RESUMO
Immune checkpoint therapy (ICT) has dramatically altered clinical outcomes for cancer patients and conferred durable clinical benefits, including cure in a subset of patients. Varying response rates across tumor types and the need for predictive biomarkers to optimize patient selection to maximize efficacy and minimize toxicities prompted efforts to unravel immune and non-immune factors regulating the responses to ICT. This review highlights the biology of anti-tumor immunity underlying response and resistance to ICT, discusses efforts to address the current challenges with ICT, and outlines strategies to guide the development of subsequent clinical trials and combinatorial efforts with ICT.
Assuntos
Imunoterapia , Neoplasias , Humanos , Antígeno B7-H1 , Neoplasias/tratamento farmacológico , Ensaios Clínicos como Assunto , Inibidores de Checkpoint Imunológico/administração & dosagemRESUMO
Foxp3+ T regulatory (Treg) cells promote immunological tumor tolerance, but how their immune-suppressive function is regulated in the tumor microenvironment (TME) remains unknown. Here, we used intravital microscopy to characterize the cellular interactions that provide tumor-infiltrating Treg cells with critical activation signals. We found that the polyclonal Treg cell repertoire is pre-enriched to recognize antigens presented by tumor-associated conventional dendritic cells (cDCs). Unstable cDC contacts sufficed to sustain Treg cell function, whereas T helper cells were activated during stable interactions. Contact instability resulted from CTLA-4-dependent downregulation of co-stimulatory B7-family proteins on cDCs, mediated by Treg cells themselves. CTLA-4-blockade triggered CD28-dependent Treg cell hyper-proliferation in the TME, and concomitant Treg cell inactivation was required to achieve tumor rejection. Therefore, Treg cells self-regulate through a CTLA-4- and CD28-dependent feedback loop that adjusts their population size to the amount of local co-stimulation. Its disruption through CTLA-4-blockade may off-set therapeutic benefits in cancer patients.
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Antígeno CTLA-4/metabolismo , Retroalimentação Fisiológica , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antígenos CD28/metabolismo , Proliferação de Células , Células Dendríticas/imunologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Interleucina-2/metabolismo , Ligantes , Linfonodos/metabolismo , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/metabolismo , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Microambiente TumoralRESUMO
Tumors weakly infiltrated by T lymphocytes poorly respond to immunotherapy. We aimed to unveil malignancy-associated programs regulating T cell entrance, arrest, and activation in the tumor environment. Differential expression of cell adhesion and tissue architecture programs, particularly the presence of the membrane tetraspanin claudin (CLDN)18 as a signature gene, demarcated immune-infiltrated from immune-depleted mouse pancreatic tumors. In human pancreatic ductal adenocarcinoma (PDAC) and non-small cell lung cancer, CLDN18 expression positively correlated with more differentiated histology and favorable prognosis. CLDN18 on the cell surface promoted accrual of cytotoxic T lymphocytes (CTLs), facilitating direct CTL contacts with tumor cells by driving the mobilization of the adhesion protein ALCAM to the lipid rafts of the tumor cell membrane through actin. This process favored the formation of robust immunological synapses (ISs) between CTLs and CLDN18-positive cancer cells, resulting in increased T cell activation. Our data reveal an immune role for CLDN18 in orchestrating T cell infiltration and shaping the tumor immune contexture.
Assuntos
Carcinoma Ductal Pancreático , Claudinas , Ativação Linfocitária , Neoplasias Pancreáticas , Linfócitos T Citotóxicos , Animais , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Claudinas/metabolismo , Claudinas/genética , Regulação Neoplásica da Expressão Gênica/imunologia , Sinapses Imunológicas/metabolismo , Sinapses Imunológicas/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Microdomínios da Membrana/metabolismo , Microdomínios da Membrana/imunologia , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral/imunologiaRESUMO
T cell responses upon infection display a remarkably reproducible pattern of expansion, contraction, and memory formation. If the robustness of this pattern builds entirely on signals derived from other cell types or if activated T cells themselves contribute to the orchestration of these population dynamics-akin to bacterial quorum regulation-is unclear. Here, we examined this question using time-lapse microscopy, genetic perturbation, bioinformatic predictions, and mathematical modeling. We found that ICAM-1-mediated cell clustering enabled CD8+ T cells to collectively regulate the balance between proliferation and apoptosis. Mechanistically, T cell expressed CD80 and CD86 interacted with the receptors CD28 and CTLA-4 on neighboring T cells; these interactions fed two nested antagonistic feedback circuits that regulated interleukin 2 production in a manner dependent on T cell density as confirmed by in vivo modulation of this network. Thus, CD8+ T cell-population-intrinsic mechanisms regulate cellular behavior, thereby promoting robustness of population dynamics.
Assuntos
Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/metabolismo , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Comunicação Celular , Contagem de Células , Linhagem Celular , Sobrevivência Celular , Rastreamento de Células , Células Dendríticas/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-2/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos TeóricosRESUMO
Production of interleukin-17 (IL-17) and IL-22 by T helper 17 (Th17) cells and group 3 innate lymphoid cells (ILC3s) in response to the gut microbiota ensures maintenance of intestinal barrier function. Here, we examined the mechanisms whereby the immune system detects microbiota in the steady state. A Syk-kinase-coupled signaling pathway in dendritic cells (DCs) was critical for commensal-dependent production of IL-17 and IL-22 by CD4+ T cells. The Syk-coupled C-type lectin receptor Mincle detected mucosal-resident commensals in the Peyer's patches (PPs), triggered IL-6 and IL-23p19 expression, and thereby regulated function of intestinal Th17- and IL-17-secreting ILCs. Mice deficient in Mincle or with selective depletion of Syk in CD11c+ cells had impaired production of intestinal RegIIIγ and IgA and increased systemic translocation of gut microbiota. Consequently, Mincle deficiency led to liver inflammation and deregulated lipid metabolism. Thus, sensing of commensals by Mincle and Syk signaling in CD11c+ cells reinforces intestinal immune barrier and promotes host-microbiota mutualism, preventing systemic inflammation.
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Células Dendríticas/imunologia , Microbioma Gastrointestinal/imunologia , Interleucina-17/imunologia , Interleucinas/imunologia , Lectinas Tipo C/imunologia , Proteínas de Membrana/imunologia , Quinase Syk/imunologia , Animais , Células Dendríticas/metabolismo , Microbioma Gastrointestinal/fisiologia , Humanos , Interleucina-17/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Nódulos Linfáticos Agregados/microbiologia , Transdução de Sinais/imunologia , Quinase Syk/genética , Quinase Syk/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Interleucina 22RESUMO
Cancer immunotherapies, including checkpoint inhibitors and adoptive cell therapy, manipulate the immune system to recognize and attack cancer cells. These therapies have the potential to induce durable responses in multiple solid and hematologic malignancies and thus have transformed treatment algorithms for numerous tumor types. Cancer immunotherapies lead to unique toxicity profiles distinct from the toxicities of other cancer therapies, depending on their mechanism of action. These toxicities often require specific management, which can include steroids and immune-modulating therapy and for which consensus guidelines have been published. This review will focus on the toxicities of checkpoint inhibitors and chimeric antigen receptor T cells, including pathophysiology, diagnosis, and management.
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Fatores Imunológicos/uso terapêutico , Imunoterapia/métodos , Neoplasias/terapia , HumanosRESUMO
Long-lived parasites evade host immunity through highly evolved molecular strategies. The murine intestinal helminth, Heligmosomoides polygyrus, down-modulates the host immune system through release of an immunosuppressive TGF-ß mimic, TGM1, which is a divergent member of the CCP (Sushi) protein family. TGM1 comprises 5 domains, of which domains 1-3 (D1/2/3) bind mammalian TGF-ß receptors, acting on T cells to induce Foxp3+ regulatory T cells; however, the roles of domains 4 and 5 (D4/5) remain unknown. We noted that truncated TGM1, lacking D4/5, showed reduced potency. Combination of D1/2/3 and D4/5 as separate proteins did not alter potency, suggesting that a physical linkage is required and that these domains do not deliver an independent signal. Coprecipitation from cells treated with biotinylated D4/5, followed by mass spectrometry, identified the cell surface protein CD44 as a coreceptor for TGM1. Both full-length and D4/5 bound strongly to a range of primary cells and cell lines, to a greater degree than D1/2/3 alone, although some cell lines did not respond to TGM1. Ectopic expression of CD44 in nonresponding cells conferred responsiveness, while genetic depletion of CD44 abolished enhancement by D4/5 and ablated the ability of full-length TGM1 to bind to cell surfaces. Moreover, CD44-deficient T cells showed attenuated induction of Foxp3 by full-length TGM1, to levels similar to those induced by D1/2/3. Hence, a parasite protein known to bind two host cytokine receptor subunits has evolved a third receptor specificity, which serves to raise the avidity and cell type-specific potency of TGF-ß signaling in mammalian cells.
Assuntos
Parasitos , Animais , Camundongos , Linfócitos T Reguladores , Transdução de Sinais , Fator de Crescimento Transformador beta , Fatores de Transcrição Forkhead , MamíferosRESUMO
BACKGROUND: Immune checkpoint inhibitors (ICIs), antibodies targeting PD-1 (programmed cell death protein 1)/PD-L1 (programmed death-ligand 1) or CTLA4 (cytotoxic T-lymphocyte-associated protein 4), have revolutionized cancer management but are associated with devastating immune-related adverse events including myocarditis. The main risk factor for ICI myocarditis is the use of combination PD-1 and CTLA4 inhibition. ICI myocarditis is often fulminant and is pathologically characterized by myocardial infiltration of T lymphocytes and macrophages. Although much has been learned about the role of T-cells in ICI myocarditis, little is understood about the identity, transcriptional diversity, and functions of infiltrating macrophages. METHODS: We used an established murine ICI myocarditis model (Ctla4+/-Pdcd1-/- mice) to explore the cardiac immune landscape using single-cell RNA-sequencing, immunostaining, flow cytometry, in situ RNA hybridization, molecular imaging, and antibody neutralization studies. RESULTS: We observed marked increases in CCR2 (C-C chemokine receptor type 2)+ monocyte-derived macrophages and CD8+ T-cells in this model. The macrophage compartment was heterogeneous and displayed marked enrichment in an inflammatory CCR2+ subpopulation highly expressing Cxcl9 (chemokine [C-X-C motif] ligand 9), Cxcl10 (chemokine [C-X-C motif] ligand 10), Gbp2b (interferon-induced guanylate-binding protein 2b), and Fcgr4 (Fc receptor, IgG, low affinity IV) that originated from CCR2+ monocytes. It is important that a similar macrophage population expressing CXCL9, CXCL10, and CD16α (human homologue of mouse FcgR4) was expanded in patients with ICI myocarditis. In silico prediction of cell-cell communication suggested interactions between T-cells and Cxcl9+Cxcl10+ macrophages via IFN-γ (interferon gamma) and CXCR3 (CXC chemokine receptor 3) signaling pathways. Depleting CD8+ T-cells or macrophages and blockade of IFN-γ signaling blunted the expansion of Cxcl9+Cxcl10+ macrophages in the heart and attenuated myocarditis, suggesting that this interaction was necessary for disease pathogenesis. CONCLUSIONS: These data demonstrate that ICI myocarditis is associated with the expansion of a specific population of IFN-γ-induced inflammatory macrophages and suggest the possibility that IFN-γ blockade may be considered as a treatment option for this devastating condition.
Assuntos
Inibidores de Checkpoint Imunológico , Miocardite , Humanos , Camundongos , Animais , Inibidores de Checkpoint Imunológico/efeitos adversos , Linfócitos T CD8-Positivos , Miocardite/induzido quimicamente , Miocardite/metabolismo , Receptor de Morte Celular Programada 1 , Antígeno CTLA-4 , Ligantes , Quimiocinas/metabolismo , Macrófagos/metabolismo , RNA/metabolismoRESUMO
In the last decade, there has been a surge in developing immunotherapies to enhance the immune system's ability to eliminate tumor cells. Bispecific antibodies known as T cell engagers (TCEs) present an attractive strategy in this pursuit. TCEs aim to guide cytotoxic T cells toward tumor cells, thereby inducing a strong activation and subsequent tumor cell lysis. In this study, we investigated the activity of different TCEs on both conventional alpha-beta (αß) T cells and unconventional gamma delta (γδ) T cells. TCEs were built using camelid single-domain antibodies (VHHs) targeting the tumor-associated antigen CEACAM5 (CEA), together with T cell receptor chains or a CD3 domain. We show that Vγ9Vδ2 T cells display stronger in vitro antitumor activity than αß T cells when stimulated with a CD3xCEA TCE. Furthermore, restricting the activation of fresh human peripheral T cells to Vγ9Vδ2 T cells limited the production of protumor factors and proinflammatory cytokines, commonly associated with toxicity in patients. Taken together, our findings provide further insights that γδ T cell-specific TCEs hold promise as specific, effective, and potentially safe molecules to improve antitumor immunotherapies.
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Anticorpos Biespecíficos , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T gama-delta , Humanos , Animais , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Anticorpos Biespecíficos/imunologia , Ativação Linfocitária/imunologia , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Anticorpos de Domínio Único/imunologia , Linhagem Celular Tumoral , Linfócitos T Citotóxicos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Antígeno Carcinoembrionário/imunologiaRESUMO
Determining the appropriate source of antigens for optimal antigen presentation to T cells is a major challenge in designing dendritic cell (DC) -based therapeutic strategies against hepatocellular carcinoma (HCC). Tumor-derived exosomes (Tex) express a wide range of tumor antigens, making them a promising source of antigens for DC vaccines. As reported, the exosomes secreted by tumor cells can inhibit the antitumor function of immune cells. In this study, we transfected hepatocellular carcinoma cells with Rab27a to enhance the yield of exosomes, which were characterized using transmission electron microscopy and Western blot analysis. We found that Tex secreted by overexpressing Rab27a Hepatocellular carcinoma cell lines pulsed DC is beneficial for the differentiation and maturation of DCs but inhibits the secretion of the IL-12 cytokine. Consequently, we developed a complementary immunotherapy approach by using Tex as an antigen loaded onto DCs, in combination with the cytokine IL-12 to induce antigen-specific cytotoxic T lymphocytes ï¼CTLsï¼. The results indicated that the combination of DC-Tex and IL-12 was more effective in stimulating T lymphocyte proliferation, releasing IFN-Î³ï¼ and enhancing cytotoxicity compared to using exosomes or IL-12 alone. Additionally, the inclusion of IL-12 also compensated for the reduced IL-2 secretion by DCs caused by Tex. Moreover, in a BALB/c nude mice model of hepatocellular carcinoma, CTLs induced by DC-Tex combined with IL-12 maximized the tumor-specific T-cell immune effect and suppressed tumor growth. Thus, Tex provides a novel and promising source of antigens, with cytokines compensating for the shortcomings of Tex as a tumor antigen. This work helps to clarify the role of exosomes in tumor immunotherapy and may offer a safe and effective prospective strategy for the clinical application of exosome-based cellular immunotherapy.
Assuntos
Carcinoma Hepatocelular , Células Dendríticas , Exossomos , Interleucina-12 , Neoplasias Hepáticas , Proteínas rab27 de Ligação ao GTP , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Exossomos/metabolismo , Animais , Interleucina-12/metabolismo , Interleucina-12/genética , Proteínas rab27 de Ligação ao GTP/metabolismo , Proteínas rab27 de Ligação ao GTP/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Camundongos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Camundongos Endogâmicos BALB C , Imunoterapia/métodosRESUMO
BACKGROUND: Live attenuated vaccines alter immune functions and are associated with beneficial outcomes. We previously demonstrated that live attenuated yellow fever virus (YFV) vaccine (LA-YF-Vax) dampens T-cell receptor (TCR) signaling in vitro via an RNA-based mechanism. We examined study participants before and after LA-YF-Vax to assess TCR-mediated functions in vivo. METHODS: Serum samples and peripheral blood mononuclear cells (PBMCs) were obtained before and after LA-YF-Vax (with or without additional vaccines) or quadrivalent influenza vaccine. TCR-mediated activation was determined by interleukin 2 release or phosphorylation of the lymphocyte-specific Src kinase. TCR-regulating phosphatase (protein tyrosine phosphatase receptor type E [PTPRE]) expression was also measured. RESULTS: Compared with prevaccination findings, LA-YF-Vax recipient PBMCs demonstrated transient reduction in interleukin 2 release after TCR stimulation and PTPRE levels, unlike in control participants who received quadrivalent influenza vaccine. YFV was detected in 8 of 14 participants after LA-YF-Vax. After incubation of healthy donor PBMCs in serum-derived extracellular vesicles prepared from LA-YF-Vax recipients, TCR signaling and PTPRE levels were reduced after vaccination, even in participants without detectable YFV RNA. CONCLUSIONS: LA-YF-Vax reduces TCR functions and PTPRE levels after vaccination. Extracellular vesicles from serum recapitulated this effect in healthy cells. This likely contributes to the reduced immunogenicity for heterologous vaccines after LA-YF-Vax administration. Identification of specific immune mechanisms related to vaccines should contribute to understanding of the "off-target," beneficial effects of live vaccines.
Assuntos
Vacinas contra Influenza , Vacina contra Febre Amarela , Humanos , Interleucina-2 , Leucócitos Mononucleares , Anticorpos Antivirais , Vírus da Febre Amarela , Antígenos Virais , Vacinas Combinadas , Receptores de Antígenos de Linfócitos T , RNA , Vacinas AtenuadasRESUMO
Expansion of CD4+CD28null T-lymphocytes is common in chronic heart failure (CHF) patients. Its ability to produce high levels of proinflammatory cytokines is probably the key role of these cells in CHF. IL-10 is a candidate for limiting CD4+CD28null T-lymphocyte responses, whereas tumour necrosis factor (TNF) is the cytokine most closely involved in the loss of CD28 expression. Serum levels of TNF and IL-10 were measured in 65 CHF patients (mean age, 65.2 ± 13.84 years). Patients with an IL-10/TNF ratio ≥1 had significantly lower levels of CD4+CD28null T-lymphocytes than those with a ratio <1. In vitro, IL-10 reduced the frequency of proliferative CD4+CD28null T-lymphocytes stimulated with anti-CD3. Pre-treatment with IL-10 before anti-CD3 stimulation was required for the cytokine to inhibit TNF production by CD4+CD28null T-lymphocytes. In addition to the previously described effect of IL-10 on HLA-DR and ICAM-1 expression, LFA-3 protein and mRNA levels were reduced in the presence of the cytokine in monocytes. IL-10 inhibition on CD4+CD28null T-lymphocytes may be mediated by a reduction in HLA class II and LFA-3 expression because blocking interactions with these costimulators has similar effects to those of IL-10 treatment. Moreover, costimulation through CD2/LFA-3 interaction is enough to induce proliferation and cytokine production in CD4+CD28null T-lymphocytes.
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Cutaneous neurofibromas (cNFs) are characteristic of neurofibromatosis 1 (NF1), yet their immune microenvironment is incompletely known. A total of 61 cNFs from 10 patients with NF1 were immunolabeled for different types of T cells and macrophages, and the cell densities were correlated with clinical characteristics. Eight cNFs and their overlying skin were analyzed for T cell receptor CDR domain sequences, and mass spectrometry of 15 cNFs and the overlying skin was performed to study immune-related processes. Intratumoral T cells were detected in all cNFs. Tumors from individuals younger than the median age of the study participants (33 years), growing tumors, and tumors smaller than the data set median showed increased T cell density. Most samples displayed intratumoral or peritumoral aggregations of CD3-positive cells. T cell receptor sequencing demonstrated that the skin and cNFs host distinct T cell populations, whereas no dominant cNF-specific T cell clones were detected. Unique T cell clones were fewer in cNFs than in skin, and mass spectrometry suggested lower expression of proteins related to T cell-mediated immunity in cNFs than in skin. CD163-positive cells, suggestive of M2 macrophages, were abundant in cNFs. Human cNFs have substantial T cell and macrophage populations that may be tumor-specific.
Assuntos
Neurofibroma , Neurofibromatose 1 , Neoplasias Cutâneas , Humanos , Adulto , Neurofibromatose 1/patologia , Neurofibroma/metabolismo , Neurofibroma/patologia , Neoplasias Cutâneas/metabolismo , Receptores de Antígenos de Linfócitos T , Microambiente TumoralRESUMO
Autoimmune encephalitis (AE) is an inflammatory disease of the central nervous system characterized by the production of various autoimmune antibodies targeting neuronal proteins. The pathogenesis of AE remains elusive. Accumulating evidence suggests that lymphocytes, particularly B and T lymphocytes, play an integral role in the development of AE. In the last two decades, autoimmune neural antibodies have taken center stage in diagnosing AE. Recently, increasing evidence has highlighted the importance of T lymphocytes in the onset of AE. CD4+ T cells are thought to influence disease progression by secreting associated cytokines, whereas CD8+ T cells exert a cytotoxic role, causing irreversible damage to neurons mainly in patients with paraneoplastic AE. Conventionally, the first-line treatments for AE include intravenous steroids, intravenous immunoglobulin, and plasma exchange to remove pathogenic autoantibodies. However, a minority of patients are insensitive to conventional first-line treatment protocols and suffer from disease relapse, a condition referred to as refractory AE. In recent years, new treatments, such as rituximab or CAAR-T, which target pathogenic lymphocytes in patients with AE, have offered new therapeutic options for refractory AE. This review aims to describe the current knowledge about the function of B and T lymphocytes in the pathophysiology of AE and to summarize and update the immunotherapy options for treating this disease.
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Chronic lymphocytic leukemia (CLL) is characterized by dysfunctional B cells. Immune checkpoint molecules such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death-1 (PD-1) are upregulated in patients with CLL and may correlate with prognostic markers such as beta-2 microglobulin (B2M). The aim of this study was to evaluate the levels of immune checkpoints on B cell subsets and to further correlate them with B2M levels in patients with CLL. We recruited 21 patients with CLL and 12 controls. B cell subsets and the levels of immune checkpoint expression were determined using conventional multi-color flow cytometry. Basal levels of B2M in patients with CLL were measured using an enzyme-linked immunosorbent assay. Patients with CLL had increased levels of activated B cells when compared to the control group, p < 0.001. The expression of PD-1 and CTLA-4 were increased on activated B cells and memory B cells, p < 0.05. There were no associations between B2M levels and the measured immune checkpoints on B cell subsets, after adjusting for sex and age. In our cohort, the patients with CLL expressed elevated levels of PD-1 and CTLA-4 immune checkpoints on activated and memory B cell subsets. However, there was no correlation between these immune checkpoint expressions and B2M levels.
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BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by disturbance of pro-inflammatory and anti-inflammatory lymphocytes. Growing evidence shown that gut microbiota participated in the occurrence and development of SLE by affecting the differentiation and function of intestinal immune cells. The purpose of this study was to investigate the changes of gut microbiota in SLE and judge its associations with peripheral T lymphocytes. METHODS: A total of 19 SLE patients and 16 HCs were enrolled in this study. Flow cytometry was used to detect the number of peripheral T lymphocyte subsets, and 16 s rRNA was used to detect the relative abundance of gut microbiota. Analyzed the correlation between gut microbiota with SLEDAI, ESR, ds-DNA and complement. SPSS26.0 software was used to analyze the experimental data. Mann-Whitney U test was applied to compare T lymphocyte subsets. Spearman analysis was used for calculating correlation. RESULTS: Compared with HCs, the proportions of Tregs (P = 0.001), Tfh cells (P = 0.018) and Naïve CD4 + T cells (P = 0.004) significantly decreased in SLE patients, and proportions of Th17 cells (P = 0.020) and γδT cells (P = 0.018) increased in SLE. The diversity of SLE patients were significantly decreased. Addition, there were 11 species of flora were discovered to be distinctly different in SLE group (P < 0.05). In the correlation analysis of SLE, Tregs were positively correlated with Ruminococcus2 (P = 0.042), Th17 cells were positively correlated with Megamonas (P = 0.009), γδT cells were positively correlated with Megamonas (P = 0.003) and Streptococcus (P = 0.004), Tfh cells were positively correlated with Bacteroides (P = 0.040), and Th1 cells were negatively correlated with Bifidobacterium (P = 0.005). As for clinical indicators, the level of Tregs was negatively correlated with ESR (P = 0.031), but not with C3 and C4, and the remaining cells were not significantly correlated with ESR, C3 and C4. CONCLUSION: Gut microbiota and T lymphocyte subsets of SLE changed and related to each other, which may break the immune balance and affect the occurrence and development of SLE. Therefore, it is necessary to pay attention to the changes of gut microbiota and provide new ideas for the treatment of SLE.
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Microbioma Gastrointestinal , Lúpus Eritematoso Sistêmico , Subpopulações de Linfócitos T , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/microbiologia , Microbioma Gastrointestinal/imunologia , Feminino , Adulto , Masculino , Subpopulações de Linfócitos T/imunologia , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Adulto Jovem , Células Th17/imunologiaRESUMO
Acute T-lymphocyte leukemia (T-ALL) is a malignant tumor disease. RNA-binding protein neotumor ventral antigen-1 (NOVA1) is highly expressed in bone marrow mononuclear cells of T-ALL patients, while the role of NOVA1 in T-ALL progression remains unknown. The gain- and loss-of-function studies for NOVA1 were performed in Jurkat and CCRF-CEM cells. NOVA1 overexpression promoted cell proliferation and cell cycle progression. NOVA1 knockdown increased the apoptosis rate of T-ALL cells. Ubiquitin-specific protease 44 (USP44), a nuclear protein with deubiquitinase catalytic activity, has been reported to play an oncogene role in human T-cell leukemia. USP44 expression was positively associated with NOVA1, and RNA immunoprecipitation assay verified the binding of NOVA1 to the mRNA of USP44. USP44 knockdown partially abolished NOVA1-induced cell proliferation and inhibition of apoptosis. The in vivo xenograft experiment was performed by injection of T-ALL tumor cells into the tail vein of NOD/SCID mice. The knockdown of NOVA1 had lower tumorigenicity. NOVA1 knockdown alleviated pathological changes in lung and spleen tissues, and increased the overall survival period and the weight of T-ALL mice. Thus, NOVA1 acts as an accelerator in T-ALL, and its function might be achieved by binding to and stabilizing USP44 mRNA.
Assuntos
Antígeno Neuro-Oncológico Ventral , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Camundongos , Animais , RNA Mensageiro/genética , Linhagem Celular Tumoral , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Linfócitos T/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismoRESUMO
The therapeutic efficacy of radiotherapy (RT) is primarily driven by two factors: biophysical DNA damage in cancer cells and radiation-induced anti-tumor immunity. However, Anti-tumor immune responses between X-ray RT (XRT) and carbon-ion RT (CIRT) remain unclear. In this study, we, employed mouse models to assess the immunological contribution, especially cytotoxic T-lymphocyte (CTL)-mediated immunity, to the therapeutic effectiveness of XRT and CIRT in shrinking tumors. We irradiated mouse intradermal tumors of B16F10-ovalbumin (OVA) mouse melanoma cells and 3LL-OVA mouse lung cancer cells with carbon-ion beams or X-rays in the presence or absence of CTLs. CTL removal was performed by administration of anti-CD8 monoclonal antibody (mAb) in mice. Based on tumor growth delay, we determined the tumor growth and regression curves. The enhancement ratio (ER) of the slope of regression lines in the presence of CTLs, relative to the absence of CTLs, indicates the dependency of RT on CTLs for shrinking mouse tumors, and the biological effectiveness (RBE) of CIRT relative to XRT were calculated. Tumor growth curves revealed that the elimination of CD8+ CTLs by administrating anti-CD8 mAb accelerated tumor growth compared to the presence of CTLs in both RTs. The ERs were larger in CIRT compared to XRT in the B16F10-OVA tumor models, but not in the 3LL-OVA models, suggesting a greater contribution of CTL-mediated anti-tumor immunity to tumor reduction in CIRT compared to XRT in the B16F10-OVA tumor model. In addition, the RBE values for both models were larger in the presence of CTLs compared to models without CTLs, suggesting that CIRT may utilize CTL-mediated anti-tumor immunity more than X-ray. The findings from this study suggest that although immunological contribution to therapeutic efficacy may vary depending on the type of tumor cell, CIRT utilizes CTL-mediated immunity to a greater extent compared to XRT.
Assuntos
Camundongos Endogâmicos C57BL , Linfócitos T Citotóxicos , Animais , Linfócitos T Citotóxicos/imunologia , Camundongos , Linhagem Celular Tumoral , Melanoma Experimental/imunologia , Melanoma Experimental/radioterapia , Melanoma Experimental/terapia , Melanoma Experimental/patologia , Radioterapia com Íons Pesados/métodos , Terapia por Raios X , Feminino , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologiaRESUMO
Miniaturized flow cytometry has significant potential for portable applications, such as cell-based diagnostics and the monitoring of therapeutic cell manufacturing, however, the performance of current techniques is often limited by the inability to resolve spectrally-overlapping fluorescence labels. Here, the study presents a computational hyperspectral microflow cytometer (CHC) that enables accurate discrimination of spectrally-overlapping fluorophores labeling single cells. CHC employs a dispersive optical element and an optimization algorithm to detect the full fluorescence emission spectrum from flowing cells, with a high spectral resolution of ≈3 nm in the range from 450 to 650 nm. CHC also includes a dedicated microfluidic device that ensures in-focus imaging through viscoelastic sheathless focusing, thereby enhancing the accuracy and reliability of microflow cytometry analysis. The potential of CHC for analyzing T lymphocyte subpopulations and monitoring changes in cell composition during T cell expansion is demonstrated. Overall, CHC represents a major breakthrough in microflow cytometry and can facilitate its use for immune cell monitoring.
Assuntos
Citometria de Fluxo , Citometria de Fluxo/métodos , Humanos , Linfócitos T/citologia , AlgoritmosRESUMO
Elucidating the mechanisms underlying the persistence and location of the HIV reservoir is critical for developing cure interventions. While it has been shown that levels of T-cell activation and the size of the HIV reservoir are greater in rectal tissue and lymph nodes (LN) than in blood, the relative contributions of T-cell subsets to this anatomic difference are unknown. We measured and compared HIV-1 DNA content, expression of the T-cell activation markers CD38 and HLA-DR, and expression of the exhaustion markers programmed cell death protein 1 (PD-1) and T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) in naive, central memory (CM), transitional memory (TM), and effector memory (EM) CD4+ and CD8+ T-cells in paired blood and LN samples among 14 people with HIV who were receiving antiretroviral therapy. HIV-1 DNA levels, T-cell immune activation, and TIGIT expression were higher in LN than in blood, especially in CM and TM CD4+ T-cell subsets. Immune activation was significantly higher in all CD8+ T-cell subsets, and memory CD8+ T-cell subsets from LN had higher levels of PD-1 expression, compared with blood, while TIGIT expression levels were significantly lower in TM CD8+ T-cells. The differences seen in CM and TM CD4+ T-cell subsets were more pronounced among participants with CD4+ T-cell counts of <500 cells/µL within 2 years after antiretroviral therapy initiation, thus highlighting increased residual dysregulation in LN as a distinguishing feature of and a potential mechanism for individuals with suboptimal CD4+ T-cell recovery during antiretroviral therapy. IMPORTANCE This study provides new insights into the contributions of different CD4+ and CD8+ T-cell subsets to the anatomic differences between LN and blood in individuals with HIV who have optimal versus suboptimal CD4+ T-cell recovery. To our knowledge, this is the first study comparing paired LN and blood CD4+ and CD8+ T-cell differentiation subsets, as well as those subsets in immunological responders versus immunological suboptimal responders.