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1.
J Immunol ; 210(5): 568-579, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602929

RESUMO

T cells are central to the adaptive immune response against Trypanosoma cruzi infection. In chronic Chagas disease (CCD), circulating parasite-specific memory T cells show reduced functionality and increased expression of inhibitory receptors as a result of persistent antigenic stimulation. This phenotype has been linked to progression of cardiac pathology, whereas the presence of polyfunctional T cells shows association with therapeutic success. In this study, we demonstrate that T. cruzi-specific human CD4+ T cells can be identified by their expression of OX40 and CD25 upon in vitro stimulation. We characterized the expression of the inhibitory receptors T cell immunoreceptor with Ig and ITIM domains (TIGIT), T cell Ig and mucin-domain containing-3 (TIM-3), and lymphocyte activation gene 3 (LAG-3) in CD4+ T cells from CCD patients with and without cardiac alterations. Our results show that, independently of their clinical stage, CCD patients present an increased frequency of CD4+ T cells expressing TIGIT in comparison with non-T. cruzi-infected donors. Exposure to parasite Ags increases the expression of TIM-3 in CD4+ T cells from CCD patients, especially in those with cardiac compromise. Upregulation of LAG-3 was also detected in CCD individuals without cardiac manifestations, predominantly within the subpopulation of cells that did not become activated upon stimulation. Further differences were found between groups in the coexpression of these receptors. Blockade of each individual receptor did not affect activation or the production of IFN-γ and IL-10 by CD4+ T cells in response to parasite Ags. Our results suggest a role for TIGIT, TIM-3, and LAG-3 in the modulation of inflammatory phenomena thought to ultimately lead to tissue damage and cardiac pathology.


Assuntos
Linfócitos T CD4-Positivos , Doença de Chagas , Humanos , Receptor Celular 2 do Vírus da Hepatite A , Receptor de Morte Celular Programada 1/metabolismo , Receptores Imunológicos
2.
Int J Mol Sci ; 25(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38256275

RESUMO

Chagas disease is caused by the parasite Trypanosoma cruzi. In humans, it evolves into a chronic disease, eventually resulting in cardiac, digestive, and/or neurological disorders. In the present study, we characterized a novel T. cruzi antigen named Tc323 (TcCLB.504087.20), recognized by a single-chain monoclonal antibody (scFv 6B6) isolated from the B cells of patients with cardiomyopathy related to chronic Chagas disease. Tc323, a ~323 kDa protein, is an uncharacterized protein showing putative quinoprotein alcohol dehydrogenase-like domains. A computational molecular docking study revealed that the scFv 6B6 binds to an internal domain of Tc323. Immunofluorescence microscopy and Western Blot showed that Tc323 is expressed in the main developmental forms of T. cruzi, localized intracellularly and exhibiting a membrane-associated pattern. According to phylogenetic analysis, Tc323 is highly conserved throughout evolution in all the lineages of T. cruzi so far identified, but it is absent in Leishmania spp. and Trypanosoma brucei. Most interestingly, only plasma samples from patients infected with T. cruzi and those with mixed infection with Leishmania spp. reacted against Tc323. Collectively, our findings demonstrate that Tc323 is a promising candidate for the differential serodiagnosis of chronic Chagas disease in areas where T. cruzi and Leishmania spp. infections coexist.


Assuntos
Doença de Chagas , Leishmania , Trypanosoma cruzi , Humanos , Simulação de Acoplamento Molecular , Filogenia , Doença de Chagas/diagnóstico , Anticorpos Monoclonais
3.
Immunology ; 169(2): 185-203, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36567491

RESUMO

Antigen-specific T cells are central to the adaptive immune response against T. cruzi infection and underpin the efficacy of on-going vaccine strategies. In this context, the present study focuses on T-cell assays that define the parasite-specificity on the basis of upregulation of TCR stimulation-induced surface markers. For this purpose, we tested different dual marker combinations (OX40, CD25, CD40L, CD137, CD69, PD-L1, CD11a, CD49d, HLA-DR, CD38) to reliably identify activated CD4+ and CD8+ T-cell populations from PBMCs of chronic Chagas disease (CCD) patients after 12 or 24 h of stimulation with T. cruzi lysate. Results demonstrated that activation-induced markers (AIM) assays combining the expression of OX40, CD25, CD40L, CD137, CD69 and/or PD-L1 surface markers are efficient at detecting T. cruzi-specific CD4+ T cells in CCD patients, in comparison to non-infected donors, after both stimulation times. For CD8+ T cells, only PD-L1/OX40 after 24 h of antigen exposure resulted to be useful to track a parasite-specific response. We also demonstrated that the agnostic activation is mediated by different T. cruzi strains, such as Dm28c, CL Brener or Sylvio. Additionally, we successfully used this approach to identify the phenotype of activated T lymphocytes based on the expression of CD45RA and CCR7. Overall, our results show that different combinations of AIM markers represent an effective and simple tool for the detection of T. cruzi-specific CD4+ and CD8+ T cells.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Linfócitos T CD8-Positivos , Antígeno B7-H1 , Ligante de CD40 , Doença de Chagas/diagnóstico
4.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675007

RESUMO

Endogenous human retroviruses (ERVs) are remnants of exogenous retroviruses that have integrated into the human genome. Using publicly available RNA-seq data from 63 cervical cancer patients, we investigated the expression of ERVs in cervical cancers. Four aspects of cervical cancer were investigated: patient ancestral background, tumor HPV type, tumor stage and patient survival. Between the racial subgroups, 74 ERVs were significantly differentially expressed, with Black Americans having 30 upregulated and 44 downregulated (including MER21C, HERV9-int, and HERVH-int) ERVs when compared to White Americans. We found that 3313 ERVs were differentially expressed between HPV subgroups, including MER41A, HERVH-int and HERVK9. There were 28 downregulated (including MLT1D and HERVH-int) and 61 upregulated (including MER41A) ERVs in locally advanced-stage compared to early-stage samples. Tissue microarrays of cervical cancer patients were used to investigate the protein expression of ERVs with protein coding potential (i.e., HERVK and ERV3). Significant differences in protein expression of ERV3 (p = 0.000905) were observed between early-stage and locally advanced-stage tumors. No significant differential expression at the protein level was found for HERVK7 (p = 0.243). We also investigated a prognostic model, supplementing a baseline prediction model using FIGO stage, age and HPV positivity with ERVs data. The expression levels of all ERVs in the HERVd were input into a Lasso-Cox proportional hazards model, developing a predictive 67-ERV panel. When ERVs expression levels were supplemented with the clinical data, a significant increase in prognostic power (p = 9.433 × 10-15) relative to that obtained with the clinical parameters alone (p = 0.06027) was observed. In summary, ERV RNA expression in cervical cancer tumors is significantly different among racial cohorts, HPV subgroups and disease stages. The combination of the expression of certain ERVs in cervical cancers with clinical factors significantly improved prognostication compared to clinical factors alone; therefore, ERVs may serve as future prognostic biomarkers and therapeutic targets. Novelty and Impact: When endogenous retroviral (ERV) expression signatures were combined with currently employed clinical prognosticators of relapse of cervical cancer, the combination outperformed prediction models based on clinical prognosticators alone. ERV expression signatures in tumor biopsies may therefore be useful to help identify patients at greater risk of recurrence. The novel ERV expression signatures or adjacent genes possibly impacted by ERV expression described here may also be targets for the development of future therapeutic interventions.


Assuntos
Retrovirus Endógenos , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Retrovirus Endógenos/genética , Neoplasias do Colo do Útero/genética , Infecções por Papillomavirus/genética , Recidiva Local de Neoplasia/genética , RNA
5.
J Immunol ; 204(6): 1571-1581, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32060134

RESUMO

T cell-mediated immune response plays a crucial role in controlling Trypanosoma cruzi infection and parasite burden, but it is also involved in the clinical onset and progression of chronic Chagas' disease. Therefore, the study of T cells is central to the understanding of the immune response against the parasite and its implications for the infected organism. The complexity of the parasite-host interactions hampers the identification and characterization of T cell-activating epitopes. We approached this issue by combining in silico and in vitro methods to interrogate patients' T cells specificity. Fifty T. cruzi peptides predicted to bind a broad range of class I and II HLA molecules were selected for in vitro screening against PBMC samples from a cohort of chronic Chagas' disease patients, using IFN-γ secretion as a readout. Seven of these peptides were shown to activate this type of T cell response, and four out of these contain class I and II epitopes that, to our knowledge, are first described in this study. The remaining three contain sequences that had been previously demonstrated to induce CD8+ T cell response in Chagas' disease patients, or bind HLA-A*02:01, but are, in this study, demonstrated to engage CD4+ T cells. We also assessed the degree of differentiation of activated T cells and looked into the HLA variants that might restrict the recognition of these peptides in the context of human T. cruzi infection.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Cardiomiopatia Chagásica/imunologia , Epitopos de Linfócito T/imunologia , Trypanosoma cruzi/imunologia , Antígenos de Protozoários/metabolismo , Argentina , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/imunologia , Cardiomiopatia Chagásica/sangue , Cardiomiopatia Chagásica/parasitologia , Simulação por Computador , ELISPOT , Epitopos de Linfócito T/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Celular , Memória Imunológica , Testes de Liberação de Interferon-gama , Ativação Linfocitária , Masculino , Trypanosoma cruzi/metabolismo
6.
Rev Panam Salud Publica ; 46: e207, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36519067

RESUMO

Objective: To develop a tool that measures levels of adherence to antiretroviral treatment (ART) in resource-poor settings, based on a combination of four methods for measuring adherence. Methods: Retrospective review of 500 medical records of people living with HIV, randomly selected from October 2017 to January 2020. Adherence to ART was measured by combining four measurement methods (coverage of prescribed ART, ART picked up at pharmacies, viral load, and self-reported adherence). Chi-squared tests were performed with p<0.05 for statistically significant differences and logistic binary regression to identify the probability of optimal and suboptimal adherence. Spearman tests were performed for correlation of categories, and Cronbach's alpha was used to measure the internal consistency of the tool. Results: We obtained 497 adherence scores. Of these, 307 (61.8%) users qualified as adherent, 141 (28.4%) as semi-adherent, and 49 (9.8%) as non-adherent. A higher probability of optimal adherence was found in groups aged 60 years and older (odds ratio [OR]: 1.6; CI95%: 0.8-3.5), with no difference between men and women (OR: 0.9; CI95%: 0.7-1.4). Spearman's test reported a relationship (r = 0.8) between viral load levels and final score, and Cronbach's alpha yielded modest internal consistency (α = 0.7). Conclusions: A tool was developed to measure adherence to ART in a resource-poor environment. The tool shows modest levels of internal consistency and a strong correlation between viral load and adherence.


Objetivo: Desenvolver uma ferramenta para medir os níveis de adesão à terapia antirretroviral (TARV) em um ambiente de poucos recursos, com base na combinação de quatro métodos de medição de adesão. Métodos: Revisão retrospectiva de 500 prontuários de pessoas que vivem com HIV, selecionadas aleatoriamente de outubro de 2017 a janeiro de 2020. A adesão à TARV foi medida pela combinação de quatro métodos (porcentagem de cobertura da TARV prescrita, coleta de TARV na farmácia, nível de carga viral e adesão autorrelatada). Foram realizados testes de qui-quadrado com P < 0,05 para diferenças estatisticamente significativas e regressão logística binária para identificar probabilidades de adesão ótima e subótima. Foram realizados testes de Spearman para a correlação de categorias e alfa de Cronbach para medir a consistência interna do instrumento. Resultados: Foram obtidos 497 índices de adesão. Entre eles, 307 (61,8%) usuários foram classificados como aderentes, 141 (28,4%) como semiaderentes e 49 (9,8%) como não aderentes. Foi encontrada maior probabilidade de adesão ótima nos grupos de 60 anos ou mais (odds ratio [OR]: 1,6; IC95%: 0,8-3,5), sem diferença entre homens e mulheres (OR: 0,9; IC95%: 0,7-1,4). O teste de Spearman constatou uma relação (r = 0,8) entre os níveis de carga viral e a pontuação final, e o teste alfa de Cronbach mostrou uma consistência interna modesta (α = 0,7). Conclusões: Foi desenvolvida uma ferramenta para medir a adesão em um ambiente de poucos recursos. A ferramenta apresenta níveis modestos de consistência interna e forte correlação de categoria entre carga viral e adesão.

7.
Rep Pract Oncol Radiother ; 27(4): 684-690, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36196421

RESUMO

Background: Benign diseases include tumours or localized growths with low potential for progression. The use of radiotherapy (RT) at a low dose (LD) or intermediate dose for benign pathologies has been widely proposed and studied. Currently, the use of RT is limited mainly to hyperproliferative and inflammatory diseases as a first or second line of treatment. Materials and methods: This was a retrospective, observational and descriptive study conducted in the Radiotherapy Unit of the Oncology Service of the General Hospital of Mexico "Dr. Eduardo Liceaga" from January 2, 2016, to December 31, 2020. Patients diagnosed with benign pathology and treated with RT were included. The response to treatment was recorded based on the imaging study report and/or clinical review that determined control of the disease, and toxicity was recorded based on the RTOG evaluation for acute effects and CTCAE V. 4.0 for chronic effects. Results: The records of 222 patients were analysed. The mean follow-up duration was 31.53 months (range 6-61), and the median was 24 months. Of all of the analysed pathologies that were treated with RT, keloid scars predominated in 112 patients (50.5%), and paragangliomas predominated in 72 patients (32.4%); the other patients were treated for rare pathologies. The prescribed dose was dependent on the diagnosis, with the mean dose being 31.63 Gy (1500-6000 cGy) and the median being 2000 cGy. Most of the cases of acute and chronic toxicity were grades 1 and 2, and a disease response was achieved in 94.1% of the patients. Conclusion: Our series shows that for cases of benign pathology, RT offers acceptable toxicity, improves quality of life and yields a good response, achieving disease control. These results suggest the inclusion of inflammatory pathology among the indications for treatment.

8.
Immunology ; 163(1): 46-59, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33410127

RESUMO

Trypanosoma cruzi cytosolic tryparedoxin peroxidase (c-TXNPx) is a 2-Cys peroxiredoxin (Prx) with an important role in detoxifying host cell oxidative molecules during parasite infection. c-TXNPx is a virulence factor, as its overexpression enhances parasite infectivity and resistance to exogenous oxidation. As Prxs from other organisms possess immunomodulatory properties, we studied the effects of c-TXNPx in the immune response and analysed whether the presence of the peroxidatic cysteine is necessary to mediate these properties. To this end, we used a recombinant c-TXNPx and a mutant version (c-TXNPxC52S) lacking the peroxidatic cysteine. We first analysed the oligomerization profile, oxidation state and peroxidase activity of both proteins by gel filtration, Western blot and enzymatic assay, respectively. To investigate their immunological properties, we analysed the phenotype and functional activity of macrophage and dendritic cells and the T-cell response by flow cytometry after injection into mice. Our results show that c-TXNPx, but not c-TXNPxC52S, induces the recruitment of IL-12/23p40-producing innate antigen-presenting cells and promotes a strong specific Th1 immune response. Finally, we studied the cellular and humoral immune response developed in the context of parasite natural infection and found that only wild-type c-TXNPx induces proliferation and high levels of IFN-γ secretion in PBMC from chronic patients without demonstrable cardiac manifestations. In conclusion, we demonstrate that c-TXNPx possesses pro-inflammatory properties that depend on the presence of peroxidatic cysteine that is essential for peroxidase activity and quaternary structure of the protein and could contribute to rational design of immune-based strategies against Chagas disease.


Assuntos
Doença de Chagas/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Peroxidases/metabolismo , Proteínas de Protozoários/metabolismo , Células Th1/metabolismo , Trypanosoma cruzi/enzimologia , Imunidade Adaptativa , Adulto , Idoso , Animais , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Feminino , Interações Hospedeiro-Parasita , Humanos , Imunidade Inata , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Mutação , Peroxidases/genética , Peroxidases/imunologia , Estrutura Quaternária de Proteína , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Relação Estrutura-Atividade , Células Th1/imunologia , Células Th1/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia
9.
Mol Carcinog ; 58(3): 398-410, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30378175

RESUMO

Wnt pathway activation maintains the cancer stem cell (CSC) phenotype and promotes tumor progression, making it an attractive target for anti-cancer therapy. Wnt signaling at the tumor and tumor microenvironment (TME) front have not been investigated in depth in head and neck squamous cell carcinoma (HNSCC). In a cohort of 48 HNSCCs, increased Wnt signaling, including Wnt genes (AXIN2, LGR6, WISP1) and stem cell factors (RET, SOX5, KIT), were associated with a more advanced clinical stage. Key Wnt pathway proteins were most abundant at the cancer epithelial-stromal boundary. To investigate these observations, we generated three pairs of cancer-cancer associated fibroblast (CAF) cell lines derived from the same HNSCC patients. 3D co-culture of cancer spheres and CAFs mimicked these in vivo interactions, and using these we observed increased expression of Wnt genes (eg, WNT3A, WNT7A, WNT16) in both compartments. Of these Wnt ligands, we found Wnt3a, and less consistently Wnt16, activated Wnt signaling in both cancer cells and CAFs. Wnt activation increased CSC characteristics like sphere formation and invasiveness, which was further regulated by the presence of CAFs. Time lapse microscopy also revealed preferential Wnt activation of cancer cells. Wnt inhibitors, OMP-18R5 and OMP-54F28, significantly reduced growth of HNSCC patient-derived xenografts and suppressed Wnt activation at the tumor epithelial-stromal boundary. Taken together, our findings suggest that Wnt signaling is initiated in cancer cells which then activate CAFs, and in turn perpetuate a paracrine signaling loop. This suggests that targeting Wnt signaling in the TME is essential.


Assuntos
Carcinoma de Células Escamosas/patologia , Comunicação Celular , Neoplasias de Cabeça e Pescoço/patologia , Células-Tronco Neoplásicas/patologia , Microambiente Tumoral , Via de Sinalização Wnt , Animais , Apoptose , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Immunology ; 155(3): 367-378, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29972690

RESUMO

Trypanosoma cruzi, the aetiological agent of Chagas disease, has a highly efficient detoxification system to deal with the oxidative burst imposed by its host. One of the antioxidant enzymes involved is the cytosolic tryparedoxin peroxidase (c-TXNPx), which catalyses the reduction to hydrogen peroxide, small-chain organic hydroperoxides and peroxynitrite. This enzyme is present in all parasite stages, and its overexpression renders parasites more resistant to the oxidative defences of macrophages, favouring parasite survival. This work addressed the study of the specific humoral and cellular immune response triggered by c-TXNPx in human natural infection. Thus, sera and peripheral blood mononuclear cells (PBMC) were collected from chronically infected asymptomatic and cardiac patients, and non-infected individuals. Results showed that levels of IgG antibodies against c-TXNPx were low in sera from individuals across all groups. B-cell epitope prediction limited immunogenicity to a few, small regions on the c-TXNPx sequence. At a cellular level, PBMC from asymptomatic and cardiac patients proliferated and secreted interferon-γ after c-TXNPx stimulation, compared with mock control. However, only proliferation was higher in asymptomatic patients compared with cardiac and non-infected individuals. Furthermore, asymptomatic patients showed an enhanced frequency of CD19+ CD69+ cells upon exposure to c-TXNPx. Overall, our results show that c-TXNPx fails to induce a strong immune response in natural infection, being measurable only in those patients without any clinical symptoms. The low impact of c-TXNPx in the human immune response could be strategic for parasite survival, as it keeps this crucial antioxidant enzyme activity safe from the mechanisms of adaptive immune response.


Assuntos
Imunidade Adaptativa , Doença de Chagas/imunologia , Peroxidases/imunologia , Proteínas de Protozoários/imunologia , Trypanosoma cruzi/imunologia , Adulto , Idoso , Anticorpos Antiprotozoários/imunologia , Doença de Chagas/patologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade
11.
Mol Carcinog ; 57(11): 1651-1663, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30129680

RESUMO

In this report, we describe in detail the evolving procedures to optimize humanized mouse cohort generation, including optimal conditioning, choice of lineage for engraftment, threshold for successful engraftment, HNSCC tumor implantation, and immune and stroma cell analyses. We developed a dual infusion protocol of human hematopoietic stem and progenitor cells (HSPCs) and mesenchymal stem cells (MSCs), leading to incremental human bone marrow engraftment, and exponential increase in mature peripheral human immune cells, and intratumor homing that includes a more complete lineage reconstitution. Additionally, we have identified practical rules to predict successful HSPC/MSC expansion, and a peripheral human cell threshold associated with bone marrow engraftment, both of which will optimize cohort generation and management. The tremendous advances in immune therapy in cancer have made the need for appropriate and standardized models more acute than ever, and therefore, we anticipate that this manuscript will have an immediate impact in cancer-related research. The need for more representative tools to investigate the human tumor microenvironment (TME) has led to the development of humanized mouse models. However, the difficulty of immune system engraftment and minimal human immune cell infiltration into implanted xenografts are major challenges. We have developed an improved method for generating mismatched humanized mice (mHM), using a dual infusion of human HSPCs and MSCs, isolated from cord blood and expanded in vitro. Engraftment with both HSPCs and MSCs produces mice with almost twice the percentage of human immune cells in their bone marrow, compared to mice engrafted with HSPCs alone, and yields 9- to 38-fold higher levels of mature peripheral human immune cells. We identified a peripheral mHM blood human B cell threshold that predicts an optimal degree of mouse bone marrow humanization. When head and neck squamous cell carcinoma (HNSCC) tumors are implanted on the flanks of HSPC-MSC engrafted mice, human T cells, B cells, and macrophages infiltrate the stroma of these tumors at 2- to 8-fold higher ratios. In dually HSPC-MSC engrafted mice we also more frequently observed additional types of immune cells, including regulatory T cells, cytotoxic T cells, and MDSCs. Higher humanization was associated with in vivo response to immune-directed therapy. The complex immune environment arising in tumors from dually HSPC-MSC engrafted mice better resembles that of the originating patient's tumor, suggesting an enhanced capability to accurately recapitulate a human TME.


Assuntos
Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço/patologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Biomarcadores , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunofenotipagem , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Knockout , Transplante Heterólogo
12.
Adv Exp Med Biol ; 1015: 59-74, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29080021

RESUMO

The most outstanding manifestations of the plastic capacities of brain circuits and their neuronal and synaptic components in the adult CNS are learning and memory. A reduced number of basic plastic mechanisms underlie learning capacities at many levels and regions of the brain. The interoceptive system is no exception, and some of the most studied behavioral changes that involve learning and memory engage the interoceptive pathways at many levels of their anatomical and functional organization.In this chapter, we will review four examples of learning, mostly in rats, where the interoceptive system has a role. In the case of conditioned taste aversion, the interoceptive system is of outstanding importance. In drug addiction, the role of the insular cortex - the highest level of the interoceptive system- is unusual and complex, as many forebrain regions are engaged by the process of addiction. In the third example, neophobia, the gustatory region of the insular cortex plays a major role. Finally, the role of different areas of the insular cortex in different processes of aversive memory, particularly fear conditioning, will be reviewed.


Assuntos
Córtex Cerebral/fisiologia , Interocepção/fisiologia , Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Aprendizagem da Esquiva/fisiologia , Ratos
13.
Mem Inst Oswaldo Cruz ; 111(6): 365-71, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27223650

RESUMO

This study aimed to evaluate well-documented diagnostic antigens, named B13, 1F8 and JL7 recombinant proteins, as potential markers of seroconversion in treated chagasic patients. Prospective study, involving 203 patients treated with benznidazole, was conducted from endemic areas of northern Argentina. Follow-up was possible in 107 out of them and blood samples were taken for serology and PCR assays before and 2, 3, 6, 12, 24 and 36 months after treatment initiation. Reactivity against Trypanosoma cruzi lysate and recombinant antigens was measured by ELISA. The rate of decrease of antibody titers showed nonlinear kinetics with an abrupt drop within the first three months after initiation of treatment for all studied antigens, followed by a plateau displaying a low decay until the end of follow-up. At this point, anti-B13, anti-1F8 and anti-JL7 titers were relatively close to the cut-off line, while anti-T. cruzi antibodies still remained positive. At baseline, 60.8% (45/74) of analysed patients tested positive for parasite DNA by PCR and during the follow-up period in 34 out of 45 positive samples (75.5%) could not be detected T. cruzi DNA. Our results suggest that these antigens might be useful as early markers for monitoring antiparasitic treatment in chronic Chagas disease.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Adulto , Antígenos de Protozoários/imunologia , Argentina , Doença de Chagas/sangue , Doença Crônica , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
14.
Cell Physiol Biochem ; 33(6): 1745-57, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24923359

RESUMO

BACKGROUND/AIMS: we have investigated whether cultured cardiomyocytes of the cell line HL-1 have the ability to perform regulatory volume responses both in hypotonic and hypertonic conditions. Furthermore, we characterized those regulatory responses and studied the effects of bumetanide and DIDS in volume regulation of HL-1 cells. METHODS: we used a light scattering system to measure the transient volume changes of HL-1 cells when subjected to osmotic challenge. RESULTS: We found that HL-1 cells correct for their volume excess by undergoing regulatory volume decrease (RVD), and also respond to hypertonic stress with a regulatory volume increase (RVI). Rate of RVD was 0.08 ± 0.04 intensity/min, and rate of RVI was 0.09 ± 0.01 intensity/min. Volume recovery was 83.68 ± 5.73 % for RVD and 92.3 ± 2.3 % for RVI. Bumetanide 50 µM inhibited volume recovery, from 92.3 ± 2.3 % (control) to 24.6 ± 8.8 % and reduced the rate of RVI from 0.070 ± 0.020 intensity/min (control) to 0.010 ± 0.005 intensity/min. 50 µM DIDS reduced volume recovery to 42.93 ± 7.7 % and rate of RVI, to 0.03 ± 0.01 intensity/min. CONCLUSIONS: these results suggest that bumetanide- and DIDS-sensitive mechanisms are involved in the RVI of HL-1 cells, which points to the involvement of the Na(+)/K(+)/2Cl(-) cotransporter and Cl(-)/bicarbonate exchanger in RVI, respectively.


Assuntos
Tamanho Celular/efeitos dos fármacos , Soluções Hipertônicas/farmacologia , Soluções Hipotônicas/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Bumetanida/farmacologia , Linhagem Celular , Diuréticos/farmacologia , Camundongos , Miócitos Cardíacos/citologia , Osmose/efeitos dos fármacos , Fatores de Tempo
15.
Am J Pathol ; 182(1): 29-40, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23142379

RESUMO

Galectin-1 (Gal-1), an evolutionarily conserved ß-galactoside-binding lectin, plays essential roles in the control of inflammation and neovascularization. Although identified as a major component of the contractile apparatus of cardiomyocytes, the potential role of Gal-1 in modulating heart pathophysiology is uncertain. Here, we aimed to characterize Gal-1 expression and function in the infarcted heart. Expression of Gal-1 was substantially increased in the mouse heart 7 days after acute myocardial infarction (AMI) and in hearts from patients with end-stage chronic heart failure. This lectin was localized mainly in cardiomyocytes and inflammatory infiltrates in peri-infarct areas, but not in remote areas. Both simulated hypoxia and proinflammatory cytokines selectively up-regulated Gal-1 expression in mouse cardiomyocytes, whereas anti-inflammatory cytokines inhibited expression of this lectin or had no considerable effect. Compared with their wild-type counterpart, Gal-1-deficient (Lgals1(-/-)) mice showed enhanced cardiac inflammation, characterized by increased numbers of macrophages, natural killer cells, and total T cells, but reduced frequency of regulatory T cells, leading to impaired cardiac function at baseline and impaired ventricular remodeling 7 days after nonreperfused AMI. Treatment of mice with recombinant Gal-1 attenuated cardiac damage in reperfused AMI. Taken together, our results indicate a protective role for Gal-1 in normal cardiac homeostasis and postinfarction remodeling by preventing cardiac inflammation. Thus, Gal-1 treatment represents a potential novel strategy to attenuate heart failure in AMI.


Assuntos
Galectina 1/fisiologia , Infarto do Miocárdio/fisiopatologia , Miocardite/metabolismo , Remodelação Ventricular/fisiologia , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Células Cultivadas , Citocinas/farmacologia , Feminino , Galectina 1/biossíntese , Galectina 1/farmacologia , Galectina 1/uso terapêutico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Mediadores da Inflamação/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Miocardite/etiologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteínas Recombinantes/uso terapêutico , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto Jovem
16.
Cancer Res Commun ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984891

RESUMO

Chromobox 2 (CBX2), an epigenetic reader and component of Polycomb Repressor Complex 1 (PRC1), is highly expressed in >75% of high-grade serous carcinoma (HGSC). Increased CBX2 expression is associated with poorer survival, while CBX2 knockdown leads to improved chemotherapy sensitivity. In an HGSC immune competent murine model, knockdown of CBX2 decreased tumor progression. We sought to explore the impact of modulation of CBX2 on the tumor immune microenvironment (TIME), understanding that the TIME plays a critical role in disease progression and development of therapy resistance. Exploration of existing datasets demonstrated that elevated CBX2 expression significantly correlated with the specific immune cell types in the TIME. RNA-seq and pathway analysis of differentially expressed genes demonstrated immune signature enrichment. Confocal microscopy and co-culture experiments found modulation of CBX2 leads to increased recruitment and infiltration of macrophages. Flow cytometry of macrophages cultured with CBX2 overexpressing cells showed increased M2-like macrophages and decreased phagocytosis activity. Cbx2 knockdown in the Trp53, Brca2 null ID8 syngeneic murine model (ID8 Trp53-/- Brca2-/-) led to decreased tumor progression compared to control. NanoString Immuno-Oncology Panel analysis suggested knock down in Cbx2 shifts immune cell composition, with an increase in macrophages. Multispectral immunohistochemistry further confirmed an increase in macrophage infiltration. Increased CBX2 expression leads to recruitment and polarization of pro-tumor macrophages and targeting CBX2 may serve to modulate the TIME to enhance the efficacy of immune therapies.

17.
Reproduction ; 145(4): 335-43, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23401597

RESUMO

Fragile X mental retardation protein (FMRP) belongs to a small family of RNA-binding proteins. Its absence or inactivity is responsible for fragile X syndrome, the most common cause of inherited mental retardation. Despite its ubiquitous expression, FMRP function and expression remain almost understudied in non-neuronal tissues, though previous studies on germline development during oogenesis may suggest a special function of this protein also in ovarian tissue. In addition, the well-documented association of FMR1 premutation state with fragile X-related premature ovarian insufficiency adds interest to the role of FMRP in ovarian physiology. The aim of the present work was to investigate the expression of Fmr1 mRNA and its protein, FMRP, at different stages of rat follicular development. By immunohistochemical studies we demonstrated FMRP expression in granulosa, theca and germ cells in all stages of follicular development. In addition, changes in Fmr1 expression, both at the protein and mRNA levels, were observed. FMRP levels increased upon follicular development while preantral and early antral follicles presented similar levels of Fmr1 transcripts with decreased expression in preovulatory follicles. These observations suggest that Fmr1 expression in the ovary is regulated at different and perhaps independent levels. In addition, our results show expression of at least four different isoforms of FMRP during all stages of follicular growth with expression patterns that differ from those observed in brain and testis. Our study shows a regulated expression of Fmr1, both at mRNA and protein levels, during rat follicular development.


Assuntos
Proteína do X Frágil da Deficiência Intelectual/genética , Folículo Ovariano/metabolismo , Animais , Feminino , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Twin Res Hum Genet ; 16(1): 336-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23394193

RESUMO

The Southern California Twin Register at the University of Southern California (USC) was initiated in 1984 and continues to provide an important resource for studies investigating genetic and environmental influences on human behavior. This article provides an update on the current register and its potential for future twin studies using recruitment through school district databases and voter records. An overview is also provided for an ongoing longitudinal twin study investigating the development of externalizing psychopathology from childhood to young adulthood, the USC Study of Risk Factors for Antisocial Behavior. Characteristics of the twins and their families are presented, including recruitment and participation rates, as well as attrition analyses and a summary of key findings to date.


Assuntos
Transtorno da Personalidade Antissocial/epidemiologia , Doenças em Gêmeos/epidemiologia , Genética Comportamental , Transtornos Mentais/epidemiologia , Sistema de Registros , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Idoso , Transtorno da Personalidade Antissocial/genética , Transtorno da Personalidade Antissocial/psicologia , California/epidemiologia , Criança , Doenças em Gêmeos/genética , Doenças em Gêmeos/psicologia , Feminino , Interação Gene-Ambiente , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/genética , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Prospectivos , Fatores de Risco , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/estatística & dados numéricos , Adulto Jovem
19.
J Circadian Rhythms ; 11(1): 8, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23962056

RESUMO

BACKGROUND: Intracellular calcium is a biochemical messenger that regulates part of the metabolic adaptations in the daily fed-fast cycle. The aim of this study was to characterize the 24-h variations of the liver ryanodine and IP3 receptors (RyR and IP3R) as well as of the endoplasmic-reticulum and plasma-membrane Ca2+-ATPases (SERCA and PMCA) in daytime restricted feeding protocol. METHODS: A biochemical and immunohistochemical approach was implemented in this study: specific ligand-binding for RyR and IP3R, enzymatic activity (SERCA and PMCA), and protein levels and zonational hepatic-distribution were determined by immunoblot and immunohistochemistry respectively under conditions of fasting, feeding, and temporal food-restriction. RESULTS: Binding assays and immunoblots for IP3R1 and 2 showed a peak at the light/dark transition in the ad-libitum (AL) group, whereas in the restricted-feeding (RF) group the peak shifted towards the food-access time. In the case of RyR binding experiments, both AL and RF groups showed a modest elevation during the dark period, with the RF rats exhibiting increased binding in response to feeding. The AL group showed 24-h rhythmicity in SERCA level; in contrast, RF group showed a pronounced amplitude elevation and a peak phase-shift during the light-period in SERCA level and activity. The activity of PMCA was constant along day in both groups; PMCA1 levels showed a 24-h rhythmicity in the RF rats (with a peak in the light period), meanwhile PMCA4 protein levels showed rhythmicity in both groups. The fasted condition promoted an increase in IP3R binding and protein level; re-feeding increased the amount of RyR; neither the activity nor expression of SERCA and PMCA protein was affected by fasting-re-feeding conditions. Histochemical experiments showed that the distribution of the Ca2+-handling proteins, between periportal and pericentral zones of the liver, varied with the time of day and the feeding protocol. CONCLUSIONS: Our findings show that RF influences mainly the phase and amplitude of hepatic IP3R and SERCA rhythms as well as discrete zonational distribution for RyR, IP3Rs, SERCA, and PMCA within the liver acinus, suggesting that intracellular calcium dynamics could be part of the rheostatic adaptation of the liver due to diurnal meal entrainment/food entrained oscillator expression.

20.
J Natl Cancer Inst ; 115(11): 1392-1403, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37389416

RESUMO

BACKGROUND: The programmed cell death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) are validated cancer targets; however, emerging mechanisms and impact of PD-L1 intracellular signaling on cancer behavior are poorly understood. METHODS: We investigated the cancer cell intrinsic role of PD-L1 in multiple patient-derived models in vitro and in vivo. PD-L1 overexpression, knockdown, and PD-L1 intracellular domain (PD-L1-ICD) deletion (Δ260-290PD-L1) models were assessed for key cancer properties: clonogenicity, motility, invasion, and immune evasion. To determine how PD-L1 transduces signals intracellularly, we used the BioID2 platform to identify the PD-L1 intracellular interactome. Both human papillomavirus-positive and negative patient-derived xenografts were implanted in NOD-scid-gamma and humanized mouse models to investigate the effects of recombinant PD-1, anti-PD-L1, and anti-signal transducer and activator of transcription 3 (STAT3) in vivo. RESULTS: PD-L1 intracellular signaling increased clonogenicity, motility, and invasiveness in multiple head and neck squamous cell carcinoma (HNSCC) models, and PD-1 binding enhanced these effects. Protein proximity labeling revealed the PD-L1 interactome, distinct for unbound and bound PD-1, which initiated cancer cell-intrinsic signaling. PD-L1 binding partners interleukin enhancer binding factors 2 and 3 (ILF2-ILF3) transduced their effect through STAT3. Δ260-290PD-L1 disrupted signaling and reversed pro-growth properties. In humanized HNSCC in vivo models bearing T-cells, PD-1 binding triggered PD-L1 signaling, and dual PD-L1 and STAT3 inhibition were required to achieve tumor control. CONCLUSIONS: Upon PD-1 binding, the PD-L1 extracellular and intracellular domains exert a synchronized effect to promote immune evasion by inhibiting T-cell function while simultaneously enhancing cancer cell-invasive properties.


Assuntos
Antígeno B7-H1 , Neoplasias de Cabeça e Pescoço , Animais , Humanos , Camundongos , Neoplasias de Cabeça e Pescoço/genética , Camundongos Endogâmicos NOD , Receptor de Morte Celular Programada 1 , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
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