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1.
Mediators Inflamm ; 2020: 6914878, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061829

RESUMO

Background: COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has threatened every civilian as a global pandemic. The immune system poses the critical interactive chain between the human body and the virus. Here, we make efforts to examine whether comorbidity with type 2 diabetes (T2D) affects the immunological response in COVID-19 patients. Methods: We conducted a retrospective pilot study investigating immunological characteristics of confirmed cases of COVID-19 with or without comorbid T2D. Two subcohorts of sex- and age-matched participants were eligible for data analysis, of which 33 participants were with T2D and the remaining 37 were nondiabetic (NDM). Cellular immunity was assessed by flow cytometric determination of surface markers including CD3, CD4, CD8, CD19, CD16, and CD56 in peripheral blood. Levels of C reactive protein, immunoglobulin (IgG, IgM, IgA, and IgE), and complements (C3, C4) were detected by rate nephelometry immunoassay. And Th1/Th2 cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) were detected by Cytometric Bead Array. Results: Neutrophil counts were found to be significantly higher in the T2D group than in the NDM group and had a significant relevance with clinical severity. Lymphocyte frequencies showed no significant differences in the two groups. However, the proportions and absolute counts of T, Tc, Th, and NK cells decreased in both groups to different degrees. An abnormal increase in neutrophil count and a decrease in lymphocyte subpopulations may represent risk factors of COVID-19 severity. The level of IgG, IgM, IgA, C3, and C4 showed no significant difference between the two groups, while the IgE levels were higher in the T2D group than in the NDM group (p < 0.05). Th1 cytokines including IFN-γ, TNF-α, and IL-6, as well as CRP, appeared significantly higher in the T2D group. Conclusions: The COVID-19 patients comorbid with T2D demonstrated distinguishable immunological parameters, which represented clinical relevancies with the predisposed disease severity in T2D.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Diabetes Mellitus Tipo 2/imunologia , Pneumonia Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Comorbidade , Proteínas do Sistema Complemento/metabolismo , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Citocinas/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Imunidade Celular , Imunoglobulinas/sangue , Mediadores da Inflamação/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Projetos Piloto , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Células Th1/imunologia , Células Th2/imunologia
2.
APMIS ; 128(11): 593-602, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32870528

RESUMO

Induction of broad Th1 cellular immune responses and cytokines is crucial characteristics for vaccines against intracellular infections such as hepatitis C virus (HCV). Plants (especially oilseed tissues) and plant-immunomodulators (like oil bodies) offer cost-effective and scalable possibilities for the production of immunologically relevant and safe vaccine antigens and adjuvants, respectively. Herein, we provide data of the murine immunization by transgenic canola oilseed-derived HCV core protein (HCVcp) soluble extract (TSE) and Escherichia coli- derived rHCVcp in combination with Canola oil bodies (oil) compared to that of the Freund's (FA) adjuvant. Mice immunized by TSE+ oil developed both strong humeral (IgG) and Th1-biased cellular responses, manifested by high levels of IFN-γ and lower IgG1/IgG2a ratio and IL-4 secretion. Results of the intracellular cytokine staining indicated that TSE+ oil immunization in mice triggered both CD4+ and CD8+ T cells to release IFN-γ, while CD4+ cells were mostly triggered when FA was used. Analyses by qRT-PCR indicated that a combination of rHCVcp/TSE with oil body induced high levels of IL-10 cytokines compared to that of the FA adjuvant. These characteristics are important properties for the design of an HCV vaccine candidate and indicate the potential of Canola-derived antigen and oil bodies in addressing these concerns.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/prevenção & controle , Proteínas Recombinantes/administração & dosagem , Células Th1/efeitos dos fármacos , Proteínas do Core Viral/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Imunidade Celular/efeitos dos fármacos , Imunoglobulina G/biossíntese , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Óleo de Brassica napus/administração & dosagem , Óleo de Brassica napus/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Células Th1/imunologia , Células Th1/virologia , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/imunologia , Vacinas contra Hepatite Viral/biossíntese
3.
Front Immunol ; 11: 2056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973814

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19), a disease which causes severe lung injury and multiple organ damage, presents an urgent need for new drugs. The case severity and fatality of COVID-19 are associated with excessive inflammation, namely, a cytokine storm. Metformin, a widely used drug to treat type 2 diabetes (T2D) mellitus and metabolic syndrome, has immunomodulatory activity that reduces the production of proinflammatory cytokines using macrophages and causes the formation of neutrophil extracellular traps (NETs). Metformin also inhibits the cytokine production of pathogenic Th1 and Th17 cells. Importantly, treatment with metformin alleviates various lung injuries in preclinical animal models. In addition, a recent proteomic study revealed that metformin has the potential to directly inhibit SARS-CoV-2 infection. Furthermore, retrospective clinical studies have revealed that metformin treatment reduces the mortality of T2D with COVID-19. Therefore, metformin has the potential to be repurposed to treat patients with COVID-19 at risk of developing severe illness. This review summarizes the immune pathogenesis of SARS-CoV-2 and addresses the effects of metformin on inhibiting cytokine storms and preventing SARS-CoV-2 infection, as well as its side effects.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Lesão Pulmonar/tratamento farmacológico , Metformina/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Animais , Antivirais/efeitos adversos , Antivirais/farmacologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Citocinas/antagonistas & inibidores , Reposicionamento de Medicamentos/métodos , Armadilhas Extracelulares/efeitos dos fármacos , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/farmacologia , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Metformina/efeitos adversos , Metformina/farmacologia , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia
4.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
5.
PLoS Pathog ; 16(8): e1008733, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817694

RESUMO

Staphylococcus aureus (S. aureus) is one of the most common bacterial infections worldwide, and antibiotic resistant strains such as Methicillin-Resistant S. aureus (MRSA) are a major threat and burden to public health. MRSA not only infects immunocompromised patients but also healthy individuals and has rapidly spread from the healthcare setting to the outside community. However, all vaccines tested in clinical trials to date have failed. Immunocompromised individuals such as patients with HIV or decreased levels of CD4+ T cells are highly susceptible to S. aureus infections, and they are also at increased risk of developing fungal infections. We therefore wondered whether stimulation of antifungal immunity might promote the type of immune responses needed for effective host defense against S. aureus. Here we show that vaccination of mice with a fungal ß-glucan particle (GP) loaded with S. aureus antigens provides protective immunity to S. aureus. We generated glucan particles loaded with the four S. aureus proteins ClfA, IsdA, MntC, and SdrE, creating the 4X-SA-GP vaccine. Vaccination of mice with three doses of 4X-SA-GP promoted protection in a systemic model of S. aureus infection with a significant reduction in the bacterial burden in the spleen and kidneys. 4X-SA-GP vaccination induced antigen-specific Th1 and Th17 CD4+ T cell and antibody responses and provided long-term protection. This work suggests that the GP vaccine system has potential as a novel approach to developing vaccines for S. aureus.


Assuntos
Saccharomyces cerevisiae/imunologia , Infecções Estafilocócicas/imunologia , Vacinas Antiestafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Coagulase/administração & dosagem , Coagulase/genética , Coagulase/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Saccharomyces cerevisiae/química , Infecções Estafilocócicas/microbiologia , Vacinas Antiestafilocócicas/administração & dosagem , Vacinas Antiestafilocócicas/genética , Staphylococcus aureus/genética , Células Th1/imunologia , Células Th17/imunologia , Vacinação , beta-Glucanas/administração & dosagem , beta-Glucanas/imunologia
6.
Eur J Endocrinol ; 183(5): R133-R147, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32755992

RESUMO

The SARS-CoV-2 virus responsible for the COVID-19 pandemic has generated an explosion of interest both in the mechanisms of infection leading to dissemination and expression of this disease, and in potential risk factors that may have a mechanistic basis for disease propagation or control. Vitamin D has emerged as a factor that may be involved in these two areas. The focus of this article is to apply our current understanding of vitamin D as a facilitator of immunocompetence both with regard to innate and adaptive immunity and to consider how this may relate to COVID-19 disease. There are also intriguing potential links to vitamin D as a factor in the cytokine storm that portends some of the most serious consequences of SARS-CoV-2 infection, such as the acute respiratory distress syndrome. Moreover, cardiac and coagulopathic features of COVID-19 disease deserve attention as they may also be related to vitamin D. Finally, we review the current clinical data associating vitamin D with SARS-CoV-2 infection, a putative clinical link that at this time must still be considered hypothetical.


Assuntos
Imunidade Adaptativa/imunologia , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Imunidade Inata/imunologia , Imunocompetência/imunologia , Pulmão/imunologia , Pneumonia Viral/imunologia , Linfócitos T/imunologia , Vitamina D/imunologia , Peptídeos Catiônicos Antimicrobianos/imunologia , Autofagia/imunologia , Betacoronavirus , Defensinas/imunologia , Humanos , Pandemias , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Vitamina D/análogos & derivados
7.
Exp Parasitol ; 216: 107944, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32619431

RESUMO

Evaluation of the murine isotype antibodies is essential in subunit vaccine development because inbred mouse strains with diverse genetic backgrounds respond different to recombinant proteins. In this regard, the main goal of this study was to measuring and comparing the profile of IgG isotype responses in C57BL/6 mice. For this purpose, the extracellular region of plasmodium vivax thrombospondin-related adhesive protein (PvTRAP) gene was expressed in Escherichia coli Rosetta (DE3)-pET23a. Then, the recombinant PvTRAP alone or emulsified with Freund's complete adjuvant were applied for immunization of the C57BL/6 mice. The role of antibodies and cellular immune responses induced by recombinant PvTRAP were evaluated. The results showed the level of anti-rPvTRAP IgG2c was significantly higher than IgG2a in the groups that received rPvTRAP alone (mean OD490 = 0.798 ± 0.12 and 0.39 ± 0.1, respectively) and emulsified with CFA/IFA (mean OD490 = 1.48 ± 0.07 and 0.605 ± 0.13, respectively; P < 0.05, independent sample t-test). Additionally, the immunized mice with rPvTRAP and rPvTRAP + CFA/IFA had an intermediate-avidity IgG2a antibody but high-avidity IgG2c antibody as well as the mean of serum antibody titers results exhibited that in both rPvTRAP and rPvTRAP + CFA/IFA mouse groups, IgG2a end-point titer (1:3200 and 1:25,600, respectively) was noteworthy lower than IgG2c (1:25,600 and 1:102,400, respectively). Moreover, the results revealed the eliciting significant levels of IFN-γ (P < 0.05, independent sample t-test) and no detectable level of IL-4 in the mouse groups received rPvTRAP alone and emulsified with CFA/IFA as compared to the mouse control groups. In general, our results showed that for correctly interpreting of Th1 immune responses in C57BL/6 mouse strain it is critical to measure IgG2c instead of IgG2a along with IFN-γ.


Assuntos
Imunoglobulina G/sangue , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Células Th1/imunologia , Células Th2/imunologia , Animais , Afinidade de Anticorpos , Dicroísmo Circular , Feminino , Imunofluorescência , Imunoglobulina G/classificação , Interferon gama/análise , Interleucina-4/análise , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/imunologia , Vacinas de Subunidades/imunologia , Vacinas Sintéticas/imunologia
8.
Nat Commun ; 11(1): 3366, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632165

RESUMO

CD4+ T lymphocytes consist of naïve, antigen-specific memory, and memory-phenotype (MP) cell compartments at homeostasis. We recently showed that MP cells exert innate-like effector function during host defense, but whether MP CD4+ T cells are functionally heterogeneous and, if so, what signals specify the differentiation of MP cell subpopulations under homeostatic conditions is still unclear. Here we characterize MP lymphocytes as consisting of T-bethigh, T-betlow, and T-bet- subsets, with innate, Th1-like effector activity exclusively associated with T-bethigh cells. We further show that the latter population depends on IL-12 produced by CD8α+ type 1 dendritic cells (DC1) for its differentiation. Finally, our data demonstrate that this tonic IL-12 production requires TLR-MyD88 signaling independent of foreign agonists, and is further enhanced by CD40-CD40L interactions between DC1 and CD4+ T lymphocytes. We propose that optimal differentiation of T-bethigh MP lymphocytes at homeostasis is driven by self-recognition signals at both the DC and Tcell levels.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Homeostase/imunologia , Memória Imunológica/imunologia , Proteínas com Domínio T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Ligante de CD40/genética , Ligante de CD40/imunologia , Ligante de CD40/metabolismo , Antígenos CD8/imunologia , Antígenos CD8/metabolismo , Comunicação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-12/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Transdução de Sinais/imunologia , Proteínas com Domínio T/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo
9.
Nat Commun ; 11(1): 3421, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647184

RESUMO

The OX40-OX40L pathway provides crucial co-stimulatory signals for CD4 T cell responses, however the precise cellular interactions critical for OX40L provision in vivo and when these occur, remains unclear. Here, we demonstrate that provision of OX40L by dendritic cells (DCs), but not T cells, B cells nor group 3 innate lymphoid cells (ILC3s), is critical specifically for the effector Th1 response to an acute systemic infection with Listeria monocytogenes (Lm). OX40L expression by DCs is regulated by cross-talk with NK cells, with IFNγ signalling to the DC to enhance OX40L in a mechanism conserved in both mouse and human DCs. Strikingly, DC expression of OX40L is redundant in a chronic intestinal Th1 response and expression by ILC3s is necessary. Collectively these data reveal tissue specific compartmentalisation of the cellular provision of OX40L and define a mechanism controlling DC expression of OX40L in vivo.


Assuntos
Microambiente Celular , Ligante OX40/metabolismo , Células Th1/imunologia , Animais , Comunicação Celular , Sinais (Psicologia) , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Humanos , Interferon gama/biossíntese , Interleucina-12/farmacologia , Intestinos/citologia , Antígeno Ki-1/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Listeria monocytogenes/fisiologia , Camundongos Endogâmicos C57BL , Receptores CXCR5/metabolismo , Receptores OX40/metabolismo , Baço/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
PLoS Comput Biol ; 16(7): e1008051, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32730250

RESUMO

In the animal kingdom, various forms of swarming enable groups of autonomous individuals to transform uncertain information into unified decisions which are probabilistically beneficial. Crossing scales from individual to group decisions requires dynamically accumulating signals among individuals. In striking parallel, the mammalian immune system is also a group of decentralized autonomous units (i.e. cells) which collectively navigate uncertainty with the help of dynamically accumulating signals (i.e. cytokines). Therefore, we apply techniques of understanding swarm behavior to a decision-making problem in the mammalian immune system, namely effector choice among CD4+ T helper (Th) cells. We find that incorporating dynamic cytokine signaling into a simple model of Th differentiation comprehensively explains divergent observations of this process. The plasticity and heterogeneity of individual Th cells, the tunable mixtures of effector types that can be generated in vitro, and the polarized yet updateable group effector commitment often observed in vivo are all explained by the same set of underlying molecular rules. These rules reveal that Th cells harness dynamic cytokine signaling to implement a system of quorum sensing. Quorum sensing, in turn, may confer adaptive advantages on the mammalian immune system, especially during coinfection and during coevolution with manipulative parasites. This highlights a new way of understanding the mammalian immune system as a cellular swarm, and it underscores the power of collectives throughout nature.


Assuntos
Percepção de Quorum , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Diferenciação Celular , Citocinas/imunologia , Tomada de Decisões , Humanos , Sistema Imunitário , Interferon gama/imunologia , Ativação Linfocitária , Modelos Teóricos , Probabilidade , Transdução de Sinais , Processos Estocásticos , Linfócitos T Auxiliares-Indutores/citologia , Células Th1/citologia , Células Th1/imunologia , Células Th2/citologia , Células Th2/imunologia
11.
Med Hypotheses ; 143: 110087, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32679426

RESUMO

COVID-19 is a major public health issue around the world and new data about its etiological agent, SARS-CoV-2, are urgently necessary, also translating the scientific knowledge acquired on its more similar predecessors, SARS-CoV-1 and MERS-CoV, the coronaviruses responsible for SARS and MERS, respectively. Like SARS-CoV-1, SARS-CoV-2 exploits the ACE2 receptors to enter the host cells; nevertheless, recent bioinformatics insights suggest a potential interaction of SARS-CoV-2 with the «moonlighting protein¼ CD26/DPP4, exactly how MERS-CoV works. CD26/DPP4 is overexpressed on T-helper type 1 (Th1) cells and its expression increases with aging, all factors which could well explain the Th1 immune lockdown, especially in the elderly, during fatal SARS-CoV-2 infections. Facing with this scenario, it is possible that Th1 and T-cytotoxic lymphocytes are the immune cells most affected by SARS-CoV-2, and that the immune system is forced to mount a T-helper type 2 (Th2) response, the only one still mountable, in the attempt to counteract the viral load. However, in this way, the symptomatic patient experiences all the negative effects of the Th2 response, which can seriously aggravate the clinical picture.


Assuntos
Infecções por Coronavirus/imunologia , Dipeptidil Peptidase 4/imunologia , Pneumonia Viral/imunologia , Células Th1/imunologia , Adulto , Idoso , Autopsia , Betacoronavirus , Biologia Computacional , Regulação da Expressão Gênica , Humanos , Sistema Imunitário , Itália , Masculino , Pessoa de Meia-Idade , Pandemias , Ligação Proteica , Linfócitos T Citotóxicos/virologia , Células Th1/virologia
12.
PLoS Negl Trop Dis ; 14(6): e0008386, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32542003

RESUMO

Chromoblastomycosis (CBM) is a chronic worldwide subcutaneous mycosis, caused by several dimorphic, pigmented dematiaceous fungi. It is difficult to treat patients with the disease, mainly because of its recalcitrant nature. The correct activation of host immune response is critical to avoid fungal persistence in the tissue and disease chronification. CD4+ T cells are crucial for the development of protective immunity to F. pedrosoi infection. Here, we investigated T helper cell response dynamics during experimental CBM. Following footpad injection with F. pedrosoi hyphae and conidia, T cells were skewed towards a Th17 and Th1 phenotype. The Th17 population was the main Th cell subset found in the infected area during the early stages of experimental murine CBM, followed by Th1 predominance in the later stages, coinciding with the remission phase of the disease in this experimental model. Depletion of CD25+ cells, which leads to a reduction of Treg cells in the draining lymph node, resulted in decline in fungal burden after 14 days of infection. However, fungal cells were not cleared in the later stages of the disease, prolonging CBM clinical features in those animals. IL-17A and IFN-γ neutralization hindered fungal cell elimination in the course of the disease. Similarly, in dectin-2 KO animals, Th17 contraction in the course of experimental CBM was accompanied by fungal burden decrease in the first 14 days of infection, although it did not affect disease resolution. In this study, we gained insight into T helper subsets' dynamics following footpad injections of F. pedrosoi propagules and uncovered their contribution to disease resolution. The Th17 population proved to be important in eliminating fungal cells in the early stages of infection. The Th1 population, in turn, closely assisted by Treg cells, proved to be relevant not only in the elimination of fungal cells at the beginning of infection but also essential for their complete elimination in later stages of the disease in a mouse experimental model of CBM.


Assuntos
Ascomicetos/imunologia , Cromoblastomicose/imunologia , Lectinas Tipo C/metabolismo , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Cromoblastomicose/microbiologia , Cromoblastomicose/patologia , Modelos Animais de Doenças , Humanos , Hifas , Interferon gama/metabolismo , Interleucina-17/metabolismo , Lectinas Tipo C/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Esporos Fúngicos
13.
Parasitol Res ; 119(8): 2609-2622, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32535734

RESUMO

The treatment against visceral leishmaniasis (VL) presents problems, mainly related to the toxicity and/or high cost of the drugs. In this context, a prophylactic vaccination is urgently required. In the present study, a Leishmania protein called LiHyE, which was suggested recently as an antigenic marker for canine and human VL, was evaluated regarding its immunogenicity and protective efficacy in BALB/c mice against Leishmania infantum infection. In addition, the protein was used to stimulate peripheral blood mononuclear cells (PBMCs) from VL patients before and after treatment, as well as from healthy subjects. Vaccination results showed that the recombinant (rLiHyE) protein associated with liposome or saponin induced effective protection in the mice, since significant reductions in the parasite load in spleen, liver, draining lymph nodes, and bone marrow were found. The parasitological protection was associated with Th1-type cell response, since high IFN-γ, IL-12, and GM-CSF levels, in addition to low IL-4 and IL-10 production, were found. Liposome induced a better parasitological and immunological protection than did saponin. Experiments using PBMCs showed rLiHyE-stimulated lymphoproliferation in treated patients' and healthy subjects' cells, as well as high IFN-γ levels in the cell supernatant. In conclusion, rLiHyE could be considered for future studies as a vaccine candidate against VL.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Protozoários/administração & dosagem , Leishmania infantum/imunologia , Leishmaniose Visceral/prevenção & controle , Animais , Antígenos de Protozoários/imunologia , Feminino , Humanos , Imunogenicidade da Vacina , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Células Th1/imunologia , Vacinação
14.
PLoS Negl Trop Dis ; 14(6): e0008069, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32498074

RESUMO

Africa is the second most populous continent and has perennial health challenges. Of the estimated 181 million school aged children in sub-Saharan Africa (SSA), nearly half suffer from ascariasis, trichuriasis, or a combination of these infections. Coupled with these is the problem of tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) infection, which is a leading cause of death in the region. Compared to the effect of the human immunodeficiency virus on the development of TB, the effect of chronic helminth infections is a neglected area of research, yet helminth infections are as ubiquitous as they are varied and may potentially have profound effects upon host immunity, particularly as it relates to TB infection, diagnosis, and vaccination. Protection against active TB is known to require a clearly delineated T-helper type 1 (Th1) response, while helminths induce a strong opposing Th2 and immune-regulatory host response. This Review highlights the potential challenges of helminth-TB co-infection in Africa and the need for further research.


Assuntos
Ascaríase/epidemiologia , Coinfecção/epidemiologia , Tricuríase/epidemiologia , Vacinas contra a Tuberculose/imunologia , Tuberculose/complicações , Tuberculose/epidemiologia , Adolescente , África/epidemiologia , Ascaríase/complicações , Ascaríase/imunologia , Criança , Pré-Escolar , Coinfecção/imunologia , Coinfecção/prevenção & controle , Feminino , Humanos , Lactente , Masculino , Prevalência , Células Th1/imunologia , Células Th2/imunologia , Tricuríase/complicações , Tricuríase/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinas contra a Tuberculose/administração & dosagem
15.
N Engl J Med ; 382(24): 2337-2343, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32521134

RESUMO

We describe a case of life-threatening disseminated coccidioidomycosis in a previously healthy child. Like most patients with disseminated coccidioidomycosis, this child had no genomic evidence of any known, rare immune disease. However, comprehensive immunologic testing showed exaggerated production of interleukin-4 and reduced production of interferon-γ. Supplementation of antifungal agents with interferon-γ treatment slowed disease progression, and the addition of interleukin-4 and interleukin-13 blockade with dupilumab resulted in rapid resolution of the patient's clinical symptoms. This report shows that blocking of type 2 immune responses can treat infection. This immunomodulatory approach could be used to enhance immune clearance of refractory fungal, mycobacterial, and viral infections. (Supported by the Jeffrey Modell Foundation and the National Institutes of Health.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antifúngicos/uso terapêutico , Coccidioidomicose/tratamento farmacológico , Interferon gama/uso terapêutico , Encéfalo/diagnóstico por imagem , Pré-Escolar , Coccidioidomicose/imunologia , Progressão da Doença , Quimioterapia Combinada , Humanos , Interferon gama/metabolismo , Interleucina-12/metabolismo , Interleucina-13/antagonistas & inibidores , Interleucina-4/antagonistas & inibidores , Interleucina-4/metabolismo , Imagem por Ressonância Magnética , Masculino , Isoformas de Proteínas , Receptores de Interleucina-12/química , Receptores de Interleucina-12/genética , Coluna Vertebral/diagnóstico por imagem , Células Th1/imunologia
16.
Mol Immunol ; 123: 106-115, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32485469

RESUMO

Hepatocytes are the targets in autoimmune hepatitis (AIH) that results in T cell-dependent liver injury. However, hepatocytes may also affect the hepatic T cells in AIH, but the underlying mechanisms are not fully understood. Here we report that hepatocytes could secrete galectin-9 (Gal-9) to suppress the intrahepatic production of Th1 cytokine IFN-γ and restrict AIH development, but hepatocyte damage resulted in opposite effects due to release of TLR2/4 ligands that promoted the intrahepatic production of IL-1ß, IL-6, and IL-12. Through Tim-3, Gal-9 could efficiently suppress the intrahepatic T cell activation despite presence of TLR2/4 ligands, thus attenuating Th1 response in AIH. Intriguingly, intrahepatic IL-6/IL-12 suppressed the effect of TGF-ß on Treg cells. Therefore, in AIH, Gal-9 promoted Foxp3 expression and function of hepatic Treg cells through TL1A signaling, although Treg function was still impaired, compared with that in naive state. Due to its promoting effect on Treg function, together with its effect on T effector cells in a Tim-3-independent way, Gal-9 could attenuate intrahepatic IFN-γ production by hindering the increase of hepatic CD4+CD43+ T cells resulting from extrahepatic T cell activation. TLR2/4 ligands attenuated the effects of Gal-9 on Treg cells and CD4+CD43+ T cells by increasing intrahepatic IL-6 and IL-12. Blocking TLR2/4 ligands could efficiently suppress intrahepatic IFN-γ production, liver injury, and hepatic fibrosis. These findings suggest that hepatocytes paradoxically affect Th1 response in AIH due to Gal-9 expression and TLR2/4 ligands release, and that targeting TLR2/4 signaling may provide an important approach in the therapeutic strategy for AIH.


Assuntos
Galectinas/metabolismo , Hepatite Autoimune/metabolismo , Hepatócitos/fisiologia , Interferon gama/metabolismo , Fígado/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Células Cultivadas , Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Ligantes , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Células Th1/imunologia , Células Th1/metabolismo
17.
J Transl Med ; 18(1): 196, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: covidwho-245284

RESUMO

BACKGROUND: We present the rationale for a novel allo-priming approach to serve the elderly as a universal anti-virus vaccine, as well serving to remodel the aging immune system in order to reverse immunosenescence and inflammaging. This approach has the potential to protect the most vulnerable from disease and provide society an incalculable economic benefit. Allo-priming healthy elderly adults is proposed to provide universal protection from progression of any type of viral infection, including protection against progression of the current outbreak of COVID-19 infection, and any future variants of the causative SARS-CoV-2 virus or the next 'Disease X'. Allo-priming is an alternative approach for the COVID-19 pandemic that provides a back-up in case vaccination strategies to elicit neutralizing antibody protection fails or fails to protect the vulnerable elderly population. The allo-priming is performed using activated, intentionally mismatched, ex vivo differentiated and expanded living Th1-like cells (AlloStim®) derived from healthy donors currently in clinical use as an experimental cancer vaccine. Multiple intradermal injections of AlloStim® creates a dominate titer of allo-specific Th1/CTL memory cells in circulation, replacing the dominance of exhausted memory cells of the aged immune system. Upon viral encounter, by-stander activation of the allo-specific memory cells causes an immediate release of IFN-ϒ, leading to development of an "anti-viral state", by-stander activation of innate cellular effector cells and activation of cross-reactive allo-specific CTL. In this manner, the non-specific activation of allo-specific Th1/CTL initiates a cascade of spatial and temporal immune events which act to limit the early viral titer. The release of endogenous heat shock proteins (HSP) and DAMP from lysed viral-infected cells, in the context of IFN-ϒ, creates of conditions for in situ vaccination leading to viral-specific Th1/CTL immunity. These viral-specific Th1/CTL provide sterilizing immunity and memory for protection from disease recurrence, while increasing the pool of Th1/CTL in circulation capable of responding to the next viral encounter. CONCLUSION: Allo-priming has potential to provide universal protection from viral disease and is a strategy to reverse immunosenescence and counter-regulate chronic inflammation (inflammaging). Allo-priming can be used as an adjuvant for anti-viral vaccines and as a counter-measure for unknown biological threats and bio-economic terrorism.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Memória Imunológica , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Células Th1/imunologia , Vacinas Virais , Adulto , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Apresentação do Antígeno , Infecções por Coronavirus/imunologia , Humanos , Pneumonia Viral/imunologia , Vacinas Virais/imunologia
18.
PLoS One ; 15(5): e0233047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392269

RESUMO

Fruits have been widely considered as the default "health foods" because they contain numerous vitamins and minerals needed to sustain human health. Fermentation strategies have been utilized to enhance the nutritive and flavor features of healthy and readily consumable fruit products while extending their shelf lives. A traditional fermented multi-fruit beverage was made from five fruits including kiwi, guava, papaya, pineapple, and grape fermented by Saccharomyces cerevisiae along with lactic acid bacteria and acetic acid bacteria. The immunomodulatory properties of the fermented multi-fruit beverage, in vivo nonspecific and ovalbumin (OVA)-specific immune response experiments using female BALB/c mice were performed. Administration of the fermented multi-fruit beverage reduced the calorie intake, thus resulting in a less weight gain in mice compared to the water (placebo)-fed mice. In the nonspecific immune study model, the fermented multi-fruit beverage enhanced phagocytosis and T cell proliferation but did not affect B cell proliferation and immunoglobulin G (IgG) production. Analysis of cytokine secretion profile also revealed that the fermented multi-fruit beverage enhanced proinflammatory cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, and T helper (Th)1-related cytokine interferon (IFN)-γ production, thus creating an immunostimulatory effect. Nonetheless, in the specific immune study model, the results showed that the fermented multi-fruit beverage decreased the production of proinflammatory cytokines IL-6 and TNF-α production in OVA-immunized mice. Moreover, it also caused a decrease in the production of anti-OVA IgG1, which was accompanied by a decrease in Th2-related cytokines IL-4 and IL-5 production and an increase in Th1-related cytokine IFN-γ production, indicating that it may have the potential to shift the immune system from the allergen-specific Th2 responses toward Th1-type responses. The results indicate that fermented multi-fruit beverage has the potential to modulate immune responses both in a nonspecific and specific manners.


Assuntos
Citocinas/metabolismo , Alimentos e Bebidas Fermentados/microbiologia , Frutas/imunologia , Ovalbumina/administração & dosagem , Linfócitos T/metabolismo , Acetobacteraceae/fisiologia , Administração Oral , Animais , Peso Corporal , Feminino , Imunoglobulina G/metabolismo , Lactobacillales/fisiologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Fagocitose , Saccharomyces cerevisiae/fisiologia , Células Th1/imunologia , Células Th2/imunologia , Vacinação
19.
Nat Immunol ; 21(6): 671-683, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32424366

RESUMO

Urinary tract infections (UTIs) typically evoke prompt and vigorous innate bladder immune responses, including extensive exfoliation of the epithelium. To explain the basis for the extraordinarily high recurrence rates of UTIs, we examined adaptive immune responses in mouse bladders. We found that, following each bladder infection, a highly T helper type 2 (TH2)-skewed immune response directed at bladder re-epithelialization is observed, with limited capacity to clear infection. This response is initiated by a distinct subset of CD301b+OX40L+ dendritic cells, which migrate into the bladder epithelium after infection before trafficking to lymph nodes to preferentially activate TH2 cells. The bladder epithelial repair response is cumulative and aberrant as, after multiple infections, the epithelium was markedly thickened and bladder capacity was reduced relative to controls. Thus, recurrence of UTIs and associated bladder dysfunction are the outcome of the preferential focus of the adaptive immune response on epithelial repair at the expense of bacterial clearance.


Assuntos
Cistite/etiologia , Cistite/metabolismo , Ativação Linfocitária/imunologia , Membrana Mucosa/imunologia , Membrana Mucosa/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Animais , Carga Bacteriana , Biomarcadores , Linhagem Celular , Cistite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Knockout , Membrana Mucosa/patologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Infecções Urinárias/etiologia , Infecções Urinárias/metabolismo , Infecções Urinárias/microbiologia , Cicatrização/genética , Cicatrização/imunologia
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