RESUMO
The quality and quantity of tumor-infiltrating lymphocytes, particularly CD8+ T cells, are important parameters for the control of tumor growth and response to immunotherapy. Here, we show in murine and human cancers that these parameters exhibit circadian oscillations, driven by both the endogenous circadian clock of leukocytes and rhythmic leukocyte infiltration, which depends on the circadian clock of endothelial cells in the tumor microenvironment. To harness these rhythms therapeutically, we demonstrate that efficacy of chimeric antigen receptor T cell therapy and immune checkpoint blockade can be improved by adjusting the time of treatment during the day. Furthermore, time-of-day-dependent T cell signatures in murine tumor models predict overall survival in patients with melanoma and correlate with response to anti-PD-1 therapy. Our data demonstrate the functional significance of circadian dynamics in the tumor microenvironment and suggest the importance of leveraging these features for improving future clinical trial design and patient care.
Assuntos
Linfócitos T CD8-Positivos , Imunoterapia , Linfócitos do Interstício Tumoral , Camundongos Endogâmicos C57BL , Microambiente Tumoral , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Relógios Circadianos , Ritmo Circadiano , Células Endoteliais/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Melanoma/terapia , Melanoma/patologia , Microambiente Tumoral/imunologiaRESUMO
The metabolic challenges present in tumors attenuate the metabolic fitness and antitumor activity of tumor-infiltrating T lymphocytes (TILs). However, it remains unclear whether persistent metabolic insufficiency can imprint permanent T cell dysfunction. We found that TILs accumulated depolarized mitochondria as a result of decreased mitophagy activity and displayed functional, transcriptomic and epigenetic characteristics of terminally exhausted T cells. Mechanistically, reduced mitochondrial fitness in TILs was induced by the coordination of T cell receptor stimulation, microenvironmental stressors and PD-1 signaling. Enforced accumulation of depolarized mitochondria with pharmacological inhibitors induced epigenetic reprogramming toward terminal exhaustion, indicating that mitochondrial deregulation caused T cell exhaustion. Furthermore, supplementation with nicotinamide riboside enhanced T cell mitochondrial fitness and improved responsiveness to anti-PD-1 treatment. Together, our results reveal insights into how mitochondrial dynamics and quality orchestrate T cell antitumor responses and commitment to the exhaustion program.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Dinâmica Mitocondrial/imunologia , Biomarcadores , Epigênese Genética , Epigenômica , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Mitofagia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Niacinamida/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Estresse Fisiológico , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Depleting regulatory T cells (Treg cells) to counteract immunosuppressive features of the tumor microenvironment (TME) is an attractive strategy for cancer treatment; however, autoimmunity due to systemic impairment of their suppressive function limits its therapeutic potential. Elucidating approaches that specifically disrupt intratumoral Treg cells is direly needed for cancer immunotherapy. We found that CD36 was selectively upregulated in intrautumoral Treg cells as a central metabolic modulator. CD36 fine-tuned mitochondrial fitness via peroxisome proliferator-activated receptor-ß signaling, programming Treg cells to adapt to a lactic acid-enriched TME. Genetic ablation of Cd36 in Treg cells suppressed tumor growth accompanied by a decrease in intratumoral Treg cells and enhancement of antitumor activity in tumor-infiltrating lymphocytes without disrupting immune homeostasis. Furthermore, CD36 targeting elicited additive antitumor responses with anti-programmed cell death protein 1 therapy. Our findings uncover the unexplored metabolic adaptation that orchestrates the survival and functions of intratumoral Treg cells, and the therapeutic potential of targeting this pathway for reprogramming the TME.
Assuntos
Antígenos CD36/imunologia , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Apoptose/imunologia , Antígenos CD36/deficiência , Antígenos CD36/genética , Linhagem Celular Tumoral , Feminino , Homeostase/imunologia , Humanos , Imunoterapia , Metabolismo dos Lipídeos/genética , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/metabolismo , Neoplasias/patologia , PPAR beta/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Microambiente Tumoral/imunologiaRESUMO
The process of cancer immunosurveillance is a mechanism of tumour suppression that can protect the host from cancer development throughout its lifetime1,2. However, it is unknown whether the effectiveness of cancer immunosurveillance fluctuates over a single day. Here we demonstrate that the initial time of day of tumour engraftment dictates the ensuing tumour size across mouse cancer models. Using immunodeficient mice as well as mice lacking lineage-specific circadian functions, we show that dendritic cells (DCs) and CD8+ T cells exert circadian anti-tumour functions that control melanoma volume. Specifically, we find that rhythmic trafficking of DCs to the tumour draining lymph node governs a circadian response of tumour-antigen-specific CD8+ T cells that is dependent on the circadian expression of the co-stimulatory molecule CD80. As a consequence, cancer immunotherapy is more effective when synchronized with DC functions, shows circadian outcomes in mice and suggests similar effects in humans. These data demonstrate that the circadian rhythms of anti-tumour immune components are not only critical for controlling tumour size but can also be of therapeutic relevance.
Assuntos
Linfócitos T CD8-Positivos , Ritmo Circadiano , Células Dendríticas , Melanoma , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Imunoterapia/métodos , Melanoma/imunologia , Melanoma/patologia , Melanoma/terapia , Camundongos Endogâmicos C57BL , Antígeno B7-1 , Antígenos de Neoplasias/imunologia , Linfonodos , Ritmo Circadiano/imunologiaRESUMO
Group-2 innate lymphoid cells (ILC2s), which are involved in type 2 inflammatory diseases such as allergy, can exhibit immunological memory, but the basis of this ILC2 "trained immunity" has remained unclear. Here, we found that stimulation with IL-33/IL-25 or exposure to the allergen papain induces the expression of the transcription factor c-Maf in mouse ILC2s. Chronic papain exposure results in high production of IL-5 and IL-13 cytokines and lung eosinophil recruitment, effects that are blocked by c-Maf deletion in ILCs. Transcriptomic analysis revealed that knockdown of c-Maf in ILC2s suppresses expression of type 2 cytokine genes, as well as of genes linked to a memory-like phenotype. Consistently, c-Maf was found highly expressed in human adult ILC2s but absent in cord blood and required for cytokine production in isolated human ILC2s. Furthermore, c-Maf-deficient mouse or human ILC2s failed to exhibit strengthened ("trained") responses upon repeated challenge. Thus, the expression of c-Maf is indispensable for optimal type 2 cytokine production and proper memory-like responses in group-2 innate lymphoid cells.
Assuntos
Imunidade Inata , Linfócitos , Animais , Citocinas/metabolismo , Humanos , Interleucina-33/genética , Interleucina-33/metabolismo , Pulmão/metabolismo , Linfócitos/metabolismo , Camundongos , Papaína/metabolismo , Proteínas Proto-Oncogênicas c-maf/metabolismoRESUMO
BACKGROUND: Intravenous immunoglobulin (IVIg) has been used for almost 40 years in the treatment of autoimmune and systemic inflammatory diseases. Numerous cells are involved in the innate immune response, including monocytes/macrophages, neutrophils, dendritic cells, mast cells, basophils, eosinophils, natural killer cells, and innate lymphoid cells. Many studies have investigated the mechanisms by which IVIg down-modulates inflammatory and autoimmune processes of innate immune cells. However, questions remain regarding the precise mechanism of action in autoimmune or inflammatory conditions. The aim of this work was to review the immunomodulatory effect of IVIg on only human innate immune cells. A narrative review approach was chosen to summarize key evidence on the immunomodulatory effects of commercially available and unmodified IVIg on human innate immune cells. SUMMARY: Numerous different immunomodulatory effects of IVIg have been reported, with some very different effects depending on the immune cell type and disease. Several limitations of the different studies were identified. Of the 77 studies identified and reviewed, 29 (37.7%) dealt with autoimmune or inflammatory diseases. Otherwise, the immunomodulatory effects of IVIg were studied only in healthy donors using an in vitro experimental approach. Some of the documented effects showed disease-specific effects, such as in Kawasaki disease. Various methodological limitations have also been identified that may reduce the validity of some studies. KEY MESSAGE: As further insights have been gained into the various inflammatory cascades activated in immunological diseases, interesting insights have also been gained into the mechanism of action of IVIg. We are still far from discovering all the immunomodulatory mechanisms of IVIg.
RESUMO
Chronic myeloid leukemia (CML) is a hematologic malignancy associated to an unregulated growth of myeloid cells in bone marrow (BM) and peripheral blood (PB), characterized by the BCR-ABL1 translocation. Given the known cytokine impairment in the leukemic niche of CML, we investigated the impact of this microenvironmental dysregulation on innate lymphoid cells (ILC), whose role in cancer has recently emerged. Three ILC subsets are identified based on transcriptional profiles and cytokine secretion. We observed that interleukin 18 (IL-18) and vascular endothelial growth factor A (VEGF-A) are increased in CML patients' sera and that ILC2 are enriched in CML PB and BM. We found that IL-18 drives ILC2 proliferation and that CML ILC2 highly express CXCR4 and CXCR7 BM-homing receptors, potentially explaining their enrichment in PB and BM, respectively. Next, we showed that ILC2 are hyper-activated through a tumor-derived VEGF-Adependent mechanism, which leads to higher IL-13 secretion. In response to IL-13, leukemic cells increase their clonogenic capacity. Finally, we discovered that the pro-tumoral axis involving VEGF-A, IL-18 and ILC2 was disrupted upon tyrosine kinase inhibitor treatment, normalizing the levels of all these players in CML patients responding to therapy. Overall, our study uncovers the involvement of ILC2 in CML progression, mediated by VEGF-A and IL-18.
Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Fator A de Crescimento do Endotélio Vascular , Humanos , Imunidade Inata , Interleucina-18 , Proteínas de Fusão bcr-abl/metabolismo , Interleucina-13 , Linfócitos/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologiaRESUMO
Group 2 innate lymphoid cells (ILC2s) are critical for the initiation of type 2 inflammatory diseases. However, ILC2s are also involved in the establishment of the immune microenvironment during tumor development, growth and metastasization. In this context, ILC2s have been shown to be either tumor-suppressive or tumor-promoting according to the tumor type, the cytokine secreted and the other immune cells that are, in turn, recruited and/or activated.
Assuntos
Suscetibilidade a Doenças , Imunidade Inata , Linfócitos/imunologia , Linfócitos/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Animais , Citocinas/metabolismo , Humanos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Neoplasias/patologia , Microambiente Tumoral/imunologiaRESUMO
The role and regulation of innate immune cells is poorly understood in B-cell non-Hodgkin lymphoma (NHL). As natural killer (NK) cells, helper innate lymphoid cells (ILCs) are lymphocytes endowed with either anti- or pro-tumour activity and involved in inflammatory processes. In our ex vivo analysis of NK cells and ILCs from NHL patients, we observed that, in comparison to healthy donors (HD), the frequency of the cytotoxic subset of NK cells, the CD16+ NK, decreased in patients' peripheral blood. In general, circulating NK cells showed a pro-tumorigenic phenotype, while ILCs displayed a more activated/cytotoxic phenotype. Conversely, at the tumour site, in patients' lymph nodes, ILCs showed a low expression of granzyme.In vitromixed lymphocyte-tumour cell cultures with HD PBMCs and NHL cell lines demonstrated that ILC cytotoxic potential was lowered by the presence of tumour cells but, in the absence of T regulatory cells (Tregs), their cytolytic potential was recovered. Our data shed novel light on dysfunctional innate immunity in NHL. We suggest a new mechanism of tumour immuno-escape based on the reduction of cell cytotoxicity involving ILCs and likely controlled by Tregs.
Assuntos
Antineoplásicos , Linfoma não Hodgkin , Neoplasias , Humanos , Evasão Tumoral , Imunidade Inata , Linfócitos , Células Matadoras Naturais , Neoplasias/patologia , Linfoma não Hodgkin/patologiaRESUMO
Immune system failure in primary antibody deficiencies (PADs) has been linked to recurrent infections, autoimmunity, and cancer, yet clinical judgment is often based on the reactivity to a restricted panel of antigens. Previously, we demonstrated that the human repertoire of carbohydrate-specific immunoglobulin G (IgG) exhibits modular organization related to glycan epitope structure. The current study compares the glycan-specific IgG repertoires between different PAD entities. Distinct repertoire profiles with extensive qualitative glycan-recognition defects were observed, which are characterized by the common loss of Galα and GalNAc reactivity and disease-specific recognition of microbial antigens, self-antigens, and tumor-associated carbohydrate antigens. Antibody repertoire analysis may provide a useful tool to elucidate the degree and the clinical implications of immune system failure in individual patients.
Assuntos
Autoantígenos/imunologia , Carboidratos/imunologia , Epitopos/imunologia , Imunoglobulina G/imunologia , Doenças da Imunodeficiência Primária/imunologia , Feminino , Humanos , MasculinoRESUMO
Innate lymphoid cells (ILCs) consist of natural killer (NK) cells and non-cytotoxic ILCs that are broadly classified into ILC1, ILC2, and ILC3 subtypes. These cells recently emerged as important early effectors of innate immunity for their roles in tissue homeostasis and inflammation. Over the last few years, ILCs have been extensively studied in mouse and human at the functional and molecular level, including gene expression profiling. However, sorting ILCs with flow cytometry for gene expression analysis is a delicate and time-consuming process. Here we propose and validate a novel framework for studying ILCs at the transcriptomic level using single-cell RNA-Seq data. Our approach combines unsupervised clustering and a new cell type classifier trained on mouse ILC gene expression data. We show that this approach can accurately identify different ILCs, especially ILC2 cells, in human lymphocyte single-cell RNA-Seq data. Our new model relies only on genes conserved across vertebrates, thereby making it in principle applicable in any vertebrate species. Considering the rapid increase in throughput of single-cell RNA-Seq technology, our work provides a computational framework for studying ILC2 cells in single-cell transcriptomic data and may help exploring their conservation in distant vertebrate species.
Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Imunidade Inata/genética , Células Matadoras Naturais/metabolismo , Linfócitos/metabolismo , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Animais , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Humanos , Imunidade Inata/imunologia , Células Matadoras Naturais/imunologia , Linfócitos/classificação , Linfócitos/imunologia , CamundongosRESUMO
The degradation process of the antigens specific to MHC-I presentation depends mainly on the proteasomal proteases in the cytosol. However, since many antigens are glycoproteins, including tumor antigens or viruses envelope proteins, their glycosylation status could also affect their processing and presentation. Here, we investigate the processing of tyrosinase, a multiple glycosylated tumor antigen overexpressed in human malignant melanoma. By LC-MS/MS analysis of human tyrosinase expressed in a melanoma cell, we show that all seven sites of tyrosinase are at least partially N-glycosylated. Using human CD8+ T-cell clones specific for the tyrosinase epitope YMDGTMSQV (369-377), including an N-glycosylation site, we found that transfectants of single and triple N-glycosylation mutants are recognized by specific T cells. Importantly, single, triple, and the aglycosylated tyrosinase mutants lacking the epitope located N-glycosylation site (N371D) were able to trigger higher CD8+ T-cell activation. The LC/MS analysis showed significant increase of the amount of YMDGTMSQV peptide resulted from accelerated oligomerization and degradation of aglycosylated mutants. The generation of the antigenic peptide by the antigen processing machinery is therefore largely independent of tyrosinase N-glycosylation. However, while distal N-glycans had no effect on the epitope generation, the mutants lacking the N371 glycan generated the antigenic peptide more efficiently. We conclude that epitope located N-glycans limit the ability of human tyrosinase to provide HLA-A2-restricted antigen for recognition by specific CD8+ T cells.
Assuntos
Apresentação de Antígeno/imunologia , Epitopos , Antígenos de Histocompatibilidade Classe I/imunologia , Polissacarídeos/imunologia , Linfócitos T CD8-Positivos/imunologia , Glicosilação , Antígeno HLA-A2 , Humanos , Ativação Linfocitária/genética , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/imunologia , Proteínas MutantesRESUMO
Dendritic cells (DCs) are professional APCs that have a role in the initiation of adaptive immune responses and tolerance. Among the tolerogenic mechanisms, the expression of the enzyme IDO1 represents an effective tool to generate T regulatory cells. In humans, different DC subsets express IDO1, but less is known about the IDO1-related enzyme IDO2. In this study, we found a different pattern of expression and regulation between IDO1 and IDO2 in human circulating DCs. At the protein level, IDO1 is expressed only in circulating myeloid DCs (mDCs) and is modulated by PGE2, whereas IDO2 is expressed in both mDCs and plasmacytoid DCs and is not modulated by PGE2. In healthy subjects, IDO1 expression requires the presence of PGE2 and needs continuous transcription and translation, whereas IDO2 expression is constitutive, independent from suppressor of cytokine signaling 3 activity. Conversely, in patients suffering from inflammatory arthritis, circulating DCs express both IDO1 and IDO2. At the functional level, both mDCs and plasmacytoid DCs generate T regulatory cells through an IDO1/IDO2-dependent mechanism. We conclude that, in humans, whereas IDO1 provides an additional mechanism of tolerance induced by proinflammatory mediators, IDO2 is stably expressed in steady-state conditions and may contribute to the homeostatic tolerogenic capacity of DCs.
Assuntos
Células Dendríticas/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/fisiologia , Linfócitos T Reguladores/imunologia , Artrite Psoriásica/imunologia , Artrite Psoriásica/patologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Células Cultivadas , Células Dendríticas/classificação , Células Dendríticas/enzimologia , Dinoprostona/farmacologia , Dinoprostona/fisiologia , Indução Enzimática/efeitos dos fármacos , Homeostase , Humanos , Tolerância Imunológica , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Monócitos/citologia , Monócitos/efeitos dos fármacos , Especificidade de Órgãos , Biossíntese de Proteínas/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Espondilite Anquilosante/imunologia , Espondilite Anquilosante/patologia , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/antagonistas & inibidores , Transcrição Gênica/efeitos dos fármacos , Triptofano/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
Ex vivo ELISPOT and multimer staining are well-established tests for the assessment of antigen-specific T cells. Many laboratories are now using a period of in vitro stimulation (IVS) to enhance detection. Here, we report the findings of a multi-centre panel organised by the Association for Cancer Immunotherapy Immunoguiding Program to investigate the impact of IVS protocols on the detection of antigen-specific T cells of varying ex vivo frequency. Five centres performed ELISPOT and multimer staining on centrally prepared PBMCs from 3 donors, both ex vivo and following IVS. A harmonised IVS protocol was designed based on the best-performing protocol(s), which was then evaluated in a second phase on 2 donors by 6 centres. All centres were able to reliably detect antigen-specific T cells of high/intermediate frequency both ex vivo (Phase I) and post-IVS (Phase I and II). The highest frequencies of antigen-specific T cells ex vivo were mirrored in the frequencies following IVS and in the detection rates. However, antigen-specific T cells of a low/undetectable frequency ex vivo were not reproducibly detected post-IVS. Harmonisation of the IVS protocol reduced the inter-laboratory variation observed for ELISPOT and multimer analyses by approximately 20 %. We further demonstrate that results from ELISPOT and multimer staining correlated after (P < 0.0001 and R (2) = 0.5113), but not before IVS. In summary, IVS was shown to be a reproducible method that benefitted from method harmonisation.
Assuntos
Linfócitos T CD8-Positivos/citologia , ELISPOT/métodos , Antígenos HLA/química , Técnicas de Laboratório Clínico , Alemanha , Humanos , Leucócitos Mononucleares/imunologia , Países Baixos , Reprodutibilidade dos Testes , Coloração e Rotulagem , Suíça , Reino UnidoRESUMO
Tumor-infiltrating lymphocytes are present in a variety of tumors and play a central role in antitumor immune responses. Nevertheless, most cancers progress probably because tumors are only weakly immunogenic and develop multiple immunosuppressive mechanisms. In the present study, on head and neck squamous cell carcinoma, we found high intraepithelial infiltration of regulatory FOXP3(+) T cells, and relatively high levels of BDCA2(+) and FOXP3(+) cells in stromal (peripheral) regions of the tumors. Tumor-infiltrating (intraepithelial) FOXP3(+) T cells were significantly more frequent in patients with oropharynx and oral cavity squamous cell carcinoma and in patients without lymph node metastasis. Furthermore, arginase-II (ARG2) was expressed by 60%, inducible nitric oxide synthetase by 9%, cyclooxygenase-2 by 43%, and B-cell lymphoma 2 (BCL2) by 26% of tumors. Interestingly, the absence of ARG2 expression, enhanced stromal infiltration of CD11c(+) myeloid dendritic cells, and high numbers of FOXP3(+) T cells were each significantly associated with prolonged overall survival, and the latter two parameters were also confirmed by multivariate analysis. For disease-free survival, multivariate analysis revealed significant negative correlations with BCL2 and ARG2 expression by tumor cells. These findings shed new light on mechanisms of cancer progression, and provide rationales for therapeutic inhibition of immunosuppressive mechanisms in head and neck squamous cell carcinoma.
Assuntos
Arginase/biossíntese , Carcinoma de Células Escamosas/imunologia , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Linfócitos T Reguladores/imunologia , Antígeno CD11c/biossíntese , Carcinoma de Células Escamosas/metabolismo , Ciclo-Oxigenase 2/biossíntese , Células Dendríticas/metabolismo , Intervalo Livre de Doença , Fatores de Transcrição Forkhead/biossíntese , Humanos , Lectinas Tipo C/biossíntese , Metástase Linfática , Linfócitos do Interstício Tumoral/metabolismo , Glicoproteínas de Membrana/biossíntese , Células Mieloides/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Receptores Imunológicos/biossíntese , Linfócitos T Reguladores/metabolismoRESUMO
Among synthetic vaccines, virus-like particles (VLPs) are used for their ability to induce strong humoral responses. Very little is reported on VLP-based-vaccine-induced CD4(+) T-cell responses, despite the requirement of helper T cells for antibody isotype switching. Further knowledge on helper T cells is also needed for optimization of CD8(+) T-cell vaccination. Here, we analysed human CD4(+) T-cell responses to vaccination with MelQbG10, which is a Qß-VLP covalently linked to a long peptide derived from the melanoma self-antigen Melan-A. In all analysed patients, we found strong antibody responses of mainly IgG1 and IgG3 isotypes, and concomitant Th1-biased CD4(+) T-cell responses specific for Qß. Although less strong, comparable B- and CD4(+) T-cell responses were also found specific for the Melan-A cargo peptide. Further optimization is required to shift the response more towards the cargo peptide. Nevertheless, the data demonstrate the high potential of VLPs for inducing humoral and cellular immune responses by mounting powerful CD4(+) T-cell help.
Assuntos
Antígeno MART-1/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Vírion/imunologia , Adulto , Idoso , Formação de Anticorpos , Antígenos CD4/metabolismo , Vacinas Anticâncer , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fragmentos de Peptídeos , Linfócitos T Auxiliares-Indutores/patologiaRESUMO
Biodegradable nanoparticles have been employed for vaccine delivery, frequently admixed with adjuvants. Surprisingly, there is little information on their modulation of immune responses, speculated to be negligible. We analyzed the immunomodulatory capacity of alginate-coated chitosan nanogels (Ng), on porcine and human blood dendritic cells (DCs), when applied with defined adjuvants targeting different DC subpopulations. DC maturation, cytokine production and cell migration were assessed. Ng differentially influenced the immunomodulatory characteristics of individual Toll-like receptor (TLR) ligands: Pam3Cys-SK4-induced IL-1ß was enhanced; CpG-oligodeoxynucleotides (CpG-ODN)-induced IFN-α, IL-6 and TNFα were impaired; CpG-ODN-induced CD86 and CCR7, and cell migration, were diminished-plasmacytoid DCs (pDCs) were particularly sensitive. Therein, the Ng influence on DC endocytosis of the TLR ligands was apparently a major contributory element. This demonstrates the importance of predefining the interplay between delivery vehicles and admixed immunostimulatory moieties, for ensuring appropriate immune activation and efficacious combinations. FROM THE CLINICAL EDITOR: Biodegradable nanoparticles have been utilized in vaccine delivery; however, there is little information available on their immunomodulatory properties, which are thought to be negligible. This study clearly demonstrates that nanogels do influence the developing immune response, which needs to be taken into consideration when utilizing these otherwise very efficacious vaccine delivery approaches.
Assuntos
Quitosana/administração & dosagem , Células Dendríticas/citologia , Endocitose/genética , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Receptores Toll-Like/metabolismo , Adjuvantes Imunológicos/administração & dosagem , Alginatos/administração & dosagem , Alginatos/química , Animais , Sangue/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quitosana/química , Células Dendríticas/efeitos dos fármacos , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/química , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/química , Humanos , Ligantes , Nanogéis , Polietilenoglicóis/química , Polietilenoimina/química , SuínosRESUMO
Innate lymphoid cells (ILCs) are plastic immune cells divided into 3 main subsets, characterized by distinct phenotypic and functional profiles. Using single cell approaches, heightened heterogeneity of mouse ILCs has been appreciated, imprinted by tissue signals that shape their transcriptome and epigenome. Intra-subset diversity has also been observed in human ILCs. However, combined transcriptomic and epigenetic analyses of single ILCs in humans are lacking. Here, we show high transcriptional and epigenetic heterogeneity among human circulating ILCs in healthy individuals. We describe phenotypically distinct subclusters and diverse chromatin accessibility within main ILC populations, compatible with differentially poised states. We validate the use of this healthy donor-based analysis as resource dataset to help inferring ILC changes occurring in disease conditions. Overall, our work provides insights in the complex human ILC biology. We anticipate it to facilitate hypothesis-driven studies in patients, without the need to perform single cell OMICs using precious patients' material.
RESUMO
Methods for the analysis of cell secretions at the single-cell level only provide semiquantitative endpoint readouts. Here we describe a microwell array for the real-time spatiotemporal monitoring of extracellular secretions from hundreds of single cells in parallel. The microwell array incorporates a gold substrate with arrays of nanometric holes functionalized with receptors for a specific analyte, and is illuminated with light spectrally overlapping with the device's spectrum of extraordinary optical transmission. Spectral shifts in surface plasmon resonance resulting from analyte-receptor bindings around a secreting cell are recorded by a camera as variations in the intensity of the transmitted light while machine-learning-assisted cell tracking eliminates the influence of cell movements. We used the microwell array to characterize the antibody-secretion profiles of hybridoma cells and of a rare subset of antibody-secreting cells sorted from human donor peripheral blood mononuclear cells. High-throughput measurements of spatiotemporal secretory profiles at the single-cell level will aid the study of the physiological mechanisms governing protein secretion.