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1.
J Nutr ; 154(10): 3133-3143, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39019165

RESUMO

BACKGROUND: Evidence shows that CD4+ T cells are altered in obesity and play a significant role in the systemic inflammation in adults with the disease. OBJECTIVES: Because the profile of these cells is poorly understood in the pediatric population, this study aims to investigate the profile of CD4+ T lymphocytes and the plasma levels of cytokines in this population. METHODS: Using flow cytometry, we compared the expression profile of lymphocyte markers, master transcription factors, cytokines, and molecules involved in the regulation of the immune response in CD4+ T cells from children and adolescents with obesity (OB group, n = 20) with those with eutrophy group (EU group, n = 16). Plasma levels of cytokines in both groups were determined by cytometric bead array (CBA). RESULTS: The OB group presents a lower frequency of CD3+ T cells, as well as a decreased frequency of CD4+ T cells expressing CD28, IL-4, and FOXP3, but an increased frequency of CD4+IL-17A+ cells compared with the EU group. The frequency of CD28 is increased in Th2 and Treg cells in the OB group, whereas CTLA-4 is decreased in all subpopulations compared with the EU group. Furthermore, Th2, Th17, and Treg profiles can differentiate the EU and OB groups. IL-10 plasma levels are reduced in the OB group and negatively correlated with adiposity and inflammatory parameters. CONCLUSIONS: CD4+ T cells have an altered pattern of expression in children and adolescents with obesity, contributing to the inflammatory state and clinical characteristics of these patients.


Assuntos
Linfócitos T CD4-Positivos , Citocinas , Humanos , Criança , Adolescente , Feminino , Masculino , Linfócitos T CD4-Positivos/imunologia , Citocinas/sangue , Citocinas/metabolismo , Obesidade/imunologia , Subpopulações de Linfócitos T/imunologia , Obesidade Infantil/imunologia , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Antígeno CTLA-4/metabolismo , Interleucina-4/sangue , Antígenos CD28/metabolismo
2.
Front Immunol ; 15: 1347318, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500881

RESUMO

Immune checkpoint pathways, i.e., coinhibitory pathways expressed as feedback following immune activation, are crucial for controlling an excessive immune response. Cytotoxic T lymphocyte antigen-4 (CTLA-4) and programmed cell death protein-1 (PD-1) are the central classical checkpoint inhibitory (CPI) molecules used for the control of neoplasms and some infectious diseases, including some fungal infections. As the immunosuppression of severe paracoccidioidomycosis (PCM), a chronic granulomatous fungal disease, was shown to be associated with the expression of coinhibitory molecules, we hypothesized that the inhibition of CTLA-4 and PD-1 could have a beneficial effect on pulmonary PCM. To this end, C57BL/6 mice were infected with Paracoccidioides brasiliensis yeasts and treated with monoclonal antibodies (mAbs) α-CTLA-4, α-PD-1, control IgG, or PBS. We verified that blockade of CTLA-4 and PD-1 reduced the fungal load in the lungs and fungal dissemination to the liver and spleen and decreased the size of pulmonary lesions, resulting in increased survival of mice. Compared with PBS-treated infected mice, significantly increased levels of many pro- and anti-inflammatory cytokines were observed in the lungs of α-CTLA-4-treated mice, but a drastic reduction in the liver was observed following PD-1 blockade. In the lungs of α-CPI and IgG-treated mice, there were no changes in the frequency of inflammatory leukocytes, but a significant reduction in the total number of these cells was observed. Compared with PBS-treated controls, α-CPI- and IgG-treated mice exhibited reduced pulmonary infiltration of several myeloid cell subpopulations and decreased expression of costimulatory molecules. In addition, a decreased number of CD4+ and CD8+ T cells but sustained numbers of Th1, Th2, and Th17 T cells were detected. An expressive reduction in several Treg subpopulations and their maturation and suppressive molecules, in addition to reduced numbers of Treg, TCD4+, and TCD8+ cells expressing costimulatory and coinhibitory molecules of immunity, were also detected. The novel cellular and humoral profiles established in the lungs of α-CTLA-4 and α-PD-1-treated mice but not in control IgG-treated mice were more efficient at controlling fungal growth and dissemination without causing increased tissue pathology due to excessive inflammation. This is the first study demonstrating the efficacy of CPI blockade in the treatment of pulmonary PCM, and further studies combining the use of immunotherapy with antifungal drugs are encouraged.


Assuntos
Paracoccidioidomicose , Camundongos , Animais , Antígeno CTLA-4 , Receptor de Morte Celular Programada 1 , Camundongos Endogâmicos C57BL , Gravidade do Paciente , Imunoglobulina G
3.
Clin Exp Immunol ; 217(1): 78-88, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38517030

RESUMO

Although perianal Crohn's disease (PCD) is highly associated with the exacerbated inflammation, the molecular basis and immunological signature that distinguish patients who present a history of perianal lesions are still unclear. This paper aims to define immunological characteristics related to PCD. In this cross-sectional observational study, we enrolled 20 healthy controls and 39 CD patients. Blood samples were obtained for the detection of plasma cytokines and lipopolysaccharides (LPS). Peripheral blood mononuclear cells (PBMCs) were phenotyped by flow cytometry. Leukocytes were stimulated with LPS or anti-CD3/anti-CD28 antibodies. Our results show that CD patients had augmented plasma interleukin (IL)-6 and LPS. However, their PBMC was characterized by decreased IL-6 production, while patients with a history of PCD produced higher IL-6, IL-8, and interferon-γ, along with decreased tumor necrosis factor alpha (TNF). CD patients had augmented FoxP3 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) regulatory markers, though the PCD subjects presented a significant reduction in CTLA-4 expression. CTLA-4 as well as IL-6 and TNF responses were able to distinguish the PCD patients from those who did not present perianal complications. In conclusion, IL-6, TNF, and CTLA-4 exhibit a distinct expression pattern in CD patients with a history of PCD, regardless of disease activity. These findings clarify some mechanisms involved in the development of the perianal manifestations and may have a great impact on the disease management.


Assuntos
Antígeno CTLA-4 , Doença de Crohn , Humanos , Antígeno CTLA-4/metabolismo , Doença de Crohn/imunologia , Doença de Crohn/sangue , Masculino , Feminino , Adulto , Estudos Transversais , Pessoa de Meia-Idade , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Interleucina-6/sangue , Lipopolissacarídeos/imunologia , Citocinas/sangue , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Transcrição Forkhead/metabolismo
4.
Cell Rep Med ; 4(12): 101256, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38118422

RESUMO

FLT3-L-dependent classical dendritic cells (cDCs) recruit anti-tumor and tumor-protecting lymphocytes. We evaluate cancer growth in mice with low, normal, or high levels of cDCs. Paradoxically, both low or high numbers of cDCs improve survival in mice with melanoma. In low cDC context, tumors are restrained by the adaptive immune system through influx of effector T cells and depletion of Tregs and NK cells. High cDC numbers favor the innate anti-tumor response, with massive recruitment of activated NK cells, despite high Treg infiltration. Anti CTLA-4 but not anti PD-1 therapy synergizes with FLT3-L therapy in the cDCHi but not in the cDCLo context. A combination of cDC boost and Treg depletion dramatically improves survival of tumor-bearing mice. Transcriptomic data confirm the paradoxical effect of cDC levels on survival in several human tumor types. cDCHi-TregLo state in such patients predicts best survival. Modulating cDC numbers via FLT3 signaling may have therapeutic potential in human cancer.


Assuntos
Neoplasias , Linfócitos T Reguladores , Humanos , Camundongos , Animais , Células Matadoras Naturais , Células Dendríticas , Homeostase
5.
Cancers (Basel) ; 15(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37760516

RESUMO

The introduction of immunotherapy has brought about a paradigm shift in the management of advanced non-small cell lung cancer (NSCLC). It has not only significantly improved the prognosis of patients but has also become a cornerstone of treatment, particularly in those without oncogenic driver mutations. Immune checkpoint inhibitors (ICIs) play a crucial role in the treatment of lung cancer and can be classified into two main groups: Anti-cytotoxic T lymphocyte antigen-4 (Anti-CTLA-4) and anti-T-cell receptor programmed cell death-1 or its ligand (Anti-PD-1 and Anti-PD-L1). Certainly, the landscape of approved first line immunotherapeutic approaches has expanded to encompass monotherapy, immunotherapy-exclusive protocols, and combinations with chemotherapy. The complexity of decision-making in this realm arises due to the absence of direct prospective comparisons. However, a thorough analysis of the long-term efficacy and safety data derived from pivotal clinical trials can offer valuable insights into optimizing treatment for different patient subsets. Moreover, ongoing research is investigating emerging biomarkers and innovative therapeutic strategies that could potentially refine the current treatment approach even further. In this comprehensive review, our aim is to highlight the latest advances in immunotherapy for advanced NSCLC, including the mechanisms of action, efficacy, safety profiles, and clinical significance of ICI.

6.
Front Med (Lausanne) ; 10: 1160368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601778

RESUMO

Background: Colorectal cancer (CRC) is a prevalent cancer, ranking as the third most common. Recent advances in our understanding of the molecular causes of this disease have highlighted the crucial role of tumor immune evasion in its initiation and progression. CTLA4, a receptor that acts as a negative regulator of T cell responses, plays a pivotal role in this process, and genetic variations in CTLA4 have been linked to CRC susceptibility, prognosis, and response to therapy. Methods: We conducted a case-control study involving 98 CRC patients and 424 controls. We genotyped the CTLA4 c.-319C > T variant (rs5742909) and performed an association analysis by comparing allele frequencies between the patients and controls. To assess the potential functional impact of this variant, we first performed an In Silico analysis of transcription factor binding sites using Genomatix. Finally, to validate our findings, we conducted a luciferase reporter gene assay using different cell lines and an electrophoretic mobility shift assay (EMSA). Results: The case-control association analysis revealed a significant association between CTLA4 c.-319C > T and CRC susceptibility (p = 0.023; OR 1.89; 95% CI = 1.11-3.23). Genomatix analysis identified LEF1 and TCF7 transcription factors as specific binders to CTLA4 c.-319C. The reporter gene assay demonstrated notable differences in luciferase activity between the c.-319 C and T alleles in COS-7, HCT116, and Jurkat cell lines. EMSA analysis showed differences in TCF7 interaction with the CTLA4 C and T alleles. Conclusion: CTLA4 c.-319C > T is associated with CRC susceptibility. Based on our functional validation results, we proposed that CTLA4 c.-319C > T alters gene expression at the transcriptional level, triggering a stronger negative regulation of T-cells and immune tumoral evasion.

7.
Inflammation ; 46(5): 1639-1652, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37237069

RESUMO

Recent evidence has pointed out that the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) expression is a poor prognosis factor. However, the implications of CTLA-4 expression on circulating inflammatory mediators are unclear for breast cancer. Tumor biopsies and blood samples were collected from 117 breast cancer patients. Oxidative stress parameters were evaluated in plasma samples by measuring the lipoperoxidation profile and nitric oxide metabolites (NOx). Interleukins 12 (IL-12) and 4 (IL-4) were assessed by ELISA. CTLA-4 expression was determined by immunofluorescence assessed by its labeling in tumor-infiltrating leukocytes (TILs) or breast tumors. Correlations between CTLA-4 expression in breast tumors with TCD4/TCD8 infiltrating lymphocyte and inflammation-related genes were performed using data from TIMER 2.0/TCGA databases (n = 2160). CTLA-4 expression in TILs significantly correlated to triple-negative breast tumors. Patients carrying CTLA-4-positive tumors exhibited lower plasmatic NOx levels, and those expressing CTLA-4 in TILs had reduced levels of IL-12 in plasma. No changes in either IL-4 or lipid peroxidation profiles were detected concerning any CTLA4 status. Compared to the Luminal A ones, oxidative stress parameters and cytokines were observed in patients bearing triple-negative tumors. CTLA-4 expression in all breast cancer subtypes positively correlated to TCD4/TCD8 lymphocyte infiltrates, as well as to the pro-inflammatory genes IL12A, IL4, NFKB1, NFKB2, NOS1, NOS2, and NOS3. CTLA-4 expression in both tumor and TILs can affect the systemic inflammatory status of breast cancer patients, especially antitumor molecules such as IL-12 and NOx that correlate to more aggressive disease.


Assuntos
Linfócitos do Interstício Tumoral , Neoplasias de Mama Triplo Negativas , Humanos , Antígeno CTLA-4/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Interleucina-4/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Interleucina-12/metabolismo , Prognóstico
8.
Eur J Immunol ; 53(8): e2350372, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37160134

RESUMO

Regulatory and effector cell responses to Plasmodium vivax, the most common human malaria parasite outside Africa, remain understudied in naturally infected populations. Here, we describe peripheral CD4+ T- and B-cell populations during and shortly after an uncomplicated P. vivax infection in 38 continuously exposed adult Amazonians. Consistent with previous observations, we found an increased frequency in CD4+ CD45RA- CD25+ FoxP3+ T regulatory cells that express the inhibitory molecule CTLA-4 during the acute infection, with a sustained expansion of CD21- CD27- atypical memory cells within the CD19+ B-cell compartment. Both Th1- and Th2-type subsets of CXCR5+ ICOShi PD-1+ circulating T follicular helper (cTfh) cells, which are thought to contribute to antibody production, were induced during P. vivax infection, with a positive correlation between overall cTfh cell frequency and IgG antibody titers to the P. vivax blood-stage antigen MSP119 . We identified significant changes in cell populations that had not been described in human malaria, such as an increased frequency of CTLA-4+ T follicular regulatory cells that antagonize Tfh cells, and a decreased frequency of circulating CD24hi CD27+ B regulatory cells in response to acute infection. In conclusion, we disclose a complex immunoregulatory network that is critical to understand how naturally acquired immunity develops in P. vivax malaria.


Assuntos
Malária Vivax , Plasmodium vivax , Adulto , Humanos , Plasmodium vivax/fisiologia , Antígeno CTLA-4 , Linfócitos T Auxiliares-Indutores , Linfócitos T CD4-Positivos
9.
Clin Transl Oncol ; 25(11): 3122-3138, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37036597

RESUMO

Although the incidence rate and mortality of gastric/gastroesophageal cancer (G/GEJC) are declining globally, G/GEJC remains a health issue in East Asia. When diagnosed as advanced stage, treatment after serial lines of chemotherapy is limited, with a median overall survival of less than 1 year. Immunotherapy, including immune checkpoint inhibitors (ICIs) and cellular immunotherapy, has changed the prospects of cancer therapy by reversing immune suppression in the tumor microenvironment. As part of this review, we enumerated the clinical uses of ICIs related to the immunosuppressive signaling axis PD-1/PD-L1 and CTLA-4/B7. ICIs were initially approved as a secondary treatment option for patients with severe pretreating advanced gastric and gastroesophageal cancer (AG/GEJC). Till now, it has become the mainstream therapy in combination with chemotherapy and targeted therapy for patients identified by biomarkers. Numerous evidence showed microsatellite instability (MSI), programmed cell death ligand 1 (PD-L1) expression, tumor mutation burden (TMB) and Epstein-Barr virus (EBV) status might be indicative to the use of ICIs. In addition, we discussed the current limitations and prospects of ICIs in AG/GGEJC, as well as the first clinical application of novel CAR-T cell therapies.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Antígeno B7-H1/metabolismo , Herpesvirus Humano 4 , Imunoterapia , Neoplasias Gástricas/tratamento farmacológico , Microambiente Tumoral
10.
Immunol Res ; 71(5): 679-686, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37014514

RESUMO

Cancer is classified into metabolic and/or genetic disorders; notably, the tryptophan catabolism pathway is vital in different cancer types. Here, we focused on the interaction and molecular connection between the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) receptor and indoleamine-2,3-dioxygenase (IDO) enzyme. To test the impact of the selected immunotherapies on breast cancer cell migration and cell survival, we used in vitro assays. Also, we test the impact of anti-CTLA-4 antibody on the IDO-positive cells. The results of cell migration and clonogenic assays showed that anti-CTLA-4 antibody reduces cancer cell migration and clonogenic abilities of murine breast cancer cells. In addition, the result of flow cytometry showed that the anti-CTLA-4 antibody did not change the percentage of IDO-positive cancer cells. Notably, administrating an IDO blocker, 1-Methyl-DL-tryptophan (1MT), reduces the efficiency of the antiCTLA-4 antibody. The enzymatic blocking of the IDO reduces the efficiency of the anti-CTLA-4 antibody on cell migration and clonogenic abilities suggesting that there is an inhibitory interaction at the molecular level between functions of CTLA-4 and IDO. It is unclear via which mechanism(s) IDO interacts with CTLA-4 signaling and also why blocking IDO makes disruption in CTLA-4 signaling in cancer cells. Indeed, evaluating the role of IDO in CTLA-4 signaling in cancer cells may assist in clarifying a poor response to CTLA-4 immunotherapies by some patients. Hence, further investigation of the molecular interaction between CTLA-4 and IDO might help to improve the efficiency of CTLA-4 immunotherapy.


Assuntos
Neoplasias da Mama , Humanos , Animais , Camundongos , Feminino , Triptofano/metabolismo , Antígeno CTLA-4 , Transdução de Sinais , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo
11.
Hum Cell ; 36(4): 1225-1232, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36907978

RESUMO

In the tumor microenvironment, the function of T cells is a fate-changer for tumor progression. In the meantime, CD28 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) are vital role players in the controlling activity of T cells as an activator and deactivator, respectively. In T cells in comparison to CD28, the molecular mechanism of CTLA-4 is unclear. In addition, despite the fact that most tumor cell types express CTLA-4, its role in tumor cells is not well understood and only few studies focused on the role of CTLA-4 signaling in tumor cells. It is illustrated that CTLA-4 signaling causes PD-L1 expression in tumor cells. However, numerous characteristics of CTLA-4 signaling in tumor cells are ambiguous and require to be described. In this article, we proposed that the CTLA-4 signaling during immunotherapy with anti-CTLA-4 antibodies may cause poor responses by patients. In addition, we attract attention to several fundamental questions regarding CTLA-4 signaling in tumor cells. Overall, the CTLA-4 signaling function and the related gaps about its role in tumor cells in the present review are challenged.


Assuntos
Antígenos CD28 , Linfócitos T Citotóxicos , Humanos , Antígenos CD28/metabolismo , Linfócitos T Citotóxicos/metabolismo , Antígeno CTLA-4 , Imunoterapia , Transdução de Sinais/genética
12.
Immunotherapy ; 15(5): 343-351, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36852429

RESUMO

Background: Predicting the roughly 50% of melanoma patients that will respond to immunotherapy is challenging. We tested if splenic volume could be a predictive biomarker. Methods: Splenic volume was measured by a semiautomated commercial software tool in pre- and post-treatment PET/CT, CT or MRI in 50 melanoma patients treated with immune checkpoint inhibitors. Results: Subjects with smaller spleens had better progression-free survival (median not achieved after 30.6 months of follow-up vs median 11.2 months; p = 0.0213) than their counterparts. A cut-off of <244 cm3 yielded a sensitivity of 83% and specificity of 54% to identify responders. Conclusion: Measuring splenic volume on imaging scans is feasible. Smaller pretreatment spleen volume is associated with better responses to immune checkpoint inhibitors.


For patients with relapsed or advanced melanoma, immunotherapy is the main treatment option. Not all patients respond to it and there are few ways of knowing the odds beforehand. Treatment can be costly and dangerous. We investigated if measuring the spleen using imaging scans already routinely done to monitor the disease could give doctors an idea of whether the patient had higher chances of responding to immunotherapy. Our main finding was that patients with smaller spleens before treatment initiation were more likely to respond to immunotherapy and live longer without the disease. This finding can potentially be used in day-to-day care to inform patients and their physicians of the patient's odds and help them make an informed joint decision.


Assuntos
Melanoma , Baço , Humanos , Baço/diagnóstico por imagem , Inibidores de Checkpoint Imunológico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Melanoma/diagnóstico por imagem , Melanoma/terapia , Imunoterapia
13.
Curr Oncol ; 30(1): 1267-1274, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36661747

RESUMO

Since the 2018 Nobel prize in medicine was granted to the discovery of immune escape by cancer cells, billions of dollars have been spent on a new form of cancer immunotherapy called immune checkpoint inhibition (ICI). In this treatment modality, monoclonal antibodies (mAbs) are used to block cell-surface glycoproteins responsible for cancer immune escape. However, only a subset of patients benefit from this treatment. In this commentary, we focus on the polymorphism in the target molecules of these mAbs, namely PD-1, PD-L1 and CTLA4; we explain that using a single mAb from one clone is unlikely to succeed in treating all humans because humans have a genotype and phenotype polymorphism in these molecules. Monoclonal antibodies are highly specific and are capable of recognizing only one epitope ("monospecific"), which makes them ideal for use in laboratory animals because these animals are generationally inbred and genetically identical (isogenic). In humans, however, the encoding genes for PD-1, PD-L1 and CTLA4 have variations (alleles), and the final protein products have phenotype polymorphism. This means that small differences exist in these proteins among individual humans, rendering one mAb too specific to cover all patients. Our suggestion for the next step in advancing this oncotherapy is to focus on methods to tailor the mAb treatment individually for each patient or replace a single clone of mAb with less specific alternatives, e.g., a "cocktail of mAbs", oligoclonal antibodies or recombinant polyclonal antibodies. Fortunately, there are ongoing clinical trials on oligoclonal antibodies at the moment.


Assuntos
Anticorpos Monoclonais , Antígeno B7-H1 , Animais , Humanos , Anticorpos Monoclonais/uso terapêutico , Antígeno B7-H1/genética , Antígeno CTLA-4/genética , Glicoproteínas , Receptor de Morte Celular Programada 1/metabolismo , Polimorfismo Genético
14.
Biol Trace Elem Res ; 201(4): 1559-1566, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35486317

RESUMO

Sodium selenite modulates the activity of lymphocytes. It negatively regulates the suppressive activity of cells and increases the immune response. In this study, we evaluated whether the regulatory T cell differentiation was modulated by sodium selenite. The percentages of CD4+CD25+Foxp3+, CD4+CD25+, and CD4+CTLA-4+ cells in CD4+ T cells cultures stimulated with IL-2 and TGF-ß in the presence or absence of selenium, in the form of sodium selenite (2.0×10-6M), were evaluated by flow cytometry. The mRNA expression of TET2/3 enzymes and IL-10 was analyzed by RT-qPCR and the levels of IL-10 were measured by an ELISA. We observed a decrease in CD4+CD25+Foxp3+ and CD4+CTLA-4+ cells in presence of selenium. However, normal percentages were reached again after selenium removal. An increase in CD4+CTL4-4+ cells was detected in selenium-primed cell cultures in absence of IL-2 and TGF-ß. In addition, we observed a decrease in TET3 in presence of selenium. Finally, we observed an augment in IL-10 transcription and protein levels and relative expression of TET2 in cultures exposed to selenium. We suggest that selenium reversibly affects the regulatory T cell differentiation in vitro. Likewise, selenium may modulate Treg percentages promoting optimal immune responses and, at the same time, the expression of specific suppressor molecules.


Assuntos
Interleucina-10 , Selênio , Linfócitos T Reguladores/metabolismo , Selenito de Sódio/farmacologia , Selenito de Sódio/metabolismo , Antígeno CTLA-4/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Diferenciação Celular , Fatores de Transcrição Forkhead/metabolismo , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismo
15.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12938, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447687

RESUMO

Brucellosis has become a global zoonotic disease, seriously endangering the health of people all over the world. Vaccination is an effective strategy for protection against Brucella infection in livestock in developed countries. However, current vaccines are pathogenic to humans and pregnant animals, which limits their use. Therefore, it is very important to improve the safety and immune protection of Brucella vaccine. In this study, different bioinformatics approaches were carried out to predict the physicochemical properties, T/B epitope, and tertiary structure of Omp2b and Omp31. Then, these two proteins were sequentially linked, and the Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) variable region was fused to the N-terminal of the epitope sequence. In addition, molecular docking was performed to show that the structure of the fusion protein vaccine had strong affinity with B7 (B7-1, B7-2). This study showed that the designed vaccine containing CTLA-4 had high potency against Brucella, which could provide a reference for the future development of efficient brucellosis vaccines.

16.
Rev. Assoc. Med. Bras. (1992, Impr.) ; Rev. Assoc. Med. Bras. (1992, Impr.);69(7): e20230371, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1449106

RESUMO

SUMMARY OBJECTIVE: The expression of cytotoxic T lymphocyte-associated antigen 4, E-cadherin, and CD44 in the area of tumor budding was investigated in breast carcinomas in our study. METHODS: Tumor budding was counted at the invasive margins in 179 breast carcinomas. To understand the microenvironment of tumor budding, we examined the expression status of the immune checkpoint molecules such as cytotoxic T lymphocyte-associated antigen 4, E-cadherin, and CD44. RESULTS: Tumors were separated into low (≤5) and high tumor budding groups (>5) based on the median budding number. Lymphovascular, perineural invasion, and the number of metastatic lymph nodes were significantly higher in high-grade budding tumors (p=0.001, p<0.001, and p=0.019, respectively). Tumor-infiltrating lymphocytes were significantly higher in tumors without tumor buddings (p<0.001). When the number of budding increases by one unit, overall survival decreases by 1.07 times (p=0.013). Also, it increases the risk of progression by 1.06 times (p=0.048). In high tumor budding groups, the cytotoxic T lymphocyte-associated antigen 4 staining percentage of lymphocytes was significantly higher (p=0.026). With each increase in the number of buds, an increase in the percentage of cytotoxic T lymphocyte-associated antigen 4 staining was seen in lymphocytes in the microenvironment of TB (p=0.034). CONCLUSION: Tumor budding could predict poor prognosis in breast carcinomas, and anti-cytotoxic T lymphocyte-associated antigen 4 immunotherapies may be beneficial in patients with high tumor budding tumors.

17.
São Paulo; s.n; 2023. 87 p. tab, ilus.
Tese em Português | Inca | ID: biblio-1445013

RESUMO

Introdução: Apesar dos grandes avanços no tratamento sistêmico com as terapias anti-VGFR e os CPIs, os pacientes com CCRm ainda são tratados da mesma forma. Há apenas fatores clínicos e laboratoriais prognósticos, mas não preditivos de resposta, como já existem em outros tumores. A busca de biomarcadores falhou em todos os estudos de fase III que ditam as terapias atuais, representando uma área de grande desafio no tratamento dos CCRm. O entendimento da heterogeneidade, não somente intratumoral no tumor primário, como também nas metástases, torna este desafio ainda maior. Onde poucos estudos analisaram biomarcadores nas metástases. Materiais e Métodos: Foram analisados dados de 60 pacientes com CCRccm tratados no A.C.Camargo Cancer Center. O propósito desta análise foi estudar a expressão imunohistoquímica de PD-1, PD-L1 e CTLA-4 em tecido de metástase de carcinoma de células claras renal e sua eventual associação com desfechos clínicos e prognóstico na doença. Resultados: Para a análise de sobrevida global, a ausência de nefrectomia, existência de metástase óssea e metástase em tecido mole conferiram um prognóstico ruim aos pacientes analisados. Com relação a análise de sobrevida livre de progressão as variáveis grau ISUP e metástase em tecido mole conferiram um pior prognóstico aos pacientes analisados. Com relação as variáveis clínicas, para a análise de sobrevida global, os pacientes que apresentaram KPS < 80 apresentaram prognóstico pior. Com relação a análise de sobrevida livre de progressão, os pacientes que apresentaram as variáveis de KPS < 80 e hipercalcemia apresentaram um pior prognóstico. Foi observado significância estatística para o marcador molecular PD-1 para a análise de sobrevida global, as amostras sem a expressão a expressão de PD-1 apresentaram mediana de 73,9 meses, enquanto os pacientes que apresentaram expressão deste biomarcador não atingiram a mediana (p=0,044). Conclusão: Quando avaliadas na metástase de carcinoma de células claras renal a expressão imuno-histoquímica de PD-1 tem papel prognóstico para sobrevida global, porém o marcador não se mostrou ser uma variável de importância prognóstica independente das outras variáveis. A expressão de IHQ de PD-L1 e CLTA-4 em CCRccm não demonstrou ter um papel prognóstico.


Introduction: Despite major advances in systemic treatment with anti-VGFR therapies and checkpoint inhibitors (CPIs), patients with metastatic renal cell carcinoma (mRCC) are still treated in the same way. There are only prognostic clinical and laboratory factors, but not predictive or selector of therapies, as they already exist in other tumors. The search for biomarkers has failed in all phase III studies that dictate current therapies, representing an area of great challenge in the treatment of mRCC. The understanding of heterogeneity, not only intratumoral in the primary tumor, but also in metastases, makes this challenge even greater. Few studies have analyzed biomarkers in metastasis. Materials and Methods: Data from 60 patients with mCRC treated at the A.C.Camargo Cancer Center were analyzed. The purpose of this analysis was to study the IHQ expression of PD-1, PD-L1 and CTLA-4 in renal clear cell carcinoma metastasis tissue and their eventual association with clinical outcomes and prognosis in the disease. Results: For the analysis of overall survival, the absence of nephrectomy, presence of bone metastasis and metastasis in soft tissue conferred a poor prognosis to the patients analyzed. Regarding the analysis of progression-free survival, the variables ISUP grade and soft tissue metastasis conferred a worse prognosis to the patients analyzed. Regarding clinical variables, for the analysis of overall survival, patients who had KPS < 80 had a worse prognosis. Regarding the analysis of progression-free survival, patients who presented the variables of KPS < 80 and hypercalcemia had a worse prognosis. Statistical significance was observed for the molecular marker PD-1 for the analysis of overall survival, patients who lost PD-1 expression had a median of 73.9 months, while patients who showed expression of this biomarker did not reach the median (p =0.044). Conclusion: When evaluated in renal clear cell carcinoma metastasis, the immunohistochemical expression of PD-1 has a prognostic role for overall survival, but the biomarker was not shown to be a variable of prognostic importance independent of the other variables. IHQ expression of PD-L1 and CLTA-4 in CCRccm has not been shown to have a prognostic role


Assuntos
Carcinoma de Células Renais , Antígeno B7-H1 , Antígeno CTLA-4 , Receptor de Morte Celular Programada 1 , Neoplasias Renais , Metástase Neoplásica , Biomarcadores , Análise de Sobrevida
18.
An. bras. dermatol ; An. bras. dermatol;97(6): 710-715, Nov.-Dec. 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1403200

RESUMO

Abstract Background: Vitiligo is characterized by an autoimmune response targeting melanocytes, thus resulting in skin depigmentation. There are several genetic components involved in the development of vitiligo, of which various gene polymorphisms are currently considered as risk factors. For example, the CTLA4 (T-lymphocyte antigen 4) +49A/G (rs231775) and CT60 (rs3087243) gene variants have been associated with a predisposition for autoimmune diseases in different populations; however, their involvement in the development of vitiligo remains controversial. Objective: We evaluated the association between vitiligo and the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants in a Mexican population. Methods: A total of 116 vitiligo patients and 117 control subjects from northeast Mexico were included in the study and analyzed through PCR-RFLP to determine whether there is an association between vitiligo and CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants. Results: No statistical difference was observed for both gene polymorphisms between vitiligo patients and controls (p > 0.05). Otherwise, vitiligo activity, family history of vitiligo, personal history of autoimmune diseases, or sex did not show any difference (p > 0.05). Conclusion: As suggested by the analysis of a northeastern Mexican population, the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants do not constitute a risk factor in the development of vitiligo.

19.
An Bras Dermatol ; 97(6): 710-715, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36163113

RESUMO

BACKGROUND: Vitiligo is characterized by an autoimmune response targeting melanocytes, thus resulting in skin depigmentation. There are several genetic components involved in the development of vitiligo, of which various gene polymorphisms are currently considered as risk factors. For example, the CTLA4 (T-lymphocyte antigen 4) +49A/G (rs231775) and CT60 (rs3087243) gene variants have been associated with a predisposition for autoimmune diseases in different populations; however, their involvement in the development of vitiligo remains controversial. OBJECTIVE: We evaluated the association between vitiligo and the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants in a Mexican population. METHODS: A total of 116 vitiligo patients and 117 control subjects from northeast Mexico were included in the study and analyzed through PCR-RFLP to determine whether there is an association between vitiligo and CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants. RESULTS: No statistical difference was observed for both gene polymorphisms between vitiligo patients and controls (p > 0.05). Otherwise, vitiligo activity, family history of vitiligo, personal history of autoimmune diseases, or sex did not show any difference (p > 0.05). CONCLUSION: As suggested by the analysis of a northeastern Mexican population, the CTLA4 +49A/G (rs231775) and CT60 (rs3087243) gene variants do not constitute a risk factor in the development of vitiligo.


Assuntos
Doenças Autoimunes , Hipopigmentação , Vitiligo , Antígeno CTLA-4/genética , Estudos de Casos e Controles , Frequência do Gene/genética , Predisposição Genética para Doença , Humanos , México , Polimorfismo de Nucleotídeo Único/genética , Vitiligo/genética
20.
Front Cell Dev Biol ; 10: 851032, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433707

RESUMO

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that block CTLA-4, PD-1, or PD-L1 and induce the activation of the immune system against cancer. Despite the efficacy of ICIs, which has improved the oncotherapy for patients with a variety of malignancies, several immune-related adverse events (irAEs) have been described, including those affecting the heart. Cardiac irAEs after ICI therapies, including myocarditis, can become life-threatening, and their pathogenic mechanisms remain unclear. Here, a systematic analysis was performed regarding the potential immune mechanisms underlying cardiac irAEs based on the immune adverse events induced by the ICIs: 1) recruitment of CD4+ and CD8+ T cells, 2) autoantibody-mediated cardiotoxicity, and 3) inflammatory cytokines. Furthermore, the impact of dual therapies in ICI-induced cardiac irAEs and the potential risk factors are reviewed. We propose that self-antigens released from cardiac tissues or cancer cells and the severity/advancement of cancer disease have an important role in ICI cardiotoxicity.

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