RAFAEL RIBEIRO ALMEIDA

(Fonte: Lattes)
Índice h a partir de 2011
13
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/19 - Laboratório de Histocompatibilidade e Imunidade Celular, Hospital das Clínicas, Faculdade de Medicina

Resultados de Busca

Agora exibindo 1 - 10 de 16
  • article 45 Citação(ões) na Scopus
    Disease Tolerance and Pathogen Resistance Genes May Underlie Trypanosoma cruzi Persistence and Differential Progression to Chagas Disease Cardiomyopathy
    (2018) CHEVILLARD, Christophe; NUNES, Joao Paulo Silva; FRADE, Amanda Farage; ALMEIDA, Rafael Ribeiro; PANDEY, Ramendra Pati; NASCIMENTO, Marilda Savoia; KALIL, Jorge; CUNHA-NETO, Edecio
    Chagas disease is caused by infection with the protozoan Trypanosoma cruzi and affects over 8 million people worldwide. In spite of a powerful innate and adaptive immune response in acute infection, the parasite evades eradication, leading to a chronic persistent infection with low parasitism. Chronically infected subjects display differential patterns of disease progression. While 30% develop chronic Chagas disease cardiomyopathy (CCC)-a severe inflammatory dilated cardiomyopathy-decades after infection, 60% of the patients remain disease-free, in the asymptomatic/indeterminate (ASY) form, and 10% develop gastrointestinal disease. Infection of genetically deficient mice provided a map of genes relevant for resistance to T. cruzi infection, leading to the identification of multiple genes linked to survival to infection. These include pathogen resistance genes (PRG) needed for intracellular parasite destruction, and genes involved in disease tolerance (protection against tissue damage and acute phase death-DTG). All identified DTGs were found to directly or indirectly inhibit IFN-gamma production or Th1 differentiation. We hypothesize that the absolute need for DTG to control potentially lethal IFN-gamma PRG activity leads to T. cruzi persistence and establishment of chronic infection. IFN-gamma production is higher in CCC than ASY patients, and is the most highly expressed cytokine in CCC hearts. Key DTGs that downmodulate IFN-gamma, like IL-10, and Ebi3/IL27p28, are higher in ASY patients. Polymorphisms in PRG and DTG are associated with differential disease progression. We thus hypothesize that ASY patients are disease tolerant, while an imbalance of DTG and IFN-gamma PRG activity leads to the inflammatory heart damage of CCC.
  • article 25 Citação(ões) na Scopus
    Broad and Cross-Clade CD4(+) T-Cell Responses Elicited by a DNA Vaccine Encoding Highly Conserved and Promiscuous HIV-1 M-Group Consensus Peptides
    (2012) ALMEIDA, Rafael Ribeiro; ROSA, Daniela Santoro; RIBEIRO, Susan Pereira; SANTANA, Vinicius Canato; KALLAS, Esper Georges; SIDNEY, John; SETTE, Alessandro; KALIL, Jorge; CUNHA-NETO, Edecio
    T-cell based vaccine approaches have emerged to counteract HIV-1/AIDS. Broad, polyfunctional and cytotoxic CD4(+) T-cell responses have been associated with control of HIV-1 replication, which supports the inclusion of CD4(+) T-cell epitopes in vaccines. A successful HIV-1 vaccine should also be designed to overcome viral genetic diversity and be able to confer immunity in a high proportion of immunized individuals from a diverse HLA-bearing population. In this study, we rationally designed a multiepitopic DNA vaccine in order to elicit broad and cross-clade CD4(+) T-cell responses against highly conserved and promiscuous peptides from the HIV-1 M-group consensus sequence. We identified 27 conserved, multiple HLA-DR-binding peptides in the HIV-1 M-group consensus sequences of Gag, Pol, Nef, Vif, Vpr, Rev and Vpu using the TEPITOPE algorithm. The peptides bound in vitro to an average of 12 out of the 17 tested HLA-DR molecules and also to several molecules such as HLA-DP, -DQ and murine IA(b) and IA(d). Sixteen out of the 27 peptides were recognized by PBMC from patients infected with different HIV-1 variants and 72% of such patients recognized at least 1 peptide. Immunization with a DNA vaccine (HIVBr27) encoding the identified peptides elicited IFN-gamma secretion against 11 out of the 27 peptides in BALB/c mice; CD4(+) and CD8(+) T-cell proliferation was observed against 8 and 6 peptides, respectively. HIVBr27 immunization elicited cross-clade T-cell responses against several HIV-1 peptide variants. Polyfunctional CD4(+) and CD8(+) T cells, able to simultaneously proliferate and produce IFN-gamma and TNF-alpha, were also observed. This vaccine concept may cope with HIV-1 genetic diversity as well as provide increased population coverage, which are desirable features for an efficacious strategy against HIV-1/AIDS.
  • article 41 Citação(ões) na Scopus
    A DNA Vaccine Encoding Multiple HIV CD4 Epitopes Elicits Vigorous Polyfunctional, Long-Lived CD4(+) and CD8(+) T Cell Responses
    (2011) ROSA, Daniela Santoro; RIBEIRO, Susan Pereira; ALMEIDA, Rafael Ribeiro; MAIRENA, Eliane Conti; POSTOL, Edilberto; KALIL, Jorge; CUNHA-NETO, Edecio
    T-cell based vaccines against HIV have the goal of limiting both transmission and disease progression by inducing broad and functionally relevant T cell responses. Moreover, polyfunctional and long-lived specific memory T cells have been associated to vaccine-induced protection. CD4(+) T cells are important for the generation and maintenance of functional CD8(+) cytotoxic T cells. We have recently developed a DNA vaccine encoding 18 conserved multiple HLA-DR-binding HIV-1 CD4 epitopes (HIVBr18), capable of eliciting broad CD4(+) T cell responses in multiple HLA class II transgenic mice. Here, we evaluated the breadth and functional profile of HIVBr18-induced immune responses in BALB/c mice. Immunized mice displayed high-magnitude, broad CD4(+)/CD8(+) T cell responses, and 8/18 vaccine-encoded peptides were recognized. In addition, HIVBr18 immunization was able to induce polyfunctional CD4(+) and CD8(+) T cells that proliferate and produce any two cytokines (IFN gamma/TNF alpha, IFN gamma/IL-2 or TNF alpha/IL-2) simultaneously in response to HIV-1 peptides. For CD4(+) T cells exclusively, we also detected cells that proliferate and produce all three tested cytokines simultaneously (IFN gamma/TNF alpha/IL-2). The vaccine also generated long-lived central and effector memory CD4(+) T cells, a desirable feature for T-cell based vaccines. By virtue of inducing broad, polyfunctional and long-lived T cell responses against conserved CD4(+) T cell epitopes, combined administration of this vaccine concept may provide sustained help for CD8(+) T cells and antibody responses-elicited by other HIV immunogens.
  • article 5 Citação(ões) na Scopus
    Recurrence of COVID-19 associated with reduced T-cell responses in a monozygotic twin pair
    (2022) V, Mateus de Castro; SANTOS, Keity S.; APOSTOLICO, Juliana S.; FERNANDES, Edgar R.; ALMEIDA, Rafael R.; LEVIN, Gabriel; MAGAWA, Jhosiene Y.; NUNES, Joao Paulo S.; BRUNI, Mirian; YAMAMOTO, Marcio M.; LIMA, Ariane C.; SILVA, Monize V. R.; MATOS, Larissa R. B.; CORIA, Vivian R.; CASTELLI, Erick C.; SCLIAR, Marilia O.; KURAMOTO, Andreia; BRUNO, Fernanda R.; JACINTHO, Lucas C.; NUNES, Kelly; WANG, Jaqueline Y. T.; COELHO, Veronica P.; NETO, Miguel Mitne; MACIEL, Rui M. B.; NASLAVSKY, Michel S.; PASSOS-BUENO, Maria Rita; BOSCARDIN, Silvia B.; ROSA, Daniela S.; KALIL, Jorge; ZATZ, Mayana; CUNHA-NETO, Edecio
    Recurrence of COVID-19 in recovered patients has been increasingly reported. However, the immune mechanisms behind the recurrence have not been thoroughly investigated. The presence of neutralizing antibodies (nAbs) in recurrence/reinfection cases suggests that other types of immune response are involved in protection against recurrence. Here, we investigated the innate type I/III interferon (IFN) response, binding and nAb assays and T-cell responses to severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) with IFN gamma (IFN gamma) enzyme-linked spot assay (ELISPOT) in three pairs of young adult monozygotic (MZ) twins with previous confirmed COVID-19, one of them presenting a severe recurrence four months after the initial infection. Twin studies have been of paramount importance to comprehend the immunogenetics of infectious diseases. Each MZ twin pair was previously exposed to SARS-CoV-2, as seen by clinical reports. The six individuals presented similar overall recovered immune responses except for the recurrence case, who presented a drastically reduced number of recognized SARS-CoV-2 T-cell epitopes on ELISPOT as compared to her twin sister and the other twin pairs. Our results suggest that the lack of a broad T-cell response to initial infection may have led to recurrence, emphasizing that an effective SARS-CoV-2-specific T-cell immune response is key for complete viral control and avoidance of clinical recurrence of COVID-19.
  • article 52 Citação(ões) na Scopus
    Butyrate Attenuates Lung Inflammation by Negatively Modulating Th9 Cells
    (2019) VIEIRA, Raquel de Souza; CASTOLDI, Angela; BASSO, Paulo Jose; HIYANE, Meire Ioshie; CAMARA, Niels Olsen Saraiva; ALMEIDA, Rafael Ribeiro
    Th9 cells orchestrate allergic lung inflammation by promoting recruitment and activation of eosinophils and mast cells, and by stimulating epithelial mucus production, which is known to be mainly dependent on IL-9. These cells share developmental pathways with induced regulatory T cells that may determine the generation of one over the other subset. In fact, the FOXP3 transcription factor has been shown to bind il9 locus and repress IL-9 production. The microbiota-derived short-chain fatty acids (SCFAs) butyrate and propionate have been described as FOXP3 inducers and are known to have anti-inflammatory properties. While SCFAs attenuate lung inflammation by inducing regulatory T cells and suppressing Th2 responses, their effects on Th9 cells have not been addressed yet. Therefore, we hypothesized that SCFAs would have a protective role in lung inflammation by negatively modulating differentiation and function of Th9 cells. Our results demonstrated that butyrate is more effective than propionate in promoting FOXP3 expression and IL-9 repression. In addition, propionate was found to negatively impact in vitro differentiation of IL-13-expressing T cells. Butyrate treatment attenuated lung inflammation and mucus production in OVA-challenged mice, which presented lower frequency of lung-infiltrated Th9 cells and eosinophils. Both Th9 cell adoptive transfer and IL-9 treatment restored lung inflammation in butyrate-treated OVA-challenged mice, indicating that the anti-inflammatory effects of butyrate may rely on suppressing Th9-mediated immune responses.
  • article 27 Citação(ões) na Scopus
    miRNAs may play a major role in the control of gene expression in key pathobiological processes in Chagas disease cardiomyopathy
    (2020) LAUGIER, Laurie; FERREIRA, Ludmila Rodrigues Pinto; FERREIRA, Frederico Moraes; CABANTOUS, Sandrine; FRADE, Amanda Farage; NUNES, Joao Paulo; RIBEIRO, Rafael Almeida; BROCHET, Pauline; TEIXEIRA, Priscila Camillo; SANTOS, Ronaldo Honorato Barros; BOCCHI, Edimar A.; BACAL, Fernando; CANDIDO, Darlan da Silva; MASO, Vanessa Escolano; NAKAYA, Helder I.; KALIL, Jorge; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFN gamma, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-gamma-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy. Author summary Chronic Chagas disease cardiomyopathy (CCC), an aggressive dilated cardiomyopathy caused by Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Little is known about the molecular mechanisms responsible for its severity. Authors study the possible role of microRNAs in the regulation of gene expression in relevant pathways and pathobiological processes. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) -small RNAs that can regulate gene expression-associated to severe cardiomyopathy development. The inflammatory mediator Interferon-gamma was the most likely inducer of gene expression in CCC, and most genes belonged to the immune response, fibrosis, hypertrophy and mitochondrial metabolism. A discrete number of differentially expressed mRNAs targeted a high number of differentially expressed mRNAs in multiple processes. Moreover, several pathways had multiple targets regulated by microRNAs, suggesting synergic effect. Results suggest that microRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue.
  • article 3 Citação(ões) na Scopus
    Epigenetic regulation of transcription factor binding motifs promotes Th1 response in Chagas disease cardiomyopathy
    (2022) BROCHET, Pauline; IANNI, Barbara Maria; LAUGIER, Laurie; FRADE, Amanda Farage; NUNES, Joao Paulo Silva; TEIXEIRA, Priscila Camillo; MADY, Charles; FERREIRA, Ludmila Rodrigues Pinto; FERRE, Quentin; SANTOS, Ronaldo Honorato Barros; KURAMOTO, Andreia; CABANTOUS, Sandrine; STEFFEN, Samuel; STOLF, Antonio Noedir; POMERANTZEFF, Pablo; FIORELLI, Alfredo Inacio; BOCCHI, Edimar Alcides; PISSETTI, Cristina Wide; SABA, Bruno; CANDIDO, Darlan da Silva; DIAS, Fabricio C.; SAMPAIO, Marcelo Ferraz; GAIOTTO, Fabio Antonio; MARIN-NETO, Jose Antonio; FRAGATA, Abilio; ZANIRATTO, Ricardo Costa Fernandes; SIQUEIRA, Sergio; PEIXOTO, Giselle De Lima; RIGAUD, Vagner Oliveira-Carvalho; BACAL, Fernando; BUCK, Paula; ALMEIDA, Rafael Ribeiro; LIN-WANG, Hui Tzu; SCHMIDT, Andre; MARTINELLI, Martino; HIRATA, Mario Hiroyuki; DONADI, Eduardo Antonio; PEREIRA, Alexandre Costa; RODRIGUES JUNIOR, Virmondes; PUTHIER, Denis; KALIL, Jorge; SPINELLI, Lionel; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Chagas disease, caused by the protozoan Trypanosoma cruzi, is an endemic parasitic disease of Latin America, affecting 7 million people. Although most patients are asymptomatic, 30% develop complications, including the often-fatal Chronic Chagasic Cardiomyopathy (CCC). Although previous studies have demonstrated some genetic deregulations associated with CCCs, the causes of their deregulations remain poorly described. Based on bulk RNA-seq and whole genome DNA methylation data, we investigated the genetic and epigenetic deregulations present in the moderate and severe stages of CCC. Analysis of heart tissue gene expression profile allowed us to identify 1407 differentially expressed transcripts (DEGs) specific from CCC patients. A tissue DNA methylation analysis done on the same tissue has permitted the identification of 92 regulatory Differentially Methylated Regions (DMR) localized in the promoter of DEGs. An in-depth study of the transcription factors binding sites (TFBS) in the DMRs corroborated the importance of TFBS's DNA methylation for gene expression in CCC myocardium. TBX21, RUNX3 and EBF1 are the transcription factors whose binding motif appears to be affected by DNA methylation in the largest number of genes. By combining both transcriptomic and methylomic analysis on heart tissue, and methylomic analysis on blood, 4 biological processes affected by severe CCC have been identified, including immune response, ion transport, cardiac muscle processes and nervous system. An additional study on blood methylation of moderate CCC samples put forward the importance of ion transport and nervous system in the development of the disease.
  • article 9 Citação(ões) na Scopus
    Co-administration of plasmid-encoded granulocyte-macrophage colony-stimulating factor increases human immunodeficiency virus-1 DNA vaccine-induced polyfunctional CD4(+) T-cell responses
    (2015) SANTANA, Vinicius Canato; ALMEIDA, Rafael Ribeiro; RIBEIRO, Susan Pereira; FERREIRA, Lius Carlos de Souza; KALIL, Jorge; ROSA, Daniela Santoro; CUNHA-NETO, Edecio
    T-cell based vaccines against human immunodeficiency virus (HIV) generate specific responses that may limit both transmission and disease progression by controlling viral load. Broad, polyfunctional, and cytotoxic CD4(+) T-cell responses have been associated with control of simian immunodeficiency virus/HIV-1 replication, supporting the inclusion of CD4(+) T-cell epitopes in vaccine formulations. Plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) co-administration has been shown to induce potent CD4(+) T-cell responses and to promote accelerated priming and increased migration of antigen-specific CD4(+) T-cells. However, no study has shown whether co-immunisation with pGM-CSF enhances the number of vaccine-induced polyfunctional CD4(+) T-cells. Our group has previously developed a DNA vaccine encoding conserved, multiple human leukocyte antigen (HLA)-DR binding HIV-1 subtype B peptides, which elicited broad, polyfunctional and long-lived CD4(+) T-cell responses. Here, we show that pGM-CSF co-immunisation improved both magnitude and quality of vaccine-induced T-cell responses, particularly by increasing proliferating CD4(+) T-cells that produce simultaneously interferon-gamma, tumour necrosis factor-alpha and interleukin-2. Thus, we believe that the use of pGM-CSF may be helpful for vaccine strategies focused on the activation of anti-HIV CD4(+) T-cell immunity.
  • article 6 Citação(ões) na Scopus
    STING Signaling Drives Production of Innate Cytokines, Generation of CD8(+) T Cells and Enhanced Protection Against Trypanosoma cruzi Infection
    (2022) VIEIRA, Raquel de Souza; NASCIMENTO, Marilda Savoia; NORONHA, Isau Henrique; VASCONCELOS, Jose Ronnie Carvalho; BENVENUTI, Luiz Alberto; BARBER, Glen N.; CAMARA, Niels Olsen Saraiva; KALIL, Jorge; CUNHA-NETO, Edecio; ALMEIDA, Rafael Ribeiro
    A variety of signaling pathways are involved in the induction of innate cytokines and CD8(+) T cells, which are major players in protection against acute Trypanosoma cruzi infection. Previous data have demonstrated that a TBK-1/IRF3-dependent signaling pathway promotes IFN-beta production in response to Trypanosoma cruzi, but the role for STING, a main interactor of these proteins, remained to be addressed. Here, we demonstrated that STING signaling is required for production of IFN-beta, IL-6, and IL-12 in response to Trypanosoma cruzi infection and that STING absence negatively impacts activation of IRF-dependent pathways in response to the parasite. We reported no significant activation of IRF-dependent pathways and cytokine expression in RAW264.7 macrophages in response to heat-killed trypomastigotes. In addition, we showed that STING is essential for T. cruzi DNA-mediated induction of IFN-beta, IL-6, and IL-12 gene expression in RAW264.7 macrophages. We demonstrated that STING-knockout mice have significantly higher parasitemia from days 5 to 8 of infection and higher heart parasitism at day 13 after infection. Although we observed similar heart inflammatory infiltrates at day 13 after infection, IFN-beta, IL-12, CXCL9, IFN-gamma, and perforin gene expression were lower in the absence of STING. We also showed an inverse correlation between parasite DNA and the expression of CXCL9, IFN-gamma, and perforin genes in the hearts of infected animals at day 13 after infection. Finally, we reported that STING signaling is required for splenic IFN-beta and IL-6 expression early after infection and that STING deficiency results in lower numbers of splenic parasite-specific IFN-gamma and IFN-gamma/perforin-producing CD8(+) T cells, indicating a pivotal role for STING signaling in immunity to Trypanosoma cruzi.
  • article 35 Citação(ões) na Scopus
    IL-10-Producing Regulatory B Cells Are Decreased in Patients with Common Variable Immunodeficiency
    (2016) BARSOTTI, Nathalia Silveira; ALMEIDA, Rafael Ribeiro; COSTA, Priscilla Ramos; BARROS, Myrthes Toledo; KALIL, Jorge; KOKRON, Cristina Maria
    Common variable immunodeficiency (CVID) is the most prevalent symptomatic primary immunodeficiency in adults. CVID patients often present changes in the frequency and function of B lymphocytes, reduced number of Treg cells, chronic immune activation, recurrent infections, high incidence of autoimmunity and increased risk for malignancies. We hypothesized that the frequency of B10 cells would be diminished in CVID patients because these cells play an important role in the development of Treg cells and in the control of T cell activation and autoimmunity. Therefore, we evaluated the frequency of B10 cells in CVID patients and correlated it with different clinical and immunological characteristics of this disease. Forty-two CVID patients and 17 healthy controls were recruited for this study. Cryo-preserved PBMCs were used for analysis of T cell activation, frequency of Treg cells and characterization of B10 cells by flow cytometry. IL-10 production by sorted B cells culture and plasma sCD14 were determined by ELISA. We found that CVID patients presented decreased frequency of IL-10-producing CD24(hi)CD38(hi) B cells in different cell culture conditions and decreased frequency of IL-10-producing CD24(hi)CD27(+) B cells stimulated with CpG+PIB. Moreover, we found that CVID patients presented lower secretion of IL-10 by sorting-purified B cells when compared to healthy controls. The frequency of B10 cells had no correlation with autoimmunity, immune activation and Treg cells in CVID patients. This work suggests that CVID patients have a compromised regulatory B cell compartment which is not correlated with clinical and immunological characteristics presented by these individuals.