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1.
Sci Rep ; 11(1): 16535, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400739

RESUMO

Adaptive immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dynamics remain largely unknown. The neutralizing antibody (NAb) levels in patients with coronavirus disease 2019 (COVID-19) are helpful for understanding the pathology. Using SARS-CoV-2 pseudotyped virus, serum sample neutralization values in symptomatic COVID-19 patients were measured using the chemiluminescence reduction neutralization test (CRNT). At least two sequential serum samples collected during hospitalization were analyzed to assess NAbs neutralizing activity dynamics at different time points. Of the 11 patients, four (36.4%), six (54.5%), and one (9.1%) had moderate, severe, and critical disease, respectively. Fifty percent neutralization (N50%-CRNT) was observed upon admission in 90.9% (10/11); all patients acquired neutralizing activity 2-12 days after onset. In patients with moderate disease, neutralization was observed at earliest within two days after symptom onset. In patients with severe-to-critical disease, neutralization activity increased, plateauing 9-16 days after onset. Neutralization activity on admission was significantly higher in patients with moderate disease than in patients with severe-to-critical disease (relative % of infectivity, 6.4% vs. 41.1%; P = .011). Neutralization activity on admission inversely correlated with disease severity. The rapid NAb response may play a crucial role in preventing the progression of COVID-19.


Assuntos
Imunidade Adaptativa , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , SARS-CoV-2/imunologia , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/estatística & dados numéricos , Estudos Retrospectivos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Fatores de Tempo
3.
Lancet Haematol ; 8(9): e666-e669, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34450104

RESUMO

Vaccines are the most effective measure to prevent deaths and illness from infectious diseases. Nevertheless, the efficacy of several paediatric vaccines is lower in low-income and middle-income countries (LMICs), where mortality from vaccine-preventable infections remains high. Vaccine efficacy can also be decreased in adults in the context of some common comorbidities. Identifying and correcting the specific causes of impaired vaccine efficacy is of substantial value to global health. Iron deficiency is the most common micronutrient deficiency worldwide, affecting more than 2 billion people, and its prevalence in LMICs could increase as food security is threatened by the COVID-19 pandemic. In this Viewpoint, we highlight evidence showing that iron deficiency limits adaptive immunity and responses to vaccines, representing an under-appreciated additional disadvantage to iron deficient populations. We propose a framework for urgent detailed studies of iron-vaccine interactions to investigate and clarify the issue. This framework includes retrospective analysis of newly available datasets derived from trials of COVID-19 and other vaccines, and prospective testing of whether nutritional iron interventions, commonly used worldwide to combat anaemia, improve vaccine performance.


Assuntos
Imunidade Adaptativa , Anemia Ferropriva/complicações , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Países em Desenvolvimento , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação
4.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445503

RESUMO

Obesity is a major risk factor for developing cancer, with obesity-induced immune changes and inflammation in breast (BC) and colorectal cancer (CRC) providing a potential link between the two. This study investigates systemic effects of obesity on adaptive and innate immune cells in healthy and tumour-bearing mice. Immune cells from lean and obese mice were phenotyped prior to implantation of either BC (C57mg and EO771.LMB) or CRC (MC38) cells as tumour models. Tumour growth rate, tumour-infiltrating lymphocytes (TIL) and peripheral blood immune cell populations were compared between obese and lean mice. In vitro studies showed that naïve obese mice had higher levels of myeloid cells in the bone marrow and bone marrow-derived dendritic cells expressed lower levels of activation markers compared to cells from their lean counterparts. In the tumour setting, BC tumours grew faster in obese mice than in lean mice and lower numbers of TILs as well as higher frequency of exhausted T cells were observed. Data from peripheral blood showed lower levels of myeloid cells in tumour-bearing obese mice. This study highlights that systemic changes to the immune system are relevant for tumour burden and provides a potential mechanism behind the effects of obesity on cancer development and progression in patients.


Assuntos
Neoplasias da Mama/patologia , Neoplasias Colorretais/patologia , Linfócitos do Interstício Tumoral/metabolismo , Obesidade/imunologia , Imunidade Adaptativa , Animais , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Neoplasias Colorretais/imunologia , Feminino , Humanos , Masculino , Camundongos , Células Mieloides/metabolismo , Transplante de Neoplasias , Microambiente Tumoral
5.
Sci Adv ; 7(34)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34407944

RESUMO

The COVID-19 pandemic has spread worldwide, yet the role of antiviral T cell immunity during infection and the contribution of immune checkpoints remain unclear. By prospectively following a cohort of 292 patients with melanoma, half of which treated with immune checkpoint inhibitors (ICIs), we identified 15 patients with acute or convalescent COVID-19 and investigated their transcriptomic, proteomic, and cellular profiles. We found that ICI treatment was not associated with severe COVID-19 and did not alter the induction of inflammatory and type I interferon responses. In-depth phenotyping demonstrated expansion of CD8 effector memory T cells, enhanced T cell activation, and impaired plasmablast induction in ICI-treated COVID-19 patients. The evaluation of specific adaptive immunity in convalescent patients showed higher spike (S), nucleoprotein (N), and membrane (M) antigen-specific T cell responses and similar induction of spike-specific antibody responses. Our findings provide evidence that ICI during COVID-19 enhanced T cell immunity without exacerbating inflammation.


Assuntos
COVID-19/imunologia , Inibidores de Checkpoint Imunológico/imunologia , Melanoma/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Imunidade Adaptativa/imunologia , Idoso , Anticorpos Antivirais/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , COVID-19/complicações , COVID-19/virologia , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Melanoma/complicações , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/virologia
6.
Int J Mol Sci ; 22(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34360684

RESUMO

The outbreak of the coronavirus disease 2019 (COVID-19) began at the end of 2019. COVID-19 is caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and patients with COVID-19 may exhibit poor clinical outcomes. Some patients with severe COVID-19 experience cytokine release syndrome (CRS) or a cytokine storm-elevated levels of hyperactivated immune cells-and circulating pro-inflammatory cytokines, including interleukin (IL)-1ß and IL-18. This severe inflammatory response can lead to organ damage/failure and even death. The inflammasome is an intracellular immune complex that is responsible for the secretion of IL-1ß and IL-18 in various human diseases. Recently, there has been a growing number of studies revealing a link between the inflammasome and COVID-19. Therefore, this article summarizes the current literature regarding the inflammasome complex and COVID-19.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Inflamassomos/imunologia , Inflamassomos/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Imunidade Adaptativa/imunologia , Animais , COVID-19/complicações , COVID-19/tratamento farmacológico , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/imunologia , Humanos , Insuficiência de Múltiplos Órgãos/tratamento farmacológico , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/imunologia
7.
Blood Cancer J ; 11(8): 142, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376633

RESUMO

This study evaluated the safety and immunogenicity of BNT162b2 vaccine in patients with hematological malignancies. Antibodies blocking spike binding to immobilized ACE-2 (NAb) correlated with anti-Spike (S) IgG d42 titers (Spearman r = 0.865, p < 0.0001), and an anti-S IgG d42 level ≥3100 UA/mL was predictive of NAb ≥ 30%, the positivity cutoff for NAb (p < 0.0001). Only 47% of the patients achieved an anti-S IgG d42 level ≥3100 UA/mL after the two BNT162b2 inocula, compared to 87% of healthy controls. In multivariable analysis, male patients, use of B-cell targeting treatment within the last 12 months prior to vaccination, and CD19+ B-cell level <120/uL, were associated with a significantly decreased probability of achieving a protective anti-S IgG level after the second BNT162b2 inoculum. Finally, using the IFN-γ ELISPOT assay, we found a significant increase in T-cell response against the S protein, with 53% of patients having an anti-S IgG-positive ELISPOT after the second BNT162b2 inoculum. There was a correlation between the anti-S ELISPOT response and IgG d42 level (Spearman r = 0.3026, p = 0.012). These findings suggest that vaccination with two BNT162b2 inocula translates into a significant increase in humoral and cellular response in patients with hematological malignancies, but only around half of the patients can likely achieve effective immune protection against COVID-19.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/complicações , COVID-19/imunologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/imunologia , Imunogenicidade da Vacina , SARS-CoV-2/imunologia , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/administração & dosagem , Comorbidade , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem
8.
Int J Mol Sci ; 22(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34445670

RESUMO

While first and foremost considered a respiratory infection, COVID-19 can result in complications affecting multiple organs. Immune responses in COVID-19 can both protect against the disease as well as drive it. Insights into these responses, and specifically the targets being recognised by the immune system, are of vital importance in understanding the side effects of COVID-19 and associated pathologies. The body's adaptive immunity recognises and responds against specific targets (antigens) expressed by foreign pathogens, but not usually to target self-antigens. However, if the immune system becomes dysfunctional, adaptive immune cells can react to self-antigens, which can result in autoimmune disease. Viral infections are well reported to be associated with, or exacerbate, autoimmune diseases such as multiple sclerosis (MS) and systemic lupus erythematosus (SLE). In COVID-19 patients, both new onset MS and SLE, as well as the occurrence of other autoimmune-like pathologies, have been reported. Additionally, the presence of autoantibodies, both with and without known associations to autoimmune diseases, have been found. Herein we describe the mechanisms of virally induced autoimmunity and summarise some of the emerging reports on the autoimmune-like diseases and autoreactivity that is reported to be associated with SARS-CoV-2 infection.


Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/virologia , COVID-19/imunologia , Imunidade Adaptativa , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Autoimunidade , COVID-19/virologia , Humanos , Lúpus Eritematoso Sistêmico/imunologia , SARS-CoV-2/imunologia
9.
Biosci Rep ; 41(8)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34350941

RESUMO

An influenza-like virus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for COVID-19 disease and spread worldwide within a short time. COVID-19 has now become a significant concern for public health. Obesity is highly prevalent worldwide and is considered a risk factor for impairing the adaptive immune system. Although diabetes, hypertension, cardiovascular disease (CVD), and renal failure are considered the risk factors for COVID-19, obesity is not yet well-considered. The present study approaches establishing a systemic association between the prevalence of obesity and its impact on immunity concerning the severe outcomes of COVID-19 utilizing existing knowledge. Overall study outcomes documented the worldwide prevalence of obesity, its effects on immunity, and a possible underlying mechanism covering obesity-related risk pathways for the severe outcomes of COVID-19. Overall understanding from the present study is that being an immune system impairing factor, the role of obesity in the severe outcomes of COVID-19 is worthy.


Assuntos
Imunidade Adaptativa/imunologia , COVID-19/patologia , Obesidade/imunologia , Obesidade/patologia , Humanos , Inflamação/patologia , Obesidade/epidemiologia , Fatores de Risco , SARS-CoV-2/imunologia
10.
Gene ; 803: 145899, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34400278

RESUMO

Small-sized and trypanotolerant West African taurine (Bos taurus) cattle are a unique case of human-mediated process of adaptation to a challenging environment. Extensive gene flow with Sahelian zebu (B. indicus), bigger and with some resistance to tick attack, occurred for centuries and allowed the apparition of stable crossbred populations (sanga) having intermediate characteristics. Up to 237 individuals belonging to 10 different taurine, zebu and sanga cattle populations sampled in Benin, Burkina Faso and Niger were typed using the BovineHD BeadChip of Illumina to identify signatures of selection, assessed using three different Extended-Haplotype-Homozygosity-based statistics, overlapping with ancient, originated 1024 or 2048 generations ago, Homozygosity-By-Descent segments in the cattle genome. Candidate genomic regions were defined ensuring their importance within cattle type and using zebu as reference. Functional annotation analysis identified four statistically significant Annotation Clusters in taurine cattle (from ACt1 to ACt4), one (ACs1) in sanga, and another (ACz1) in zebu cattle, fitting well with expectations. ACt1 included genes primarily associated with innate immunity; ACt2 involved bitter taste receptor genes of importance to adaptation to changing environments; ACt3 included 68 genes coding ATP-binding proteins, some of them located on trypanotolerance-related QTL regions, that can partially underlie immune response and the additive mechanism of trypanotolerance; ACt4 was associated with growth and small size (NPPC gene); ACs1 included genes involved in immune response; and ACz1 is related with ectoparasite resistance. Our results provide a new set of genomic areas and candidate genes giving new insights on the genomic impact of adaptation in West African cattle.


Assuntos
Imunidade Adaptativa , Bovinos/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Adaptação Fisiológica , Animais , Benin , Burkina Faso , Resistência à Doença , Fluxo Gênico , Níger , Melhoramento Vegetal , Seleção Genética
11.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204581

RESUMO

Parkinson's disease (PD) is considered the most common disorder of synucleinopathy, which is characterised by intracellular inclusions of aggregated and misfolded α-synuclein (α-syn) protein in various brain regions, and the loss of dopaminergic neurons. During the early prodromal phase of PD, synaptic alterations happen before cell death, which is linked to the synaptic accumulation of toxic α-syn specifically in the presynaptic terminals, affecting neurotransmitter release. The oligomers and protofibrils of α-syn are the most toxic species, and their overexpression impairs the distribution and activation of synaptic proteins, such as the SNARE complex, preventing neurotransmitter exocytosis and neuronal synaptic communication. In the last few years, the role of the immune system in PD has been increasingly considered. Microglial and astrocyte activation, the gene expression of proinflammatory factors, and the infiltration of immune cells from the periphery to the central nervous system (CNS) represent the main features of the inflammatory response. One of the actors of these processes is α-syn accumulation. In light of this, here, we provide a systematic review of PD-related α-syn and inflammation inter-players.


Assuntos
Suscetibilidade a Doenças , Doença de Parkinson/metabolismo , Sinapses/metabolismo , alfa-Sinucleína/metabolismo , Imunidade Adaptativa , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Biomarcadores , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Imunidade Inata , Microglia/imunologia , Microglia/metabolismo , Microglia/patologia , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Sinapses/imunologia , alfa-Sinucleína/genética
12.
Nutrients ; 13(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203776

RESUMO

Living longer is associated with an increased risk of chronic diseases, including impairments of the musculoskeletal and immune system as well as metabolic disorders and certain cancers, each of which can negatively affect the relationship between host and microbiota up to the occurrence of dysbiosis. On the other hand, lifestyle factors, including regular physical exercise and a healthy diet, can affect skeletal muscle and immune aging positively at all ages. Accordingly, health benefits could partly depend on the effect of such interventions that influence the biodiversity and functionality of intestinal microbiota. In the present review, we first discuss the physiological effects of aging on the gut microbiota, immune system, and skeletal muscle. Secondly, we describe human epidemiological evidence about the associations between physical activity and fitness and the gut microbiota composition in older adults. The third part highlights the relevance and restorative mechanisms of immune protection through physical activity and specific exercise interventions during aging. Fourth, we present important research findings on the effects of exercise and protein as well as other nutrients on skeletal muscle performance in older adults. Finally, we provide nutritional recommendations to prevent malnutrition and support healthy active aging with a focus on gut microbiota. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low muscle mass and a higher demand for specific nutrients (e.g., dietary fiber, polyphenols and polyunsaturated fatty acids) that can modify the composition, diversity, and metabolic capacity of the gut microbiota, and may thus provide a practical means of enhancing gut and systemic immune function.


Assuntos
Envelhecimento/fisiologia , Dieta , Microbioma Gastrointestinal/fisiologia , Inflamação , Estilo de Vida , Imunidade Adaptativa , Envelhecimento/imunologia , Desempenho Atlético/fisiologia , Fibras na Dieta , Disbiose , Exercício Físico , Humanos , Sistema Imunitário , Músculo Esquelético/fisiologia , Músculos , Estado Nutricional , Sarcopenia
13.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299236

RESUMO

Inflammatory bowel disease (IBD) is a heterogeneous state of chronic intestinal inflammation of unknown cause encompassing Crohn's disease (CD) and ulcerative colitis (UC). IBD has been linked to genetic and environmental factors, microbiota dysbiosis, exacerbated innate and adaptive immunity and epithelial intestinal barrier dysfunction. IBD is classically associated with gut accumulation of proinflammatory Th1 and Th17 cells accompanied by insufficient Treg numbers and Tr1 immune suppression. Inflammatory T cells guide innate cells to perpetuate a constant hypersensitivity to microbial antigens, tissue injury and chronic intestinal inflammation. Recent studies of intestinal mucosal homeostasis and IBD suggest involvement of innate lymphoid cells (ILCs). These lymphoid-origin cells are innate counterparts of T cells but lack the antigen receptors expressed on B and T cells. ILCs play important roles in the first line of antimicrobial defense and contribute to organ development, tissue protection and regeneration, and mucosal homeostasis by maintaining the balance between antipathogen immunity and commensal tolerance. Intestinal homeostasis requires strict regulation of the quantity and activity of local ILC subpopulations. Recent studies demonstrated that changes to ILCs during IBD contribute to disease development. A better understanding of ILC behavior in gastrointestinal homeostasis and inflammation will provide valuable insights into new approaches to IBD treatment. This review summarizes recent research into ILCs in intestinal homeostasis and the latest advances in the understanding of the role of ILCs in IBD, with particular emphasis on the interaction between microbiota and ILC populations and functions.


Assuntos
Imunidade Inata/imunologia , Mucosa Intestinal/metabolismo , Linfócitos/metabolismo , Imunidade Adaptativa/imunologia , Animais , Colite , Colite Ulcerativa , Doença de Crohn , Trato Gastrointestinal , Homeostase/fisiologia , Humanos , Tolerância Imunológica , Inflamação , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/fisiopatologia , Mucosa Intestinal/imunologia , Intestinos/imunologia , Linfócitos/imunologia , Microbiota , Células Th17
14.
Cytokine ; 146: 155637, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34242899

RESUMO

Interferons have prominent roles in various pathophysiological conditions, mostly related to inflammation. Interferon-gamma (IFNγ) was, initially discovered as a potent antiviral agent, over 50 years ago, and has recently garnered renewed interest as a promising factor involved in both innate and adaptive immunity. When new disease epidemics appear such as SARS-CoV (severe acute respiratory syndrome coronavirus), MERS-CoV (Middle East respiratory syndrome coronavirus), IAV (Influenza A virus), and in particular the current SARS-CoV-2 pandemic, it is especially timely to review the complexity of immune system responses to viral infections. Here we consider the controversial roles of effectors like IFNγ, discussing its actions in immunomodulation and immunotolerance. We explore the possibility that modulation of IFNγ could be used to influence the course of such infections. Importantly, not only could endogenous expression of IFNγ influence the outcome, there are existing IFNγ therapeutics that can readily be applied in the clinic. However, our understanding of the molecular mechanisms controlled by IFNγ suggests that the exact timing for application of IFNγ-based therapeutics could be crucial: it should be earlier to significantly reduce the viral load and thus decrease the overall severity of the disease.


Assuntos
Imunidade Adaptativa/imunologia , COVID-19/imunologia , Tolerância Imunológica/imunologia , Imunidade Inata/imunologia , Interferon gama/imunologia , Antivirais/imunologia , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/virologia , Humanos , Interferon gama/uso terapêutico , Receptores de Interferon/imunologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Transdução de Sinais/imunologia
15.
Nature ; 596(7870): 114-118, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34262174

RESUMO

Pathogenic fungi reside in the intestinal microbiota but rarely cause disease. Little is known about the interactions between fungi and the immune system that promote commensalism. Here we investigate the role of adaptive immunity in promoting mutual interactions between fungi and host. We find that potentially pathogenic Candida species induce and are targeted by intestinal immunoglobulin A (IgA) responses. Focused studies on Candida albicans reveal that the pathogenic hyphal morphotype, which is specialized for adhesion and invasion, is preferentially targeted and suppressed by intestinal IgA responses. IgA from mice and humans directly targets hyphal-enriched cell-surface adhesins. Although typically required for pathogenesis, C. albicans hyphae are less fit for gut colonization1,2 and we show that immune selection against hyphae improves the competitive fitness of C. albicans. C. albicans exacerbates intestinal colitis3 and we demonstrate that hyphae and an IgA-targeted adhesin exacerbate intestinal damage. Finally, using a clinically relevant vaccine to induce an adhesin-specific immune response protects mice from C. albicans-associated damage during colitis. Together, our findings show that adaptive immunity suppresses harmful fungal effectors, with benefits to both C. albicans and its host. Thus, IgA uniquely uncouples colonization from pathogenesis in commensal fungi to promote homeostasis.


Assuntos
Imunidade Adaptativa , Candida albicans/imunologia , Candida albicans/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Simbiose/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Fungos/imunologia , Candida albicans/patogenicidade , Colite/imunologia , Colite/microbiologia , Colite/patologia , Feminino , Vacinas Fúngicas/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Hifas/imunologia , Imunoglobulina A/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
16.
Science ; 373(6554)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326208

RESUMO

Emerging studies indicate that the immune system can regulate systemic metabolism. Here, we show that thymic stromal lymphopoietin (TSLP) stimulates T cells to induce selective white adipose loss, which protects against obesity, improves glucose metabolism, and mitigates nonalcoholic steatohepatitis. Unexpectedly, adipose loss was not caused by alterations in food intake, absorption, or energy expenditure. Rather, it was induced by the excessive loss of lipids through the skin as sebum. TSLP and T cells regulated sebum release and sebum-associated antimicrobial peptide expression in the steady state. In human skin, TSLP expression correlated directly with sebum-associated gene expression. Thus, we establish a paradigm in which adipose loss can be achieved by means of sebum hypersecretion and uncover a role for adaptive immunity in skin barrier function through sebum secretion.


Assuntos
Tecido Adiposo Branco/anatomia & histologia , Citocinas/metabolismo , Sebo/metabolismo , Pele/metabolismo , Imunidade Adaptativa , Animais , Citocinas/genética , Dieta , Glucose/metabolismo , Homeostase , Humanos , Imunoglobulinas/metabolismo , Metabolismo dos Lipídeos , Camundongos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/prevenção & controle , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Receptores de Citocinas/metabolismo , Glândulas Sebáceas/metabolismo , Transdução de Sinais , Pele/imunologia , Linfócitos T/fisiologia , Perda de Peso
17.
Science ; 373(6554): 510-516, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326232

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease in which T cells attack and destroy the insulin-producing ß cells in the pancreatic islets. Genetic and environmental factors increase T1D risk by compromising immune homeostasis. Although the discovery and use of insulin have transformed T1D treatment, insulin therapy does not change the underlying disease or fully prevent complications. Over the past two decades, research has identified multiple immune cell types and soluble factors that destroy insulin-producing ß cells. These insights into disease pathogenesis have enabled the development of therapies to prevent and modify T1D. In this review, we highlight the key events that initiate and sustain pancreatic islet inflammation in T1D, the current state of the immunological therapies, and their advantages for the treatment of T1D.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Fatores Imunológicos/uso terapêutico , Imunoterapia , Imunidade Adaptativa , Animais , Anti-Inflamatórios/uso terapêutico , Autoanticorpos/sangue , Linfócitos B/imunologia , Citocinas/imunologia , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Humanos , Imunidade Inata , Células Secretoras de Insulina/fisiologia , Interleucina-2/uso terapêutico , Linfócitos T/imunologia
18.
Front Immunol ; 12: 696816, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305933

RESUMO

Early studies on vaccination of children with oncological diseases were only dedicated to the assessment of safety and immunogenicity of the drug. Mechanisms of the post-vaccination immune response were not investigated. This study involved 41 patients aged 7-15 years who were treated for solid tumors two or more years ago. Of these, 26 were vaccinated against diphtheria and tetanus with ADS-m toxoid. Fifteen children (i.e., controls) were not vaccinated. The vaccination tolerability and clinical characteristics of the underlying disease remission ware assessed. Lymphocyte subpopulations were investigated over time by flow cytometry at 1, 6, and 12 months. IgG anti-diphtheria and anti-tetanus toxoids levels were assessed by ELISA. Within the first day of the post-vaccination period, two (7.7%) children demonstrated moderate local reactions and increased body temperature (up to 38.0°C). Relapse and metastasis were not mentioned within a year after immunization. An increase in concentration of IgG antibodies, maintained for 12 months, were noted [2.1 (1.3-3.4) IU/ml against diphtheria (p <0.001), 6.4 (2.3-9.7) IU/ml against tetanus (p <0.001)]. In contrast to healthy children, those with a history of cancer demonstrated a decrease in the relative number of mature T lymphocytes, as well as in absolute number of cytotoxic T cells and B lymphocytes. In a month after the revaccination, a significant increase in absolute (p = 0.04) and relative (p = 0.007) numbers of T lymphocytes and T helpers was revealed. In a year, these values decreased to baseline levels. As for helpers, they decreased below baseline and control values (p = 0.004). In a year after the vaccination, there was a significant (p = 0.05) increase in lymphocyte level with a decrease in the number of NK cells and B cells as compared with controls. Revaccination against diphtheria and tetanus promoted proliferation of a total lymphocytic cell pool along with restoration of the T lymphocyte subpopulation in children with a history of solid tumors. The ADS-m toxoid has a certain nonspecific immunomodulatory effect. These findings are important, also in the midst of the coronavirus pandemic.


Assuntos
Imunidade Adaptativa/imunologia , Vacina contra Difteria e Tétano/imunologia , Neoplasias/imunologia , Vacinação , Adolescente , Anticorpos Antibacterianos/imunologia , Criança , Difteria/imunologia , Difteria/prevenção & controle , Vacina contra Difteria e Tétano/administração & dosagem , Humanos , Imunização Secundária , Subpopulações de Linfócitos/imunologia , Linfócitos/imunologia , Neoplasias/patologia , Federação Russa , Tétano/imunologia , Tétano/prevenção & controle
19.
Trends Immunol ; 42(8): 654-657, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34246558

RESUMO

Broadly neutralizing antibodies against rapidly evolving viruses (e.g., HIV-1 and influenza virus), often manifest antigen-binding promiscuity. Based on a recent study, we hypothesize on the significance of antibody polyreactivity in neutralization of rapidly evolving viruses. We propose that polyreactivity contributes to toleration of viral variants and shortens the time for generating neutralizing antibodies.


Assuntos
HIV-1 , Orthomyxoviridae , Imunidade Adaptativa , Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Anti-HIV , Humanos
20.
Signal Transduct Target Ther ; 6(1): 289, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326311

RESUMO

Pregnant women are generally more susceptible to viral infection. Although the impact of SARS-CoV-2 in pregnancy remains to be determined, evidence indicates that the risk factors for severe COVID-19 are similar in pregnancy to the general population. Here we systemically analyzed the clinical characteristics of pregnant and non-pregnant female COVID-19 patients who were hospitalized during the same period and found that pregnant patients developed marked lymphopenia and higher inflammation evident by higher C-reactive protein and IL-6. To elucidate the pathways that might contribute to immunopathology or protective immunity against COVID-19 during pregnancy, we applied single-cell mRNA sequencing to profile peripheral blood mononuclear cells from four pregnant and six non-pregnant female patients after recovery along with four pregnant and three non-pregnant healthy donors. We found normal clonal expansion of T cells in the pregnant patients, heightened activation and chemotaxis in NK, NKT, and MAIT cells, and differential interferon responses in the monocyte compartment. Our data present a unique feature in both innate and adaptive immune responses in pregnant patients recovered from COVID-19.


Assuntos
Imunidade Adaptativa , COVID-19/imunologia , Imunidade Inata , Linfócitos/imunologia , Complicações Infecciosas na Gravidez/imunologia , SARS-CoV-2/imunologia , Adulto , Proteína C-Reativa/imunologia , Feminino , Humanos , Interleucina-6/imunologia , Gravidez , Estudos Retrospectivos , Análise de Sequência de RNA , Análise de Célula Única
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