RESUMO
Approaches to reverse or limit regulatory T cell (Treg) insufficiency are of great interest for development of immunotherapeutic treatments for autoimmune patients, including type 1 diabetes. Treg insufficiency is heavily implicated in the progression of autoimmune diabetes in the NOD mouse model and is characterized by defects in Treg numbers, development, and/or function. Utilizing a Treg-centric screen, we show that intraislet Tregs have a uniquely dysfunctional phenotype, hallmarked by an almost complete lack of neuropilin-1 (Nrp1), a cell surface receptor required to maintain Treg stability. Intraislet Nrp1- Tregs exhibit hallmark features of fragility, including reduced suppressive capacity, decreased CD73 and Helios, and increased Rorγt and Tbet. Intraislet Nrp1- Tregs also exhibit decreased Foxp3 expression on a per cell basis, suggesting that Nrp1 may also be required for long-term Treg stability. Mechanistically, Treg-restricted augmentation of Nrp1 expression limited the onset of autoimmune diabetes in NOD mice suggesting that Nrp1 critically impacts intraislet Treg function. Transcriptional analysis showed that Nrp1 restoration led to an increase in markers and pathways of TCR signaling, survival, and suppression, and when Nrp1 protein expression is examined by cellular indexing of transcriptomes and epitopes by sequencing, significant differences were observed between Nrp1+ and Nrp1- Tregs in all tissues, particularly in markers of Treg fragility. This translated into substantive differences between Nrp1+ and Nrp1- Tregs that afforded the former with a competitive advantage in the islets. Taken together, these data suggest that maintenance of Nrp1 expression and signaling on Tregs limits diabetes onset and may serve as a strategy to combat Treg insufficiency in autoimmune disease.
Assuntos
Diabetes Mellitus Tipo 1 , Neuropilina-1 , Linfócitos T Reguladores , Animais , Camundongos , Diabetes Mellitus Tipo 1/imunologia , Proteínas de Ligação a DNA , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Camundongos Endogâmicos NOD , Neuropilina-1/genética , Neuropilina-1/metabolismo , Linfócitos T Reguladores/imunologia , Fatores de TranscriçãoRESUMO
The regulatory T cell master transcription factor, Forkhead box P3 (Foxp3), has been detected in cancer cells; however, its role in breast tumor pathogenesis remains controversial. Here we assessed Foxp3 tumor intrinsic effects in experimental breast cancer using a Foxp3 binder peptide (P60) that impairs Foxp3 nuclear translocation. Cisplatin upregulated Foxp3 expression in HER2+ and triple-negative breast cancer (TNBC) cells. Foxp3 inhibition with P60 enhanced chemosensitivity and reduced cell survival and migration in human and murine breast tumor cells. We also developed an adenoviral vector encoding P60 (Ad.P60) that efficiently transduced breast tumor cells, reduced cell viability and migration, and improved the cytotoxic response to cisplatin. Conditioned medium from transduced breast tumor cells contained lower levels of IL-10 and improved the activation of splenic lymphocytes. Intratumoral administration of Ad.P60 in breast-tumor-bearing mice significantly reduced tumor infiltration of Tregs, delayed tumor growth, and inhibited the development of spontaneous lung metastases. Our results suggest that Foxp3 exerts protumoral intrinsic effects in breast cancer cells and that gene-therapy-mediated blockade of Foxp3 could constitute a therapeutic strategy to improve the response of these tumors to standard treatment.
Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Cisplatino/farmacologia , Linfócitos T Reguladores , Peptídeos/farmacologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismoRESUMO
Transcription factors are multidomain proteins with specific DNA binding and regulatory domains. In the human FoxP subfamily (FoxP1, FoxP2, FoxP3, and FoxP4) of transcription factors, a 90 residue-long disordered region links a Leucine Zipper (ZIP)-known to form coiled-coil dimers-and a Forkhead (FKH) domain-known to form domain swapping dimers. We used replica exchange discrete molecular dynamics simulations, single-molecule fluorescence experiments, and other biophysical tools to understand how domain tethering in FoxP1 impacts dimerization at ZIP and FKH domains and how DNA binding allosterically regulates their dimerization. We found that domain tethering promotes FoxP1 dimerization but inhibits a FKH domain-swapped structure. Furthermore, our findings indicate that the linker mediates the mutual organization and dynamics of ZIP and FKH domains, forming closed and open states with and without interdomain contacts, thus highlighting the role of the linkers in multidomain proteins. Finally, we found that DNA allosterically promotes structural changes that decrease the dimerization propensity of FoxP1. We postulate that, upon DNA binding, the interdomain linker plays a crucial role in the gene regulatory function of FoxP1.
Assuntos
DNA , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dimerização , DNA/química , Domínios Proteicos , Regulação da Expressão Gênica , Proteínas Repressoras/química , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição Forkhead/química , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismoRESUMO
Human Papillomavirus (HPV) persistence leads to the chronification of cervical inflammation, where HLA-G and Foxp3; immunomodulatory molecules, may contribute to the aggravation of the lesion and cancerization. Here, we evaluated the synergic effect of these two molecules in the worsening of the lesion in presence of HPV infection. Hundred and eighty (180) women cervical cells and biopsies were collected for (i) HLAG Sanger sequencing and gene expression, and (ii) HLA-G and Foxp3 molecule expressions by immunohistochemistry. 53 women were HPV+ against 127 women HPV-. HPV+ women were more at risk of having cytological changes (p ≤ 0.0123), histological changes (p < 0.0011), and cervical lesion (p = 0.0004). The HLA-G + 3142CC genotype predisposed women to infection (p = 0.0190), while HLA-G + 3142C and +3035 T alleles were associated with HLA-G5 transcript expression. Both sHLA-G (p = 0.030) and Foxp3 (p = 0.0002) proteins were higher in cervical lesion as well as in high-grade lesion. In addition, sHLA-G+ cells were positively correlated to Foxp3+ cells in presence of HPV infection and in cervical grade II/III injuries. In conclusion, HPV may use HLA-G and Foxp3 as a way of host immune escape contributing to the persistence of infection and inflammation, leading to the cervical lesion and the worsening of lesions.
Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Antígenos HLA-G/genética , Neoplasias do Colo do Útero/genética , Displasia do Colo do Útero/genética , Inflamação , Fatores de Transcrição Forkhead/genética , Papillomaviridae/genéticaRESUMO
BACKGROUND: Trafficking of regulatory T cells (Tregs) modulates the inflammatory response after kidney transplantation (KTx). There is scarce information on whether circulating and intragraft Tregs are similarly affected by immunosuppressive drugs and the type of deceased kidney donor. METHODS: FOXP3 gene expression was measured in the pretransplant kidney biopsies (PIBx) from donors who met extended (ECD) and standard (SCD) criteria donors. In the third month after KTx, the patients were divided according to tacrolimus (Tac) or everolimus (Eve) and the type of kidney they had received. FOXP3 gene expression in the peripheral blood (PB) and kidney biopsies (Bx) was analyzed using real-time polymerase chain reaction. RESULTS: FOXP3 gene expression in the PIBx was higher in ECD kidneys. FOXP3 gene expression in the PB and Bx was greater in Eve- than in Tac-treated patients. However, SCD recipients treated with Eve (SCD/Eve) had higher FOXP3 expression than ECD/Eve. CONCLUSION: Pretransplant kidney biopsies from ECD kidneys had higher FOXP3 gene expression than SCD, and the use of Eve may affect the expression of the FOXP3 gene only in SCD kidneys.
Assuntos
Sobrevivência de Enxerto , Sirolimo , Humanos , Sirolimo/uso terapêutico , Estudos Retrospectivos , Tacrolimo/uso terapêutico , Doadores de Tecidos , Everolimo/efeitos adversos , Rim , Fatores de Transcrição Forkhead/genética , Serina-Treonina Quinases TOR , Expressão Gênica , BiópsiaRESUMO
Condyloma acuminata (CA) is a benign proliferative disease mainly affecting in non-keratinized epithelia. Most cases of CA are caused by low-risk human papillomavirus (HPV), mainly HPV 6 and 11. The aim of the current study was to highlight the candidate genes and pathways associated with immune alterations in individuals who did not spontaneously eliminate the virus and, thus, develop genital warts. Paraffin-embedded condyloma samples (n = 56) were analyzed by immunohistochemistry using antibodies against CD1a, FOXP3, CD3, CD4, CD8, and IFN-γ. The immunomarkers were chosen based on the evaluation of the innate and adaptive immune pathways using qPCR analysis of 92 immune-related genes, applying a TaqMan Array Immune Response assay in HPV 6 or HPV 11 positive samples (n = 27). Gene expression analysis revealed 31 differentially expressed genes in CA lesions. Gene expression validation revealed upregulation of GZMB, IFNG, IL12B, and IL8 and downregulation of NFATC4 and IL7 in CA samples. Immunohistochemical analysis showed increased FOXP3, IFN-γ, CD1a, and CD4 expression in CA than in the control tissue samples. In contrast, CD3 and CD8 expression was decreased in CA lesion samples. Increased levels of pro-inflammatory cytokines in HPV-positive patients compared with HPV-negative patients seem to reflect the elevated immunogenicity of HPV-positive CA lesions. Host defense against HPV begins during the early stages of the innate immune response and is followed by activation of T lymphocytes, which are mainly represented by CD4+ and regulatory T cells. The low CD8+ T cell count in CA may contribute to this recurrent behavior. Additional studies are needed to elucidate the mechanism of host defense against HPV infection in CA.
Assuntos
Condiloma Acuminado , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/genética , Condiloma Acuminado/genética , Condiloma Acuminado/patologia , Citocinas , Imunidade , Fatores de Transcrição Forkhead/genética , Papillomaviridae/genéticaRESUMO
BACKGROUND: Primary open-angle glaucoma (POAG), the world's main cause of irreversible blindness, is an asymptomatic and neurodegenerative disease of multifactorial etiology with ethnic and geographic disparities. Multiethnic genome-wide association studies (GWAS) identified single nucleotide variants (SNVs) in ATXN2, FOXC1, and TXNRD2 loci as risk factors for POAG pathophysiology and/or endophenotypes. The aim of this case-control study was to investigate the association of the variants rs7137828 (ATXN2), rs2745572 (FOXC1), and rs35934224 (TXNRD2), as risk factors for POAG development, additionally to rs7137828 association with glaucoma clinical parameters in a Brazilian cohort from the Southeast and South regions. METHODS: This investigation comprised 506 cases and 501 controls. Variants rs2745572 and rs35934224 were genotyped through TaqMan® assays and validated by Sanger sequencing. Variant rs7137828 was genotyped exclusively by Sanger sequencing. RESULTS: The primary research outcome revealed that the variant rs7137828 (ATXN2) was associated with an increased risk for the development of POAG in the presence of the TT genotype compared to the CC genotype (p = 0.006; Odds Ratio [OR] = 1.717; Confidence Interval [CI] 95% = 1.169-2.535). There was no significant association of rs2745572 and rs35934224 genotypes with POAG. The CT genotype of the rs7137828 was associated with the vertical cup-to-disk ratio (VCDR) (p = .023) but not with the age at diagnosis or the mean deviation. CONCLUSION: Our data indicate the rs7137828 associated with increased risk for the development of POAG and VCDR in a Brazilian cohort. If validated in additional populations, these findings may enable the development of relevant strategies for early diagnosis of glaucoma in the future.
Assuntos
Glaucoma de Ângulo Aberto , Doenças Neurodegenerativas , Humanos , Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/diagnóstico , Estudo de Associação Genômica Ampla , Estudos de Casos e Controles , Brasil/epidemiologia , Genótipo , Fatores de Risco , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Fatores de Transcrição Forkhead/genética , Ataxina-2/genética , Tiorredoxina Redutase 2/genéticaRESUMO
Human T lymphotropic virus 1 (HTLV-1) is a retrovirus associated with inflammatory diseases, including HTLV-1-associated myelopathy (HAM), and host genetic factors may be involved in disease evolution. The forkhead Box P3 (FOXP3) transcription factor is linked to homeostasis of the immune system, and the presence of polymorphisms in the promoter region of the FOXP3 gene should reflect its expression levels and consequent activation of regulatory T cells, which may contribute to severe inflammatory disorders, such as HAM. This study evaluated the rs2232365 polymorphism (-924 A/G) located in the promoter region of the FOXP3 gene and its association with HAM. Forty DNA samples from asymptomatic carriers and 25 samples from HAM patients were used, in addition to 130 control samples. The polymorphism was genotyped by conducting real-time polymerase chain reaction (PCR) (quantitative PCR [qPCR]) on extracted DNA. The proviral loads (PVLs) and CD4+ and CD8+ T lymphocyte counts were determined by qPCR and FACSCalibur flow cytometry, respectively. The PVLs, CD4+ T lymphocyte concentrations, and tumor necrosis factor-α dosages were considered predictive factors of the clinical profiles of HTLV-1 infection, all of which had higher levels in the HAM group. Carriers of the GG genotype for the polymorphism rs2232365 had high PVLs and CD4+ T lymphocyte concentrations.
Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Humanos , Paraparesia Espástica Tropical/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Polimorfismo de Nucleotídeo Único , Infecções por HTLV-I/genética , Fatores de Transcrição Forkhead/genética , Carga Viral , Provírus/genética , Provírus/metabolismoRESUMO
BACKGROUND: Granulosa cell ovarian tumor (GCT) is characterized by a pathognomonic mutation in the FOXL2 gene (402 C > G) that leads to an overactivation of steroidogenesis. CYP17 is a key enzyme in such process and can be inhibited by ketoconazole. METHODS: We designed a phase II clinical trial to assess the efficacy of ketoconazole in advanced GCT and conducted several in vitro studies to support the clinical findings. RESULTS: From October 1st 2012 to January 31st 2014, six evaluable patients were recruited in ten hospitals of the Spanish Group for Transversal Oncology and Research in Orphan and Infrequent Tumors" (GETTHI). FOXL2 (402C > G) mutation was confirmed in three; two cases were wild type and it could not be assessed in one. No objective response by RECIST was observed, but five cases achieved stable disease longer than 12 months. Median progression-free survival was 14.06 months (CI 95% 5.43-22.69) for the whole study population (3.38 and 13.47 months for wild-type cases and 14.06, 20.67 and 26.51 for those with confirmed FOXL2 mutation). Median overall survival was 22·99 months (CI 95% 8.99-36.99). In vitro assays confirmed the activity of ketoconazole in this tumor and suggested potential synergisms with other hormone therapies. CONCLUSION: Ketoconazole has shown activity in advanced GCT in clinical and in vitro studies. Based on these data, an orphan designation was granted by the European Medicines Agency for ketoconazole in GCT (EU/3/17/1857). GOV IDENTIFIER: NCT01584297.
Assuntos
Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Cetoconazol/uso terapêutico , Esteroide 17-alfa-Hidroxilase/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Inibidores Enzimáticos , Células da Granulosa/metabolismo , Células da Granulosa/patologiaRESUMO
The Forkhead box P2 (FOXP2) encodes for a transcription factor with a broad role in embryonic development. It is especially represented among GWAS hits for neurodevelopmental disorders and related traits, including attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, neuroticism, and risk-taking behaviors. While several functional studies are underway to understand the consequences of FOXP2 variation, this study aims to expand previous findings to clinically and genetically related phenotypes and neuroanatomical features among subjects with ADHD. The sample included 407 adults with ADHD and 463 controls. Genotyping was performed on the Infinium PsychArray-24 BeadChip, and the FOXP2 gene region was extracted. A gene-wide approach was adopted to evaluate the combined effects of FOXP2 variants (n = 311) on ADHD status, severity, comorbidities, and personality traits. Independent risk variants presenting potential functional effects were further tested for association with cortical surface areas in a subsample of cases (n = 87). The gene-wide analyses within the ADHD sample showed a significant association of the FOXP2 gene with harm avoidance (P = 0.001; PFDR = 0.015) and nominal associations with hyperactivity symptoms (P = 0.026; PFDR = 0.130) and antisocial personality disorder (P = 0.026; PFDR = 0.130). An insertion/deletion variant (rs79622555) located downstream of FOXP2 was associated with the three outcomes and nominally with the surface area of superior parietal and anterior cingulate cortices. Our results extend and refine previous GWAS findings pointing to a role of FOXP2 in several neurodevelopment-related phenotypes, mainly those involving underlying symptomatic domains of self-regulation and inhibitory control. Taken together, the available evidence may constitute promising insights into the puzzle of the FOXP2-related pathophysiology.