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1.
J Immunol ; 208(5): 1272-1279, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35110420

RESUMO

Interstitial macrophages (IMs) are key regulators of allergic inflammation. We previously showed that the absence of semaphorin 3E (Sema3E) exacerbates asthma features in both acute and chronic asthma models. However, it has not been studied whether Sema3E, via its receptor plexinD1, regulates IM function in allergic asthma. Therefore, we investigated the role of plexinD1 deficiency on IMs in allergic asthma. We found that the absence of plexinD1 in IMs increased airway hyperresponsiveness, airway leukocyte numbers, allergen-specific IgE, goblet cell hyperplasia, and Th2/Th17 cytokine response in the house dust mite (HDM)-induced allergic asthma model. Muc5ac, Muc5b, and α-SMA genes were increased in mice with Plxnd1-deficient IMs compared with wild-type mice. Furthermore, plexinD1-deficient bone marrow-derived macrophages displayed reduced IL-10 mRNA expression, at both the baseline and following HDM challenge, compared with their wild-type counterpart mice. Our data suggest that Sema3E/plexinD1 signaling in IMs is a critical pathway that modulates airway inflammation, airway resistance, and tissue remodeling in the HDM murine model of allergic asthma. Reduced IL-10 expression by plexinD1-deficient macrophages may account for these enhanced allergic asthma features.


Assuntos
Asma/patologia , Dermatophagoides pteronyssinus/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Macrófagos/imunologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Semaforinas/genética , Actinas/genética , Actinas/metabolismo , Resistência das Vias Respiratórias/imunologia , Animais , Asma/imunologia , Modelos Animais de Doenças , Feminino , Células Caliciformes/imunologia , Imunoglobulina E/imunologia , Interleucina-10/genética , Contagem de Leucócitos , Leucócitos/imunologia , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Mucina-5AC/genética , Mucina-5AC/metabolismo , Mucina-5B/genética , Mucina-5B/metabolismo , RNA Mensageiro/genética , Células Th17/imunologia , Células Th2/imunologia
2.
PLoS Pathog ; 17(9): e1009944, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34543348

RESUMO

Intracellular infection with the parasite Leishmania major features a state of concomitant immunity in which CD4+ T helper 1 (Th1) cell-mediated immunity against reinfection coincides with a chronic but sub-clinical primary infection. In this setting, the rapidity of the Th1 response at a secondary site of challenge in the skin represents the best correlate of parasite elimination and has been associated with a reversal in Leishmania-mediated modulation of monocytic host cells. Remarkably, the degree to which Th1 cells are absolutely reliant upon the time at which they interact with infected monocytes to mediate their protective effect has not been defined. In the present work, we report that CXCR3-dependent recruitment of Ly6C+ Th1 effector (Th1EFF) cells is indispensable for concomitant immunity and acute (<4 days post-infection) Th1EFF cell-phagocyte interactions are critical to prevent the establishment of a permissive pathogen niche, as evidenced by altered recruitment, gene expression and functional capacity of innate and adaptive immune cells at the site of secondary challenge. Surprisingly, provision of Th1EFF cells after establishment of the pathogen niche, even when Th1 cells were provided in large quantities, abrogated protection, Th1EFF cell accumulation and IFN-γ production, and iNOS production by inflammatory monocytes. These findings indicate that protective Th1 immunity is critically dependent on activation of permissive phagocytic host cells by preactivated Th1EFF cells at the time of infection.


Assuntos
Imunidade Celular/imunologia , Leishmaniose Cutânea/imunologia , Monócitos/imunologia , Células Th1/imunologia , Animais , Leishmania major/imunologia , Camundongos Endogâmicos C57BL
3.
Microb Ecol ; 86(4): 2790-2801, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37563275

RESUMO

High-throughput, multiplexed-amplicon sequencing has become a core tool for understanding environmental microbiomes. As researchers have widely adopted sequencing, many open-source analysis pipelines have been developed to compare microbiomes using compositional analysis frameworks. However, there is increasing evidence that compositional analyses do not provide the information necessary to accurately interpret many community assembly processes. This is especially true when there are large gradients that drive distinct community assembly processes. Recently, sequencing has been combined with Q-PCR (among other sources of total quantitation) to generate "Quantitative Sequencing" (QSeq) data. QSeq more accurately estimates the true abundance of taxa, is a more reliable basis for inferring correlation, and, ultimately, can be more reliably related to environmental data to infer community assembly processes. In this paper, we use a combination of published data sets, synthesis, and empirical modeling to offer guidance for which contexts QSeq is advantageous. As little as 5% variation in total abundance among experimental groups resulted in more accurate inference by QSeq than compositional methods. Compositional methods for differential abundance and correlation unreliably detected patterns in abundance and covariance when there was greater than 20% variation in total abundance among experimental groups. Whether QSeq performs better for beta diversity analysis depends on the question being asked, and the analytic strategy (e.g., what distance metric is being used); for many questions and methods, QSeq and compositional analysis are equivalent for beta diversity analysis. QSeq is especially useful for taxon-specific analysis; QSeq transformation and analysis should be the default for answering taxon-specific questions of amplicon sequence data. Publicly available bioinformatics pipelines should incorporate support for QSeq transformation and analysis.


Assuntos
Bactérias , Microbiota , Bactérias/genética , Densidade Demográfica , Microbiota/genética , Análise de Sequência de DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos
4.
J Immunol ; 206(5): 1013-1026, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33462138

RESUMO

There is currently no effective vaccine against leishmaniasis because of the lack of sufficient knowledge about the Ags that stimulate host-protective and long-lasting T cell-mediated immunity. We previously identified Leishmania phosphoenolpyruvate carboxykinase (PEPCK, a gluconeogenic enzyme) as an immunodominant Ag that is expressed by both the insect (promastigote) and mammalian (amastigote) stages of the parasite. In this study, we investigated the role of PEPCK in metabolism, virulence, and immunopathogenicity of Leishmania major We show that targeted loss of PEPCK results in impaired proliferation of L. major in axenic culture and bone marrow-derived macrophages. Furthermore, the deficiency of PEPCK results in highly attenuated pathology in vivo. BALB/c mice infected with PEPCK-deficient parasites failed to develop any cutaneous lesions despite harboring parasites at the cutaneous site of infection. This was associated with a dramatic reduction in the frequency of cytokine (IFN-γ, IL-4, and IL-10)-producing CD4+ T cells in spleens and lymph nodes draining the infection site. Cells from mice infected with PEPCK-deficient parasites also produced significantly low levels of these cytokines into the culture supernatant following in vitro restimulation with soluble Leishmania Ag. PEPCK-deficient parasites exhibited significantly greater extracellular acidification rate, increased proton leak, and decreased ATP-coupling efficiency and oxygen consumption rates in comparison with their wild-type and addback counterparts. Taken together, these results show that PEPCK is a critical metabolic enzyme for Leishmania, and its deletion results in altered metabolic activity and attenuation of virulence.


Assuntos
Leishmania major/metabolismo , Leishmania major/patogenicidade , Leishmaniose Cutânea/parasitologia , Fosfoenolpiruvato/metabolismo , Fatores de Virulência/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/parasitologia , Citocinas/imunologia , Feminino , Imunidade Celular/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Fosfoenolpiruvato/imunologia , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/metabolismo , Fatores de Virulência/imunologia
5.
J Immunol ; 206(3): 588-598, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33443083

RESUMO

Protective immunity to cutaneous leishmaniasis is mediated by IFN-γ-secreting CD4+ Th1 cells. IFN-γ binds to its receptor on Leishmania-infected macrophages, resulting in their activation, production of NO, and subsequent destruction of parasites. This study investigated the role of Semaphorin 3E (Sema3E) in host immunity to Leishmania major infection in mice. We observed a significant increase in Sema3E expression at the infection site at different timepoints following L. major infection. Sema3E-deficient (Sema3E knockout [KO]) mice were highly resistant to L. major infection, as evidenced by significantly (p < 0.05-0.01) reduced lesion sizes and lower parasite burdens at different times postinfection when compared with their infected wild-type counterpart mice. The enhanced resistance of Sema3E KO mice was associated with significantly (p < 0.05) increased IFN-γ production by CD4+ T cells. CD11c+ cells from Sema3E KO mice displayed increased expression of costimulatory molecules and IL-12p40 production following L. major infection and were more efficient at inducing the differentiation of Leishmania-specific CD4+ T cells to Th1 cells than their wild-type counterpart cells. Furthermore, purified CD4+ T cells from Sema3E KO mice showed increased propensity to differentiate into Th1 cells in vitro, and this was significantly inhibited by the addition of recombinant Sema3E in vitro. These findings collectively show that Sema3E is a negative regulator of protective CD4+ Th1 immunity in mice infected with L. major and suggest that its neutralization may be a potential therapeutic option for treating individuals suffering from cutaneous leishmaniasis.


Assuntos
Leishmania major/imunologia , Leishmaniose Cutânea/metabolismo , Semaforinas/metabolismo , Células Th1/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Humanos , Tolerância Imunológica , Leishmaniose Cutânea/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Semaforinas/genética
6.
PLoS Pathog ; 16(10): e1008994, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049000

RESUMO

Inflammation is critical for controlling pathogens, but also responsible for symptoms of infectious diseases. IL-27 is an important regulator of inflammation and can limit development of IFNγ-producing Tbet+ CD4+ T (Th1) cells. IL-27 is thought to do this by stimulating IL-10 production by CD4+ T cells, but the underlying mechanisms of these immunoregulatory pathways are not clear. Here we studied the role of IL-27 signalling in experimental visceral leishmaniasis (VL) caused by infection of C57BL/6 mice with the human pathogen Leishmania donovani. We found IL-27 signalling was critical for the development of IL-10-producing Th1 (Tr1) cells during infection. Furthermore, in the absence of IL-27 signalling, there was improved control of parasite growth, but accelerated splenic pathology characterised by the loss of marginal zone macrophages. Critically, we discovered that IL-27 signalling limited glycolysis in Th1 cells during infection that in turn attenuated inflammation. Furthermore, the modulation of glycolysis in the absence of IL-27 signalling restricted tissue pathology without compromising anti-parasitic immunity. Together, these findings identify a novel mechanism by which IL-27 mediates immune regulation during disease by regulating cellular metabolism.


Assuntos
Interleucinas/metabolismo , Leishmaniose Visceral/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Feminino , Glicólise , Interferon gama/imunologia , Interleucinas/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/imunologia , Baço/imunologia
7.
J Immunol ; 204(1): 128-136, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31776203

RESUMO

Semaphorin 3E (Sema3E) is a secreted protein that was initially discovered as a neuronal guidance cue. Recent evidence showed that Sema3E plays an essential role in regulating the activities of various immune cells. However, the exact role of Sema3E in macrophage function, particularly during inflammation, is not fully understood. We studied the impact of Sema3E gene deletion on macrophage function during the LPS-induced acute inflammatory response. We found that Sema3E-deficient (Sema3e-/- ) mice were better protected from LPS-induced acute inflammation as exemplified by their superior clinical score and effective temperature control compared with their wild-type littermates. This superior control of inflammatory response in Sema3e-/- mice was associated with significantly lower phosphorylation of ERK1/2, AKT, STAT3, and NF-κB, and a concomitant reduction in inducible NO synthase expression and production of TNF and IL-6 compared with their Sema3e+/+ littermates. Sema3e-/- mice also contained significantly higher numbers of activated macrophages compared with their Sema3e+/+ littermates at both baselines and after LPS challenge. In vivo-specific deletion of the Sema3E high-affinity receptor, plexinD1, on macrophages led to the improvement in clinical disease following exposure to a lethal dose of LPS. Collectively, our data show that Sema3E plays an essential role in dampening the early inflammatory response to LPS by regulating macrophage function, suggesting an essential role of this pathway in macrophage inflammatory response.


Assuntos
Inflamação/imunologia , Macrófagos/imunologia , Semaforinas/imunologia , Animais , Células Cultivadas , Inflamação/induzido quimicamente , Lipopolissacarídeos/administração & dosagem , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Semaforinas/deficiência
8.
J Immunol ; 205(5): 1355-1364, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32727889

RESUMO

There is currently no clinically effective vaccine against cutaneous leishmaniasis because of poor understanding of the Ags that elicit protective CD4+ T cell immunity. In this study, we identified a naturally processed peptide (DLD63-79) that is derived from Leishmania dihydrolipoyl dehydrogenase (DLD) protein. DLD is conserved in all pathogenic Leishmania species, is expressed by both the promastigote and amastigote stages of the parasite, and elicits strong CD4+ T cell responses in mice infected with L. major We generated I-Ab-DLD63-79 tetramer and identified DLD-specific CD4+ T cells at clonal level. Following L. major infection, DLD63-79-specific CD4+ T cells massively expanded and produced effector cytokines (IFN-γ and TNF). This was followed by a gradual contraction, stable maintenance following lesion resolution, and display of memory (recall) response following secondary challenge. Vaccination with rDLD protein induced strong protection in mice against virulent L. major challenge. Identification of Ags that elicit protective immunity and their responding Ag-specific T cells are critical steps necessary for developing effective vaccines and vaccination strategies against infectious agents, including protozoan parasites.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Di-Hidrolipoamida Desidrogenase/imunologia , Leishmania/imunologia , Animais , Linhagem Celular , Feminino , Interferon gama/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
9.
Afr J Reprod Health ; 26(12): 90-96, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37585089

RESUMO

Intrauterine adhesions (IUA) are rare. A retrospective comparative study was conducted between January 1, 2015, and December 31, 2018. Group A comprised 117 women who developed IUAs after open myomectomy, while Group B comprised 113 women who developed IUAs following uterine trauma caused by uterine instrumentation after a termination of pregnancy (TOP) or spontaneous miscarriage. The IUA grade and pregnancy rates and outcomes were compared using the March classification system. All patients underwent hysteroscopic adhesiolysis. The adhesions tended to be more severe (45/117, 38.5%) in Group A than in Group B (29/113, 25.7%); however, this difference was not statistically significant (Chi-Suare 5.047; p = .080). The period of observation was 24 months from the last hysteroscopy. The pregnancy rate in Group A (26, 22.2%) was significantly lower than in Group B (46, 40.7%) (OR: 2.403, 95% CI: 1.352-4.271; p = .003). Open myomectomy was the preceding aetiological factor in a greater proportion of women with IUA in our study. In cases where pregnancy is desired after open myomectomy, especially where the endometrial cavity is breached, postoperative hysteroscopy to exclude IUAs is recommended.


Assuntos
Doenças Uterinas , Miomectomia Uterina , Gravidez , Humanos , Feminino , Taxa de Gravidez , Miomectomia Uterina/efeitos adversos , Estudos Retrospectivos , Doenças Uterinas/cirurgia , Doenças Uterinas/complicações , Curetagem/efeitos adversos , Aderências Teciduais/etiologia , Aderências Teciduais/cirurgia
10.
J Immunol ; 203(4): 964-971, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31243088

RESUMO

NK cells are key innate immune cells that play critical roles in host defense. Although NK cells have been shown to regulate immunity to some infectious diseases, their role in immunity to Trypanosoma congolense has not been investigated. NK cells are vital sources of IFN-γ and TNF-α; two key cytokines that are known to play important roles in resistance to African trypanosomes. In this article, we show that infection with T. congolense leads to increased levels of activated and functional NK cells in multiple tissue compartments. Systemic depletion of NK cells with anti-NK1.1 mAb led to increased parasitemia, which was accompanied by significant reduction in IFN-γ production by immune cells in the spleens and liver of infected mice. Strikingly, infected NFIL3-/- mice (which genetically lack NK cell development and function) on the normally resistant background were highly susceptible to T. congolense infection. These mice developed fulminating and uncontrolled parasitemia and died significantly earlier (13 ± 1 d) than their wild-type control mice (106 ± 26 d). The enhanced susceptibility of NFIL3-/- mice to infection was accompanied by significantly impaired cytokine (IFN-γ and TNF-α) response by CD3+ T cells in the spleens and liver. Adoptive transfer of NK cells into NFIL3-/- mice before infection rescued them from acute death in a perforin-dependent manner. Collectively, these studies show that NK cells are critical for optimal resistance to T. congolense, and its deficiency leads to enhanced susceptibility in infected mice.


Assuntos
Células Matadoras Naturais/imunologia , Tripanossomíase Africana/imunologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Trypanosoma congolense/imunologia
11.
Palliat Support Care ; 19(2): 217-222, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32838822

RESUMO

OBJECTIVE: Palliative care providers may face questions from patients and relatives regarding the heritability of cancers. Implications of such discussions for providers have been little explored. This study aimed to gather palliative care providers' views on their main needs, roles, and ethical concerns regarding cancer family history discussions. METHOD: The palliative care providers who participated in the 2015 and 2017 annual meetings of the Quebec Palliative Care Association were approached to complete a web-based questionnaire. Study participants answered the questionnaire between November 2016 and July 2017. They were asked to identify the most facilitating factor for cancer family history discussions, as well as their most important knowledge needs, potential role, and ethical concerns. Descriptive analyses were conducted. RESULTS: Ninety-four palliative care providers answered the questionnaire. Access to specialized resources to obtain information and protocols or guidelines were considered the most facilitating factors for cancer family history discussions by 32% and 20% of providers, respectively. Knowledge of hereditary cancers was the most relevant educational need for 53%. Thirty-eight per cent considered essential to be informed about their rights and duties regarding cancer family history discussions. Being attentive to patients' concerns and referring families to appropriate resources were identified as the most relevant roles for palliative care providers by 47% and 34% of respondents, respectively. Fifty-eight per cent agreed that cancer family history discussions should be initiated only if beneficial to family members. SIGNIFICANCE OF RESULTS: Education on hereditary cancers made consensus among palliative care providers as the most important knowledge need regarding discussing cancer family history at the end of life. Nonetheless, other less commonly expressed needs, including access to genetics specialists, protocols, or guidelines, and awareness of provider rights and duties concerning such discussions, deserve attention. Answering providers' needs might help optimize cancer predisposition management in palliative care.


Assuntos
Anamnese , Neoplasias , Cuidados Paliativos , Morte , Família , Humanos , Neoplasias/genética , Inquéritos e Questionários
12.
Appl Environ Microbiol ; 86(5)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31836576

RESUMO

Despite glyphosate's wide use for weed control in agriculture, questions remain about the herbicide's effect on soil microbial communities. The existing scientific literature contains conflicting results, from no observable effect of glyphosate to the enrichment of agricultural pathogens such as Fusarium spp. We conducted a comprehensive field-based study to compare the microbial communities on the roots of plants that received a foliar application of glyphosate to adjacent plants that did not. The 2-year study was conducted in Beltsville, MD, and Stoneville, MS, with corn and soybean crops grown in a variety of organic and conventional farming systems. By sequencing environmental metabarcode amplicons, the prokaryotic and fungal communities were described, along with chemical and physical properties of the soil. Sections of corn and soybean roots were plated to screen for the presence of plant pathogens. Geography, farming system, and season were significant factors determining the composition of fungal and prokaryotic communities. Plots treated with glyphosate did not differ from untreated plots in overall microbial community composition after controlling for other factors. We did not detect an effect of glyphosate treatment on the relative abundance of organisms such as Fusarium spp.IMPORTANCE Increasing the efficiency of food production systems while reducing negative environmental effects remains a key societal challenge to successfully meet the needs of a growing global population. The herbicide glyphosate has become a nearly ubiquitous component of agricultural production across the globe, enabling an increasing adoption of no-till agriculture. Despite this widespread use, there remains considerable debate on the consequences of glyphosate exposure. In this paper, we examine the effect of glyphosate on soil microbial communities associated with the roots of glyphosate-resistant crops. Using metabarcoding techniques, we evaluated prokaryotic and fungal communities from agricultural soil samples (n = 768). No effects of glyphosate were found on soil microbial communities associated with glyphosate-resistant corn and soybean varieties across diverse farming systems.


Assuntos
Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Microbiota , Raízes de Plantas/microbiologia , Microbiologia do Solo , Glicina/administração & dosagem , Maryland , Microbiota/efeitos dos fármacos , Mississippi , Micobioma , Glycine max/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Glifosato
13.
Diabet Med ; 37(2): 211-218, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31613404

RESUMO

BACKGROUND: Diabetic foot ulcers portend an almost twofold increase in all-cause mortality compared with diabetes on its own. AIM: To investigate the association between diabetic foot ulcers and risk of death. METHODS: We performed a meta-analysis of all observational studies investigating the association between diabetic foot ulcers and all-cause mortality. Risk ratios and risk differences were pooled in a random-effects model. The I2 statistic was used to quantify heterogeneity between studies. RESULTS: Altogether, we identified 11 studies that reported 84 131 deaths from any cause in 446 916 participants with diabetes during a total of 643 499 person-years of follow-up. The crude event rate for all-cause mortality in individuals with diabetes who did not develop foot ulceration was 22% lower at 181.5 deaths (per 1000 person-years) than in those who developed foot ulcers (230.8 per 1000 person-years). Diabetic foot ulceration was associated with an increased risk of all-cause mortality (pooled relative risk 2.45, 95% CI 1.85-2.85). We did not observe any tangible differences in risk of all-cause mortality from diagnosis in studies reporting a mean duration of follow-up of ≤3 years (relative risk 2.43, 95% CI 2.27-2.61) or >3 years (relative risk 2.26, 95% CI 2.13-2.40) years. Funnel plot inspection revealed no significant publication bias among studies included in this meta-analysis. CONCLUSIONS: Our study shows an excess rate of all-cause mortality in people with diabetic foot ulceration when compared to those without foot ulceration. It is imperative that early interventions to prevent foot ulceration and modify cardiovascular disease risk factors are put in place to reduce excess mortality.


Assuntos
Diabetes Mellitus/epidemiologia , Pé Diabético/epidemiologia , Mortalidade , Causas de Morte , Humanos , Prognóstico
14.
J Immunol ; 201(11): 3362-3372, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30355785

RESUMO

The outcome of intracellular parasitic infection can be determined by the immunoregulatory activities of natural regulatory CD4+ Foxp3+ T (Treg) cells and the anti-inflammatory cytokine IL-10. These mechanisms protect tissue but can also suppress antiparasitic CD4+ T cell responses. The specific contribution of these regulatory pathways during human parasitic diseases remains unclear. In this study, we investigated the roles of Treg cells and IL-10 during experimental visceral leishmaniasis caused by Leishmania donovani infection of C57BL/6 mice. We report only a limited contribution of Treg cells in suppressing antiparasitic immunity, but important roles in delaying the development of splenic pathology and restricting leukocyte expansion. We next employed a range of cell-specific, IL-10- and IL-10R-deficient mice and found these Treg cell functions were independent of IL-10. Instead, conventional CD4+ T cells and dendritic cells were the most important cellular sources of IL-10, and the absence of IL-10 in either cell population resulted in greater control of parasite growth but also caused accelerated breakdown in splenic microarchitecture. We also found that T cells, dendritic cells, and other myeloid cells were the main IL-10-responding cells because in the absence of IL-10R expression by these cell populations, there was greater expansion of parasite-specific CD4+ T cell responses associated with improved control of parasite growth. Again, however, there was also an accelerated breakdown in splenic microarchitecture in these animals. Together, these findings identify distinct, cell-specific, immunoregulatory networks established during experimental visceral leishmaniasis that could be manipulated for clinical advantage.


Assuntos
Interleucina-10/metabolismo , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , Baço/imunologia , Linfócitos T Reguladores/imunologia , Animais , Antígenos CD4/metabolismo , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunomodulação , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais
15.
Exp Parasitol ; 216: 107940, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32562606

RESUMO

Therapeutic options for the treatment of leishmaniasis are insufficient and need improvements owing to their low efficiency and high toxicity as well as the emergence of resistant strains. The limited number of new drugs for neglected diseases and lack of innovation in your development are still challenges. In this context, the process of discovery and development of biological assays play a pivotal role for the identification of bioactive compounds. The assays currently used for screening of drugs with cytotoxic activity against Leishmania parasites, include different processes that utilize intact parasite (free or intracellular) or specific enzymes of metabolism as a target cell. These assays allow the screening of large numbers of samples followed by more detailed secondary confirmatory assays to confirm the observed activity and assess their toxicity. In the present study, we described the development of a new functional and more complete assay that enables simultaneous assessment of potential anti-Leishmania compounds through evaluation of internalization of fluorescein-labeled L. braziliensis promastigotes by human peripheral blood monocytes and their cytotoxicity by flow cytometry. We standardized the conditions for parasite labeling to achieve better phagocytosis analysis by setting the ratio of number of parasites per cell as 1 to 2, at incubation time of 6h. The cytotoxicity assessment was performed by the quantification of cells undergoing early/late apoptosis and necrosis using a double labelling platform employing 7AAD for late apoptosis and necrosis analysis and Annexin-V for early apoptosis evaluation. Hemolysis analysis was an additional parameter to test cytotoxicity. Two drugs used on clinic (Amphotericin B and Glucantime®) were used to validate the proposed methodology, and the assay was able to detect their known leishmanicidal activity and immunotoxicity properties. This new predictive assay will contribute to the development of translational medicine strategies in drug discovery for neglected diseases such as leishmaniasis.


Assuntos
Alternativas aos Testes com Animais/métodos , Antiprotozoários/toxicidade , Citometria de Fluxo/métodos , Leishmania/efeitos dos fármacos , Doenças Negligenciadas/tratamento farmacológico , Adulto , Anfotericina B/farmacologia , Anfotericina B/toxicidade , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Humanos , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Leucócitos/parasitologia , Antimoniato de Meglumina/farmacologia , Antimoniato de Meglumina/uso terapêutico , Antimoniato de Meglumina/toxicidade , Microscopia Confocal , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/parasitologia , Fatores de Tempo , Adulto Jovem
16.
Afr J Reprod Health ; 24(2): 123-128, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34077098

RESUMO

The effect of endometrial thickness on in vitro fertilization (IVF) outcome is still a subject of debate. It is unclear why a thin endometrium reduces IVF success rates. Our objective was to analyze the hysteroscopic findings in women scheduled for IVF who had an endometrial thickness less than 7 mm. Relevant data of patients scheduled for IVF cycles and found to have an endometrial thickness (ET) of <7 mm on transvaginal ultrasound scan (TVS) between April 1, 2010 and March 31, 2017, at a private fertility and minimal access surgery unit in the Niger-Delta region of Nigeria, were retrieved and documented. A total of 41 patients had ET <7 mm during the study period. These patients accounted for 2.8% of the 1487 IVF cycles performed during the same period. All 41 patients had office hysteroscopies performed, constituting 4.1% of the 1,002 hysteroscopies performed during the study period. The age range of the patients was 23 - 50 years with a mean of 39.9 ± 6.9 years, and the duration of infertility ranged from 3 to 13 years with a mean of 7.2 ± 2.5 years. Most of the patients (32, 78.1%) had secondary infertility. Sixteen patients (39.0%) had intrauterine adhesions. A thin endometrium, though infrequent during IVF treatment cycles, might be associated with undiagnosed intrauterine adhesions.


Assuntos
Endométrio/patologia , Fertilização in vitro , Histeroscopia/métodos , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/terapia , Pólipos/cirurgia , Aderências Teciduais/cirurgia , Adulto , Feminino , Humanos , Histeroscopia/estatística & dados numéricos , Incidência , Nigéria , Pólipos/patologia , Gravidez , Estudos Retrospectivos , Aderências Teciduais/patologia , Resultado do Tratamento , Adulto Jovem
17.
Cytokine ; 124: 154542, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30241896

RESUMO

In their quiescent state, Hepatic stellate cells (HSCs), are present in the sub-endothelial space of Disse and have minimal interaction with immune cells. However, upon activation following injury, HSCs directly or indirectly interact with various immune cells that enter the space of Disse and thereby regulate diverse hepatic function and immune physiology. Other than the normal physiological functions of HSCs such as hepatic homeostasis, maturation and differentiation, they also participate in hepatic inflammation by releasing a battery of inflammatory cytokines and chemokines and interacting with other liver cells. Here, we have reviewed the role of HSC in the pathogenesis of liver inflammation and some infectious diseases in order to understand how the interplay between immune cells and HSCs regulates the overall outcome and disease pathology.


Assuntos
Quimiocinas/metabolismo , Citocinas/metabolismo , Células Estreladas do Fígado/imunologia , Fígado/imunologia , Animais , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Hepatite/imunologia , Hepatite/metabolismo , Hepatite/virologia , Humanos , Fígado/microbiologia , Fígado/patologia , Fígado/virologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/metabolismo
18.
Diabet Med ; 36(9): 1133-1140, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31077439

RESUMO

AIM: To assess the impact of autologous cell therapy on critical limb ischaemia in people with diabetes and diabetic kidney disease. METHODS: A total of 59 people with diabetes (type 1 or type 2) and critical limb ischaemia, persisting after standard revascularization, were treated with cell therapy in our foot clinic over 7 years; this group comprised 17 people with and 42 without severe diabetic kidney disease. The control group had the same inclusion criteria, but was treated conservatively and comprised 21 people with and 23 without severe diabetic kidney disease. Severe diabetic kidney disease was defined as chronic kidney disease stages 4-5 (GFR <30 ml/min/1.73 m²). Death and amputation-free survival were assessed during the 18-month follow-up; changes in transcutaneous oxygen pressure were evaluated at 6 and 12 months after cell therapy. RESULTS: Transcutaneous oxygen pressure increased significantly in both groups receiving cell therapy compared to baseline (both P<0.01); no significant change in either of the control groups was observed. The cell therapy severe diabetic kidney disease group had a significantly longer amputation-free survival time compared to the severe diabetic kidney disease control group (hazard ratio 0.36, 95% CI 0.14-0.91; P=0.042); there was no difference in the non-severe diabetic kidney disease groups. The severe diabetic kidney disease control group had a tendency to have higher mortality (hazard ratio 2.82, 95% CI 0.81-9.80; P=0.062) than the non-severe diabetic kidney disease control group, but there was no difference between the severe diabetic kidney disease and non-severe diabetic kidney disease cell therapy groups. CONCLUSIONS: The present study shows that autologous cell therapy in people with severe diabetic kidney disease significantly improved critical limb ischaemia and lengthened amputation-free survival in comparison with conservative treatment; however, the treatment did not influence overall survival.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Pé Diabético/terapia , Nefropatias Diabéticas/complicações , Pé/irrigação sanguínea , Isquemia/terapia , Salvamento de Membro/métodos , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Estudos de Casos e Controles , Estado Terminal/epidemiologia , Estado Terminal/terapia , República Tcheca/epidemiologia , Pé Diabético/complicações , Pé Diabético/epidemiologia , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/terapia , Feminino , Seguimentos , Pé/patologia , Humanos , Isquemia/complicações , Isquemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Transplante Autólogo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodos
19.
Diabet Med ; 36(11): 1412-1416, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30320946

RESUMO

AIM: To determine how routinely collected data can inform a risk model to predict de novo foot ulcer presentation in the primary care setting. METHODS: Data were available on 15 727 individuals without foot ulcers and 1125 individuals with new foot ulcers over a 12-year follow-up in UK primary care. We examined known risk factors and added putative risk factors in our logistic model. RESULTS: People with foot ulcers were 4.2 years older (95% CI 3.1-5.2) than those without, and had higher HbA1c % (mean 7.9 ± 1.9 vs 7.5 ± 1.7) / HbA1c mmol/mol (63 ± 21 vs 59 ± 19) (p<0.0001) concentration [+0.45 (95% CI 0.33-0.56), creatinine level [+6.9 µmol/L (95% CI 4.1-9.8)] and Townsend score [+0.055 (95% CI 0.033-0.077)]. Absence of monofilament sensation was more common in people with foot ulcers (28% vs 21%; P<0.0001), as was absence of foot pulses (6.4% vs 4.8%; P=0.017). There was no difference between people with or without foot ulcers in smoking status, gender, history of stroke or foot deformity, although foot deformity was extremely rare (0.4% in people with foot ulcers, 0.6% in people without foot ulcers). Combining risk factors in a single logistic regression model gave modest predictive power, with an area under the receiver-operating characteristic curve of 0.65 (95% CI 0.62-0.67). The prevalence of ulceration in the bottom decile of risk was 1.8% and in the top decile it was 13.4% (compared with an overall prevalence of 6.5%); thus, the presence of all six risk factors gave a relative risk of 7.4 for development of a foot ulcer over 12 years. CONCLUSION: We have made some progress towards defining a variable set that can be used to create a foot ulcer prediction model. More accurate determination of foot deformity/pedal circulation in primary care may improve the predictive value of such a future risk model, as will identification of additional risk variables.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Registros Eletrônicos de Saúde/estatística & dados numéricos , Úlcera do Pé/diagnóstico , Atenção Primária à Saúde , Transtornos de Sensação/fisiopatologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Creatinina/sangue , Coleta de Dados , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Úlcera do Pé/epidemiologia , Úlcera do Pé/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Autocuidado , Transtornos de Sensação/epidemiologia , Transtornos de Sensação/etiologia , Fumar , Reino Unido/epidemiologia , Adulto Jovem
20.
J Immunol ; 199(3): 1086-1095, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28659355

RESUMO

Despite decades of clinical and biomedical research, the pathogenesis of sepsis and its spectrum of diseases (severe sepsis and septic shock), which are leading causes of death in intensive care units, are still poorly understood. In this article, we show that signaling via the p110δ isoform of PI3K is critical for survival in experimental sepsis. Mice with an inactive knock-in mutation in the p110δ gene (p110δD910A) succumbed acutely to nonlethal dose LPS challenge. The susceptibility of p110δD910A mice to LPS was associated with increased neutrophil numbers and activities in the tissues, due in part to delayed apoptosis resulting mostly from inherent reduced regulatory T cell (Treg) numbers. Adoptive transfer of wild-type or p110δD910A Tregs abrogated exaggerated neutrophil activity, increased neutrophil apoptosis, and rescued p110δD910A mice from mortality after LPS challenge. We confirmed the clinical relevance of these findings by showing that human Tregs also regulate neutrophil function and survival. Collectively, our results show that PI3K δ is essential for survival during sepsis. In addition, our data highlight the importance of Tregs in regulating the pathogenesis of sepsis and septic shock via their effects on neutrophil survival and function, and provide evidence of regulation of innate immunity by cells of the adaptive immune system.


Assuntos
Neutrófilos/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Sepse/imunologia , Choque Séptico/mortalidade , Linfócitos T Reguladores/imunologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células/genética , Proliferação de Células/fisiologia , Classe I de Fosfatidilinositol 3-Quinases , Técnicas de Introdução de Genes , Imunidade Inata , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/imunologia , Ativação Linfocitária , Camundongos , Neutrófilos/patologia , Neutrófilos/fisiologia , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Isoformas de Proteínas , Sepse/fisiopatologia , Choque Séptico/imunologia , Choque Séptico/fisiopatologia , Transdução de Sinais
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