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1.
Front Immunol ; 14: 1286001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149254

RESUMO

Introduction: The Portuguese donor Registry of CEDACE was the fifth largest per capita bone marrow donor Registry of the WMDA as of 2019 and has yet to be thoroughly analyzed. We aimed to characterize its various aspects, including demographics and HLA allele and haplotype frequencies, to evaluate the genetic matching propensity score and ultimately further develop it. Methods: We described and compared characteristics of the donor population with census data and used an Expectation-Maximization algorithm and analyses of molecular variance to assess haplotype frequencies and establish phylogenetic distances between regions and districts within the country. Results: We identified 396545 donors, corresponding to 3.85% of the Portuguese population; the median donor age was 39 years, with 60.4% of female donors. Most donors were Portuguese nationals, although 40 other nationalities were present, with a significant proportion of donors from Brazil and Portuguese-speaking African Countries; almost all donors self-reported as Western, with the second largest group reporting African ancestry. There was an asymmetric contribution of donors from different districts and regions, with most coming from coastal districts and few from the southern districts and autonomous regions; foreign and self-declared non-Western donors were mainly located in the Metropolitan Area of Lisbon and the South. Although most donors were typed in three loci (HLA-A, HLA-B and HLA-DRB1), only 44% were also typed in HLA-C, 1.28% in HLA-DQB1 and only 0.77% in all five loci and in high-resolution. There were varying allele and haplotype frequencies across districts and regions, with the most common three loci, low-resolution haplotypes, being HLA-A*01~B*08~DRB1*03, A*29~B*44~DRB1*07 and HLA-A*02~B*44~DRB1*04; some haplotypes were more prevalent in the South, others in the North and a few in the autonomous regions; African and foreign donors presented relevant differences in haplotype frequency distributions, including rare haplotypes of potential interest. We also report on four loci, low-resolution frequency distributions. Using AMOVA, we compared genetic distances between districts and regions, which recapitulated the country's geography. Discussion: Our analysis showed potential paths to optimization of the Registry, including increasing the male donor pool and focusing on underrepresented districts and particular populations of interest, such as donors from Portuguese-speaking African countries.


Assuntos
Medula Óssea , Doadores de Tecidos , Humanos , Masculino , Feminino , Adulto , Frequência do Gene , Filogenia , Portugal , Sistema de Registros , Antígenos HLA-A/genética
2.
Front Immunol ; 12: 592031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335558

RESUMO

Successful outcome of immune checkpoint blockade in patients with solid cancers is in part associated with a high tumor mutational burden (TMB) and the recognition of private neoantigens by T-cells. The quality and quantity of target recognition is determined by the repertoire of 'neoepitope'-specific T-cell receptors (TCRs) in tumor-infiltrating lymphocytes (TIL), or peripheral T-cells. Interferon gamma (IFN-γ), produced by T-cells and other immune cells, is essential for controlling proliferation of transformed cells, induction of apoptosis and enhancing human leukocyte antigen (HLA) expression, thereby increasing immunogenicity of cancer cells. TCR αß-dependent therapies should account for tumor heterogeneity and availability of the TCR repertoire capable of reacting to neoepitopes and functional HLA pathways. Immunogenic epitopes in the tumor-stroma may also be targeted to achieve tumor-containment by changing the immune-contexture in the tumor microenvironment (TME). Non protein-coding regions of the tumor-cell genome may also contain many aberrantly expressed, non-mutated tumor-associated antigens (TAAs) capable of eliciting productive anti-tumor immune responses. Whole-exome sequencing (WES) and/or RNA sequencing (RNA-Seq) of cancer tissue, combined with several layers of bioinformatic analysis is commonly used to predict possible neoepitopes present in clinical samples. At the ImmunoSurgery Unit of the Champalimaud Centre for the Unknown (CCU), a pipeline combining several tools is used for predicting private mutations from WES and RNA-Seq data followed by the construction of synthetic peptides tailored for immunological response assessment reflecting the patient's tumor mutations, guided by MHC typing. Subsequent immunoassays allow the detection of differential IFN-γ production patterns associated with (intra-tumoral) spatiotemporal differences in TIL or peripheral T-cells versus TIL. These bioinformatics tools, in addition to histopathological assessment, immunological readouts from functional bioassays and deep T-cell 'adaptome' analyses, are expected to advance discovery and development of next-generation personalized precision medicine strategies to improve clinical outcomes in cancer in the context of i) anti-tumor vaccination strategies, ii) gauging mutation-reactive T-cell responses in biological therapies and iii) expansion of tumor-reactive T-cells for the cellular treatment of patients with cancer.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Epitopos de Linfócito T/imunologia , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/imunologia , Linfócitos T/imunologia , Animais , Biologia Computacional , Humanos , Neoplasias/terapia , Medicina de Precisão , Linfócitos T/transplante , Sequenciamento Completo do Genoma
3.
Immunohorizons ; 5(5): 307-321, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980663

RESUMO

Regulatory T cell (Treg) infusion for graft-versus-host disease treatment has been increasingly investigated. However, polyclonal Treg may suppress the desired graft-versus-leukemia effect. Although allogeneic-specific (allo-specific) Treg may provide a more-targeted graft-versus-host disease treatment, there is the need to develop easily translatable expansion protocols and to better characterize their specificity and mechanisms of suppression. In this article, we provide a robust protocol for human allo-specific Treg expansion and characterize their phenotype, potency, and specificity of suppression by testing different expansion conditions and suppression assay milieus. We found that higher concentrations of IL-2 during expansion with allogeneic APC yielded allo-specific Treg that were more-potent suppressors and displayed a more activated phenotype. Although responses to the same APC present during expansion were the most suppressed, responses to third-party APC partially matched to the expansion APC were still significantly more suppressed than responses to fully mismatched APC. Furthermore, suppression of responses to the expansion APC was strictly contact dependent, whereas suppression of responses to mismatched APC was partially independent of contact. Finally, distinct subsets in fresh and expanded Treg could be described using multidimensional visualization techniques. We propose that allo-specific Treg are HLA specific and that the mechanisms of suppression elicited depend on their compatibility with the stimulators.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Antígenos HLA/imunologia , Linfócitos T Reguladores/imunologia , Técnicas de Cocultura , Doença Enxerto-Hospedeiro/etiologia , Teste de Histocompatibilidade , Humanos , Transplante Homólogo
4.
mBio ; 12(3): e0036921, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34044589

RESUMO

Activation of immune cells in response to fungal infection involves the reprogramming of their cellular metabolism to support antimicrobial effector functions. Although metabolic pathways such as glycolysis are known to represent critical regulatory nodes in antifungal immunity, it remains undetermined whether these are differentially regulated at the interindividual level. In this study, we identify a key role for 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in the immunometabolic responses to Aspergillus fumigatus. A genetic association study performed in 439 recipients of allogeneic hematopoietic stem cell transplantation (HSCT) and corresponding donors revealed that the donor, but not recipient, rs646564 variant in the PFKFB3 gene increased the risk of invasive pulmonary aspergillosis (IPA) after transplantation. The risk genotype impaired the expression of PFKFB3 by human macrophages in response to fungal infection, which was correlated with a defective activation of glycolysis and the ensuing antifungal effector functions. In patients with IPA, the risk genotype was associated with lower concentrations of cytokines in the bronchoalveolar lavage fluid samples. Collectively, these findings demonstrate the important contribution of genetic variation in PFKFB3 to the risk of IPA in patients undergoing HSCT and support its inclusion in prognostic tools to predict the risk of fungal infection in this clinical setting. IMPORTANCE The fungal pathogen Aspergillus fumigatus can cause severe and life-threatening forms of infection in immunocompromised patients. Activation of glycolysis is essential for innate immune cells to mount effective antifungal responses. In this study, we report the contribution of genetic variation in the key glycolytic activator 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) to the risk of invasive pulmonary aspergillosis (IPA) after allogeneic hematopoietic stem cell transplantation. The PFKFB3 genotype associated with increased risk of infection was correlated with an impairment of the antifungal effector functions of macrophages in vitro and in patients with IPA. This work highlights the clinical relevance of genetic variation in PFKFB3 to the risk of IPA and supports its integration in risk stratification and preemptive measures for patients at high risk of IPA.


Assuntos
Variação Genética , Aspergilose Pulmonar Invasiva/genética , Aspergilose Pulmonar Invasiva/imunologia , Macrófagos/imunologia , Fosfofrutoquinase-2/genética , Adolescente , Adulto , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/análise , Citocinas/imunologia , Suscetibilidade a Doenças , Feminino , Genótipo , Glicólise/imunologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Hospedeiro Imunocomprometido , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Fosfofrutoquinase-2/imunologia , Adulto Jovem
5.
Biomedicines ; 8(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352885

RESUMO

The application of innovative three-dimensional (3D) spheroids cell culture strategy to Parasitology offers the opportunity to closely explore host-parasite interactions. Here we present a first report on the application of 3D hepatic spheroids to unravel the immune response of canine hepatocytes exposed to Leishmania infantum. The liver, usually considered a major metabolic organ, also performs several important immunological functions and constitutes a target organ for L. infantum infection, the etiological agent of canine leishmaniasis (CanL), and a parasitic disease of major veterinary and public health concern. 3D hepatic spheroids were able to sense and immunologically react to L. infantum parasites, generating an innate immune response by increasing nitric oxide (NO) production and enhancing toll-like receptor (TLR) 2 and interleukin-10 gene expression. The immune response orchestrated by canine hepatocytes also lead to the impairment of several cytochrome P450 (CYP450) with possible implications for liver natural xenobiotic metabolization capacity. The application of meglumine antimoniate (MgA) increased the inflammatory response of 3D hepatic spheroids by inducing the expression of Nucleotide oligomerization domain (NOD) -like receptors 1 and NOD2 and TLR2, TLR4, and TLR9 and enhancing gene expression of tumour necrosis factor α. It is therefore suggested that hepatocytes are key effector cells and can activate and orchestrate the immune response to L. infantum parasites.

6.
Adv Exp Med Biol ; 1273: 175-195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33119882

RESUMO

We review state-of-the-art in translational and clinical studies focusing on the tumor microenvironment (TME) with a focus on tumor-infiltrating B cells (TIBs). The TME is a dynamic matrix of mutations, immune-regulatory networks, and distinct cell-to-cell interactions which collectively impact on disease progress. We discuss relevant findings concerning B cells in pancreatic cancer, the concepts of "bystander" B cells, the role of antigen-specific B cells contributing to augmenting anticancer-directed immune responses, the role of B cells as prognostic markers for response to checkpoint inhibitors (ICBs), and the potential use in adoptive cell tumor-infiltrating lymphocyte (TIL) products.


Assuntos
Linfócitos B/citologia , Neoplasias Pancreáticas/imunologia , Microambiente Tumoral/imunologia , Linfócitos B/imunologia , Humanos , Linfócitos do Interstício Tumoral , Neoplasias Pancreáticas/terapia , Medicina de Precisão
7.
Curr Opin Pulm Med ; 25(3): 233-241, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30883448

RESUMO

PURPOSE OF REVIEW: In the light of poor management outcomes of antibiotic-resistant respiratory tract infection (RTI)-associated sepsis syndrome and multidrug-resistant tuberculosis (MDR-TB), new management interventions based on host-directed therapies (HDTs) are warranted to improve morbidity, mortality and long-term functional outcomes. We review developments in potential HDTs based on precision cancer therapy concepts applicable to RTIs including MDR-TB. RECENT FINDINGS: Immune reactivity, tissue destruction and repair processes identified during studies of cancer immunotherapy share common pathogenetic mechanisms with RTI-associated sepsis syndrome and MDR-TB. T-cell receptors (TCRs) and chimeric antigen receptors targeting pathogen-specific or host-derived mutated molecules (major histocompatibility class-dependent/ major histocompatibility class-independent) can be engineered for recognition by TCR γδ and natural killer (NK) cells. T-cell subsets and, more recently, NK cells are shown to be host-protective. These cells can also be activated by immune checkpoint inhibitor (ICI) or derived from allogeneic sources and serve as potential for improving clinical outcomes in RTIs and MDR-TB. SUMMARY: Recent developments of immunotherapy in cancer reveal common pathways in immune reactivity, tissue destruction and repair. RTIs-related sepsis syndrome exhibits mixed immune reactions, making cytokine or ICI therapy guided by robust biomarker analyses, viable treatment options.


Assuntos
Imunoterapia , Medicina de Precisão , Infecções Respiratórias/terapia , Tuberculose Resistente a Múltiplos Medicamentos/terapia , Antituberculosos/uso terapêutico , Citocinas , Humanos , Células Matadoras Naturais/imunologia , Neoplasias/terapia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/imunologia , Subpopulações de Linfócitos T/imunologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/imunologia
8.
Front Immunol ; 10: 334, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30894856

RESUMO

The success of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of hematological malignancies remains hampered by life-threatening chronic graft vs. host disease (cGVHD). Although multifactorial in nature, cGVHD has been associated with imbalances between effector and regulatory T cells (Treg). To further elucidate this issue, we performed a prospective analysis of patients undergoing unrelated donor allo-HSCT after a reduced intensity conditioning (RIC) regimen containing anti-thymocyte globulin (ATG) and the same GVHD prophylaxis, at a single institution. We studied T cell subset homeostasis over a 24-month follow-up after HSCT in a comparative analysis of patients with and without cGVHD. We also quantified naive and memory T cell subsets, proliferation and expression of the apoptosis-related proteins Bcl-2 and CD95. Finally, we assessed thymic function by T cell receptor excision circle (TREC) quantification and T cell receptor (TCR) diversity by TCRVß spectratyping. While the total number of conventional CD4 (Tcon) and CD8 T cells was similar between patient groups, Treg were decreased in cGVHD patients. Interestingly, we also observed divergent patterns of Naive and Stem Cell Memory (SCM) subset recovery in Treg and Tcon compared to CD8. Patients with cGVHD showed impaired recovery of Naive and SCM Tcon and Treg, but significantly increased frequencies and absolute numbers of Naive and SCM were observed in the CD8 pool. Markedly increased EMRA CD8 T cells were also noted in cGVHD. Taken together, these results suggest that Naive, SCM and EMRA CD8 play a role in the emergence of cGHVD. Reduced Naive and recent thymic emigrant Tcon and Treg in cGVHD was likely due to impaired thymic output, as it was accompanied by decreased CD4 TREC and TCR diversity. On the other hand, CD8 TCR diversity was similar between patient groups. Furthermore, no correlation was observed between CD8 TREC content and Naive CD8 numbers, suggesting limited thymic production of Naive CD8 T cells in patients after transplant, especially in those developing cGVHD. The mechanisms behind the opposing patterns of CD4 and CD8 subset cell recovery in cGVHD remain elusive, but may be linked to thymic damage associated with the conditioning regimen and/or acute GVHD.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Células-Tronco/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Soro Antilinfocitário/imunologia , Feminino , Neoplasias Hematológicas/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Memória Imunológica/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T Reguladores/imunologia , Condicionamento Pré-Transplante/métodos , Doadores não Relacionados , Adulto Jovem
9.
Front Immunol ; 10: 88, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30766534

RESUMO

Background: Reactivation of latent human cytomegalovirus (CMV) in patients undergoing allogeneic stem-cell transplantation (HSCT) predisposes to several clinical complications and is therefore a major cause of morbidity and mortality. Although pentraxin-3 (PTX3) has been previously described to bind both human and murine CMV and mediate several host antiviral mechanisms, whether genetic variation in the PTX3 locus influences the risk of CMV infection is currently unknown. Methods: To dissect the contribution of genetic variation within PTX3 to the development of CMV infection, we analyzed described loss-of-function variants at the PTX3 locus in 394 recipients of HSCT and their corresponding donors and assessed the associated risk of CMV reactivation. Results: We report that the donor, but not recipient, h2/h2 haplotype in PTX3 increased the risk of CMV reactivation after 24 months following transplantation, with a significant effect on survival. Among recipients with h2/h2 donors, CMV seropositive patients as well as those receiving grafts from unrelated donors, regardless of the CMV serostatus, were more prone to develop viral reactivation after transplantation. Most importantly, the h2/h2 haplotype was demonstrated to display an influence toward risk of CMV reactivation comparable to that conferred by the unrelated status of the donor alone. Conclusions: Our findings demonstrate the important contribution of genetic variation in donor PTX3 to the risk of CMV reactivation in patients undergoing HSCT, highlighting a promising prognostic value of donor PTX3 to predict risk of CMV reactivation in this clinical setting.


Assuntos
Proteína C-Reativa/genética , Infecções por Citomegalovirus/genética , Citomegalovirus/fisiologia , Genótipo , Transplante de Células-Tronco Hematopoéticas , Componente Amiloide P Sérico/genética , Adolescente , Adulto , Animais , Infecções por Citomegalovirus/epidemiologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Portugal/epidemiologia , Risco , Transplante Homólogo , Ativação Viral , Adulto Jovem
10.
Front Microbiol ; 10: 2924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998254

RESUMO

Memory formation, guided by microbial ligands, has been reported for innate immune cells. Epigenetic imprinting plays an important role herein, involving histone modification after pathogen-/danger-associated molecular patterns (PAMPs/DAMPs) recognition by pattern recognition receptors (PRRs). Such "trained immunity" affects not only the nominal target pathogen, yet also non-related targets that may be encountered later in life. The concept of trained innate immunity warrants further exploration in cancer and how these insights can be implemented in immunotherapeutic approaches. In this review, we discuss our current understanding of innate immune memory and we reference new findings in this field, highlighting the observations of trained immunity in monocytic and natural killer cells. We also provide a brief overview of trained immunity in non-immune cells, such as stromal cells and fibroblasts. Finally, we present possible strategies based on trained innate immunity that may help to devise host-directed immunotherapies focusing on cancer, with possible extension to infectious diseases.

11.
Front Cell Dev Biol ; 7: 362, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32039196

RESUMO

The intricate interplay between the immune system and microbes is an essential part of the physiological homeostasis in health and disease. Immunological recognition of commensal microbes, such as bacterial species resident in the gut or lung as well as dormant viral species, i.e., cytomegalovirus (CMV) or Epstein-Barr virus (EBV), in combination with a balanced immune regulation, is central to achieve immune-protection. Emerging evidence suggests that immune responses primed to guard against commensal microbes may cause unexpected pathological outcomes, e.g., chronic inflammation and/or malignant transformation. Furthermore, translocation of immune cells from one anatomical compartment to another, i.e., the gut-lung axis via the lymphatics or blood has been identified as an important factor in perpetrating systemic inflammation, tissue destruction, as well as modulating host-protective immune responses. We present in this review immune response patterns to pathogenic as well as non-pathogenic microbes and how these immune-recognition profiles affect local immune responses or malignant transformation. We discuss personalized immunological therapies which, directly or indirectly, target host biological pathways modulated by antimicrobial immune responses.

12.
Int J Mol Sci ; 18(7)2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28703772

RESUMO

Post-parturient behavior of mammalian females is essential for early parent-offspring contact. After delivery, lambs need to ingest colostrum for obtaining the related immunological protection, and early interactions between the mother and the lamb are crucial. Despite visual and auditory cues, olfactory cues are decisive in lamb orientation to the mammary gland. In sheep, the inguinal sinus is located bilaterally near the mammary gland as a skin pouch (IGS) that presents a gland that secretes a strong-smelling wax. Sheep IGS gland functions have many aspects under evaluation. The objective of the present study was to evaluate sheep IGS gland functional aspects and mRNA transcription and the protein expression of several hormone receptors, such as progesterone receptor (PGR), estrogen receptor 1 (ESR1), and 2 (ESR2) and prolactin receptor (PRLR) present. In addition, another aim was to achieve information about IGS ultrastructure and chemical compounds produced in this gland. All hormone receptors evaluated show expression in IGS during the estrous cycle (follicular/luteal phases), pregnancy, and the post-partum period. IGS secretion is rich in triterpenoids that totally differ from the surrounding skin. They might be essential substances for the development of an olfactory preference of newborns to their mothers.


Assuntos
Estrogênios/metabolismo , Glândulas Mamárias Animais/anatomia & histologia , Glândulas Mamárias Animais/metabolismo , Progesterona/metabolismo , Receptores da Prolactina/metabolismo , Animais , Feminino , Citometria de Fluxo , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/ultraestrutura , Gravidez , Ovinos
13.
Immunotherapy ; 9(7): 531-535, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28595520

RESUMO

Programmed cell death-1 protein (PD-1) is an immune checkpoint that has gained popularity in the treatment of several advanced cancers. Inhibiting this checkpoint is known to enhance immune response, but is also known to diminish immune tolerance and to increase autoimmune toxicity. We discuss a case of rapid onset fulminant Type 1 diabetes induced by treatment with anti-programmed cell death-1 monoclonal antibody, nivolumab, in a patient with late-stage non-small-cell lung adenocarcinoma. The patient had no history of previous diabetes but did reveal a high-risk genotype for Type 1 diabetes development (DR3-DQ2; DR4-DQ8). This finding supports that acute Type 1 diabetes can be an important adverse effect of immunotherapies targeting T-cell activation regulation. Because of the severity of this adverse effect, physicians should be aware of it, and studies directed to the detection of new biomarkers for early risk stratification (e.g., HLA) should be sought.


Assuntos
Adenocarcinoma/diagnóstico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Diabetes Mellitus Tipo 1/diagnóstico , Imunoterapia/métodos , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma/complicações , Adenocarcinoma/tratamento farmacológico , Idoso , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/genética , Feminino , Predisposição Genética para Doença , Genótipo , Antígenos HLA-DQ/genética , Antígeno HLA-DR3/genética , Antígeno HLA-DR4/genética , Humanos , Imunoterapia/efeitos adversos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe , Receptor de Morte Celular Programada 1/imunologia , Risco
15.
Front Immunol ; 8: 20, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28154568

RESUMO

Naive CD4 T-cell maintenance is critical for immune competence. We investigated here the fine-tuning of homeostatic mechanisms of the naive compartment to counteract the loss of de novo CD4 T-cell generation. Adults thymectomized in early childhood during corrective cardiac surgery were grouped based on presence or absence of thymopoiesis and compared with age-matched controls. We found that the preservation of the CD31- subset was independent of the thymus and that its size is tightly controlled by peripheral mechanisms, including prolonged cell survival as attested by Bcl-2 levels. Conversely, a significant contraction of the CD31+ naive subset was observed in the absence of thymic activity. This was associated with impaired responses of purified naive CD4 T-cells to IL-7, namely, in vitro proliferation and upregulation of CD31 expression, which likely potentiated the decline in recent thymic emigrants. Additionally, we found no apparent constraint in the differentiation of naive cells into the memory compartment in individuals completely lacking thymic activity despite upregulation of DUSP6, a phosphatase associated with increased TCR threshold. Of note, thymectomized individuals featuring some degree of thymopoiesis were able to preserve the size and diversity of the naive CD4 compartment, further arguing against complete thymectomy in infancy. Overall, our data suggest that robust peripheral mechanisms ensure the homeostasis of CD31- naive CD4 pool and point to the requirement of continuous thymic activity to the maintenance of IL-7-driven homeostatic proliferation of CD31+ naive CD4 T-cells, which is essential to secure T-cell diversity throughout life.

16.
Hum Immunol ; 77(10): 832-840, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27377016

RESUMO

The polymorphism of HLA genes can be used to reconstruct human peopling history. However, this huge diversity impairs successful matching in stem cell transplantation, a situation which has led to the recruitment of millions of donors worldwide. In parallel to the increase of recruitment, registries are progressively relying on information from population genetics to optimize their donor pools in terms of HLA variability. In this study, the HLA data of 65,000 Spanish bone marrow donors were analyzed together with 60,000 Portuguese individuals to provide a comprehensive HLA genetic map of the Iberian Peninsula. The frequencies of many alleles were shown to vary continuously across the Peninsula, either increasing or decreasing from the Mediterranean coast to the Atlantic domain or from the Strait of Gibraltar to the Pyrenees and Bay of Biscay. Similar patterns were observed for several haplotypes. In addition, within some regions neighboring provinces share a close genetic similarity. These results outline the genetic landscape of the Iberian Peninsula, and confirm that the analysis of the HLA polymorphism may reveal relevant signatures of past demographic events even when data from donor registries are used. This conclusion stimulates future developments of the Spanish registry, presented here for the first time.


Assuntos
Antígenos HLA/genética , Transplante de Células-Tronco Hematopoéticas , Polimorfismo Genético , Sistema de Registros , Doadores de Tecidos , Frequência do Gene , Genótipo , Teste de Histocompatibilidade , Humanos , Espanha
17.
Arthritis Res Ther ; 17: 81, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25889189

RESUMO

INTRODUCTION: The aim of this study was to characterize the association of human leukocyte antigen (HLA) B alleles and major histocompatibility complex (MHC) single nucleotide polymorphisms (SNPs) with Behçet's disease (BD) in an Iranian dataset. METHODS: The association of three SNPs in the MHC region previously identified as the most associated in high-density genotyping studies was tested in a case-control study on 973 BD patients and 825 controls from Iran, and the association of HLA-B alleles was tested in a subset of 681 patients and 414 controls. RESULTS: We found that HLA-B*51 (P = 4.11 × 10(-41), OR [95% CI] = 4.63[3.66-5.85]) and B*15 confer risk for BD (P = 2.83 × 10(-2), OR [95% CI] = 1.75[1.08-2.84]) in Iranian, and in B*51 negative individuals, only the B*15 allele is significantly associated with BD (P = 2.51 × 10(-3), OR [95% CI] = 2.40[1.37-4.20]). rs76546355, formerly known as rs116799036, located between HLA-B and MICA (MHC class I polypeptide-related sequence A), demonstrated the same level of association with BD as HLA-B*51 (P adj = 1.78 × 10(-46), OR [95% CI] = 5.46[4.21-7.09], and P adj = 8.34 × 10(-48), OR [95% CI] = 5.44[4.20-7.05], respectively) in the HLA-B allelotyped subset, while rs2848713 was less associated (P adj = 7.14 × 10(-35), OR [95% CI] = 3.73[2.97-4.69]) and rs9260997 was not associated (P adj = 1.00 × 10(-1)). Additionally, we found that B*51 genotype-phenotype correlations do not survive Bonferroni correction, while carriers of the rs76546355 risk allele predominate in BD cases with genital ulcers, positive pathergy test and positive BD family history (2.31 × 10(-4) ≤ P ≤ 1.59 × 10(-3)). CONCLUSIONS: We found that the HLA-B*51 allele and the rs76546355/rs116799036 MHC SNP are independent genetic risk factors for BD in Iranian, and that positivity for the rs76546355/rs116799036 risk allele, but not for B*51, does correlate with specific demographic characteristics or clinical manifestations in BD patients.


Assuntos
Síndrome de Behçet/epidemiologia , Síndrome de Behçet/genética , Estudos de Associação Genética , Loci Gênicos/genética , Antígeno HLA-B51/genética , Complexo Principal de Histocompatibilidade/genética , Adulto , Síndrome de Behçet/diagnóstico , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética/métodos , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
18.
Microsc Res Tech ; 77(4): 313-25, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24779038

RESUMO

Many species that belong to Artiodactyls order show an interdigital sinus (IS), as it occurs in sheep, in all four extremities. These are considered to be scent glands responsible for sexual communication having strong attractiveness to mature males at the peak of the breeding season. The aim of this study was to evaluate, in IS in cyclic ewes, the microscopic and ultrastructure (scanning and transmission electron microscopy) anatomy, secretion composition, and mRNA and protein expression of estrogen receptors a and b and progesterone receptors. Glandular sebaceous structures occupy a superficial area of the pouch. The other glands present in the IS show a coiled tubular structure and tall and polyhedral secretory cells with irregular luminal surface resulting from the secretory process. Protein and mRNA gene transcription studies were performed to determine the presence of ER (a and b) and P4r in IS. At the follicular phase, IS cell populations analyzed using flow cytometry expressed higher levels of ERb compared with ERa (P<0.05), whereas no difference was observed between them in the luteal phase. The IS amount of secretion was the highest in the follicular phase compared with luteal phase (P<0.05) or pregnancy (P<0.001).To the best of our knowledge, for the first time, the presence of ER (a and b) within the IS was demonstrated. As estrogen action is mediated by specific receptors in target cells, the presence of these receptors in IS might be needed to trigger signaling pathways involved in conspecific chemical (sexual) communication attributed to this area.


Assuntos
Glândulas Exócrinas/anatomia & histologia , Glândulas Exócrinas/metabolismo , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Ovinos/genética , Animais , Estrogênios/metabolismo , Glândulas Exócrinas/ultraestrutura , Feminino , Masculino , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Reprodução , Ovinos/anatomia & histologia , Ovinos/metabolismo , Útero/metabolismo
19.
Mol Oncol ; 8(3): 753-65, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24656965

RESUMO

Despite the wide acceptance that glycans are centrally implicated in immunity, exactly how they contribute to the tilt immune response remains poorly defined. In this study, we sought to evaluate the impact of the malignant phenotype-associated glycan, sialyl-Tn (STn) in the function of the key orchestrators of the immune response, the dendritic cells (DCs). In high grade bladder cancer tissue, the STn antigen is significantly overexpressed and correlated with the increased expression of ST6GALNAC1 sialyltransferase. Bladder cancer tissue presenting elevated expression of ST6GALNAC1 showed a correlation with increased expression of CD1a, a marker for bladder immature DCs and showed concomitant low levels of Th1-inducing cytokines IL-12 and TNF-α. In vitro, human DCs co-incubated with STn(+) bladder cancer cells, had an immature phenotype (MHC-II(low), CD80(low) and CD86(low)) and were unresponsive to further maturation stimuli. When contacting with STn(+) cancer cells, DCs expressed significantly less IL-12 and TNF-α. Consistent with a tolerogenic DC profile, T cells that were primed by DCs pulsed with antigens derived from STn(+) cancer cells were not activated and showed a FoxP3(high) IFN-γ(low) phenotype. Blockade of STn antigens and of STn(+) glycoprotein, CD44 and MUC1, in STn(+) cancer cells was able to lower the induction of tolerance and DCs become more mature. Overall, our data suggest that STn-expressing cancer cells impair DC maturation and endow DCs with a tolerogenic function, limiting their capacity to trigger protective anti-tumour T cell responses. STn antigens and, in particular, STn(+) glycoproteins are potential targets for circumventing tumour-induced tolerogenic mechanisms.


Assuntos
Antígenos Glicosídicos Associados a Tumores/imunologia , Células Dendríticas/imunologia , Linfócitos T/imunologia , Neoplasias da Bexiga Urinária/imunologia , Idoso , Idoso de 80 Anos ou mais , Antígenos Glicosídicos Associados a Tumores/análise , Linhagem Celular Tumoral , Células Cultivadas , Células Dendríticas/patologia , Humanos , Receptores de Hialuronatos/análise , Receptores de Hialuronatos/imunologia , Imunidade Inata , Pessoa de Meia-Idade , Fagocitose , Linfócitos T/patologia , Bexiga Urinária/imunologia , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia
20.
Biol Blood Marrow Transplant ; 19(5): 703-12, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23396243

RESUMO

Haploidentical hematopoietic stem cell transplantation (HSCT) constitutes an important alternative for patients lacking a human leukocyte antigen (HLA)-matched donor. Although the use of haploidentical donors is increasingly common, the long-term impact of generating a donor-derived immune system in the context of an HLA-mismatched thymic environment remains poorly characterized. We performed an in-depth assessment of immune reconstitution in a group of haploidentical HSCT recipients 4 to 6 years posttransplantation, in parallel with the respective parental donors and age-matched healthy control subjects. Our data show that the proportion of naive and memory subsets in the recipients, both within CD8(+) and CD4(+) T cells, more closely resembled that observed in age-matched control subjects than in the donors. HSCT recipients displayed relatively high signal-joint T cell-receptor excision circle levels and a high frequency of the recent thymic emigrant-enriched CD31(+) subset within naive CD4(+) and naive regulatory T cells. Moreover, CD8(+), CD4(+), and regulatory T cells from HSCT recipients displayed a diverse T cell repertoire. These results support a key role for thymic output in T cell reconstitution. Nevertheless, HSCT recipients had significantly shorter telomeres within a naive-enriched CD4(+) T cell population than age-matched control subjects, despite the similar telomere length observed within the most differentiated CD8(+) and CD4(+) T cell subsets. Overall, our data suggest that long-term immune reconstitution was successfully achieved after haploidentical HSCT, a process that appears to have largely relied on de novo T cell production.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Subpopulações de Linfócitos T/imunologia , Adulto , Anemia Aplástica/imunologia , Anemia Aplástica/cirurgia , Estudos Transversais , Feminino , Haploidia , Humanos , Memória Imunológica , Leucemia/imunologia , Leucemia/cirurgia , Masculino , Pessoa de Meia-Idade , Doadores de Tecidos , Imunologia de Transplantes , Transplante Homólogo , Adulto Jovem
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