of stenosis had no statistically significant influence on symptom occurrence. OI, specifically postural orthostatic tachycardia syndrome (POTS), and joint hypermobility on exam predicted a higher propensity for abdominal pain in patients with MALS.

8.
J Telemed Telecare ; : 1357633X241238780, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38515372

RESUMO

BACKGROUND: Telehealth has the potential to increase access to care for medically underserved patients. This qualitative study aimed to identify telecare practices used during the COVID-19 pandemic to meet the needs of patients experiencing homelessness, patients with disabilities, and patients with language preference other than English (LOE). METHODS: We conducted a secondary qualitative data analysis of 47 clinician interviews at Federally Qualified Health Centers (FQHCs) around the country. Using thematic analysis, transcripts were coded by line-by-line by five qualitative researchers. A multidisciplinary team of telehealth experts, researchers and primary care clinicians reviewed memos and excerpts to generate major themes. RESULTS: We identified six main areas demonstrating how community providers developed strategies or practices to improve access to care for vulnerable patients: reaching patients experiencing homelessness, serving deaf and hard of hearing patients, improving access for patients with disabilities, serving patients with LOE, improving access for mental and behavioral health services, and educating patients about telehealth. During the pandemic, FQHCs developed innovative solutions to provide access to care for the unhoused, including using telehealth in shelters, vans, and distributing devices like mobile phones and tablets. Telehealth reduced transportation burdens for patients with disabilities and reduced no-show rates for mental health services by adapting group therapy via telehealth features (like break-out rooms) and increasing provider capacity. CONCLUSION: Our study identified strategies adopted by FQHCs to serve underserved populations during the COVID-19 pandemic. Our findings highlight the need for enduring strategies to improve health equity through telehealth..

9.
Sci Adv ; 10(9): eadh8493, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416825

RESUMO

N-MYC (encoded by MYCN) is a critical regulator of hematopoietic stem cell function. While the role of N-MYC deregulation is well established in neuroblastoma, the importance of N-MYC deregulation in leukemogenesis remains elusive. Here, we demonstrate that N-MYC is overexpressed in acute myeloid leukemia (AML) cells with chromosome inversion inv(16) and contributes to the survival and maintenance of inv(16) leukemia. We identified a previously unknown MYCN enhancer, active in multiple AML subtypes, essential for MYCN mRNA levels and survival in inv(16) AML cells. We also identified eukaryotic translation initiation factor 4 gamma 1 (eIF4G1) as a key N-MYC target that sustains leukemic survival in inv(16) AML cells. The oncogenic role of eIF4G1 in AML has not been reported before. Our results reveal a mechanism whereby N-MYC drives a leukemic transcriptional program and provides a rationale for the therapeutic targeting of the N-MYC/eIF4G1 axis in myeloid leukemia.


Assuntos
Leucemia Mieloide Aguda , Humanos , Proteína Proto-Oncogênica N-Myc , Sobrevivência Celular/genética , Leucemia Mieloide Aguda/genética , Carcinogênese , Células-Tronco Hematopoéticas
10.
Front Immunol ; 14: 1292568, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38090597

RESUMO

Introduction: Cytokines and chemokines play an important role in shaping innate and adaptive immunity in response to infection and vaccination. Systems serology identified immunological parameters predictive of beneficial response to the BNT162b2 mRNA vaccine in COVID-19 infection-naïve volunteers, COVID-19 convalescent patients and transplant patients with hematological malignancies. Here, we examined the dynamics of the serum cytokine/chemokine responses after the 3rd BNT162b2 mRNA vaccination in a cohort of COVID-19 infection-naïve volunteers. Methods: We measured serum cytokine and chemokine responses after the 3rd dose of the BNT162b2 mRNA (Pfizer/BioNtech) vaccine in COVID-19 infection-naïve individuals by a chemiluminescent assay and ELISA. Anti-Spike binding antibodies were measured by ELISA. Anti-Spike neutralizing antibodies were measured by a pseudotype assay. Results: Comparison to responses found after the 1st and 2nd vaccinations showed persistence of the coordinated responses of several cytokine/chemokines including the previously identified rapid and transient IL-15, IFN-γ, CXCL10/IP-10, TNF-α, IL-6 signature. In contrast to the transient (24hrs) effect of the IL-15 signature, an inflammatory/anti-inflammatory cytokine signature (CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1ß, CXCL8/IL-8, IL-1Ra) remained at higher levels up to one month after the 2nd and 3rd booster vaccinations, indicative of a state of longer-lasting innate immune change. We also identified a systemic transient increase of CXCL13 only after the 3rd vaccination, supporting stronger germinal center activity and the higher anti-Spike antibody responses. Changes of the IL-15 signature, and the inflammatory/anti-inflammatory cytokine profile correlated with neutralizing antibody levels also after the 3rd vaccination supporting their role as immune biomarkers for effective development of vaccine-induced humoral responses. Conclusion: These data revealed that repeated SARS-Cov-2 BNT162b2 mRNA vaccination induces both rapid transient as well as longer-lasting systemic serum cytokine changes associated with innate and adaptive immune responses. Clinical trial registration: Clinicaltrials.gov, identifier NCT04743388.


Assuntos
COVID-19 , Citocinas , Humanos , Vacina BNT162 , Interleucina-15 , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade Adaptativa , Vacinação , Anti-Inflamatórios
11.
Nat Commun ; 14(1): 6597, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37852965

RESUMO

Influenza virus infection causes increased morbidity and mortality in the elderly. Aging impairs the immune response to influenza, both intrinsically and because of altered interactions with endothelial and pulmonary epithelial cells. To characterize these changes, we performed single-cell RNA sequencing (scRNA-seq), spatial transcriptomics, and bulk RNA sequencing (bulk RNA-seq) on lung tissue from young and aged female mice at days 0, 3, and 9 post-influenza infection. Our analyses identified dozens of key genes differentially expressed in kinetic, age-dependent, and cell type-specific manners. Aged immune cells exhibited altered inflammatory, memory, and chemotactic profiles. Aged endothelial cells demonstrated characteristics of reduced vascular wound healing and a prothrombotic state. Spatial transcriptomics identified novel profibrotic and antifibrotic markers expressed by epithelial and non-epithelial cells, highlighting the complex networks that promote fibrosis in aged lungs. Bulk RNA-seq generated a timeline of global transcriptional activity, showing increased expression of genes involved in inflammation and coagulation in aged lungs. Our work provides an atlas of high-throughput sequencing methodologies that can be used to investigate age-related changes in the response to influenza virus, identify novel cell-cell interactions for further study, and ultimately uncover potential therapeutic targets to improve health outcomes in the elderly following influenza infection.


Assuntos
Influenza Humana , Infecções por Orthomyxoviridae , Humanos , Feminino , Animais , Camundongos , Idoso , Células Endoteliais , Pulmão/metabolismo , Células Epiteliais/metabolismo
12.
Animals (Basel) ; 13(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37760384

RESUMO

Monitoring the drinking behavior of animals can provide important information for livestock farming, including the health and well-being of the animals. Measuring drinking time is labor-demanding and, thus, it is still a challenge in most livestock production systems. Computer vision technology using a low-cost camera system can be useful in overcoming this issue. The aim of this research was to develop a computer vision system for monitoring beef cattle drinking behavior. A data acquisition system, including an RGB camera and an ultrasonic sensor, was developed to record beef cattle drinking actions. We developed an algorithm for tracking the beef cattle's key body parts, such as head-ear-neck position, using a state-of-the-art deep learning architecture DeepLabCut. The extracted key points were analyzed using a long short-term memory (LSTM) model to classify drinking and non-drinking periods. A total of 70 videos were used to train and test the model and 8 videos were used for validation purposes. During the testing, the model achieved 97.35% accuracy. The results of this study will guide us to meet immediate needs and expand farmers' capability in monitoring animal health and well-being by identifying drinking behavior.

13.
Adv Sci (Weinh) ; 10(28): e2206692, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37587835

RESUMO

Regulatory T (Treg) cells are inevitable to prevent deleterious immune responses to self and commensal microorganisms. Treg function requires continuous expression of the transcription factor (TF) FOXP3 and is divided into two major subsets: resting (rTregs) and activated (aTregs). Continuous T cell receptor (TCR) signaling plays a vital role in the differentiation of aTregs from their resting state, and in their immune homeostasis. The process by which Tregs differentiate, adapt tissue specificity, and maintain stable phenotypic expression at the transcriptional level is still inconclusivei. In this work, the role of BATF is investigated, which is induced in response to TCR stimulation in naïve T cells and during aTreg differentiation. Mice lacking BATF in Tregs developed multiorgan autoimmune pathology. As a transcriptional regulator, BATF is required for Treg differentiation, homeostasis, and stabilization of FOXP3 expression in different lymphoid and non-lymphoid tissues. Epigenetically, BATF showed direct regulation of Treg-specific genes involved in differentiation, maturation, and tissue accumulation. Most importantly, FOXP3 expression and Treg stability require continuous BATF expression in Tregs, as it regulates demethylation and accessibility of the CNS2 region of the Foxp3 locus. Considering its role in Treg stability, BATF should be considered an important therapeutic target in autoimmune disease.


Assuntos
Doenças Autoimunes , Linfócitos T Reguladores , Camundongos , Animais , Diferenciação Celular , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo
14.
Gut ; 72(11): 2103-2111, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37620120

RESUMO

OBJECTIVE: Braak's hypothesis states that Parkinson's disease (PD) originates in the gastrointestinal (GI) tract, and similar associations have been established for Alzheimer's disease (AD) and cerebrovascular diseases (CVD). We aimed to determine the incidence of GI syndromes and interventions preceding PD compared with negative controls (NCs), AD and CVD. DESIGN: We performed a combined case-control and cohort study using TriNetX, a US based nationwide medical record network. Firstly, we compared subjects with new onset idiopathic PD with matched NCs and patients with contemporary diagnoses of AD and CVD, to investigate preceding GI syndromes, appendectomy and vagotomy. Secondly, we compared cohorts with these exposures to matched NCs for the development of PD, AD and CVD within 5 years. RESULTS: We identified 24 624 PD patients in the case-control analysis and matched 18 cohorts with each exposure to their NCs. Gastroparesis, dysphagia, irritable bowel syndrome (IBS) without diarrhoea and constipation showed specific associations with PD (vs NCs, AD and CVD) in both the case-control (odds ratios (ORs) vs NCs 4.64, 3.58, 3.53 and 3.32, respectively, all p<0.0001) and cohort analyses (relative risks (RRs) vs NCs 2.43, 2.27, 1.17 and 2.38, respectively, all p<0.05). While functional dyspepsia, IBS with diarrhoea, diarrhoea and faecal incontinence were not PD specific, IBS with constipation and intestinal pseudo-obstruction showed PD specificity in the case-control (OR 4.11) and cohort analysis (RR 1.84), respectively. Appendectomy decreased the risk of PD in the cohort analysis (RR 0.48). Neither inflammatory bowel disease nor vagotomy were associated with PD. CONCLUSION: Dysphagia, gastroparesis, IBS without diarrhoea and constipation might specifically predict Parkinson's disease.

18.
NeuroRehabilitation ; 52(1): 93-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36617757

RESUMO

BACKGROUND: Parents often provide care to adult children veterans with polytrauma, traumatic brain injury, and/or post-traumatic stress disorder. OBJECTIVE: This two-arm randomized clinical trial compared interventions to help parent caregivers improve their depression, anxiety, and burden and manage care by decreasing troubling and concerning behaviors. METHODS: Interventions were six one-hour structured one-on-one behavioral sessions (REACH) or six 30-minute prerecorded online educational webinars. Both focused on knowledge, strategies for care, and coping, but REACH sessions were targeted, interactive, and skills-based. Quantitative and qualitative data were collected by telephone. Quantitative analyses included chi-squared test or independent samples t-test and repeated measures mixed linear modeling, with theme development for qualitative data. RESULTS: There were 163 parent caregivers, mostly mothers. During six months, participants in both arms improved significantly in depression, anxiety, burden, and reported veteran troubling and concerning behaviors. REACH caregivers showed a group by time improvement in concerning behaviors. Benefits included resources, self-reflection, not feeling alone, new skills, improved self-efficacy, and helping others. Specific concerns include exclusion from military and veteran care briefings and concern for the future. CONCLUSION: The positive response to both interventions provides opportunities for organizations with varying resources to provide support for parent caregivers. Interventions need to be targeted to parents' particular concerns and needs.


Assuntos
Veteranos , Adulto , Humanos , Filhos Adultos , Cuidadores , Pais , Adaptação Psicológica
19.
J Exp Med ; 220(1)2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36315049

RESUMO

Although recent evidence demonstrates heterogeneity among CD8+ T cells during chronic infection, developmental relationships and mechanisms underlying their fate decisions remain incompletely understood. Using single-cell RNA and TCR sequencing, we traced the clonal expansion and differentiation of CD8+ T cells during chronic LCMV infection. We identified immense clonal and phenotypic diversity, including a subset termed intermediate cells. Trajectory analyses and infection models showed intermediate cells arise from progenitor cells before bifurcating into terminal effector and exhausted subsets. Genetic ablation experiments identified that type I IFN drives exhaustion through an IRF7-dependent mechanism, possibly through an IFN-stimulated subset bridging progenitor and exhausted cells. Conversely, Zeb2 was critical for generating effector cells. Intriguingly, some T cell clones exhibited lineage bias. Mechanistically, we identified that TCR avidity correlates with an exhausted fate, whereas SHP-1 selectively restricts low-avidity effector cell accumulation. Thus, our work elucidates novel mechanisms underlying CD8+ T cell fate determination during persistent infection and suggests two potential pathways leading to exhaustion.


Assuntos
Linfócitos T CD8-Positivos , Infecção Persistente , Humanos , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Diferenciação Celular , Receptores de Antígenos de Linfócitos T/metabolismo
20.
Angiogenesis ; 26(2): 265-278, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36403190

RESUMO

Overcoming vascular immunosuppression: lack of endothelial cell (EC) responsiveness to inflammatory stimuli in the proangiogenic environment of tumors, is essential for successful cancer immunotherapy. The mechanisms through which Vascular Endothelial Growth Factor A(VEGF-A) modulates tumor EC response to exclude T-cells are not well understood. Here, we demonstrate that EC-specific deletion of small GTPase Rap1B, previously implicated in normal angiogenesis, restricts tumor growth in endothelial-specific Rap1B-knockout (Rap1BiΔEC) mice. EC-specific Rap1B deletion inhibits angiogenesis, but also leads to an altered tumor microenvironment with increased recruitment of leukocytes and increased activity of tumor CD8+ T-cells. Depletion of CD8+ T-cells restored tumor growth in Rap1BiΔEC mice. Mechanistically, global transcriptome and functional analyses indicated upregulation of signaling by a tumor cytokine, TNF-α, and increased NF-κB transcription in Rap1B-deficient ECs. Rap1B-deficiency led to elevated proinflammatory chemokine and Cell Adhesion Molecules (CAMs) expression in TNF-α stimulated ECs. Importantly, CAM expression was elevated in tumor ECs from Rap1BiΔEC mice. Significantly, Rap1B deletion prevented VEGF-A-induced immunosuppressive downregulation of CAM expression, demonstrating that Rap1B is essential for VEGF-A-suppressive signaling. Thus, our studies identify a novel endothelial-endogenous mechanism underlying VEGF-A-dependent desensitization of EC to proinflammatory stimuli. Significantly, they identify EC Rap1B as a potential novel vascular target in cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Células Endoteliais , Neoplasias , Proteínas rap de Ligação ao GTP , Animais , Camundongos , Linfócitos T CD8-Positivos/imunologia , Terapia de Imunossupressão , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neoplasias/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Células Endoteliais/imunologia , Células Endoteliais/fisiologia , NF-kappa B/genética , NF-kappa B/imunologia , Proteínas rap de Ligação ao GTP/genética , Proteínas rap de Ligação ao GTP/imunologia
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