RESUMO
Recent studies have highlighted the pathogenic roles of IL-17-producing CD8+ T cells (T-cytotoxic 17 [Tc17]) in psoriasis. However, the underlying mechanisms of Tc17 induction remain unclear. In this study, we focused on the pathogenic subsets of Th17 and their mechanism of promotion of Tc17 responses. We determined that the pathogenic Th17-enriched fraction expressed melanoma cell adhesion molecule (MCAM) and CCR6, but not CD161, because this subset produced IL-17A abundantly and the presence of these cells in the peripheral blood of patients has been correlated with the severity of psoriasis. Intriguingly, the serial analysis of gene expression revealed that CCR6+MCAM+CD161-CD4+ T cells displayed the gene profile for adaptive immune responses, including CD83, which is an activator for CD8+ T cells. Coculture assay with or without intercellular contact between CD4+ and CD8+ T cells showed that CCR6+MCAM+CD161-CD4+ T cells induced the proliferation of CD8+ T cells in a CD83-dependent manner. However, the production of IL-17A by CD8+ T cells required exogenous IL-17A, suggesting that intercellular contact via CD83 and the production of IL-17A from activated CD4+ T cells elicit Tc17 responses. Intriguingly, the CD83 expression was enhanced in the presence of IL-15, and CD83+ cells stimulated with IL-1ß, IL-23, IL-15, and IL-15Rα did not express FOXP3. Furthermore, CCR6+MCAM+CD161-CD4+ T cells expressing CD83 were increased in the peripheral blood of patients, and the CD83+ Th17-type cells accumulated in the lesional skin of psoriasis. In conclusion, pathogenic MCAM+CD161- Th17 cells may be involved in the Tc17 responses via IL-17A and CD83 in psoriasis.
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The crystal structures and electron density distributions (EDDs) of Ca-deficient Sc-doped CaTiO3 fast oxide-ion conductors, Ca0.97(Ti0.97Sc0.03)O3-δ (CTS3) and Ca0.96(Ti0.9Sc0.1)O3-δ (CTS10), were investigated in the temperature range of 298-1173 K in N2 to analyze the effect of composition on the perovskite structure and oxide-ion transport mechanism. CTS3 and CTS10 exhibited orthorhombic Pnma symmetry in temperature ranges of 298-1173 K and 973-1173 K, respectively, with CTS10 exhibiting lower symmetry and reduction in oxide-ion conductivity below 973 K. The EDDs of CTS3 and CTS10 at 1173 K indicated unique chemical bonds and conduction paths. CTS3 and CTS10 showed covalent bonds between (Ti,Sc) and O1 (or O2) sites. CTS3, with a lower oxide-ion conductivity than that of CTS10, exhibited pseudo-one-dimensional (1D) zig-zag curved conduction paths for oxide-ions along the a-axis, unlike previously reported curved migration paths along the b-axis in CaTiO3, and chemical bonds between Ca and O1 sites, indicating oxide-ion conduction suppression. In CTS10, additional conduction paths were observed along the a-axis, forming three-dimensional (3D) zig-zag curved conduction paths in the ac-plane and along the b-axis, with the weakening of the chemical bonds between the Ca and O1 sites. The oxide-ion conductivity and mobile oxide-ion concentration of CTS10 were 3.6 and 2.0 times those of CTS3, respectively, at 1173 K; the higher oxide-ion conductivity of CTS10 could be attributed to an increase in the mobile oxide-ion concentration and mobility with a 1D to 3D change in the conduction paths and a weakening of chemical bonds between the Ca and O1 sites.
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Pituitary endocrine cells are supplied by Sox2-expressing stem/progenitor cells in the anterior lobe of the adult pituitary gland. These SOX2-positive cells are maintained in two types of microenvironments (niches): the marginal cell layer (MCL)-niche and the parenchymal-niche. Recently, we isolated dense SOX2-positive cell clusters from the parenchymal-niche by taking advantage of their resistance to protease treatment as parenchymal stem/progenitor cell (PS)-clusters. In the present study, by analyzing these isolated PS-clusters, we attempted to identify novel structural characteristics of pituitary stem/progenitor cell niches. Quantitative real-time PCR showed that tight junction-related genes were distinctly expressed in the isolated PS-clusters. Immunocytostaining showed that the tight junction molecules, ZO-1 and occludin, were localized in the apical membrane facing the pseudo-follicle-like structure of the isolated PS-clusters regardless of the expression of S100ß, which distinguishes the sub-population of SOX2-positive cells. Furthermore, immunohistochemistry of the pituitary glands of adult rats clearly demonstrated that ZO-1 and occludin were densely present in the parenchymal-niche encircling the pseudo-follicle, while they were observed in the apical membrane in the MCL-niche facing the residual lumen. Collectively, these tight junction-related proteins might be involved in the architecture and maintenance of the plasticity of pituitary stem/progenitor cell niches.
Assuntos
Proteínas de Junções Íntimas , Junções Íntimas , Animais , Ocludina/genética , Ocludina/metabolismo , Hipófise/metabolismo , Ratos , Nicho de Células-Tronco , Células-Tronco , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismoRESUMO
Patients with triple negative breast cancer (TNBC) is frequently complicated by bone metastasis, which deteriorates the life expectancy of this patient cohort. In order to develop a novel type of therapy for bone metastasis, we established 4T1.3 clone with a high capacity to metastasize to bone after orthotopic injection, from a murine TNBC cell line, 4T1.0. To elucidate the molecular mechanism underlying a high growth ability of 4T1.3 in a bone cavity, we searched for a novel candidate molecule with a focus on a transcription factor whose expression was selectively enhanced in a bone cavity. Comprehensive gene expression analysis detected enhanced Nfe2 mRNA expression in 4T1.3 grown in a bone cavity, compared with in vitro culture conditions. Moreover, Nfe2 gene transduction into 4T1.0 cells enhanced their capability to form intraosseous tumors. Moreover, Nfe2 shRNA treatment reduced tumor formation arising from intraosseous injection of 4T1.3 clone as well as another mouse TNBC-derived TS/A.3 clone with an augmented intraosseous tumor formation ability. Furthermore, NFE2 expression was associated with in vitro growth advantages of these TNBC cell lines under hypoxic condition, which mimics the bone microenvironment, as well as Wnt pathway activation. These observations suggest that NFE2 can potentially contribute to breast cancer cell survival in the bone microenvironment.
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Epstein-Barr virus-induced gene 3 (EBI3) is a subunit common to IL-27, IL-35, and IL-39. Here, we explore an intracellular role of EBI3 that is independent of its function in cytokines. EBI3-deficient naive CD4+ T cells had reduced IFN-γ production and failed to induce T cell-dependent colitis in mice. Similarly reduced IFN-γ production was observed in vitro in EBI3-deficient CD4+ T cells differentiated under pathogenic Th17 polarizing conditions with IL-23. This is because the induction of expression of one of the IL-23 receptor (IL-23R) subunits, IL-23Rα, but not another IL-23R subunit, IL-12Rß1, was selectively decreased at the protein level, but not the mRNA level. EBI3 augmented IL-23Rα expression via binding to the chaperone molecule calnexin and to IL-23Rα in a peptide-dependent manner, but not a glycan-dependent manner. Indeed, EBI3 failed to augment IL-23Rα expression in the absence of endogenous calnexin. Moreover, EBI3 poorly augmented the expression of G149R, an IL-23Rα variant that protects against the development of human colitis, because binding of EBI3 to the variant was reduced. Taken together with the result that EBI3 expression is inducible in T cells, the present results suggest that EBI3 plays a critical role in augmenting IL-23Rα protein expression via calnexin under inflammatory conditions.
Assuntos
Calnexina/imunologia , Regulação da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Menor/imunologia , Receptores de Citocinas/imunologia , Receptores de Interleucina/imunologia , Linfócitos T/imunologia , Substituição de Aminoácidos , Animais , Calnexina/genética , Camundongos , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/genética , Mutação de Sentido Incorreto , Receptores de Citocinas/genética , Receptores de Interleucina/genéticaRESUMO
Pituitary endocrine cells are supplied by Sox2-expressing stem/progenitor cells in the anterior lobe of the adult pituitary. In relation to their microenvironment ("niche"), SOX2-positive cells exist in two types of niches; the marginal cell layer-niche and the parenchymal-niche. Recently, we isolated dense stem/progenitor cell clusters from the parenchymal-niche as parenchymal stem/progenitor cell (PS)-clusters. We classified these PS-clusters into three subtypes based on differences in S100ß-expression (S100ß-positive, -negative, and -mixed type), and reported that S100ß-positive PS-clusters exhibited the capacity for differentiation into endocrine cells under 3-dimensional cultivation system. In the present study, we further characterized S100ß-positive PS-clusters using an in vitro 2-dimensional cultivation system. The results demonstrated that S100ß-positive PS-clusters in the 2-dimensional cultivation system proliferated more actively than S100ß-negative clusters. Moreover, in 2-dimensional cultivation conditions, S100ß-positive PS-clusters showed differentiation capacity into non-endocrine cells (Myogenin-, αSMA-, NG2-, or SOX17-positive cells) but not into endocrine cells, whereas S100ß-negative PS-clusters did not. Collectively, PS-clusters were heterogeneous, exhibiting different proliferation and differentiation properties based on the difference in S100ß-expression. Specifically, a part of SOX2-positive cells in the parenchymal-niche had capacities for differentiation into non-endocrine cells, and S100ß-positive PS-clusters may be in more progressive stages toward differentiation than S100ß-negative clusters.
Assuntos
Células-Tronco Adultas/citologia , Técnicas de Cultura de Células/métodos , Adeno-Hipófise/citologia , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Células-Tronco Adultas/metabolismo , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Plasticidade Celular , Proliferação de Células , Células Cultivadas , Células Endócrinas/citologia , Células Endócrinas/metabolismo , Adeno-Hipófise/metabolismo , Ratos , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Fatores de Transcrição SOXB1/metabolismo , Nicho de Células-TroncoRESUMO
Depletion of CD4+ cells using an anti-CD4 monoclonal antibody (anti-CD4 mAb) induces the expansion of tumor-reactive CD8+ T cells and strong antitumor effects in several murine tumor models. However, it is not known whether the anti-CD4 mAb treatment activates a particular or a broad spectrum of tumor-reactive CD8+ T cell clones. To investigate the changes in the TCR repertoire induced by the anti-CD4 mAb treatment, we performed unbiased high-throughput TCR sequencing in a B16F10 mouse subcutaneous melanoma model. By Inter-Organ Clone Tracking analysis, we demonstrated that anti-CD4 mAb treatment increased the diversity and combined frequency of CD8+ T cell clones that overlapped among the tumor, draining lymph node (dLN), and peripheral blood repertoires. Interestingly, the anti-CD4 mAb treatment-induced expansion of overlapping clones occurred mainly in the dLN rather than in the tumor. Overall, the Inter-Organ Clone Tracking analysis revealed that anti-CD4 mAb treatment enhances the mobilization of a wide variety of tumor-reactive CD8+ T cell clones into the Cancer-Immunity Cycle and thus induces a robust antitumor immune response in mice.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Evolução Clonal/imunologia , Ativação Linfocitária/imunologia , Neoplasias/imunologia , Neoplasias/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos Imunológicos/imunologia , Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Evolução Clonal/genética , Modelos Animais de Doenças , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Melanoma Experimental , Camundongos , Camundongos Transgênicos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/genética , Resultado do TratamentoRESUMO
There has been a strong demand in Japan and East Asia for L-glutamic acid as a seasoning since monosodium glutamate was found to present umami taste in 1907. The discovery of glutamate fermentation by Corynebacterium glutamicum in 1956 enabled abundant and low-cost production of the amino acid, creating a large market. The discovery also prompted researchers to develop fermentative production processes for other L-amino acids, such as lysine. Currently, the amino acid fermentation industry is so huge that more than 5 million metric tons of amino acids are manufactured annually all over the world, and this number continues to grow. Research on amino acid fermentation fostered the notion and skills of metabolic engineering which has been applied for the production of other compounds from renewable resources. The discovery of glutamate fermentation has had revolutionary impacts on both the industry and science. In this chapter, the history and development of glutamate fermentation, including the very early stage of fermentation of other amino acids, are reviewed.
Assuntos
Aminoácidos/biossíntese , Fenômenos Fisiológicos Bacterianos , Produtos Biológicos/metabolismo , Reatores Biológicos/microbiologia , Fermentação/fisiologia , Melhoramento Genético/métodos , Aminoácidos/genética , Produtos Biológicos/síntese química , Descoberta de DrogasRESUMO
From a murine breast cancer cell line, 4T1, we established a subclone, 4T1.3, which consistently metastasizes to bone upon its injection into the mammary fat pad. 4T1.3 clone exhibited similar proliferation rate and migration capacity as the parental clone. However, the intra-bone injection of 4T1.3 clone caused larger tumors than that of the parental cells, accompanied with increases in fibroblast, but not osteoclast or osteoblast numbers. 4T1.3 clone displayed an enhanced expression of a chemokine, CCL4, but not its specific receptor, CCR5. CCL4 shRNA-transfection of 4T1.3 clone had few effects on its in vitro properties, but reduced the tumorigenicity arising from the intra-bone injection. Moreover, intra-bone injection of 4T1.3 clone caused smaller tumors in mice deficient in CCR5 or those receiving CCR5 antagonist than in wild-type mice. The reduced tumor formation was associated with attenuated accumulation of CCR5-positive fibroblasts expressing connective tissue growth factor (CTGF)/CCN2. Tumor cell-derived CCL4 could induce fibroblasts to express CTGF/CCN2, which could support 4T1.3 clone proliferation under hypoxic culture conditions. Thus, the CCL4-CCR5 axis can contribute to breast cancer metastasis to bone by mediating the interaction between cancer cells and fibroblasts in bone cavity.
Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Movimento Celular , Quimiocina CCL4/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Comunicação Parácrina , Receptores CCR5/metabolismo , Animais , Anoikis , Neoplasias Ósseas/secundário , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CCL4/genética , Colágeno Tipo I/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Feminino , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Interferência de RNA , Receptores CCR5/deficiência , Receptores CCR5/genética , Transdução de Sinais , Fatores de Tempo , Transfecção , Carga Tumoral , Hipóxia TumoralRESUMO
Understanding cell-to-cell variability in cytosine methylation is essential for understanding cellular perturbation and its molecular machinery. However, conventional methylation studies have focused on the differences in the average levels between cell types while overlooking methylation heterogeneity within cell types. Little information has been uncovered using recent single-cell methods because of either technical limitations or the great labor required to process many single cells. Here, we report the highly efficient detection of cell-to-cell DNA methylation variability in liver tissue, based on comparing the methylation status of adjacent CpG sites on long sequencing reads. This method provides abundant methylation linkage information and enables genome-wide estimation of cell-to-cell variability. We observed repressed methylation variability in hypomethylated regions compared with the variability in hypomethylated regions across the genome, which we confirmed using public human sperm data. A gradual change in methylation status at the boundaries of hypomethylated regions was observed for the first time. This approach allows the concise, comprehensive assessment of cell-to-cell DNA methylation variability.
Assuntos
Ilhas de CpG , Metilação de DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , HumanosRESUMO
BACKGROUND: Transcription start sites (TSSs) with pronounced and phased nucleosome arrays downstream and nucleosome-depleted regions upstream of TSSs are observed in various species. RESULTS: We have characterized sequence variation and expression properties of this set of TSSs (which we call "Nucleocyclic TSSs") using germline and somatic cells of three medaka (Oryzias latipes) inbred isolates from different locations. We found nucleocyclic TSSs in medaka to be associated with higher gene expression and characterized by a clear boundary in sequence composition with potentially-nucleosome-destabilizing A/T-enrichment upstream (p < 10(-60)) and nucleosome- accommodating C/G-enrichment downstream (p < 10(-40)) that was highly conserved from an ancestor. A substantial genetic distance between the strains facilitated the in-depth analysis of patterns of fixed mutations, revealing a localization-specific equilibrium between the rates of distinct mutation categories that would serve to maintain the conserved sequence anisotropy around TSSs. Downstream of nucleocyclic TSSs, C to T, T to C, and other mutation rates on the sense strand increased around first nucleosome dyads and decreased around first linkers, which contrasted with genomewide mutational patterns around nucleosomes (p < 5 %). C to T rates are higher than G to A rates around nucleosome associated with germline nucleocyclic TSS sites (p < 5 %), potentially due to the asymmetric effect of transcription-coupled repair. CONCLUSIONS: Our results demonstrate an atypical evolutionary process surrounding nucleocyclic TSSs.
Assuntos
Endogamia , Nucleossomos/genética , Oryzias/genética , Animais , Evolução Molecular , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Sítio de Iniciação de TranscriçãoRESUMO
BACKGROUND: Renal coloboma syndrome (RCS) is characterized by renal anomalies and optic nerve colobomas. PAX2 mutations contribute to RCS. However, approximately half of the patients with RCS have no mutation in PAX2 gene. METHODS: To investigate the incidence and effects of mutations of PAX2 and 25 candidate genes, patient genes were screened using next-generation sequence analysis, and candidate mutations were confirmed using Sanger sequencing. The correlation between mutations and clinical manifestation was evaluated. RESULT: Thirty patients, including 26 patients (two families of five and two, 19 sporadic cases) with RCS, and 4 optic nerve coloboma only control cases were evaluated in the present study. Six PAX2 mutations in 21 probands [28%; two in family cohorts (n = 5 and n = 2) and in 4 out of 19 patients with sporadic disease] including four novel mutations were confirmed using Sanger sequencing. Moreover, four other sequence variants (CHD7, SALL4, KIF26B, and SIX4) were also confirmed, including a potentially pathogenic novel KIF26B mutation. Kidney function and proteinuria were more severe in patients with PAX2 mutations than in those without the mutation. Moreover, the coloboma score was significantly higher in patients with PAX2 gene mutations. Three out of five patients with PAX2 mutations had focal segmental glomerulosclerosis (FSGS) diagnosed from kidney biopsies. CONCLUSION: The results of this study identify several new mutations of PAX2, and sequence variants in four additional genes, including a novel potentially pathogenic mutation in KIF26B, which may play a role in the pathogenesis of RCS.
Assuntos
Coloboma/genética , Coloboma/patologia , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação/genética , Fator de Transcrição PAX2/genética , Insuficiência Renal/genética , Insuficiência Renal/patologia , Refluxo Vesicoureteral/genética , Refluxo Vesicoureteral/patologia , Sequência de Aminoácidos , Éxons/genética , Família , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Rim/patologia , Masculino , Dados de Sequência Molecular , Nervo Óptico/anormalidades , Fator de Transcrição PAX2/química , LinhagemRESUMO
Pulmonary fibrosis (PF) is an intractable disorder with a poor prognosis. Lung macrophages have been reported to regulate both progression and remission of bleomycin-induced diffuse PF. However, it remains unclear how macrophages contribute to silica-induced progressive nodular PF and the associated tissue cell responses in vivo. We found that lack of monocyte-derived macrophages results in the formation of diffuse PF after silica instillation. We found that the proportion and the number of monocyte-derived macrophages were persistently higher in silica-induced progressive PF compared with bleomycin-induced PF. Surprisingly, in Ccr2(-/-) mice, in which monocyte-derived macrophage infiltration is impaired, silica administration induced diffuse PF with loose nodule formation and greater activation of tissue cells. In the diffuse lesions, the distribution of epithelial cells, distribution of myofibroblasts, and architecture of the basement membrane were disrupted. Consistent with the development of diffuse lesions, genes that were differentially expressed in CD45(-) tissue cells from the lung of wild-type and Ccr2(-/-) mice were highly enriched in human diffuse, progressive PF. In gene ontology network analyses, many of these genes were associated with tissue remodeling and included genes not previously associated with PF, such as Mmp14, Thbs2, and Fgfr4. Overall, these results indicate that monocyte-derived macrophages prevent transition from nodular to diffuse silica-induced PF, potentially by regulating tissue cell responses.
Assuntos
Macrófagos Alveolares/patologia , Fibrose Pulmonar/patologia , Receptores CCR2/metabolismo , Animais , Bleomicina/efeitos adversos , Modelos Animais de Doenças , Células Epiteliais/patologia , Perfilação da Expressão Gênica , Humanos , Hidroxiprolina/análise , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Monócitos , Análise de Sequência com Séries de Oligonucleotídeos , Fibrose Pulmonar/induzido quimicamente , Receptores CCR2/genética , Dióxido de Silício/efeitos adversosRESUMO
Lymph node (LN) stromal cells (LNSCs) form the functional structure of LNs and play an important role in lymphocyte survival and the maintenance of immune tolerance. Despite their broad spectrum of function, little is known about LNSC responses during microbial infection. In this study, we demonstrate that LNSC subsets display distinct kinetics following vaccinia virus infection. In particular, compared with the expansion of other LNSC subsets and the total LN cell population, the expansion of fibroblastic reticular cells (FRCs) was delayed and sustained by noncirculating progenitor cells. Notably, newly generated FRCs were preferentially located in perivascular areas. Viral clearance in reactive LNs preceded the onset of FRC expansion, raising the possibility that viral infection in LNs may have a negative impact on the differentiation of FRCs. We also found that MHC class II expression was upregulated in all LNSC subsets until day 10 postinfection. Genetic ablation of radioresistant stromal cell-mediated Ag presentation resulted in slower contraction of Ag-specific CD4(+) T cells. We propose that activated LNSCs acquire enhanced Ag-presentation capacity, serving as an extrinsic brake system for CD4(+) T cell responses. Disrupted function and homeostasis of LNSCs may contribute to immune deregulation in the context of chronic viral infection, autoimmunity, and graft-versus-host disease.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfonodos/citologia , Células Estromais/imunologia , Vaccinia virus/imunologia , Transferência Adotiva , Animais , Apresentação de Antígeno/imunologia , Antígeno B7-1/biossíntese , Linfócitos T CD4-Positivos/transplante , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe II/biossíntese , Receptores de Hialuronatos/biossíntese , Tolerância Imunológica , Integrina beta1/biossíntese , Linfonodos/virologia , Receptor beta de Linfotoxina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Parabiose , Receptores do Fator de Crescimento Derivado de Plaquetas/biossíntese , Transdução de Sinais/imunologia , Vacínia/imunologia , Molécula 1 de Adesão de Célula Vascular/biossínteseRESUMO
Dendritic cell (DC) subsets in the skin and draining lymph nodes (LNs) are likely to elicit distinct immune response types. In skin and skin-draining LNs, a dermal DC subset expressing macrophage galactose-type C-type lectin 2 (MGL2/CD301b) was found distinct from migratory Langerhans cells (LCs) or CD103(+) dermal DCs (dDCs). Lower expression levels of Th1-promoting and/or cross-presentation-related molecules were suggested by the transcriptome analysis and verified by the quantitative real-time PCR analysis in MGL2(+) dDCs than in CD103(+) dDCs. Transfer of MGL2(+) dDCs but not CD103(+) dDCs from FITC-sensitized mice induced a Th2-type immune response in vivo in a model of contact hypersensitivity. Targeting MGL2(+) dDCs with a rat monoclonal antibody against MGL2 efficiently induced a humoral immune response with Th2-type properties, as determined by the antibody subclass. We propose that the properties of MGL2(+) dDCs, are complementary to those of CD103(+) dDCs and skew the immune response toward a Th2-type response.
Assuntos
Células Dendríticas/imunologia , Células Th2/imunologia , Animais , Antígenos CD/imunologia , Dermatite de Contato/imunologia , Feminino , Cadeias alfa de Integrinas/imunologia , Lectinas Tipo C/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ratos , Pele/citologia , Pele/imunologiaRESUMO
Pulmonary fibrosis is characterized by accumulation of activated fibroblasts that produce excessive amounts of extracellular matrix components such as collagen type I. However, the dynamics and activation signatures of fibroblasts during fibrogenesis remain poorly understood, especially in vivo. We examined changes in lung tissue cell populations and in the phenotype of activated fibroblasts after acute injury in a model of bleomycin-induced pulmonary fibrosis. Despite clustering of collagen type I-producing fibroblasts in fibrotic regions, flow cytometry-based quantitative analysis of whole lungs revealed that the number of fibroblasts in the lungs remained constant. At the peak of inflammation, fibroblast proliferation and apoptosis were both increased, suggesting that the clustering was not merely a result of proliferation, but also of fibroblast migration from nearby alveolar walls. Parabiosis experiments demonstrated that fibroblasts were not supplied from the circulation. Comprehensive gene expression analysis of freshly isolated fibroblasts revealed a detailed activation signature associated with fibrogenesis, including changes in genes responsible for migration and extracellular matrix construction. The Spp1 gene, which encodes osteopontin, was highly up-regulated and was an identifying characteristic of activated fibroblasts present at the sites of remodeling. Osteopontin may serve as a useful marker of profibrotic fibroblasts. These results provide insights into the cellular and molecular mechanisms underlying pulmonary fibrosis and provide a foundation for development of specific antifibrotic therapies.
Assuntos
Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Animais , Apoptose , Biomarcadores/metabolismo , Bleomicina , Células da Medula Óssea/patologia , Proliferação de Células , Colágeno Tipo I/metabolismo , Perfilação da Expressão Gênica , Ontologia Genética , Proteínas de Fluorescência Verde/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Osteopontina/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Regulação para Cima/genéticaRESUMO
More than half of Caenorhabditis elegans pre-mRNAs lose their original 5' ends in a process termed "trans-splicing" in which the RNA extending from the transcription start site (TSS) to the site of trans-splicing of the primary transcript, termed the "outron," is replaced with a 22-nt spliced leader. This complicates the mapping of TSSs, leading to a lack of available TSS mapping data for these genes. We used growth at low temperature and nuclear isolation to enrich for transcripts still containing outrons, applying a modified SAGE capture procedure and high-throughput sequencing to characterize 5' termini in this transcript population. We report from this data both a landscape of 5'-end utilization for C. elegans and a representative collection of TSSs for 7351 trans-spliced genes. TSS distributions for individual genes were often dispersed, with a greater average number of TSSs for trans-spliced genes, suggesting that trans-splicing may remove selective pressure for a single TSS. Upstream of newly defined TSSs, we observed well-known motifs (including TATAA-box and SP1) as well as novel motifs. Several of these motifs showed association with tissue-specific expression and/or conservation among six worm species. Comparing TSS features between trans-spliced and non-trans-spliced genes, we found stronger signals among outron TSSs for preferentially positioning of flanking nucleosomes and for downstream Pol II enrichment. Our data provide an enabling resource for both experimental and theoretical analysis of gene structure and function in C. elegans.
Assuntos
Caenorhabditis elegans/genética , Genes de Helmintos , Sítio de Iniciação de Transcrição , Regiões 5' não Traduzidas , Animais , Sequência de Bases , Sequência Conservada , Regulação da Expressão Gênica , Anotação de Sequência Molecular , Especificidade de Órgãos , Regiões Promotoras Genéticas , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Trans-SplicingRESUMO
Memory CD4(+) T cells are central regulators of both humoral and cellular immune responses. T cell differentiation results in specific changes in chromatin structure and DNA methylation of cytokine genes. Although the methylation status of a limited number of gene loci in T cells has been examined, the genome-wide DNA methylation status of memory CD4(+) T cells remains unexplored. To further elucidate the molecular signature of memory T cells, we conducted methylome and transcriptome analyses of memory CD4(+) T cells generated using T cells from TCR-transgenic mice. The resulting genome-wide DNA methylation profile revealed 1144 differentially methylated regions (DMRs) across the murine genome during the process of T cell differentiation, 552 of which were associated with gene loci. Interestingly, the majority of these DMRs were located in introns. These DMRs included genes such as CXCR6, Tbox21, Chsy1, and Cish, which are associated with cytokine production, homing to bone marrow, and immune responses. Methylation changes in memory T cells exposed to specific Ag appeared to regulate enhancer activity rather than promoter activity of immunologically relevant genes. In addition, methylation profiles differed between memory T cell subsets, demonstrating a link between T cell methylation status and T cell differentiation. By comparing DMRs between naive and Ag-specific memory T cells, this study provides new insights into the functional status of memory T cells.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Metilação de DNA/genética , Epitopos de Linfócito T/metabolismo , Memória Imunológica/genética , Animais , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Epitopos de Linfócito T/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Transgênicos , TranscriptomaRESUMO
A 38-year-old woman presented for evaluation of a firm mass (measuring 20 × 20 mm) in the upper outer quadrant of her left breast. On the basis of the clinical and radiologic findings, we diagnosed a benign breast tumor and scheduled removal by a hand-held vacuum-assisted biopsy device (VABD) under ultrasonographic guidance. Because the first specimen removed from the tumor was white, flaky, and waxy material, we strongly suspected that the lesion was an epidermal cyst. We continued VABD treatment until the tumor was invisible on real-time ultrasonography. Histologic examination demonstrated that the tumor was composed of mature stratified squamous epithelium and laminated layers of keratin, findings consistent with a diagnosis of epidermal cyst. These cysts rarely occur in the breast and are sometimes difficult to distinguish from breast cancer. To our knowledge, this is the first report of an epidermal cyst treated by VABD.
Assuntos
Cisto Mamário/cirurgia , Cisto Epidérmico/cirurgia , Adulto , Cisto Mamário/diagnóstico por imagem , Cisto Mamário/patologia , Cisto Epidérmico/diagnóstico por imagem , Cisto Epidérmico/patologia , Feminino , Humanos , Biópsia Guiada por Imagem , Ultrassonografia de Intervenção , Ultrassonografia Mamária , VácuoRESUMO
Zinc (Zn) deficiency in utero has been shown to cause a variety of disease states in children in developing countries, which prompted us to formulate the hypothesis that fetal epigenetic alterations are induced by zinc deficiency in utero. Focusing on metallothionein (MT), a protein that contributes to Zn transport and homeostasis, we studied whether and how the prenatal Zn status affects gene expression. Pregnant mice were fed low-Zn (IU-LZ, 5.0 µg Zn/g) or control (IU-CZ, 35 µg Zn/g) diet ad libitum from gestation day 8 until delivery, with a regular diet thereafter. Bisulfite genomic sequencing for DNA methylation and chromatin immunoprecipitation assay for histone modifications were performed on the MT2 promoter region. We found that 5-week-old IU-LZ mice administered cadmium (Cd) (5.0 mg/kg b.w.) have an elevated abundance of MT2 mRNA compared with IU-CZ mice. Alteration of histone modifications in the MT2 promoter region having metal responsive elements (MREs) was observed in 1-day-old and 5-week-old IU-LZ mice compared with IU-CZ mice. In addition, prolongation of MTF1 binding to the MT2 promoter region in 5-week-old IU-LZ mice upon Cd exposure is considered to contribute to the enhanced MT2 induction. In conclusion, we found for the first time that Zn deficiency in utero induces fetal epigenetic alterations and that these changes are being stored as an epigenetic memory until adulthood.