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1.
Transplant Cell Ther ; 28(8): 483.e1-483.e7, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35643351

RESUMO

Natural killer cell alloreactivity is determined by killer cell immunoglobulin-like receptor (KIR) ligands in donor and recipient pairs. A small, single institution study suggested that the risk of primary graft failure after cord blood hematopoietic cell transplantation (CBT) can be predicted by host-versus-graft (HvG)-directed natural killer cell alloreactivity. In the haploidentical transplantation (Haplo HCT) cohort, graft failures were observed only in graft-versus-host (GvH) KIR ligand mismatched pairs. A subsequent study was designed to explore the association between HvG and GvH KIR ligand mismatching and engraftment in both CBT and Haplo HCT using the large, multicenter transplant population of the Center for International Blood and Transplant Research database. Nine hundred single CBT (sCBT), 954 double CBT (dCBT), and 671 Haplo HCT performed between 2008 and 2017 for acute leukemias and myelodysplastic syndrome were examined. Several models of KIR-L interactions were analyzed by multiple regression analyses for their association with engraftment, overall survival (OS), and transplant-related mortality (TRM). In sCBT, although HvG or bidirectional KIR ligand mismatch (KIR-L-MM) was initially associated with higher TRM in the first 6 months after transplantation, this effect was nullified after 6 months such that long-term survival was not different compared to GvH KIR-L-MM or KIR-L matched (KIR-L-M) pairs. There was no significant difference in neutrophil and platelet engraftment. In dCBT, no significant differences were seen in engraftment, OS and TRM. In the Haplo cohort there was faster platelet recovery in the GvH KIR-L-MM/KIR-L-M pairs versus HvG KIR-L-MM or bidirectional mismatch (HR 1.23, P= .0116). There was no significant association with OS, TRM, or neutrophil engraftment. In this large registry study, KIR-L mismatching did not significantly impact engraftment, TRM, or survival in CBT and Haplo HCT, although an association with platelet engraftment in Haplo HCT was demonstrated.


Assuntos
Sangue Fetal , Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais , Antígenos de Histocompatibilidade/imunologia , Humanos , Células Matadoras Naturais/imunologia , Ligantes , Receptores KIR/imunologia
2.
BMC Cancer ; 22(1): 9, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34980000

RESUMO

PURPOSE: We sought to understand the clinical course and molecular phenotype of patients who showed disease progression after programmed cell death ligand 1 (PD-L1) inhibitor treatment but subsequently responded to PD-1 inhibitor treatment. We also explored the response to PD-1-axis targeted therapy of classical Hodgkin lymphoma (cHL) according to genetically driven PD-L1 and programmed cell death ligand 2 (PD-L2) expression. METHODS: Five patients in a phase II clinical trial of CS1001 (PD-L1 inhibitor) for relapsed or refractory (R/R) cHL were retrospectively reviewed. Formalin-fixed, paraffin-embedded whole tissues from the five patients were evaluated for 9p24.1 genetic alterations based on FISH and the expression of PD-L1, PD-L2, PD-1, major histocompatibility complex (MHC) class I-II, and the tumor microenvironment factorsCD163 and FOXP3 in the microenvironmental niche, as revealed by multiplex immunofluorescence. RESULTS: All five patients showed primary refractory disease during first-line treatment. Four patients received PD-1 inhibitor after dropping out of the clinical trial, and all demonstrated at least a partial response. The progression-free survival ranged from 7 to 28 months (median = 18 months), and 9p24.1 amplification was observed in all five patients at the PD-L1/PD-L2 locus. PD-L1 and PD-L2 were colocalized on Hodgkin Reed-Sternberg (HRS) cells in four of the five (80%) patients. There was differential expression of PD-L1 and PD-L2 in cells in the tumor microenvironment in cHL, especially in HRS cells, background cells and tumor-associated macrophages. CONCLUSIONS: PD-L1 monotherapy may not be sufficient to block the PD-1 pathway; PD-L2 was expressed in HRS and background cells in cHL. The immunologic function of the PD-L2 pathway in anti-tumor activity may be underestimated in R/R cHL. Further study is needed to elucidate the anti-tumor mechanism of PD-1 inhibitor and PD-L1 inhibitor treatment.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Doença de Hodgkin/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteína 2 Ligante de Morte Celular Programada 1/antagonistas & inibidores , Adulto , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Ensaios Clínicos Fase II como Assunto , Feminino , Fatores de Transcrição Forkhead/imunologia , Antígenos de Histocompatibilidade/imunologia , Doença de Hodgkin/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/imunologia , Intervalo Livre de Progressão , Receptores de Superfície Celular/imunologia , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Microambiente Tumoral/imunologia
3.
Eur J Immunol ; 52(2): 197-203, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34609741

RESUMO

Genome-wide association studies (GWAS) have identified many genes that are associated with the development of certain autoimmune disorders, but the MHC haplotypes still represent the most prevalent genetic risk factor for many autoimmune diseases. The mechanisms by which MHC-associated genetic susceptibility translates into B cell autoimmunity and the development of autoimmune diseases are complex. There is increasing evidence that the MHC haplotype modulates autoreactive B cell responses in multiple ways. Instead of merely inhibiting the production of IgG autoantibodies and mediating complete immunological tolerance, the non-permitting MHC haplotypes seem to facilitate the production of IgG autoantibodies exhibiting Fc glycosylation patterns that are associated with reduced pathogenicity and a protective cytokine profile of T follicular helper (Tfh) cells. Here, we discuss mechanisms linking MHC haplotypes to the production of pathogenic IgG autoantibodies, which could be relevant for the development of improved diagnosis, particularly in the context of individual medicine.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Linfócitos B/imunologia , Haplótipos/imunologia , Antígenos de Histocompatibilidade/imunologia , Imunoglobulina G/imunologia , Animais , Autoanticorpos/genética , Doenças Autoimunes/genética , Glicosilação , Antígenos de Histocompatibilidade/genética , Humanos , Imunoglobulina G/genética , Linfócitos T Auxiliares-Indutores/imunologia
4.
Front Immunol ; 12: 777788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868047

RESUMO

T cell receptors (TCRs) are unique markers that define antigen specificity for a given T cell. With the evolution of sequencing and computational analysis technologies, TCRs are now prime candidates for the development of next-generation non-cell based T cell biomarkers, which provide a surrogate measure to assess the presence of antigen-specific T cells. Type 1 diabetes (T1D), the immune-mediated form of diabetes, is a prototypical organ specific autoimmune disease in which T cells play a pivotal role in targeting pancreatic insulin-producing beta cells. While the disease is now predictable by measuring autoantibodies in the peripheral blood directed to beta cell proteins, there is an urgent need to develop T cell markers that recapitulate T cell activity in the pancreas and can be a measure of disease activity. This review focuses on the potential and challenges of developing TCR biomarkers for T1D. We summarize current knowledge about TCR repertoires and clonotypes specific for T1D and discuss challenges that are unique for autoimmune diabetes. Ultimately, the integration of large TCR datasets produced from individuals with and without T1D along with computational 'big data' analysis will facilitate the development of TCRs as potentially powerful biomarkers in the development of T1D.


Assuntos
Biomarcadores , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/metabolismo , Suscetibilidade a Doenças , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Alelos , Animais , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/terapia , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Predisposição Genética para Doença , Variação Genética , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Humanos , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Peptídeos/imunologia , Peptídeos/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia
5.
Front Immunol ; 12: 769799, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745146

RESUMO

Tumor Associated Antigens (TAAs) may suffer from an immunological tolerance due to expression on normal cells. In order to potentiate their immunogenicity, heteroclitic peptides (htcPep) were designed according to prediction algorithms. In particular, specific modifications were introduced in peptide residues facing to TCR. Moreover, a MHC-optimized scaffold was designed for improved antigen presentation to TCR by H-2Db allele. The efficacy of such htcPep was assessed in C57BL/6 mice injected with syngeneic melanoma B16F10 or lung TC1 tumor cell lines, in combination with metronomic chemotherapy and immune checkpoint inhibitors. The immunogenicity of htcPep was significantly stronger than the corresponding wt peptide and the modification involving both MHC and TCR binding residues scored the strongest. In particular, the H-2Db-specific scaffold significantly potentiated the peptides' immunogenicity and control of tumor growth was comparable to wt peptide in a therapeutic setting. Overall, we demonstrated that modified TAAs show higher immunogenicity compared to wt peptide. In particular, the MHC-optimized scaffold can present different antigen sequences to TCR, retaining the conformational characteristics of the corresponding wt. Cross-reacting CD8+ T cells are elicited and efficiently kill tumor cells presenting the wild-type antigen. This novel approach can be of high clinical relevance in cancer vaccine development.


Assuntos
Apresentação de Antígeno/imunologia , Vacinas Anticâncer/imunologia , Antígenos de Histocompatibilidade/imunologia , Neoplasias Experimentais/imunologia , Peptídeos/imunologia , Vacinas de Subunidades/imunologia , Animais , Apresentação de Antígeno/efeitos dos fármacos , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer/administração & dosagem , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Humanos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/prevenção & controle , Peptídeos/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/imunologia , Vacinas de Subunidades/administração & dosagem
6.
Front Immunol ; 12: 742881, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650566

RESUMO

Despite the high number of individuals infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who develop coronavirus disease 2019 (COVID-19) symptoms worldwide, many exposed individuals remain asymptomatic and/or uninfected and seronegative. This could be explained by a combination of environmental (exposure), immunological (previous infection), epigenetic, and genetic factors. Aiming to identify genetic factors involved in immune response in symptomatic COVID-19 as compared to asymptomatic exposed individuals, we analyzed 83 Brazilian couples where one individual was infected and symptomatic while the partner remained asymptomatic and serum-negative for at least 6 months despite sharing the same bedroom during the infection. We refer to these as "discordant couples". We performed whole-exome sequencing followed by a state-of-the-art method to call genotypes and haplotypes across the highly polymorphic major histocompatibility complex (MHC) region. The discordant partners had comparable ages and genetic ancestry, but women were overrepresented (65%) in the asymptomatic group. In the antigen-presentation pathway, we observed an association between HLA-DRB1 alleles encoding Lys at residue 71 (mostly DRB1*03:01 and DRB1*04:01) and DOB*01:02 with symptomatic infections and HLA-A alleles encoding 144Q/151R with asymptomatic seronegative women. Among the genes related to immune modulation, we detected variants in MICA and MICB associated with symptomatic infections. These variants are related to higher expression of soluble MICA and low expression of MICB. Thus, quantitative differences in these molecules that modulate natural killer (NK) activity could contribute to susceptibility to COVID-19 by downregulating NK cell cytotoxic activity in infected individuals but not in the asymptomatic partners.


Assuntos
Infecções Assintomáticas , COVID-19 , Antígenos de Histocompatibilidade , Complexo Principal de Histocompatibilidade , SARS-CoV-2 , Adulto , Idoso , Brasil , COVID-19/genética , COVID-19/imunologia , Feminino , Predisposição Genética para Doença , Genótipo , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Humanos , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Pessoa de Meia-Idade , Sequenciamento do Exoma
7.
Mol Neurobiol ; 58(12): 6111-6120, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34453271

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the pandemic of coronavirus disease (COVID-19). Whereas in most cases COVID-19 is asymptomatic or pauci-symptomatic, extremely severe clinical forms are observed. In this case, complex immune dysregulations and an excessive inflammatory response are reported and are the main cause of morbidity and mortality. Natural killer cells are key players in the control of viral infection, and their activity is regulated by a tight balance between activating and inhibitory receptors; an alteration of NK activity was suggested to be associated with the development of severe forms of COVID-19. In this study, we analyzed peripheral NK cell subpopulations and the expression of activating and inhibitory receptors in 30 patients suffering from neurological conditions who recovered from mild, moderate, or severe SARS-CoV-2 infection, comparing the results to those of 10 SARS-CoV-2-uninfected patients. Results showed that an expansion of NK subset with lower cytolytic activity and an augmented expression of the 2DL1 inhibitory receptor, particularly when in association with the C2 ligand (KIR2DL1-C2), characterized the immunological scenario of severe COVID-19 infection. An increase of NK expressing the ILT2 inhibitory receptor was instead seen in patients recovering from mild or moderate infection compared to controls. Results herein suggest that the KIR2DL1-C2 NK inhibitory complex is a risk factor toward the development of severe form of COVID-19. Our results confirm that a complex alteration of NK activity is present in COVID-19 infection and offer a molecular explanation for this observation.


Assuntos
COVID-19/imunologia , Células Matadoras Naturais/imunologia , Receptores KIR/metabolismo , Linfócitos B/imunologia , COVID-19/fisiopatologia , Antígenos de Histocompatibilidade/imunologia , Humanos , Ligantes , Subpopulações de Linfócitos/imunologia , Linfócitos T/imunologia
8.
Front Immunol ; 12: 705140, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34326847

RESUMO

Antibody-mediated allograft rejection (AMR) causes more kidney transplant failure than any other single cause. AMR is mediated by antibodies recognizing antigens expressed by the graft, and antibodies generated against major histocompatibility complex (MHC) mismatches are especially problematic. Most research directed towards the management of clinical AMR has focused on identifying and characterizing circulating donor-specific HLA antibody (DSA) and optimizing therapies that reduce B-cell activation and/or block antibody secretion by inhibiting plasmacyte survival. Here we describe a novel set of reagents and techniques to allow more specific measurements of MHC sensitization across different animal transplant models. Additionally, we have used these approaches to isolate and clone individual HLA-specific B cells from patients sensitized by pregnancy or transplantation. We have identified and characterized the phenotypes of individual HLA-specific B cells, determined the V(D)J rearrangements of their paired H and L chains, and generated recombinant antibodies to determine affinity and specificity. Knowledge of the BCR genes of individual HLA-specific B cells will allow identification of clonally related B cells by high-throughput sequence analysis of peripheral blood mononuclear cells and permit us to re-construct the origins of HLA-specific B cells and follow their somatic evolution by mutation and selection.


Assuntos
Subpopulações de Linfócitos B/imunologia , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Memória Imunológica , Isoanticorpos/sangue , Animais , Especificidade de Anticorpos , Linhagem Celular , Células Cultivadas , Evolução Clonal , Células Clonais , Feminino , Rearranjo Gênico do Linfócito B , Genes Reporter , Antígenos de Histocompatibilidade/biossíntese , Antígenos de Histocompatibilidade/imunologia , Humanos , Imunoglobulina G/imunologia , Indicadores e Reagentes , Isoanticorpos/imunologia , Ativação Linfocitária , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , RNA Guia de Cinetoplastídeos/genética , Transplante de Pele , Especificidade da Espécie , Organismos Livres de Patógenos Específicos , Recombinação V(D)J , Microglobulina beta-2/antagonistas & inibidores , Microglobulina beta-2/genética
9.
Front Immunol ; 12: 686127, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177934

RESUMO

T cell receptor (TCR) recognition of peptides presented by major histocompatibility complex (MHC) molecules is a fundamental process in the adaptive immune system. An understanding of this recognition process at the molecular level is crucial for TCR based therapeutics and vaccine design. The broad nature of TCR diversity and cross-reactivity presents a challenge for traditional structural resolution. Computational modelling of TCR-pMHC complexes offers an efficient alternative. This study compares the ability of four general-purpose docking platforms (ClusPro, LightDock, ZDOCK and HADDOCK) to make use of varying levels of binding interface information for accurate TCR-pMHC modelling. Each platform was tested on an expanded benchmark set of 44 TCR-pMHC docking cases. In general, HADDOCK is shown to be the best performer. Docking strategy guidance is provided to obtain the best models for each platform for future research. The TCR-pMHC docking cases used in this study can be downloaded from https://github.com/innate2adaptive/ExpandedBenchmark.


Assuntos
Biologia Computacional/métodos , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/metabolismo , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/metabolismo , Algoritmos , Antígenos de Histocompatibilidade/imunologia , Simulação de Acoplamento Molecular , Peptídeos/química , Peptídeos/imunologia , Peptídeos/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia
10.
Nat Commun ; 12(1): 2502, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947864

RESUMO

Mechanical forces acting on ligand-engaged T-cell receptors (TCRs) have previously been implicated in T-cell antigen recognition, yet their magnitude, spread, and temporal behavior are still poorly defined. We here report a FRET-based sensor equipped either with a TCR-reactive single chain antibody fragment or peptide-loaded MHC, the physiological TCR-ligand. The sensor was tethered to planar glass-supported lipid bilayers (SLBs) and informed most directly on the magnitude and kinetics of TCR-imposed forces at the single molecule level. When confronting T-cells with gel-phase SLBs we observed both prior and upon T-cell activation a single, well-resolvable force-peak of approximately 5 pN and force loading rates on the TCR of 1.5 pN per second. When facing fluid-phase SLBs instead, T-cells still exerted tensile forces yet of threefold reduced magnitude and only prior to but not upon activation.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Antígenos de Histocompatibilidade/química , Receptores de Antígenos de Linfócitos T/química , Imagem Individual de Molécula/métodos , Anticorpos de Cadeia Única/química , Animais , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/química , Linfócitos T CD8-Positivos/imunologia , Citocromos c/química , Transferência Ressonante de Energia de Fluorescência/instrumentação , Antígenos de Histocompatibilidade/imunologia , Cinética , Ligantes , Bicamadas Lipídicas/química , Camundongos , Peptídeos/química , Receptores de Antígenos de Linfócitos T/imunologia , Imagem Individual de Molécula/instrumentação , Anticorpos de Cadeia Única/imunologia , Análise Espaço-Temporal
11.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33979434

RESUMO

Experimentally estimating peptide-major histocompatibility complex (pMHC) binding affinity has been quite challenging due to the many receptors and the many potential ligands implicated in it. We have thus proposed a straightforward computational methodology considering the different mechanisms involved in pMHC binding to facilitate studying such receptor-ligand interactions. We have developed a pipeline using semi-empirical quantum mechanical methods for calculating pMHC class I and II molecules' binding energy (BE). This pipeline can systematize the methodology for calculating pMHC system BE, enabling the rational design of T-cell epitopes to be used as pharmaceuticals and vaccines.


Assuntos
Biologia Computacional/métodos , Antígenos de Histocompatibilidade/química , Modelos Moleculares , Oligopeptídeos/química , Teoria Quântica , Software , Algoritmos , Sequência de Aminoácidos , Antígenos de Histocompatibilidade/imunologia , Antígenos de Histocompatibilidade/metabolismo , Humanos , Ligantes , Oligopeptídeos/imunologia , Oligopeptídeos/metabolismo , Ligação Proteica , Relação Estrutura-Atividade
12.
Mol Ther ; 29(2): 718-733, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33554868

RESUMO

Allogeneic, off-the-shelf (OTS) chimeric antigen receptor (CAR) cell therapies have the potential to reduce manufacturing costs and variability while providing broader accessibility to cancer patients and those with other diseases. However, host-versus-graft reactivity can limit the durability and efficacy of OTS cell therapies requiring new strategies to evade adaptive and innate-immune responses. Human herpes virus-8 (HHV8) maintains infection, in part, by evading host T and natural killer (NK) cell attack. The viral K3 gene encodes a membrane-tethered E3 ubiquitin ligase that discretely targets major histocompatibility complex (MHC) class I components, whereas K5 encodes a similar E3 ligase with broader specificity, including MHC-II and the MHC-like MHC class I polypeptide-related sequence A (MIC-A)- and sequence B (MIC-B)-activating ligands of NK cells. We created γ-retroviruses encoding K3 and/or K5 transgenes that efficiently transduce primary human T cells. Expression of K3 or K5 resulted in dramatic downregulation of MHC-IA (human leukocyte antigen [HLA]-A, -B, and -C) and MHC class II (HLA-DR) cell-surface expression. K3 expression was sufficient for T cells to resist exogenously loaded peptide-MHC-specific cytotoxicity, as well as recognition in one-way allogeneic mixed lymphocyte reactions. Further, in immunodeficient mice engrafted with allogeneic T cells, K3-transduced T cells selectively expanded in vivo. Ectopic K5 expression in MHC class I-, MIC-A+/B+ K562 cells also reduced targeting by primary NK cells. Coexpression of K3 in prostate stem cell antigen (PSCA)-directed, inducible MyD88/CD40 (iMC)-enhanced CAR-T cells did not impact cytotoxicity, T cell growth, or cytokine production against HPAC pancreatic tumor target cells, whereas K5-expressing cells showed a modest reduction in interleukin (IL)-2 production without effect on cytotoxicity. Together, these results support application of these E3 ligases to advance development of OTS CAR-T cell products.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Engenharia Genética , Herpesvirus Humano 8/imunologia , Antígenos de Histocompatibilidade/imunologia , Imunoterapia Adotiva , Proteínas Virais/imunologia , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Modelos Animais de Doenças , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Allergy Clin Immunol ; 147(6): 2030-2042, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33259837

RESUMO

γδ T cells are much less common than αß T cells, accounting for 0.5% to 5% of all T lymphocytes in the peripheral blood and lymphoid tissues in mice and humans. However, they are the most abundant T-lymphocyte subset in some epithelial barriers such as mouse skin. γδ T cells are considered innate lymphocytes because of their non-MHC restricted antigen recognition, as well as because of their rapid response to cytokines, invading pathogens, and malignant cells. Exacerbated expansion and activation of γδ T cells in the skin is a common feature of acute and chronic skin inflammation such as psoriasis and contact or atopic dermatitis. Different γδ T-cell subsets showing differential developmental and functional features are found in mouse and human skin. This review discusses the state of the art of research and future perspectives about the role of the different subsets of γδ T-cells detected in the skin in steady-state, psoriasis, dermatitis, infection, and malignant skin diseases. Also, we highlight the differences between human and mouse γδ T cells in skin homeostasis and inflammation, as understanding the differential role of each subtype of skin γδ T cells will improve the discovery of new therapies.


Assuntos
Suscetibilidade a Doenças , Homeostase , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Pele/imunologia , Pele/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Animais , Biomarcadores , Dermatite/etiologia , Dermatite/metabolismo , Dermatite/patologia , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Humanos , Pele/patologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
14.
Front Immunol ; 12: 804988, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35173709

RESUMO

Recently, many reports were published supporting the clinical use of adoptively transferred natural killer (NK) cells as a therapeutic tool against cancer, including acute myeloid leukemia (AML). Our group demonstrated promising clinical response using adoptive immunotherapy with donor-derived alloreactive KIR-ligand-mismatched NK cells in AML patients. Moreover, the antileukemic effect was correlated with the dose of infused alloreactive NK cells ("functional NK cell dose"). Herein, we update the results of our previous study on a cohort of adult AML patients (median age at enrollment 64) in first morphological complete remission (CR), not eligible for allogeneic stem cell transplantation. After an extended median follow-up of 55.5 months, 8/16 evaluable patients (50%) are still off-therapy and alive disease-free. Overall survival (OS) and disease-free survival (DFS) are related with the dose of infused alloreactive NK cells (≥2 × 105/kg).


Assuntos
Imunoterapia Adotiva/métodos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Idoso , Feminino , Antígenos de Histocompatibilidade/imunologia , Teste de Histocompatibilidade , Humanos , Imunoterapia Adotiva/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
15.
Front Immunol ; 12: 784359, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095857

RESUMO

Marek's disease virus (MDV), the etiologic agent for Marek's disease (MD), causes a deadly lymphoproliferative disease in chickens. Causes of the well-documented association between genetically defined lines of chicken and resistance to MD remain unknown. Here, the frequencies of IFN-gamma producing pp38 and MEQ-specific T cell responses were determined in line N (B21 haplotype; MD-resistant) and line P2a (B19 haplotype, MD-susceptible) chickens after infection with vaccine and/or virulent (RB1B) strains of MDV using both standard ex vivo and cultured chIFN-gamma ELISPOT assays. Notably, MDV infection of naïve and vaccinated MD-resistant chickens induced higher frequencies of IFN-gamma producing MDV-specific T cell responses using the cultured and ex vivo ELISPOT assay, respectively. Remarkably, vaccination did not induce or boost MEQ-specific effector T cells in the susceptible chickens, while it boosted both pp38-and MEQ-specific response in resistant line. Taken together, our results revealed that there is a direct association between the magnitude of T cell responses to pp38 and MEQ of MDV antigens and resistance to the disease.


Assuntos
Galinhas/imunologia , Haplótipos/imunologia , Antígenos de Histocompatibilidade/imunologia , Interferon gama/imunologia , Mardivirus/imunologia , Doença de Marek/imunologia , Linfócitos T/imunologia , Animais , Galinhas/virologia , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/virologia , Doença de Marek/virologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Virulência/imunologia
16.
Mucosal Immunol ; 14(1): 68-79, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483197

RESUMO

Thymocytes bearing αß T cell receptors (TCRαß) with high affinity for self-peptide-MHC complexes undergo negative selection or are diverted to alternate T cell lineages, a process termed agonist selection. Among thymocytes bearing TCRs restricted to MHC class I, agonist selection can lead to the development of precursors that can home to the gut and give rise to CD8αα-expressing intraepithelial lymphocytes (CD8αα IELs). The factors that influence the choice between negative selection versus CD8αα IEL development remain largely unknown. Using a synchronized thymic tissue slice model that supports both negative selection and CD8αα IEL development, we show that the affinity threshold for CD8αα IEL development is higher than for negative selection. We also investigate the impact of peptide presenting cells and cytokines, and the migration patterns associated with these alternative cell fates. Our data highlight the roles of TCR affinity and the thymic microenvironments on T cell fate.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Seleção Clonal Mediada por Antígeno , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Timo/imunologia , Timo/metabolismo , Linfócitos T CD8-Positivos/citologia , Microambiente Celular , Seleção Clonal Mediada por Antígeno/genética , Seleção Clonal Mediada por Antígeno/imunologia , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Linfócitos Intraepiteliais/citologia , Peptídeos/imunologia , Timo/citologia
17.
Viruses ; 12(12)2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256093

RESUMO

Alphaherpesviruses cause various diseases and establish life-long latent infections in humans and animals. These viruses encode multiple viral proteins and miRNAs to evade the host immune response, including both innate and adaptive immunity. Alphaherpesviruses evolved highly advanced immune evasion strategies to be able to replicate efficiently in vivo and produce latent infections with recurrent outbreaks. This review describes the immune evasion strategies of alphaherpesviruses, especially against cytotoxic host immune responses. Considering these strategies, it is important to evaluate whether the immune evasion mechanisms in cell cultures are applicable to viral propagation and pathogenicity in vivo. This review focuses on cytotoxic T lymphocytes (CTLs), natural killer cells (NK cells), and natural killer T cells (NKT cells), which are representative immune cells that directly damage virus-infected cells. Since these immune cells recognize the ligands expressed on their target cells via specific activating and/or inhibitory receptors, alphaherpesviruses make several ligands that may be targets for immune evasion. In addition, alphaherpesviruses suppress the infiltration of CTLs by downregulating the expression of chemokines at infection sites in vivo. Elucidation of the alphaherpesvirus immune evasion mechanisms is essential for the development of new antiviral therapies and vaccines.


Assuntos
Alphaherpesvirinae/fisiologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Imunidade Celular , Animais , Apresentação de Antígeno , Biomarcadores , Citocinas/metabolismo , Infecções por Herpesviridae/metabolismo , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Interações Hospedeiro-Patógeno/genética , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo
18.
Immunity ; 53(6): 1182-1201.e8, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33242395

RESUMO

αß lineage T cells, most of which are CD4+ or CD8+ and recognize MHC I- or MHC II-presented antigens, are essential for immune responses and develop from CD4+CD8+ thymocytes. The absence of in vitro models and the heterogeneity of αß thymocytes have hampered analyses of their intrathymic differentiation. Here, combining single-cell RNA and ATAC (chromatin accessibility) sequencing, we identified mouse and human αß thymocyte developmental trajectories. We demonstrated asymmetric emergence of CD4+ and CD8+ lineages, matched differentiation programs of agonist-signaled cells to their MHC specificity, and identified correspondences between mouse and human transcriptomic and epigenomic patterns. Through computational analysis of single-cell data and binding sites for the CD4+-lineage transcription factor Thpok, we inferred transcriptional networks associated with CD4+- or CD8+-lineage differentiation, and with expression of Thpok or of the CD8+-lineage factor Runx3. Our findings provide insight into the mechanisms of CD4+ and CD8+ T cell differentiation and a foundation for mechanistic investigations of αß T cell development.


Assuntos
Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Subpopulações de Linfócitos T/imunologia , Timócitos/imunologia , Animais , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Epigenoma , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Antígenos de Histocompatibilidade/metabolismo , Humanos , Camundongos , Subpopulações de Linfócitos T/metabolismo , Timócitos/metabolismo , Timo/imunologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
19.
Front Immunol ; 11: 576651, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042160

RESUMO

Strategies targeting T cells are the cornerstone of immunosuppression after solid organ transplantation. The transcription factor NF-κB is a key regulator of downstream T-cell activation and induction of inflammatory mediators; its full activation via antigen receptor engagement requires both the scaffold and the protease activity of the paracaspase Malt1. Experimental studies have highlighted that Malt1-deficient mice were resistant to experimental autoimmune encephalomyelitis, although they lacked peripheral regulatory T cells (Treg). Here, we compared targeting Malt1 versus using calcineurin inhibitors as immunosuppression in a stringent experimental transplantation model. We found that Malt1-deficiency impaired Th1-mediated alloresponses in vitro and in vivo and significantly prolonged MHC-mismatched skin allograft survival, compared to cyclosporine. However, it paradoxically enhanced Th17 differentiation in the transplantation setting. Interestingly, more selective inhibition of Malt1 protease activity in wild-type mouse and human peripheral T cells in vitro led to attenuation of alloreactive Th1 cells, while preserving preexisting Treg in the peripheral T-cell pool, and without promoting Th17 differentiation. Thus, there is a place for further investigation of the role of Malt1 signaling in the setting of transplantation.


Assuntos
Rejeição de Enxerto/imunologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Transplante de Pele , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Aloenxertos/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Sobrevivência de Enxerto , Antígenos de Histocompatibilidade/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Terapia de Alvo Molecular , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , NF-kappa B/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
20.
PLoS One ; 15(9): e0239785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32976525

RESUMO

Porcine rubulavirus (PRV), which belongs to the family Paramyxoviridae, causes blue eye disease in pigs, characterized by encephalitis and reproductive failure in newborn and adult pigs, respectively. There is no effective treatment against PRV and no information on the effectiveness of the available vaccines. Continuous outbreaks have occurred in Mexico since the early 1980s, which have caused serious economic losses to pig producers. Vaccination can be used to control this disease. Searching for effective antigen candidates against PRV, we first sequenced the PAC1 F protein, then we used various immunoinformatics tools to predict antigenic determinants of B-cells and T-cells against the two glycoproteins of the virus (HN and F proteins). Finally, we used AutoDock Vina to determine the binding energies. We obtained the F gene sequence of a PRV strain collected in the early 1990s in Mexico and compared its amino acid profile with previous and more recent strains, obtaining an identity similarity of 97.78 to 99.26%. For the F proteins, seven linear B-cell epitopes, six conformational B-cell epitopes and twenty-nine T-cell MHC class I epitopes were predicted. For the HN proteins, sixteen linear B-cell epitopes, seven conformational B-cell epitopes and thirty-four T-cell MHC class I epitopes were predicted. The ATRSETDYY and AAYTTTTCF epitopes of the HN protein might be important for neutralizing the viral infection. We determined the in silico binding energy between the predicted epitopes on the F and HN proteins and swine MHC-I molecules. The binding energy of these epitopes ranged from -5.8 to -7.8 kcal/mol. The present study aimed to assess the use of HN and F proteins as antigens, either as recombinant proteins or as a series of peptides that could activate different responses of the immune system. This may help identify relevant immunogens, saving time and costs in the development of new vaccines or diagnostic tools.


Assuntos
Epitopos/química , Proteína HN/imunologia , Rubulavirus/imunologia , Proteínas Virais de Fusão/imunologia , Animais , Antígenos Virais/química , Antígenos Virais/imunologia , Chlorocebus aethiops , Biologia Computacional/métodos , Epitopos/imunologia , Proteína HN/química , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/imunologia , Suínos , Células Vero , Proteínas Virais de Fusão/química
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