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1.
Semin Cell Dev Biol ; 148-149: 3-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36526528

RESUMO

Plant diseases caused by soilborne pathogens are a major limiting factor in crop production. Bacterial wilt disease, caused by soilborne bacteria in the Ralstonia solanacearum Species Complex (Ralstonia), results in significant crop loss throughout the world. Ralstonia invades root systems and colonizes plant xylem, changing plant physiology and ultimately causing plant wilting in susceptible varieties. Elucidating how Ralstonia invades and colonizes plants is central to developing strategies for crop protection. Here we review Ralstonia pathogenesis from root detection and attachment, early root colonization, xylem invasion and subsequent wilting. We focus primarily on studies in tomato from the last 5-10 years. Recent work has identified elegant mechanisms Ralstonia uses to adapt to the plant xylem, and has discovered new genes that function in Ralstonia fitness in planta. A picture is emerging of an amazingly versatile pathogen that uses multiple strategies to make its surrounding environment more hospitable and can adapt to new environments.


Assuntos
Ralstonia solanacearum , Ralstonia , Virulência , Ralstonia solanacearum/genética , Plantas , Doenças das Plantas/microbiologia
2.
Plant J ; 113(5): 887-903, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36628472

RESUMO

A major challenge in global crop production is mitigating yield loss due to plant diseases. One of the best strategies to control these losses is through breeding for disease resistance. One barrier to the identification of resistance genes is the quantification of disease severity, which is typically based on the determination of a subjective score by a human observer. We hypothesized that image-based, non-destructive measurements of plant morphology over an extended period after pathogen infection would capture subtle quantitative differences between genotypes, and thus enable identification of new disease resistance loci. To test this, we inoculated a genetically diverse biparental mapping population of tomato (Solanum lycopersicum) with Ralstonia solanacearum, a soilborne pathogen that causes bacterial wilt disease. We acquired over 40 000 time-series images of disease progression in this population, and developed an image analysis pipeline providing a suite of 10 traits to quantify bacterial wilt disease based on plant shape and size. Quantitative trait locus (QTL) analyses using image-based phenotyping for single and multi-traits identified QTLs that were both unique and shared compared with those identified by human assessment of wilting, and could detect QTLs earlier than human assessment. Expanding the phenotypic space of disease with image-based, non-destructive phenotyping both allowed earlier detection and identified new genetic components of resistance.


Assuntos
Ralstonia solanacearum , Solanum lycopersicum , Humanos , Solanum lycopersicum/genética , Resistência à Doença/genética , Melhoramento Vegetal , Locos de Características Quantitativas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Progressão da Doença
3.
Blood ; 139(8): 1135-1146, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-34543383

RESUMO

Uproleselan (GMI-1271) is a novel E-selectin antagonist that disrupts cell survival pathways, enhances chemotherapy response, improves survival in mouse xenograft and syngeneic models, and decreases chemotherapy toxicity in vivo. A phase 1/2 study evaluated the safety, tolerability, and antileukemic activity of uproleselan (5-20 mg/kg) with MEC (mitoxantrone, etoposide, and cytarabine) among patients with relapsed/refractory (R/R) acute myeloid leukemia (AML). Among the first 19 patients, no dose-limiting toxicities were observed. The recommended phase 2 dose (RP2D) was 10 mg/kg twice daily. An additional 47 patients with R/R AML were treated with uproleselan at the RP2D plus MEC. At the RP2D, the remission rate (complete response [CR]/CR with incomplete count recovery [CRi]) was 41% (CR, 35%), and the median overall survival (OS) was 8.8 months. In a separate cohort, 25 newly diagnosed patients age ≥60 years received uproleselan at the RP2D plus cytarabine and idarubicin (7 + 3). In these frontline patients, the CR/CRi rate was 72% (CR, 52%), and the median OS was 12.6 months. The addition of uproleselan was associated with low rates of oral mucositis. E-selectin ligand expression on leukemic blasts was higher in patients with relapsed vs primary refractory AML and in newly diagnosed older patients with high-risk cytogenetics and secondary AML. In the R/R cohort, E-selectin expression >10% was associated with a higher response rate and improved survival. The addition of uproleselan to chemotherapy was well tolerated, with high remission rates, low induction mortality, and low rates of mucositis, providing a strong rationale for phase 3 randomized confirmatory studies. This trial was registered at www.clinicaltrials.gov as #NCT02306291.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Glicolipídeos/administração & dosagem , Leucemia Mieloide Aguda , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Glicolipídeos/efeitos adversos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/efeitos adversos , Taxa de Sobrevida
4.
J Rheumatol ; 51(3): 234-241, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224981

RESUMO

A bimodal pattern of mortality in systemic lupus erythematosus (SLE) exists. Early-stage deaths are predominantly caused by infection, whereas later-stage deaths are mainly caused by atherosclerotic disease. Further, although SLE-related mortality has reduced considerably in recent years, cardiovascular (CV) events remain one of the leading causes of death in people with SLE. Accelerated atherosclerosis in SLE is attributed to both an increase in traditional CV risk factors and the inflammatory effects of SLE itself. Many of these changes occur within the microenvironment of the vascular-immune interface, the site of atherosclerotic plaque development. Here, an intimate interaction between endothelial cells, vascular smooth muscle cells, and immune cells dictates physiological vs pathological responses to a chronic type 1 interferon environment. Low-density neutrophils (LDNs) have also been implicated in eliciting vasculature-damaging effects at such lesion sites. These changes are thought to be governed by dysfunctional metabolism of immune cells in this niche due at least in part to the chronic induction of type 1 interferons. Understanding these novel pathophysiological mechanisms and metabolic pathways may unveil potential innovative pharmacological targets and therapeutic opportunities for atherosclerosis, as well as shed light on the development of premature atherosclerosis in patients with SLE who develop CV events.


Assuntos
Aterosclerose , Lúpus Eritematoso Sistêmico , Doenças Reumáticas , Humanos , Células Endoteliais , Fatores de Risco , Aterosclerose/etiologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Doenças Reumáticas/complicações
5.
Phytopathology ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717940

RESUMO

Phyllachora maydis is an ascomycete foliar fungal pathogen and the causal agent of tar spot in maize. Though P. maydis is considered an economically important foliar pathogens of maize, our general knowledge of the trophic lifestyle and functional role of effector proteins from this fungal pathogen remains limited. Here, we utilized a genome-informed approach to predict the trophic lifestyle of P. maydis and functionally characterized a subset of candidate effectors from this fungal pathogen. Leveraging the most recent P. maydis genome annotation and the CATAStrophy pipeline, we show this fungal pathogen encodes a predicted Carbohydrate-active enzymes (CAZymes) repertoire consistent with that of biotrophs. To investigate fungal pathogenicity, we selected 18 candidate effector proteins that were previously shown to be expressed during primary disease development. We assessed whether these putative effectors share predicted structural similarity with other characterized fungal effectors and determined whether any suppress plant immune responses. Using AlphaFold2 and Foldseek, we showed one candidate effector, PM02_g1115, adopts a predicted protein structure similar to that of an effector from Verticillium dahlia. Furthermore, transient expression of candidate effector-fluorescent protein fusions in Nicotiana benthamiana revealed two putative effectors, PM02_g378 and PM02_g2610, accumulated predominantly in the cytosol, and three candidate effectors, PM02_g1115, PM02_g7882, and PM02_g8240 consistently attenuated chitin-mediated reactive oxygen species production. Collectively, these results presented herein provide insights into the predicted trophic lifestyle and putative functions of effectors from P. maydis and will likely stimulate continued research to elucidate the molecular mechanisms used by P. maydis to induce tar spot.

6.
Oncologist ; 28(10): 901-910, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37120291

RESUMO

BACKGROUND: Older patients with myelodysplastic syndromes (MDS), particularly those with no or one cytopenia and no transfusion dependence, typically have an indolent course. Approximately, half of these receive the recommended diagnostic evaluation (DE) for MDS. We explored factors determining DE in these patients and its impact on subsequent treatment and outcomes. PATIENTS AND METHODS: We used 2011-2014 Medicare data to identify patients ≥66 years of age diagnosed with MDS. We used Classification and Regression Tree (CART) analysis to identify combinations of factors associated with DE and its impact on subsequent treatment. Variables examined included demographics, comorbidities, nursing home status, and investigative procedures performed. We conducted a logistic regression analysis to identify correlates associated with receipt of DE and treatment. RESULTS: Of 16 851 patients with MDS, 51% underwent DE. patients with MDS with no cytopenia (n = 3908) had the lowest uptake of DE (34.7%). Compared to patients with no cytopenia, those with any cytopenia had nearly 3 times higher odds of receiving DE [adjusted odds ratio (AOR), 2.81: 95% CI, 2.60-3.04] and the odds were higher for men than for women [AOR, 1.39: 95%CI, 1.30-1.48] and for Non-Hispanic Whites [vs. everyone else (AOR, 1.17: 95% CI, 1.06-1.29)]. The CART showed DE as the principal discriminating node, followed by the presence of any cytopenia for receiving MDS treatment. The lowest percentage of treatment was observed in patients without DE, at 14.6%. CONCLUSION: In this select older patients with MDS, we identified disparities in accurate diagnosis by demographic and clinical factors. Receipt of DE influenced subsequent treatment but not survival.


Assuntos
Anemia , Síndromes Mielodisplásicas , Masculino , Humanos , Feminino , Idoso , Estados Unidos/epidemiologia , Medicare , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Comorbidade
7.
Cell Immunol ; 390: 104741, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37356269

RESUMO

Although clinically effective, the actions of IFNα, either produced endogenously or by therapeutic delivery, remain poorly understood. Emblematic of this research gap is the disparate array of notable side effects that occur in susceptible individuals, such as neuropsychiatric consequences, autoimmune phenomena, and infectious complications. We hypothesised that these complications are driven at least in part by dysregulated cellular metabolism. Male Wistar rats were treated with either 170,000 IU/kg human recombinant IFNα-2a or BSA/saline (0.9% NaCl) three times per week for three weeks. Bone marrow (BM) immune cells were isolated from the excised femurs for glycolytic rate and mitochondrial function assessment using Agilent Seahorse Technology. Frequencies of immune cell populations were assessed by flow cytometry to determine whether leukopoietic changes had occurred in both blood and BM. Plasma levels of lactate and succinate were also determined. BMDMs were metabolically assessed as above, as well as their metabolic response to an antigenic stimulus (iH37Rv). We observed that BM immune cells from IFN-treated rats exhibit a hypermetabolic state (increased basal OCR/GlycoPER) with decreased mitochondrial metabolic respiration and increased non-mitochondrial OCR. Flow cytometry results indicated an increase in immature granulocytes (RP1- SSChi CD45lo) only in the blood, together with increased succinate levels in the plasma. BMDMs from IFN-treated rats retained the hypermetabolic phenotype after differentiation and failed to induce a step-up in glycolysis and mitochondrial respiration after bacterial stimulation. This work provides the first evidence of the effects of IFNα treatment in inducing hypermetabolic immune features that are associated with markers of inflammation, leukopoiesis, and defective responses to bacterial stimulation.


Assuntos
Interferon-alfa , Ácido Succínico , Humanos , Masculino , Ratos , Animais , Ácido Succínico/metabolismo , Ratos Wistar , Interferon-alfa/farmacologia , Mitocôndrias/metabolismo , Succinatos/metabolismo
8.
Plant Cell Environ ; 46(10): 3040-3058, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36213953

RESUMO

Plant disease limits crop production, and host genetic resistance is a major means of control. Plant pathogenic Ralstonia causes bacterial wilt disease and is best controlled with resistant varieties. Tomato wilt resistance is multigenic, yet the mechanisms of resistance remain largely unknown. We combined metaRNAseq analysis and functional experiments to identify core Ralstonia-responsive genes and the corresponding biological mechanisms in wilt-resistant and wilt-susceptible tomatoes. While trade-offs between growth and defence are common in plants, wilt-resistant plants activated both defence responses and growth processes. Measurements of innate immunity and growth, including reactive oxygen species production and root system growth, respectively, validated that resistant plants executed defence-related processes at the same time they increased root growth. In contrast, in wilt-susceptible plants roots senesced and root surface area declined following Ralstonia inoculation. Wilt-resistant plants repressed genes predicted to negatively regulate water stress tolerance, while susceptible plants repressed genes predicted to promote water stress tolerance. Our results suggest that wilt-resistant plants can simultaneously promote growth and defence by investing in resources that act in both processes. Infected susceptible plants activate defences, but fail to grow and so succumb to Ralstonia, likely because they cannot tolerate the water stress induced by vascular wilt.


Assuntos
Doenças das Plantas , Solanum lycopersicum , Desidratação , Genes de Plantas , Doenças das Plantas/microbiologia , Solanum lycopersicum/genética , Solanum lycopersicum/microbiologia
9.
Blood ; 138(19): 1885-1895, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34075412

RESUMO

Although genomic alterations drive the pathogenesis of acute myeloid leukemia (AML), traditional classifications are largely based on morphology, and prototypic genetic founder lesions define only a small proportion of AML patients. The historical subdivision of primary/de novo AML and secondary AML has shown to variably correlate with genetic patterns. The combinatorial complexity and heterogeneity of AML genomic architecture may have thus far precluded genomic-based subclassification to identify distinct molecularly defined subtypes more reflective of shared pathogenesis. We integrated cytogenetic and gene sequencing data from a multicenter cohort of 6788 AML patients that were analyzed using standard and machine learning methods to generate a novel AML molecular subclassification with biologic correlates corresponding to underlying pathogenesis. Standard supervised analyses resulted in modest cross-validation accuracy when attempting to use molecular patterns to predict traditional pathomorphologic AML classifications. We performed unsupervised analysis by applying the Bayesian latent class method that identified 4 unique genomic clusters of distinct prognoses. Invariant genomic features driving each cluster were extracted and resulted in 97% cross-validation accuracy when used for genomic subclassification. Subclasses of AML defined by molecular signatures overlapped current pathomorphologic and clinically defined AML subtypes. We internally and externally validated our results and share an open-access molecular classification scheme for AML patients. Although the heterogeneity inherent in the genomic changes across nearly 7000 AML patients was too vast for traditional prediction methods, machine learning methods allowed for the definition of novel genomic AML subclasses, indicating that traditional pathomorphologic definitions may be less reflective of overlapping pathogenesis.


Assuntos
Leucemia Mieloide Aguda/genética , Aprendizado de Máquina , Teorema de Bayes , Citogenética , Regulação Leucêmica da Expressão Gênica , Genômica , Humanos , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/diagnóstico , Mutação , Segunda Neoplasia Primária/classificação , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/genética , Translocação Genética
10.
Blood ; 137(6): 751-762, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32929488

RESUMO

Approximately 50% of acute myeloid leukemia (AML) patients do not respond to induction therapy (primary induction failure [PIF]) or relapse after <6 months (early relapse [ER]). We have recently shown an association between an immune-infiltrated tumor microenvironment (TME) and resistance to cytarabine-based chemotherapy but responsiveness to flotetuzumab, a bispecific DART antibody-based molecule to CD3ε and CD123. This paper reports the results of a multicenter, open-label, phase 1/2 study of flotetuzumab in 88 adults with relapsed/refractory AML: 42 in a dose-finding segment and 46 at the recommended phase 2 dose (RP2D) of 500 ng/kg per day. The most frequent adverse events were infusion-related reactions (IRRs)/cytokine release syndrome (CRS), largely grade 1-2. Stepwise dosing during week 1, pretreatment dexamethasone, prompt use of tocilizumab, and temporary dose reductions/interruptions successfully prevented severe IRR/CRS. Clinical benefit accrued to PIF/ER patients showing an immune-infiltrated TME. Among 30 PIF/ER patients treated at the RP2D, the complete remission (CR)/CR with partial hematological recovery (CRh) rate was 26.7%, with an overall response rate (CR/CRh/CR with incomplete hematological recovery) of 30.0%. In PIF/ER patients who achieved CR/CRh, median overall survival was 10.2 months (range, 1.87-27.27), with 6- and 12-month survival rates of 75% (95% confidence interval [CI], 0.450-1.05) and 50% (95% CI, 0.154-0.846). Bone marrow transcriptomic analysis showed that a parsimonious 10-gene signature predicted CRs to flotetuzumab (area under the receiver operating characteristic curve = 0.904 vs 0.672 for the European LeukemiaNet classifier). Flotetuzumab represents an innovative experimental approach associated with acceptable safety and encouraging evidence of activity in PIF/ER patients. This trial was registered at www.clinicaltrials.gov as #NCT02152956.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Imunoterapia , Leucemia Mieloide Aguda/terapia , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Síndrome da Liberação de Citocina/induzido quimicamente , Síndrome da Liberação de Citocina/tratamento farmacológico , Relação Dose-Resposta Imunológica , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Feminino , Seguimentos , Hematopoese/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Mapas de Interação de Proteínas , Taxa de Sobrevida
11.
J Exp Bot ; 74(10): 3047-3059, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-36787214

RESUMO

The root cap is a small tissue located at the tip of the root with critical functions for root growth. Present in nearly all vascular plants, the root cap protects the root meristem, influences soil penetration, and perceives and transmits environmental signals that are critical for root branching patterns. To perform these functions, the root cap must remain relatively stable in size and must integrate endogenous developmental pathways with environmental signals, yet the mechanism is not clear. We previously showed that low pH conditions altered root cap development, and these changes are mediated by the NIN LIKE PROTEIN 7 (NLP7) transcription factor, a master regulator of nitrate signaling. Here we show that in Arabidopsis NLP7 integrates nitrate signaling with auxin pathways to regulate root cap development. We found that low nitrate conditions promote aberrant release of root cap cells. Nitrate deficiency impacts auxin pathways in the last layer of the root cap, and this is mediated in part by NLP7. Mutations in NLP7 abolish the auxin minimum in the last layer of the root cap and alter root cap expression of the auxin carriers PIN-LIKES 3 (PILS3) and PIN-FORMED 7 (PIN7) as well as transcription factors that regulate PIN expression. Together, our data reveal NLP7 as a link between endogenous auxin pathways and nitrate signaling in the root cap.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Nitratos/metabolismo , Raízes de Plantas/metabolismo , Meristema , Regulação da Expressão Gênica de Plantas
12.
Lupus ; 32(5): 603-611, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36914582

RESUMO

The association of dysregulated metabolism in systemic lupus erythematosus (SLE) pathogenesis has prompted investigations into metabolic rewiring and the involvement of mitochondrial metabolism as a driver of disease through NLRP3 inflammasome activation, disruption of mitochondrial DNA maintenance, and pro-inflammatory cytokine release. The use of Agilent Seahorse Technology to gain functional in situ metabolic insights of selected cell types from SLE patients has identified key parameters that are dysregulated during disease. Mitochondrial functional assessments specifically can detect dysfunction through oxygen consumption rate (OCR), spare respiratory capacity, and maximal respiration measurements, which, when coupled with disease activity scores could show potential as markers of disease activity. CD4+ and CD8 + T cells have been assessed in this way and show that oxygen consumption rate, spare respiratory capacity, and maximal respiration are blunted in CD8 + T cells, with results not being as clear cut in CD4 + T cells. Additionally, glutamine, processed by mitochondrial substrate level phosphorylation is emerging as a key role player in the expansion and differentiation of Th1, Th17, ϒδ T cells, and plasmablasts. The role that circulating leukocytes play in acting as bioenergetic biomarkers of diseases such as diabetes suggests that this may also be a tool to detect preclinical SLE. Therefore, the metabolic characterization of immune cell subsets and the collection of metabolic data during interventions is also essential. The delineation of the metabolic tuning of immune cells in this way could lead to novel strategies in treating metabolically demanding processes characteristic of autoimmune diseases such as SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Metabolismo Energético , Mitocôndrias , Subpopulações de Linfócitos T
13.
Phytopathology ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38079374

RESUMO

Tar spot, a disease caused by the ascomycete fungal pathogen Phyllachora maydis, is considered one of the most significant yield-limiting diseases of maize (Zea mays L.) within the United States. P. maydis may also be found in association with other fungi, forming a disease complex which is thought to result in the characteristic fish eye lesions. Understanding how P. maydis colonizes maize leaf cells is essential for developing effective disease control strategies. Here, we used histological approaches to elucidate how P. maydis infects and multiplies within susceptible maize leaves. We collected tar spot-infected maize leaf samples from four different fields in northern Indiana at three different time points during the growing season. Samples were chemically fixed and paraffin-embedded for high-resolution light and scanning electron microscopy. We observed a consistent pattern of disease progression in independent leaf samples collected across different geographical regions. Each stroma contained a central pycnidium that produced asexual spores. Perithecia with sexual spores developed in the stomatal chambers adjacent to the pycnidium, and a cap of spores formed over the stroma. P. maydis reproductive structures formed around but not within the vasculature. We observed P. maydis associated with two additional fungi, one of which is likely a member of the Paraphaeosphaeria genus; the other is an unknown fungi. Our data provide fundamental insights into how this pathogen colonizes and spreads within maize leaves. This knowledge can inform new approaches to managing tar spot, which could help mitigate the significant economic losses caused by this disease.

14.
J Exp Bot ; 73(16): 5758-5772, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35596672

RESUMO

Utilizing beneficial microbes for crop improvement is one strategy to achieve sustainable agriculture. However, identifying microbial isolates that promote crop growth is challenging, in part because using bacterial taxonomy to predict an isolate's effect on plant growth may not be reliable. The overall aim of this work was to determine whether in vitro functional traits of bacteria were predictive of their in planta impact. We isolated 183 bacterial endophytes from field-grown roots of two tomato species, Solanum lycopersicum and S. pimpinellifolium. Sixty isolates were screened for six in vitro functional traits: auxin production, siderophore production, phosphate solubilization, antagonism to a soilborne pathogen, and the presence of two antimicrobial metabolite synthesis genes. Hierarchical clustering of the isolates based on the in vitro functional traits identified several groups of isolates sharing similar traits. We called these groups 'functional groups'. To understand how in vitro functional traits of bacteria relate to their impact on plants, we inoculated three isolates from each of the functional groups on tomato seedlings. Isolates within the same functional group promoted plant growth at similar levels, regardless of their host origin or taxonomy. Together, our results demonstrate the importance of examining root endophyte functions for improving crop production.


Assuntos
Endófitos , Solanum lycopersicum , Bactérias/metabolismo , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/metabolismo , Desenvolvimento Vegetal , Raízes de Plantas/metabolismo
15.
Phytopathology ; 112(12): 2538-2548, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35815936

RESUMO

Most fungal pathogens secrete effector proteins into host cells to modulate their immune responses, thereby promoting pathogenesis and fungal growth. One such fungal pathogen is the ascomycete Phyllachora maydis, which causes tar spot disease on leaves of maize (Zea mays). Sequencing of the P. maydis genome revealed 462 putatively secreted proteins, of which 40 contain expected effector-like sequence characteristics. However, the subcellular compartments targeted by P. maydis effector candidate (PmEC) proteins remain unknown, and it will be important to prioritize them for further functional characterization. To test the hypothesis that PmECs target diverse subcellular compartments, cellular locations of super yellow fluorescent protein-tagged PmEC proteins were identified using a Nicotiana benthamiana-based heterologous expression system. Immunoblot analyses showed that most of the PmEC-fluorescent protein fusions accumulated protein in N. benthamiana, indicating that the candidate effectors could be expressed in dicot leaf cells. Laser-scanning confocal microscopy of N. benthamiana epidermal cells revealed that most of the P. maydis putative effectors localized to the nucleus and cytosol. One candidate effector, PmEC01597, localized to multiple subcellular compartments including the nucleus, nucleolus, and plasma membrane, whereas an additional putative effector, PmEC03792, preferentially labelled both the nucleus and nucleolus. Intriguingly, one candidate effector, PmEC04573, consistently localized to the stroma of chloroplasts as well as stroma-containing tubules (stromules). Collectively, these data suggest that effector candidate proteins from P. maydis target diverse cellular organelles and could thus provide valuable insights into their putative functions, as well as host processes potentially manipulated by this fungal pathogen.


Assuntos
Doenças das Plantas , Zea mays , Doenças das Plantas/microbiologia , Zea mays/microbiologia , Células Vegetais/metabolismo , Phyllachorales/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
16.
Cancer ; 127(6): 905-913, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33231879

RESUMO

BACKGROUND: Patients with relapsed/refractory (R/R) Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) have a poor prognosis and limited treatment options. METHODS: The efficacy of inotuzumab ozogamicin (InO), a humanized anti-CD22 monoclonal antibody conjugated to the cytotoxic antibiotic calicheamicin, was evaluated in R/R ALL patients in the phase 1/2 study 1010 (NCT01363297) and open-label, randomized, phase 3 study 1022 (INO-VATE; NCT01564784). This analysis focused specifically on Ph+ R/R ALL patients. In study 1022, Ph+ patients were randomly assigned 1:1 to InO (n = 22) or standard intensive chemotherapy (SC) (n = 27) and 16 Ph+ patients in study 1010 received InO. RESULTS: In study 1022, rates of complete remission/complete remission with incomplete hematologic recovery (CR/CRi) and minimal residual disease (MRD) negativity (patients achieving CR/CRi) were higher with InO (CR/CRi = 73%; MRD = 81%) versus SC (CR/CRi = 56%; MRD = 33%). The corresponding rates in study 1010 were 56% (CR/CRi) and 100% (MRD). The hematopoietic stem cell transplantation (HSCT) rate in study 1022 was 41% versus 19% for InO versus SC; however, there was no benefit in overall survival (median OS: 8.7 vs 8.4 months; hazard ratio, 1.17 [95% CI, 0.64-2.14]). The probability of being event-free (progression-free survival) at 12 months was greater with InO versus SC (20.1% vs 4.8%). CONCLUSION: Given the substantial improvement in responses and rates of HSCT, InO is an important treatment option for patients with R/R Ph+ ALL. Future studies need to consider better characterization of disease characteristics, more sensitive MRD measurements, MRD-directed therapy before HSCT, and potentially combination therapies, including tyrosine kinase inhibitors.


Assuntos
Inotuzumab Ozogamicina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Humanos , Neoplasia Residual , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Recidiva
17.
Cancer ; 127(7): 1039-1048, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33259056

RESUMO

BACKGROUND: The availability of novel agents (NAs), including blinatumomab and inotuzumab ozogamicin (InO), has improved the outcomes of patients with relapsed/refractory (RR) B-cell acute lymphoblastic leukemia (ALL). Because of the relative effectiveness, it is often a challenge for clinicians to determine how to best sequence these NAs with respect to efficacy and toxicity. METHODS: In this multicenter, retrospective study of patients with RR ALL treated with blinatumomab, InO, or both, their efficacy as a first or second NA was compared. RESULTS: Among 276 patients, 221 and 55 received blinatumomab and InO, respectively, as a first NA therapy. The complete remission (CR)/complete remission with incomplete count recovery (CRi) rate was 65% and 67% for the blinatumomab and InO groups, respectively (P = .73). The rate of treatment discontinuation due to adverse events was 4% and 7% in the blinatumomab and InO groups, respectively. Ninety-two patients (43%) in the blinatumomab group and 13 patients (29%) in the InO group proceeded with allogeneic hematopoietic stem cell transplantation. The median overall survival (OS) was 15 and 11.6 months in the blinatumomab and InO groups, respectively. A subset analysis was performed for 61 patients who received both NAs (blinatumomab and then InO [n = 40] or InO and then blinatumomab [n = 21]). The CR/CRi rate was 58% for patients who received InO as the second NA and 52% for patients who received blinatumomab as the second NA. The median OS was 10.5 for patients who received InO as the second NA and 5.9 months for patients who received blinatumomab as the second NA (P = .09). CONCLUSIONS: Although the limited power of this study to detect a significant difference between subgroups is acknowledged, the data suggest that blinatumomab and InO may have comparable efficacy as a first or second NA therapy in RR ALL.


Assuntos
Anticorpos Biespecíficos/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Inotuzumab Ozogamicina/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Biespecíficos/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Feminino , Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Humanos , Inotuzumab Ozogamicina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento , Suspensão de Tratamento/estatística & dados numéricos , Adulto Jovem
18.
Blood ; 133(14): 1548-1559, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30658992

RESUMO

Retrospective studies have suggested that older adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) have better survival rates when treated using a pediatric ALL regimen administered by pediatric treatment teams. To address the feasibility and efficacy of using a pediatric treatment regimen for AYA patients with newly diagnosed ALL administered by adult treatment teams, we performed a prospective study, CALGB 10403, with doses and schedule identical to those in the Children's Oncology Group study AALL0232. From 2007 to 2012, 318 patients were enrolled; 295 were eligible and evaluable for response. Median age was 24 years (range, 17-39 years). Use of the pediatric regimen was safe; overall treatment-related mortality was 3%, and there were only 2 postremission deaths. Median event-free survival (EFS) was 78.1 months (95% confidence interval [CI], 41.8 to not reached), more than double the historical control of 30 months (95% CI, 22-38 months); 3-year EFS was 59% (95% CI, 54%-65%). Median overall survival (OS) was not reached. Estimated 3-year OS was 73% (95% CI, 68%-78%). Pretreatment risk factors associated with worse treatment outcomes included obesity and presence of the Philadelphia-like gene expression signature. Use of a pediatric regimen for AYAs with ALL up to age 40 years was feasible and effective, resulting in improved survival rates compared with historical controls. CALGB 10403 can be considered a new treatment standard upon which to build for improving survival for AYAs with ALL. This trial was registered at www.clinicaltrials.gov as #NCT00558519.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Adulto , Esquema de Medicação , Feminino , Estudo Historicamente Controlado , Humanos , Masculino , Obesidade , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
19.
Phytopathology ; 111(12): 2213-2226, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33720750

RESUMO

Phytopathogenic bacteria secrete type III effector (T3E) proteins directly into host plant cells. T3Es can interact with plant proteins and frequently manipulate plant host physiological or developmental processes. The proper subcellular localization of T3Es is critical for their ability to interact with plant targets, and knowledge of T3E localization can be informative for studies of effector function. Here we investigated the subcellular localization of 19 T3Es from the phytopathogenic bacteria Ralstonia pseudosolanacearum and Ralstonia solanacearum. Approximately 45% of effectors in our library localize to both the plant cell periphery and the nucleus, 15% exclusively to the cell periphery, 15% exclusively to the nucleus, and 25% to other organelles, including tonoplasts and peroxisomes. Using tomato hairy roots, we show that T3E localization is similar in both leaves and roots and is not impacted by Solanum species. We find that in silico prediction programs are frequently inaccurate, highlighting the value of in planta localization experiments. Our data suggest that Ralstonia targets a wide diversity of cellular organelles and provides a foundation for developing testable hypotheses about Ralstonia effector function.


Assuntos
Ralstonia solanacearum , Solanum , Proteínas de Bactérias , Organelas , Doenças das Plantas , Virulência
20.
Biol Blood Marrow Transplant ; 26(8): 1505-1510, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32439476

RESUMO

Hematopoietic cell transplantation (HCT) is physically and psychologically challenging, potentially exposing patients to quality-of-life (QoL) impairments. Adolescent and young adults (AYAs, aged 15 to 39 years) are a vulnerable cohort facing multiple hurdles due to dynamic changes in several aspects of their lives. The AYA population may be particularly prone to QoL issues during HCT. We hypothesized that due to the unique psychosocial challenges faced by AYAs, they would have an inferior quality of life. We studied QoL differences between AYA (aged 15 to 39 years) and older adult (aged 40 to 60 years) allogeneic HCT recipients before and after HCT. Additionally, we determined if pre-HCT QoL for AYA transplant recipients changed over time. QoL data were collected prospectively before and after transplant on 431 recipients aged 15 to 60 years from June 2003 through December 2017 using the Functional Assessment of Cancer Therapy-Bone Marrow Transplantation (FACT-BMT) questionnaire. Repeated-measures analysis of variance was used to assess differences among age groups. Pearson correlation (r) was used to determine if baseline QoL had improved after HCT from June 2003 through December 2017 in the AYA cohort. QoL did not differ among younger AYAs, older AYAs, or older adults at any time in the first year after allogeneic HCT. At 1 year post-HCT, total FACT-BMT score and all FACT-BMT domains except physical well-being improved from pre-HCT in all age groups. From 2003 to 2017, AYA allogeneic recipients experienced modest improvement in additional concerns (r = 0.26, P = .003), trial outcome index (r = 0.23, P = .008), and total FACT-BMT score (r = 0.19, P = .031), although no improvements were seen in physical, social, emotional, or functional well-being. Contrary to our hypothesis, we found that QoL in the AYA population is similar to that of older adults before and after HCT. Improvements in QoL of AYA allogeneic patients since 2003 were driven by the additional concerns domain, which addresses multiple psychosocial aspects such as vocation, hobbies, and acceptance of illness. Continued efforts to tailor treatment and support for AYA HCT recipients is critical to improving QoL outcomes.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Qualidade de Vida , Adolescente , Idoso , Transplante de Medula Óssea , Humanos , Inquéritos e Questionários , Transplantados , Adulto Jovem
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