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1.
Braz. j. med. biol. res ; 54(12): e11610, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1345566

RESUMO

Due to the high transfusion volume, polytransfused patients with sickle cell disease (SCD) and beta-thalassemia are constantly exposed to parenterally transmitted infections. Currently, we have little information about the virome of such patients and how the virological composition might be influenced by the hemotherapy procedures that these patients receive. The objective of this study was to compare the viral diversity between these two groups with respect to the viral abundance and how it might be affected by the specific conditions of these groups. We sequenced by next-generation sequencing (NGS) and compared the virome of 30 patients with beta-thalassemia major, 45 with SCD, and 16 blood donors from the Blood Center of Ribeirão Preto, Brazil. Predominantly, commensal viruses including Torque teno virus (TTV) genotypes and human pegiviris-1 (HPgV-1) were identified in each group. Strikingly, while HPgV-1 reads were dominant in the SCD group, thalassemic patients showed high TTV abundance, expressed both in viral reads and genotypes. We speculated that the commensal virome of polytransfused patients might be influenced by the transfusion frequency and disease characteristics and that commensal viruses might be used as important genetic biomarkers for these hematological disturbances. Nevertheless, more specific studies are necessary to confirm a relationship between blood virome and transfusion treatment.

2.
Clin Transl Oncol ; 20(4): 542-549, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28905209

RESUMO

PURPOSE: The fusion gene BCR-ABL has an important role to the progression of chronic myeloid leukemia (CML) and several signaling pathways have been characterized as responsible for the terminal blastic phase (BP). However, the initial phase, the chronic phase (CP), is long lasting and there is much yet to be understood about the critical role of BCR-ABL in this phase. This study aims to evaluate transcriptional deregulation in CD34+ hematopoietic cells (CD34+ cells) from patients with untreated newly diagnosed CML compared with CD34+HC from healthy controls. METHODS: Gene expression profiling in CML-CD34 cells and CD34 cells from healthy controls were used for this purpose with emphasis on five main pathways important for enhanced proliferation/survival, enhanced self-renewal and block of myeloid differentiation. RESULTS: We found 835 genes with changed expression levels (fold change ≥ ±2) in CML-CD34 cells compared with CD34 cells. These include genes belonging to PI3K/AKT, WNT/b-catenin, SHH, NOTCH and MAPK signaling pathways. Four of these pathways converge to MYC activation. We also identified five transcripts upregulated in CD34-CML patients named OSBPL9, MEK2, p90RSK, TCF4 and FZD7 that can be potential biomarkers in CD34-CML-CP. CONCLUSION: We show several mRNAs up- or downregulated in CD34-CML during the chronic phase.


Assuntos
Biomarcadores Tumorais/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Transdução de Sinais/genética , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34 , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Via de Sinalização Wnt/genética , Adulto Jovem
3.
Bone Marrow Transplant ; 52(6): 859-862, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28287644

RESUMO

Acute GvHD (aGvHD) is a life-threatening complication of hematopoietic stem cell transplantation. Frontline therapy for aGvHD consists of corticosteroid administration. However, ∼25% of the patients have a steroid-refractory disease, a sign of poor prognosis. An alternative therapy for steroid-refractory aGvHD is infusion of mesenchymal stromal cells (MSCs). Herein, we report the results of 46 patients treated with MSC infusion as salvage therapy for steroid-refractory aGvHD III/IV (78% grade IV). Patients received a median cumulative dose of MSCs of 6.81 × 106/kg (range, 0.98-29.78 × 106/kg) in a median of 3 infusions (range, 1-7). Median time between the onset of aGvHD and the first MSC infusion was 25.5 days (range, 6-153). Of the patients, 50% (23/46) presented clinical improvement. Of these, 3 patients (13%) had complete response, 14 (61%) had partial response and 6 (26%) had transient partial response. The estimated probability of survival at 2s year was 17.4%. Only 2 patients (4.3%) presented acute transient side effects (nausea/vomiting and blurred vision) during cell infusion. No patient had late or severe side effects because of MSC infusion. These results suggest that this therapeutic modality is safe and should be considered for steroid-refractory aGvHD, especially in countries where other second-line agents are less available.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Doença Aguda , Adolescente , Adulto , Idoso , Aloenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/terapia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Esteroides/administração & dosagem , Taxa de Sobrevida
4.
Clin Exp Immunol ; 187(3): 383-398, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28008595

RESUMO

Defective apoptosis might be involved in the pathogenesis of multiple sclerosis (MS). We evaluated apoptosis-related molecules in MS patients before and after autologous haematopoietic stem cell transplantation (AHSCT) using BCNU, Etoposide, AraC and Melphalan (BEAM) or cyclophosphamide (CY)-based conditioning regimens. Patients were followed for clinical and immunological parameters for 2 years after AHSCT. At baseline, MS patients had decreased proapoptotic BAD, BAX and FASL and increased A1 gene expression when compared with healthy counterparts. In the BEAM group, BAK, BIK, BIMEL , FAS, FASL, A1, BCL2, BCLXL , CFLIPL and CIAP2 genes were up-regulated after AHSCT. With the exception of BIK, BIMEL and A1, all genes reached levels similar to controls at day + 720 post-transplantation. Furthermore, in these patients, we observed increased CD8+ Fas+ T cell frequencies after AHSCT when compared to baseline. In the CY group, we observed increased BAX, BCLW, CFLIPL and CIAP1 and decreased BIK and BID gene expressions after transplantation. At day + 720 post-AHSCT, the expression of BAX, FAS, FASL, BCL2, BCLXL and CIAP1 was similar to that of controls. Protein analyses showed increased Bcl-2 expression before transplantation. At 1 year post-AHSCT, expression of Bak, Bim, Bcl-2, Bcl-xL and cFlip-L was decreased when compared to baseline values. In summary, our findings suggest that normalization of apoptosis-related molecules is associated with the early therapeutic effects of AHSCT in MS patients. These mechanisms may be involved in the re-establishment of immune tolerance during the first 2 years post-transplantation.


Assuntos
Apoptose/genética , Proteína 5 Relacionada à Autofagia/genética , Esclerose Múltipla/genética , Adulto , Linfócitos T CD8-Positivos/efeitos dos fármacos , Ciclofosfamida/uso terapêutico , Feminino , Expressão Gênica/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Condicionamento Pré-Transplante/métodos , Transplante Autólogo/métodos , Adulto Jovem
5.
Clin Transl Oncol ; 19(1): 125-133, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27188167

RESUMO

PURPOSE: Tumor expansion is dependent on neovascularization, a process that requires sustained new vessel formation. Although the critical role of angiogenesis by endothelial sprouting in this process, controversy still prevails on whether angiogenesis involving bone marrow-derived endothelial cells, does contribute to this process. This study aims to evaluate the recruitment of bone marrow-derived cells by the melanoma tumor, including endothelial cells, and if they contribute to angiogenesis. METHODS: A chimeric mouse model of GFP bone marrow was used to induce melanoma tumors derived from murine B16-F10 cell line. These tumors were evaluated for the presence of myeloid cells (CD11b), T lymphocytes (CD3, CD4 and CD8) and endothelial cells (VEGFR2 and CD31) derived from bone marrow. RESULTS: Mice transplanted with GFP+ cells showed significant bone marrow chimerism (90.9 ± 0.87 %) when compared to the GFP transgenic mice (90.66 ± 2.1 %, p = 0.83) demonstrating successful engraftment of donor bone marrow stem/progenitor cells. Analysis of the murine melanoma tumor showed the presence of donor cells in the tumors (3.5 ± 1.7 %) and interestingly, these cells represent endothelial cells (CD31+ cells; 11.5 ± 6.85 %) and myeloid cells (CD11b+ cells; 80 ± 21 %), but also tumor-infiltrating lymphocytes (CD8+ T cells, 13.31 ± 0.2 %; CD4+ T-cells, 2.1 ± 1.2 %). Examination of the tumor endothelium by confocal microscopy suggests the presence of donor CD31+/GFP+ cells in the wall of some blood vessels. CONCLUSION: This study demonstrates that bone marrow-derived cells are recruited by the murine melanoma tumor, with myeloid cells and CD4 and CD8 T lymphocytes migrating as antitumor immune response, and endothelial cells participating of the tumor blood vessels formation.


Assuntos
Medula Óssea/patologia , Endotélio Vascular/patologia , Linfócitos do Interstício Tumoral/patologia , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/patologia , Neovascularização Patológica , Animais , Medula Óssea/metabolismo , Transplante de Medula Óssea , Endotélio Vascular/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
6.
J Clin Pathol ; 69(10): 926-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27402956

RESUMO

Despite all the knowledge, the cellular and molecular mechanisms involved in myeloproliferative neoplasm (MPN) pathophysiology remain unclear. Authors have shown galectin-1 (Gal-1) and 3 playing roles in tumour angiogenesis and fibrosis, which were correlated with poor prognosis in patients with MPN. In the present study LGALS1 and LGALS3 were differently expressed between polycythemia vera, essential thrombocythemia (ET) and primary myelofibrosis (PMF) diseases. Increased LGALS3 expression was associated with a negative JAK2 V617F status mutation in leucocytes from PMF but not in patients with ET without this mutation. However, a positive Janus kinase 2 (JAK2) V617F cell line established from patients with ET (SET-2 cells) when treated with JAK inhibitor presented high levels of LGALS3. Additionally, high LGALS1 expression was found in CD34(+) cells but not in leucocytes from patients with PMF, in absence of JAK2 V617F mutation, and also in SET-2 cells treated with JAK inhibitor. Thus, our findings indicate that differential expression of LGALS1 and/or LGALS3 in patients with MPN is linked with JAK2 V617F status mutation in these diseases and state of cell differentiation.


Assuntos
Galectina 1/genética , Galectina 3/genética , Janus Quinase 2/genética , Policitemia Vera/genética , Mielofibrose Primária/genética , Trombocitemia Essencial/genética , Adulto , Substituição de Aminoácidos , Antígenos CD34/genética , Proteínas Sanguíneas , Medula Óssea/patologia , Neoplasias da Medula Óssea/diagnóstico , Neoplasias da Medula Óssea/genética , Neoplasias da Medula Óssea/metabolismo , Linhagem Celular , Galectina 1/metabolismo , Galectina 3/metabolismo , Galectinas , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 2/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Policitemia Vera/diagnóstico , Policitemia Vera/metabolismo , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/metabolismo , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/metabolismo
7.
Transfus Med ; 26(4): 297-300, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27237104

RESUMO

OBJECTIVES: Evaluate whether poor mobilisers had delayed haematopoietic (neutrophil and platelet) recovery despite receiving similar cell dose as good mobilisers. BACKGROUND: Autologous haematopoietic progenitor cell (HPC) transplantation is indicated to treat some haematological malignancies. This procedure requires HPC mobilisation from bone marrow to peripheral blood. Cell dose is important for a fast haematological recovery. Despite being poor mobilisers, some patients can collect enough cell numbers for transplantation. RESULTS: Fifteen poor mobiliser patients (peak of CD34+ cells ≤10 µL(-1) in peripheral blood) were transplanted at our institution. Haematological recovery (neutrophil ≥ 500 µL(-1) ) in this group was compared to that observed in the group of 16 patients of good mobilisers (peak of CD34+ cells ≥20 µL(-1) in peripheral blood) who received similar cell dose (2·637 ± 0·1744 × 10(6) kg(-1) vs 2·727 ± 0·1746 × 10(6) kg(-1) ; P = 0·7177). The poor mobiliser group had neutrophil and platelet recovery later than the good mobiliser group (on day 12, range 9-14 vs day 10, range 9-22, P = 0·0381 for neutrophil, and on day 22·89 ± 11·16 and 14·08 ± 4·821, P = 0·0193 for platelet). Mortality rates and transfusion requirements were not different between the groups. CONCLUSION: Poor mobilisers have delayed neutrophil and platelet recovery after autologous HPC transplantation despite having received the same cell dose as good mobilisers.


Assuntos
Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Adulto , Idoso , Autoenxertos , Intervalo Livre de Doença , Feminino , Neoplasias Hematológicas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
8.
Braz. j. med. biol. res ; 49(5): e5420, 2016. graf
Artigo em Inglês | LILACS | ID: biblio-951672

RESUMO

Zika virus (ZIKV), a mosquito-borne flavivirus, belongs to the Flaviviridae family, genus Flavivirus. ZIKV was initially isolated in 1947 from a sentinel monkey in the Zika forest, Uganda. Little clinical importance was attributed to ZIKV, once only few symptomatic cases were reported in some African and Southeast Asiatic countries. This situation changed in 2007, when a large outbreak was registered on the Yap Island, Micronesia, caused by the Asian ZIKV lineage. Between 2013 and 2014, ZIKV spread explosively and caused many outbreaks in different islands of the Southern Pacific Ocean and in 2015 autochthonous transmission was reported in Brazil. Currently, Brazil is the country with the highest number of ZIKV-positive cases in Latin America. Moreover, for the first time after the discovery of ZIKV, the Brazilian scientists are studying the possibility for the virus to cause severe congenital infection related to microcephaly and serious birth defects due to the time-spatial coincidence of the alarming increase of newborns with microcephaly and the Brazilian ZIKV epidemic. The present review summarizes recent information for ZIKV epidemiology, clinical picture, transmission, diagnosis and the consequences of this emerging virus in Brazil.


Assuntos
Humanos , Animais , Recém-Nascido , Epidemias , Zika virus/genética , Infecção por Zika virus/embriologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Brasil/epidemiologia , Microcefalia/epidemiologia , Microcefalia/virologia
9.
Bone Marrow Transplant ; 50(3): 380-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25486582

RESUMO

Autologous hematopoietic SCT (AHSCT) has been investigated in the past as a therapeutic alternative for multiple sclerosis (MS). Despite advances in clinical management, knowledge about mechanisms involved with clinical remission post transplantation is still limited. Abnormal microRNA and gene expression patterns were described in MS and have been suggested as disease biomarkers and potential therapeutic targets. Here we assessed T- and B-cell reconstitution, microRNAs and immunoregulatory gene expression after AHSCT. Early immune reconstitution was mainly driven by peripheral homeostatic proliferation. AHSCT increased CD4(+)CD25(hi)FoxP3(+) regulatory T-cell counts and expression of CTLA-4 and GITR (glucocorticoid-induced TNFR) on CD4(+)CD25(hi) T cells. We found transient increase in exhausted PD-1(+) T cells and of suppressive CD8(+)CD28(-)CD57(+) T cells. At baseline, CD4(+) and CD8(+) T cells from MS patients presented upregulated miR-16, miR-155 and miR-142-3p and downregulated FOXP3, FOXO1, PDCD1 and IRF2BP2. After transplantation, the expression of FOXP3, FOXO1, PDCD1 and IRF2BP2 increased, reaching control levels at 2 years. Expression of miR-16, miR-155 and miR-142-3p decreased towards normal levels at 6 months post therapy, remaining downregulated until the end of follow-up. These data strongly suggest that AHSCT normalizes microRNA and gene expression, thereby improving the immunoregulatory network. These mechanisms may be important for disease control in the early periods after AHSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , MicroRNAs/biossíntese , Esclerose Múltipla/genética , Esclerose Múltipla/terapia , Condicionamento Pré-Transplante/métodos , Adulto , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Transplante Autólogo , Adulto Jovem
10.
Blood Cells Mol Dis ; 53(1-2): 47-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24629639

RESUMO

BACKGROUND: Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the presence of Philadelphia chromosome (Ph) leading to expression of a BCR-ABL1 fusion oncogene. The BCR-ABL protein has a constitutive tyrosine kinase activity which is responsible for CML pathogenesis by promoting cell apoptosis resistance; however, the cellular and molecular mechanisms associated with BCR-ABL expression and apoptosis impairment in CML leukemic cells have not been fully elucidated. METHODS: This study evaluated apoptomiRs and their predicted apoptotic genes in BCR-ABL(+) cells from patients in different phases of CML treated with tyrosine kinase inhibitor (TKI) according to their imatinib (IM) response by qPCR. Phosphotyrosine and c-ABL expressions in HL-60.BCR-ABL cells treated with TKI were done by Western blot. RESULTS: We found that dasatinib (DAS) modulated miR-let-7d, miR-let-7e, miR-15a, miR-16, miR-21, miR-130a and miR-142-3p expressions while IM modulated miR-15a and miR-130a levels. miR-16, miR-130a and miR-145 expressions were modulated by nilotinib (NIL). We observed higher miR-15a, miR-130b and miR-145; and lower miR-16, miR-26a and miR-146a expressions in CML-CP in comparison with controls. CML-AP patients showed low miR-let-7d, miR-15a, miR-16, miR-29c, miR-142-3p, miR-145, and miR-146a levels in comparison with CML-CP. We noted that the miR-26a, miR-29c, miR-130b and miR-146a expressions were downregulated in IM resistant patients in comparison with IM responsive patients. CONCLUSIONS: This study showed the modulation of apoptomiRs by BCR-ABL kinase activity and the deregulation of apoptomiRs and their predicted apoptotic target genes in different CML phases and after treatment with TK inhibitors. ApoptomiRs may be involved in the BCR-ABL(+) cell apoptosis regulation.


Assuntos
Apoptose/genética , Benzamidas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , MicroRNAs/genética , Piperazinas/farmacologia , Pirimidinas/farmacologia , Adolescente , Adulto , Idoso , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Proteínas de Fusão bcr-abl/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação/efeitos dos fármacos , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-abl/genética , Proteínas Proto-Oncogênicas c-abl/metabolismo , Pirimidinas/uso terapêutico , Resultado do Tratamento , Adulto Jovem
11.
Int J Immunogenet ; 41(3): 198-205, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24321052

RESUMO

Cytotoxic T lymphocytes and natural killer cells play a crucial role in eliminating tumour and virus-infected cells. The perforin is a key part of the arsenal that these cells use to destroy their targets. In this study, we characterized single-nucleotide polymorphisms (SNPs) located in the promoter region of the perforin gene among distinct Brazilian ethnic groups. The study was carried out by sequencing this region in three groups: European, African and Asian descents. We demonstrated for the first time the occurrence of three new polymorphisms in the promoter region of gene PRF1: 494A/G (rs78058707), 720G/A (rs75925789) and 1176C/T (rs75183511). Three other SNPs already described in the literature 63A/G (rs35401316), 112A/G (rs10999428) and 1012C/T (rs35069510) were also detected. The SNPs are distributed differently in the ethnic groups studied. The 112G allele was observed at high frequency, especially among Asian descents (48.1%). The 1012T allele was detected only among European descents, the 494G allele only among Asian descents and 1176T allele only in African descents. Based on the association between the polymorphisms described, ten new haplotypes were originated. In functional analysis, we noticed that SNPs present in most common haplotypes cannot induce significant differences in expression levels of perforin alone. In conclusion, this study demonstrates for the first time the existence of three new polymorphisms in perforin promoter and, contrary to what was stated, the presence of these SNPs does not alter the levels of protein expression.


Assuntos
Expressão Gênica/imunologia , Polimorfismo de Nucleotídeo Único , Proteínas Citotóxicas Formadoras de Poros/genética , Regiões Promotoras Genéticas , Alelos , Povo Asiático , Sequência de Bases , População Negra , Brasil , Frequência do Gene , Genética Populacional , Haplótipos , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Dados de Sequência Molecular , Perforina , Proteínas Citotóxicas Formadoras de Poros/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , População Branca
12.
Braz J Med Biol Res ; 46(8): 676-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24036939

RESUMO

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.


Assuntos
Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteopontina/metabolismo , Fosfatase Alcalina/genética , Antígenos de Diferenciação/isolamento & purificação , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Feminino , Expressão Gênica/fisiologia , Humanos , Leucócitos Mononucleares/citologia , Masculino , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteopontina/genética , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
13.
Braz. j. med. biol. res ; 46(8): 676-680, ago. 2013. graf
Artigo em Inglês | LILACS | ID: lil-684529

RESUMO

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.


Assuntos
Feminino , Humanos , Masculino , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteopontina/metabolismo , Fosfatase Alcalina/genética , Antígenos de Diferenciação/isolamento & purificação , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Expressão Gênica/fisiologia , Leucócitos Mononucleares/citologia , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteopontina/genética , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
14.
Genet Mol Res ; 12(2): 1054-60, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23613252

RESUMO

Genetic reprogramming of adult cells to generate induced pluripotent stem (iPS) cells is a new and important step in sidestepping some of the ethical issues and risks involved in the use of embryonic stem cells. iPS cells can be generated by introduction of transcription factors, such as OCT4, SOX2, KLF4, and CMYC. iPS cells resemble embryonic stem cells in their properties and differentiation potential. The mechanisms that lead to induced pluripotency and the effect of each transcription factor are not completely understood. We performed a critical evaluation of the effect of overexpressing OCT4 in mesenchymal stem cells and fibroblasts and found that OCT4 can activate the expression of other stemness genes, such as SOX2, NANOG, CMYC, FOXD3, KLF4, and ßCATENIN, which are not normally or are very weakly expressed in mesenchymal stem cells. Transient expression of OCT4 was also performed to evaluate whether these genes are affected by its overexpression in the first 48 h. Transfected fibroblast cells expressed around 275-fold more OCT4 than non-transfected cells. In transient expression, in which cells were analyzed after 48 h, we detected only the up-regulation of FOXD3, SOX2, and KLF4 genes, suggesting that these genes are the earlier targets of OCT4 in this cellular type. We conclude that forced expression of OCT4 can alter cell status and activate the pluripotent network. Knowledge gained through study of these systems may help us to understand the kinetics and mechanism of cell reprogramming.


Assuntos
Fibroblastos/metabolismo , Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Fator 4 Semelhante a Kruppel , Fator 3 de Transcrição de Octâmero/metabolismo , Transdução Genética
15.
Genet Mol Res ; 12(3): 3675-88, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23479170

RESUMO

Recombinant coagulation factor IX must be produced in mammalian cells because FIX synthesis involves translational modifications. Human cell culture-based expression of human coagulation factor IX (hFIX) is expensive, and large-scale production capacity is limited. Transgenic animals may greatly increase the yield of therapeutic proteins and reduce costs. In this study, we used a lentiviral system to obtain transgenic cells and somatic cell nuclear transfer (SCNT) to produce transgenic animals. Lentiviral vectors carrying hFIX driven by 3 bovine ß-casein promoters were constructed. Bovine epithelial mammary cells were transduced by lentivirus, selected with blasticidin, plated on extracellular matrix, and induced by lactogenic hormones; promoter activity was evaluated by quantitative PCR. Transcriptional activity of the 5.335-kb promoter was 6-fold higher than the 3.392- and 4.279-kb promoters, which did not significantly differ. Transgenic bovine fibroblasts were transduced with lentivirus carrying the 5.335-kb promoter and used as donor cells for SCNT. Cloned transgenic embryo production yielded development rates of 28.4%, similar to previous reports on cloned non-transgenic embryos. The embryos were transferred to recipient cows (N = 21) and 2 births of cloned transgenic cattle were obtained. These results suggest combination of the lentiviral system and cloning may be a good strategy for production of transgenic cattle.


Assuntos
Animais Geneticamente Modificados , Cruzamento/métodos , Bovinos/genética , Clonagem de Organismos , Fator IX/biossíntese , Animais , Caseínas/genética , Mapeamento Cromossômico , Fragmentação do DNA , Embrião de Mamíferos/metabolismo , Células Epiteliais/metabolismo , Fator IX/genética , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Vetores Genéticos , Humanos , Lentivirus/genética , Técnicas de Transferência Nuclear , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Análise de Sequência de DNA
16.
Genet Mol Res ; 11(1): 775-89, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22576836

RESUMO

Hemophilia A is the most common X-linked bleeding disorder; it is caused by deficiency of coagulation factor VIII (FVIII). Replacement therapy with rFVIII produced from human cell line is a major goal for treating hemophilia patients. We prepared a full-length recombinant FVIII (FVIII-FL), using the pMFG-P140K retroviral vector. The IRES DNA fragment was cloned upstream to the P140K gene, providing a 9.34-kb bicistronic vector. FVIII-FL cDNA was then cloned upstream to IRES, resulting in a 16.6-kb construct. In parallel, an eGFP control vector was generated, resulting in a 10.1- kb construct. The 293T cells were transfected with these constructs, generating the 293T-FVIII-FL/P140K and 293T-eGFP/P140K cell lines. In 293T-FVIII-FL/P140K cells, FVIII and P140K mRNAs levels were 4,410 (±931.7)- and 295,400 (±75,769)-fold higher than in virgin cells. In 293T-eGFP/P140K cells, the eGFP and P140K mRNAs levels were 1,501,000 (±493,700)- and 308,000 (±139,300)-fold higher than in virgin cells. The amount of FVIII-FL was 0.2 IU/mL and 45 ng/mL FVIII cells or 4.4 IU/µg protein. These data demonstrate the efficacy of the bicistronic retroviral vector expressing FVIII-FL and MGMT(P140K), showing that it could be used for producing the FVIII-FL protein in a human cell line.


Assuntos
Fator VIII/biossíntese , Vetores Genéticos , Retroviridae/genética , Fator VIII/genética , Ordem dos Genes , Células HEK293 , Humanos
17.
Tissue Antigens ; 80(2): 143-50, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22587568

RESUMO

Interleukin-18 (IL-18) and interferon-gamma (IFN-γ) exert important functions in both innate and adaptive immune responses against intracellular pathogens and viruses. Previous studies suggested that host genetic factors, including cytokines gene polymorphisms, could be involved in the pathogenesis of human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Thus, we analyzed -137C/G and -607A/C of the IL-18 promoter and +874T/A of the IFN-γ in DNA samples from 98 HTLV-1-infected individuals exhibiting or not clinical symptoms and 150 healthy control individuals. The IL-18 promoter -607CC genotype was significantly lower in HTLV-1 asymptomatic carriers (HAC) and HTLV-1-infected individuals (HAC + HAM/TSP) than healthy control group. In contrast, the -607AC genotype was significantly higher in HAC and HTLV-1-infected individuals group compared to the healthy control group. The -137G/-607A IL-18 haplotype was higher in infected group than healthy control group, and the -137C/-607C IL-18 haplotype was increased in the healthy control group compared to the others. Finally, the IFN-γ polymorphism analysis showed that the HTLV-1-infected individuals with +874AT genotype presented higher proviral load than +874AA genotype. These data indicate that the IL-18-607AC genotype and -137G/-607A haplotype could be a risk factor for HTLV-1 infection, whereas the protective effect could be conferred by -607CC genotype and -137C/-607C haplotype. Also, the IFN-γ could be implicated on the proviral load levels.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/imunologia , Interferon gama/genética , Interleucina-18/genética , Paraparesia Espástica Tropical/genética , Provírus , Adolescente , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Suscetibilidade a Doenças , Frequência do Gene , Haplótipos , Humanos , Interferon gama/imunologia , Interleucina-18/imunologia , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/virologia , Polimorfismo Genético , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Carga Viral
18.
Clin Exp Immunol ; 168(3): 291-302, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22519592

RESUMO

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by T cell-mediated destruction of pancreatic ß cells, resulting in insulin deficiency and hyperglycaemia. Recent studies have described that apoptosis impairment during central and peripheral tolerance is involved in T1D pathogenesis. In this study, the apoptosis-related gene expression in T1D patients was evaluated before and after treatment with high-dose immunosuppression followed by autologous haematopoietic stem cell transplantation (HDI-AHSCT). We also correlated gene expression results with clinical response to HDI-AHSCT. We observed a decreased expression of bad, bax and fasL pro-apoptotic genes and an increased expression of a1, bcl-x(L) and cIAP-2 anti-apoptotic genes in patients' peripheral blood mononuclear cells (PBMCs) compared to controls. After HDI-AHSCT, we found an up-regulation of fas and fasL and a down-regulation of anti-apoptotic bcl-x(L) genes expression in post-HDI-AHSCT periods compared to pre-transplantation. Additionally, the levels of bad, bax, bok, fasL, bcl-x(L) and cIAP-1 genes expression were found similar to controls 2 years after HDI-AHSCT. Furthermore, over-expression of pro-apoptotic noxa at 540 days post-HDI-AHSCT correlated positively with insulin-free patients and conversely with glutamic acid decarboxylase autoantibodies (GAD65) autoantibody levels. Taken together, the results suggest that apoptosis-related genes deregulation in patients' PBMCs might be involved in breakdown of immune tolerance and consequently contribute to T1D pathogenesis. Furthermore, HDI-AHSCT modulated the expression of some apoptotic genes towards the levels similar to controls. Possibly, the expression of these apoptotic molecules could be applied as biomarkers of clinical remission of T1D patients treated with HDI-AHSCT therapy.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/cirurgia , Proteína Ligante Fas/genética , Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Tolerância Imunológica/genética , Leucócitos Mononucleares/efeitos dos fármacos , Receptor fas/genética , Adolescente , Adulto , Apoptose/genética , Autoanticorpos/metabolismo , Regulação para Baixo , Feminino , Seguimentos , Glutamato Descarboxilase/imunologia , Humanos , Imunossupressores/administração & dosagem , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transplante Autólogo , Regulação para Cima , Adulto Jovem , Proteína bcl-X/genética , Proteína bcl-X/imunologia , Proteína bcl-X/metabolismo
19.
Braz. j. med. biol. res ; 45(2): 104-112, Feb. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-614579

RESUMO

Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.


Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Doadores de Sangue , Infecções por HIV/virologia , HIV-1 , Sequência de Bases , Western Blotting , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática , Genes env/genética , Genes gag/genética , Genes pol/genética , Infecções por HIV/epidemiologia , HIV-1 , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase
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