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1.
Glycobiology ; 31(10): 1401-1414, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34192331

RESUMO

Immunoglobulin G (IgG) has a conserved N-glycosylation site at Asn297 in the fragment crystallizable (Fc) region. Previous studies have shown that N-glycosylation of this site is a critical mediator of the antibody's effector functions, such as antibody-dependent cellular cytotoxicity. While the N-glycan structures attached to the IgG-Fc region are generally heterogenous, IgGs engineered to be homogenously glycosylated with functional N-glycans may improve the efficacy of antibodies. The major glycoforms of the N-glycans on the IgG-Fc region are bi-antennary complex-type N-glycans, while multibranched complex-type N-glycans are not typically found. However, IgGs with tri-antennary complex-type N-glycans have been generated using the N-glycan remodeling technique, suggesting that more branched N-glycans might be artificially attached. At present, little is known about the properties of these IgGs. In this study, IgGs with multibranched N-glycans on the Fc region were prepared by using a combination of the glycosynthase/oxazoline substrate-based N-glycan remodeling technique and successive reactions with glycosyltransferases. Among the IgGs produced by these methods, the largest N-glycan attached was a bisecting N-acetylglucosamine containing a sialylated penta-antennary structure. Concerning the Fc-mediated effector functions, the majority of IgGs with tri- and tetra-antennary N-glycans on their Fc region showed properties similar to IgGs with ordinary bi-antennary N-glycans.


Assuntos
Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Polissacarídeos/imunologia , Receptor ErbB-2/imunologia , Acetilglucosamina/imunologia , Humanos
2.
Acta Histochem Cytochem ; 51(6): 185-190, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30647493

RESUMO

We previously reported that the terminal differentiation of odontoblasts was inhibited in Runx2 transgenic {Tg(Col1a1-Runx2)} mice under the control of the 2.3-kb Col1a1 promoter. Odontoblasts in Tg(Col1a1-Runx2) mice lose their characteristic long cellular processes, and show marked reductions in the protein levels of markers for odontoblasts, such as dentin sialophosphoprotein, nestin, and microtubule-associated protein tau (Mapt). We herein demonstrated that collapsin response mediator protein 1 (CRMP1), a neuronal phosphoprotein that participates in various aspects of neuronal development, was specifically expressed in the differentiated odontoblasts of wild-type, but not Tg(Col1a1-Runx2) tooth germs by comparing expression profiles in wild-type and Tg(Col1a1-Runx2) mouse molars using microarray and immunohistochemical analyses. CRMP1 expression was detected at a slightly later differentiation stage in odontoblasts than type 1 collagen, nestin, and Mapt expression, which was observed from the onset of dentinogenesis. Among these proteins, CRMP1 was the most specifically localized in odontoblasts in the tooth germ. In erupted molars, odontoblast-specific CRMP1 expression decreased with age. These results indicate that CRMP1 is a novel marker protein for differentiated odontoblasts in mouse tooth germs, and suggest that CRMP1 participates in the morphogenesis of functioning odontoblasts.

3.
Biosci Biotechnol Biochem ; 81(12): 2353-2359, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29090617

RESUMO

Recently, the absence of a core-fucose residue in the N-glycan has been implicated to be important for enhancing antibody-dependent cellular cytotoxicity (ADCC) activity of immunoglobulin G monoclonal antibodies (mAbs). Here, we first prepared anti-HER2 mAbs having two core-fucosylated N-glycan chains with the single G2F, G1aF, G1bF, or G0F structure, together with those having two N-glycan chains with a single non-core-fucosylated corresponding structure for comparison, and determined their biological activities. Dissociation constants of mAbs with core-fucosylated N-glycans bound to recombinant Fcγ-receptor type IIIa variant were 10 times higher than those with the non-core-fucosylated N-glycans, regardless of core glycan structures. mAbs with the core-fucosylated N-glycans had markedly reduced ADCC activities, while those with the non-core-fucosylated N-glycans had high activities. These results indicate that the presence of a core-fucose residue in the N-glycan suppresses the binding to the Fc-receptor and the induction of ADCC of anti-HER2 mAbs.


Assuntos
Fucose/química , Polissacarídeos/química , Polissacarídeos/metabolismo , Receptor ErbB-2/imunologia , Trastuzumab/imunologia , Trastuzumab/metabolismo , Animais , Citotoxicidade Celular Dependente de Anticorpos , Células CHO , Sequência de Carboidratos , Cricetinae , Cricetulus , Receptores de IgG/imunologia
4.
PLoS One ; 10(7): e0132848, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26200113

RESUMO

Many therapeutic antibodies have been developed, and IgG antibodies have been extensively generated in various cell expression systems. IgG antibodies contain N-glycans at the constant region of the heavy chain (Fc domain), and their N-glycosylation patterns differ during various processes or among cell expression systems. The Fc N-glycan can modulate the effector functions of IgG antibodies, such as antibody-dependent cellular cytotoxicity (ADCC) and complement dependent cytotoxicity (CDC). To control Fc N-glycans, we performed a rearrangement of Fc N-glycans from a heterogeneous N-glycosylation pattern to homogeneous N-glycans using chemoenzymatic approaches with two types of endo-ß-N-acetyl glucosaminidases (ENG'ases), one that works as a hydrolase to cleave all heterogeneous N-glycans, another that is used as a glycosynthase to generate homogeneous N-glycans. As starting materials, we used an anti-Her2 antibody produced in transgenic silkworm cocoon, which consists of non-fucosylated pauci-mannose type (Man2-3GlcNAc2), high-mannose type (Man4-9GlcNAc2), and complex type (Man3GlcNAc3-4) N-glycans. As a result of the cleavage of several ENG'ases (endoS, endoM, endoD, endoH, and endoLL), the heterogeneous glycans on antibodies were fully transformed into homogeneous-GlcNAc by a combination of endoS, endoD, and endoLL. Next, the desired N-glycans (M3; Man3GlcNAc1, G0; GlcNAc2Man3GlcNAc1, G2; Gal2GlcNAc2Man3GlcNAc1, A2; NeuAc2Gal2GlcNAc2Man3GlcNAc1) were transferred from the corresponding oxazolines to the GlcNAc residue on the intact anti-Her2 antibody with an ENG'ase mutant (endoS-D233Q), and the glycoengineered anti-Her2 antibody was obtained. The binding assay of anti-Her2 antibody with homogenous N-glycans with FcγRIIIa-V158 showed that the glycoform influenced the affinity for FcγRIIIa-V158. In addition, the ADCC assay for the glycoengineered anti-Her2 antibody (mAb-M3, mAb-G0, mAb-G2, and mAb-A2) was performed using SKBR-3 and BT-474 as target cells, and revealed that the glycoform influenced ADCC activity.


Assuntos
Anticorpos Monoclonais/metabolismo , Fragmentos Fc das Imunoglobulinas/metabolismo , Polissacarídeos/química , Trastuzumab/metabolismo , Acetilglucosaminidase/metabolismo , Anticorpos Monoclonais/química , Citotoxicidade Celular Dependente de Anticorpos , Glicosilação , Humanos , Trastuzumab/química
5.
Cell Tissue Res ; 361(2): 457-66, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25707508

RESUMO

Runx2 is an essential transcription factor for osteoblast and odontoblast differentiation and the terminal differentiation of chondrocytes. We have previously shown that the terminal differentiation of odontoblasts is inhibited in Runx2 transgenic {Tg(Col1a1-Runx2)} mice under the control of the 2.3-kb Col1a1 promoter, which directs the transgene expression to osteoblasts and odontoblasts. Odontoblasts show severe reductions in Dspp and nestin expression and lose their characteristic polarized morphology, including a long process extending to dentin, in Tg(Col1a1-Runx2) mice. We study the molecular mechanism of odontoblast morphogenesis by comparing gene expression in the molars of wild-type and Tg(Col1a1-Runx2) mice, focusing on cytoskeleton-related genes. Using microarray, we found that the gene expression of microtubule-associated protein tau (Mapt), a neuronal phosphoprotein with important roles in neuronal biology and microtubule dynamics and assembly, was high in wild-type molars but severely reduced in Tg(Col1a1-Runx2) molars. Immunohistochemical analysis revealed that Mapt was specifically expressed in terminally differentiated odontoblasts including their processes in wild-type molars but its expression was barely detectable in Tg(Col1a1-Runx2) molars. Double-staining of Mapt and Runx2 showed their reciprocal expression in odontoblasts. Mapt and tubulin co-localized in odontoblasts in wild-type molars. Immunoelectron microscopic analysis demonstrated Mapt lying around α-tubulin-positive filamentous structures in odontoblast processes. Thus, Mapt is a useful marker for terminally differentiated odontoblasts and might play an important role in odontoblast morphogenesis.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/genética , Regulação para Baixo , Odontoblastos/citologia , Proteínas tau/genética , Animais , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Camundongos Transgênicos , Odontoblastos/metabolismo , Odontoblastos/patologia , Odontogênese , Transcriptoma , Tubulina (Proteína)/análise , Proteínas tau/análise
6.
Anticancer Res ; 35(1): 555-62, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25550602

RESUMO

BACKGROUND/AIM: Treatment combining dendritic cells (DCs) pulsed with three types of major histocompatibility complex (MHC) class I and II (DC/WT1-I/II)-restricted Wilms' tumor 1 (WT1) peptides with chemotherapy may stabilize disease in pancreatic cancer patients. MATERIALS AND METHODS: Laboratory data from seven patients with pancreatic cancer who underwent combined DC/WT1-I/II vaccination and chemotherapy were analyzed. The DC phenotypes and plasma cytokine profiles were analyzed via flow cytometry. RESULTS: The post-treatment neutrophil to lymphocyte (N/L) ratio was a treatment-related prognostic factor for better survival. Moreover, the mean fluorescence intensities (MFIs) of human leukocyte antigen (HLA)-DR and cluster of differentiation (CD)83 on DCs were significantly increased after chemoimmunotherapy. Interestingly, interleukin (IL)-6 level in plasma was significantly increased after chemoimmunotherapy in non-super-responders. CONCLUSION: An increased N/L ratio, as well as HLA-DR and CD83 MFI levels may be prognostic markers of longer survival in patients with advanced pancreatic cancer who undergo chemoimmunotherapy.


Assuntos
Adenocarcinoma/terapia , Vacinas Anticâncer/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Neoplasias Pancreáticas/terapia , Proteínas WT1/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Vacinas Anticâncer/administração & dosagem , Células Cultivadas , Terapia Combinada , Citocinas/sangue , Células Dendríticas/imunologia , Células Dendríticas/transplante , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Fragmentos de Peptídeos/imunologia , Prognóstico , Resultado do Tratamento , Vacinação , Gencitabina
7.
J Biol Chem ; 289(38): 26584-26596, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25107907

RESUMO

Galnt3, UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 3, transfers N-acetyl-D-galactosamine to serine and threonine residues, initiating mucin type O-glycosylation of proteins. We searched the target genes of Runx2, which is an essential transcription factor for chondrocyte maturation, in chondrocytes and found that Galnt3 expression was up-regulated by Runx2 and severely reduced in Runx2(-/-) cartilaginous skeletons. To investigate the function of Galnt3 in chondrocytes, we generated Galnt3(-/-) mice and chondrocyte-specific Galnt3 transgenic mice under the control of the Col2a1 promoter-enhancer. Galnt3(-/-) mice showed a delay in endochondral ossification and shortened limbs at embryonic day 16.5, suggesting that Galnt3 is involved in chondrocyte maturation. Galnt3 transgenic mice presented dwarfism, the chondrocyte maturation was retarded, the cell cycle in chondrocytes was accelerated, premature chondrocyte apoptosis occurred, and the growth plates were disorganized. The binding of Vicia villosa agglutinin, which recognizes the Tn antigen (GalNAc-O-Ser/Thr), was drastically increased in chondrocytes, and aggrecan (Acan) was highly enriched with Tn antigen. However, safranin O staining, which recognizes glycosaminoglycans (GAGs), and Acan were severely reduced. Chondroitin sulfate was reduced in amount, but the elongation of chondroitin sulfate chains had not been severely disturbed in the isolated GAGs. These findings indicate that overexpression of Galnt3 in chondrocytes caused dwarfism due to the increase of mucin-type O-glycans and the reduction of GAGs, probably through competition with xylosyltransferases, which initiate GAG chains by attaching O-linked xylose to serine residues, suggesting a negative effect of Galnt family proteins on Acan deposition in addition to the positive effect of Galnt3 on chondrocyte maturation.


Assuntos
Condrócitos/metabolismo , Sulfatos de Condroitina/metabolismo , Nanismo/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Agrecanas/genética , Agrecanas/metabolismo , Animais , Apoptose , Cartilagem/metabolismo , Cartilagem/patologia , Proliferação de Células , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Expressão Gênica , Glicosilação , Lâmina de Crescimento/metabolismo , Lâmina de Crescimento/patologia , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , N-Acetilgalactosaminiltransferases/genética , Osteogênese , Polipeptídeo N-Acetilgalactosaminiltransferase
8.
Clin Cancer Res ; 20(16): 4228-39, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25056373

RESUMO

PURPOSE: We performed a phase I trial to investigate the safety, clinical responses, and Wilms' tumor 1 (WT1)-specific immune responses following treatment with dendritic cells (DC) pulsed with a mixture of three types of WT1 peptides, including both MHC class I and II-restricted epitopes, in combination with chemotherapy. EXPERIMENTAL DESIGN: Ten stage IV patients with pancreatic ductal adenocarcinoma (PDA) and 1 patient with intrahepatic cholangiocarcinoma (ICC) who were HLA-positive for A*02:01, A*02:06, A*24:02, DRB1*04:05, DRB1*08:03, DRB1*15:01, DRB1*15:02, DPB1*05:01, or DPB1*09:01 were enrolled. The patients received one course of gemcitabine followed by biweekly intradermal vaccinations with mature DCs pulsed with MHC class I (DC/WT1-I; 2 PDA and 1 ICC), II (DC/WT1-II; 1 PDA), or I/II-restricted WT1 peptides (DC/WT1-I/II; 7 PDA), and gemcitabine. RESULTS: The combination therapy was well tolerated. WT1-specific IFNγ-producing CD4(+) T cells were significantly increased following treatment with DC/WT1-I/II. WT1 peptide-specific delayed-type hypersensitivity (DTH) was detected in 4 of the 7 patients with PDA vaccinated with DC/WT1-I/II and in 0 of the 3 patients with PDA vaccinated with DC/WT1-I or DC/WT1-II. The WT1-specific DTH-positive patients showed significantly improved overall survival (OS) and progression-free survival (PFS) compared with the negative control patients. In particular, all 3 patients with PDA with strong DTH reactions had a median OS of 717 days. CONCLUSIONS: The activation of WT1-specific immune responses by DC/WT1-I/II combined with chemotherapy may be associated with disease stability in advanced pancreatic cancer.


Assuntos
Células Dendríticas/imunologia , Desoxicitidina/análogos & derivados , Epitopos/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Neoplasias Pancreáticas/terapia , Proteínas WT1/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adenocarcinoma/terapia , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias dos Ductos Biliares/imunologia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/secundário , Neoplasias dos Ductos Biliares/terapia , Ductos Biliares Intra-Hepáticos/imunologia , Biomarcadores Tumorais/análise , Linfócitos T CD8-Positivos/imunologia , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/secundário , Carcinoma Ductal Pancreático/terapia , Colangiocarcinoma/imunologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/secundário , Colangiocarcinoma/terapia , Terapia Combinada , Desoxicitidina/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Fragmentos de Peptídeos/imunologia , Prognóstico , Taxa de Sobrevida , Linfócitos T Citotóxicos/imunologia , Vacinação , Gencitabina
9.
Acta Histochem Cytochem ; 47(1): 19-25, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24761046

RESUMO

Angiopoietin-1 regulates vascular angiogenesis and stabilization, and is reported to promote bone formation by facilitating angiogenesis. To estimate the role of Ang1 in odontogenesis, we explored the distribution of Ang1 and the receptor, Tie2 in the mouse developing and mature first molar of the mandible. At embryonic day 18, when differentiation of odontoblasts begins, immunosignals for Ang1 were intensely detected in the basement membrane and the distal side, which faced the basement membrane of odontoblasts. In situ hybridization revealed that Ang1 was expressed in odontoblasts and ameloblasts facing the basement membrane. Tie2 was localized in the distal side of odontoblasts. After birth, Ang1 was detected in the predentin, whereas both Ang1 and Tie2 were colocalized in odontoblasts and odontoblast processes. These distributions were retained up to 8 weeks. In contrast to odontoblasts, ameloblasts, cementoblasts and osteoblasts expressed Ang1 but did not express Tie2. Colocalization of Ang1 and Tie2 in odontoblasts and selective expression of Tie2 in odontoblasts among cells responsible for calcified tissue formation suggested the involvement of autocrine signals of Ang1-Tie2 in dentinogenesis.

10.
J Bone Miner Res ; 29(9): 1960-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24692107

RESUMO

Runx2 is essential for osteoblast differentiation and chondrocyte maturation. The expression of Runx2 is the first requisite step for the lineage determination from mesenchymal stem cells to osteoblasts. Although the transcript from Runx2 distal promoter is majorly expressed in osteoblasts, the promoter failed to direct green fluorescent protein (GFP) expression to osteoblasts. To find the regulatory region, we generated GFP reporter mice driven by a bacterial artificial chromosome (BAC) of Runx2 locus, and succeeded in the reproduction of endogenous Runx2 expression. By serially deleting it, we identified a 343-bp enhancer, which directed GFP expression specifically to osteoblasts, about 30 kb upstream of the distal promoter. The sequence of the 343-bp enhancer was highly conserved among mouse, human, dog, horse, opossum, and chicken. Dlx5, Mef2c, Tcf7, Ctnnb1, Sp7, Smad1, and Sox6, which localized on the enhancer region in primary osteoblasts, synergistically upregulated the enhancer activity, whereas Msx2 downregulated the activity in mouse osteoblastic MC3T3-E1 cells. Msx2 was predominantly bound to the enhancer in mouse multipotent mesenchymal C3H10T1/2 cells, whereas Dlx5 was predominantly bound to the enhancer in MC3T3-E1 cells. Dlx5 and Mef2 directly bound to the enhancer, and the binding sites were required for the osteoblast-specific expression in mice, whereas the other factors bound to the enhancer by protein-protein interaction. The enhancer was characterized by the presence of the histone variant H2A.Z, the enrichment of histone H3 mono- and dimethylated at Lys4 and acetylated at Lys18 and Lys27, but the depletion of histone H3 trimethylated at Lys4 in primary osteoblasts. These findings indicated that the enhancer, which had typical histone modifications for enhancers, contains sufficient elements to direct Runx2 expression to osteoblasts, and that Dlx5 and Mef2, which formed an enhanceosome with Tcf7, Ctnnb1, Sp7, Smad1, and Sox6, play an essential role in the osteoblast-specific activation of the enhancer. © 2014 American Society for Bone and Mineral Research.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/genética , Elementos Facilitadores Genéticos/genética , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição MEF2/metabolismo , Osteoblastos/metabolismo , Animais , Pareamento de Bases/genética , Linhagem Celular , Imunoprecipitação da Cromatina , Cromossomos Artificiais Bacterianos/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Regulação da Expressão Gênica , Genes Reporter , Loci Gênicos , Proteínas de Fluorescência Verde/metabolismo , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Histonas/metabolismo , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Fatores de Transcrição SOX/metabolismo , Proteína Smad1/metabolismo , Fator de Transcrição Sp7 , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo
11.
Histochem Cell Biol ; 139(2): 339-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23052838

RESUMO

Galnt3 belongs to the GalNAc transferase gene family involved in the initiation of mucin-type O-glycosylation. Male Galnt3-deficient (Galnt3(-/-)) mice were infertile, as previously reported by Ichikawa et al. (2009). To investigate the involvement of Galnt3 in spermatogenesis, we examined the differentiation of germ cells in Galnt3(-/-) mice. Galnt3 mRNA was most highly expressed in testis, and Galnt3 protein was localized in the cis-medial parts of the Golgi stacks of spermatocytes and spermatids in the seminiferous tubules. Spermatozoa in Galnt3(-/-) mice were rare and immotile, and most of them had deformed round heads. They exhibited abnormal acrosome and disturbed mitochondria arrangement in the flagella. At the cap phase, proacrosomal vesicles of various sizes, which had not coalesced to form a single acrosomal vesicle, were attached to the nucleus in Galnt3(-/-) mice. TUNEL-positive cells were increased in the seminiferous tubules. The binding of VVA lectin, which recognizes the Tn antigen (GalNAc-O-Ser/Thr), in the acrosomal regions of spermatids and spermatozoa in Galnt3(-/-) mice was drastically reduced. Equatorin is a N, O-sialoglycoprotein localized in the acrosomal membrane and is suggested to be involved in sperm-egg interaction. Immunohistochemical and Western blot analyses showed a drastic reduction in the reactivity with MN9 antibody, which recognizes the O-glycosylated moiety of equatorin and inhibits sperm-egg interaction. These findings indicate that deficiency of Galnt3 results in a severe reduction of mucin-type O-glycans in spermatids and causes impaired acrosome formation, leading to oligoasthenoteratozoospermia, and suggest that Galnt3 may also be involved in the process of fertilization through the O-glycosylation of equatorin.


Assuntos
Acrossomo/metabolismo , Acrossomo/patologia , Astenozoospermia/metabolismo , Astenozoospermia/patologia , N-Acetilgalactosaminiltransferases/deficiência , Oligospermia/metabolismo , Oligospermia/patologia , Animais , Apoptose , Astenozoospermia/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Knockout , N-Acetilgalactosaminiltransferases/genética , Oligospermia/genética , Espermatozoides/anormalidades , Espermatozoides/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
12.
PLoS One ; 7(3): e32364, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22396760

RESUMO

RUNX2 and SP7 are essential transcription factors for osteoblast differentiation at an early stage. Although RUNX2 inhibits osteoblast differentiation at a late stage, the function of SP7 at the late stage of osteoblast differentiation is not fully elucidated. Thus, we pursued the function of SP7 in osteoblast differentiation. RUNX2 induced Sp7 expression in Runx2(-/-) calvarial cells. Adenoviral transfer of sh-Sp7 into primary osteoblasts reduced the expression of Alpl, Col1a1, and Bglap2 and mineralization, whereas that of Sp7 reduced Bglap2 expression and mineralization at a late stage of osteoblast differentiation. Sp7 transgenic mice under the control of 2.3 kb Col1a1 promoter showed osteopenia and woven-bone like structure in the cortical bone, which was thin and less mineralized, in a dose-dependent manner. Further, the number of processes in the osteoblasts and osteocytes was reduced. Although the osteoblast density was increased, the bone formation was reduced. The frequency of BrdU incorporation was increased in the osteoblastic cells, while the expression of Col1a1, Spp1, Ibsp, and Bglap2 was reduced. Further, the osteopenia in Sp7 or Runx2 transgenic mice was worsened in Sp7/Runx2 double transgenic mice and the expression of Col1a1 and Bglap2 was reduced. The expression of Sp7 and Runx2 was not increased in Runx2 and Sp7 transgenic mice, respectively. The expression of endogenous Sp7 was increased in Sp7 transgenic mice and Sp7-transduced cells; the introduction of Sp7 activated and sh-Sp7 inhibited Sp7 promoter; and ChIP assay showed the binding of endogenous SP7 in the proximal region of Sp7 promoter. These findings suggest that SP7 and RUNX2 inhibit osteoblast differentiation at a late stage in a manner independent of RUNX2 and SP7, respectively, and SP7 positively regulates its own promoter.


Assuntos
Diferenciação Celular , Regulação da Expressão Gênica , Osteoblastos/citologia , Fatores de Transcrição/metabolismo , Animais , Osso e Ossos/metabolismo , Imunoprecipitação da Cromatina , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/fisiologia , Genes Reporter , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Osteoblastos/metabolismo , Osteócitos/citologia , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fator de Transcrição Sp7 , Regulação para Cima
14.
Bioorg Med Chem Lett ; 22(2): 1251-4, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22177082

RESUMO

The lactoside with PEG-fluorous tag was introduced to BHK-21(C-13) cells to generate a GM3-type oligosaccharide (Siaα2-3Galß1-4Glc). The GM3-type oligosaccharide obtained was easily immobilized by spotting onto commercially available polytetrafluoroethylene (PTFE) filter through non-covalent fluorous affinity and simply assessed by dot blot method using the interaction of carbohydrate- with proteins which recognize sialic acid such as virus membrane proteins.


Assuntos
Vírus da Influenza A/química , Oligossacarídeos/química , Politetrafluoretileno/química , Animais , Linhagem Celular , Cricetinae , Membranas Artificiais , Polietilenoglicóis/química
15.
J Histochem Cytochem ; 59(1): 98-105, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20876522

RESUMO

Helicobacter pylori (H. pylori) is the causative pathogen underlying gastric diseases such as chronic gastritis and gastric cancer. Previously, the authors revealed that α1,4-linked N-acetylglucosamine-capped O-glycan (αGlcNAc) found in gland mucin suppresses H. pylori growth and motility by inhibiting catalytic activity of cholesterol α-glucosyltransferase (CHLαGcT), the enzyme responsible for biosynthesis of the major cell wall component cholesteryl-α-D-glucopyranoside (CGL). Here, the authors developed a polyclonal antibody specific for CHLαGcT and then undertook quantitative ultrastructural analysis of the enzyme's localization in H. pylori. They show that 66.3% of CHLαGcT is detected in the cytoplasm beneath the H. pylori inner membrane, whereas 24.7% is present on the inner membrane. In addition, 2.6%, 5.0%, and 1.4% of the protein were detected in the periplasm, on the outer membrane, and outside microbes, respectively. By using an in vitro CHLαGcT assay with fractionated H. pylori proteins, which were used as an enzyme source for CHLαGcT, the authors demonstrated that the membrane fraction formed CGL, whereas other fractions did not. These data combined together indicate that CHLαGcT is originally synthesized in the cytoplasm of H. pylori as an inactive form and then activated when it is associated with the cell membrane. This article contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.


Assuntos
Membrana Celular/metabolismo , Colesterol/análogos & derivados , Glucosiltransferases/metabolismo , Helicobacter pylori/citologia , Helicobacter pylori/enzimologia , Anticorpos/imunologia , Especificidade de Anticorpos , Colesterol/biossíntese , Ativação Enzimática , Glucosiltransferases/análise , Glucosiltransferases/química , Glucosiltransferases/imunologia , Helicobacter pylori/metabolismo , Helicobacter pylori/fisiologia , Espaço Intracelular/enzimologia , Espaço Intracelular/metabolismo , Microscopia Imunoeletrônica , Transporte Proteico
16.
J Leukoc Biol ; 87(6): 1133-43, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20145198

RESUMO

Vpr, a HIV-1 accessory protein, was believed to be present in the plasma of HIV-1-positive patients, and our previous work demonstrated the presence of plasma Vpr in 20 out of 52 patients. Interestingly, our data revealed that patients' viral titer was correlated with the level of Vpr detected in their plasma. Here, we first show that rVpr, when incubated with human monocytes or MDMs, caused viral production from latently infected cells, and IL-6 was identified as a responsible factor. The induction of IL-6 by rVpr was dependent on signaling through TLR4 and its adaptor molecule, MyD88. We next provide evidence that rVpr induced the formation of OxPC and that a mAb against OxPC blocked rVpr-induced IL-6 production with the concomitant attenuation of MAPK activation. Moreover, the addition of NAC, a scavenger of ROS, abrogated the rVpr-induced formation of OxPC, the phosphorylation of C/EBP-beta, a substrate of MAPK, and IL-6 production. As rIL-6 reactivated viral replication in latently infected cells, our data indicate that rVpr-induced oxidative stress triggers cell-based innate immune responses and reactivates viral production in latently infected cells via IL-6 production. Our results suggest that Vpr should be monitored based on the viral titer, and they provide the rationale for the development of novel, anti-AIDS therapeutics targeting Vpr.


Assuntos
Interleucina-6/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Ativação Viral , Latência Viral , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/metabolismo , Western Blotting , Proteína beta Intensificadora de Ligação a CCAAT/antagonistas & inibidores , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Células Cultivadas , Humanos , Imunidade Inata , Interleucina-6/genética , Sistema de Sinalização das MAP Quinases , Monócitos/citologia , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Oxirredução , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Regiões Promotoras Genéticas/genética , Análise Serial de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética , Replicação Viral , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/genética
17.
Jpn J Ophthalmol ; 49(5): 411-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16187043

RESUMO

BACKGROUND: The pathogenesis of optic disc pit maculopathy is still unknown, although recent optical coherence tomographic (OCT) analyses have made a great contribution to clarifying its morphological appearance. The best treatment for this disease is also controversial. CASE: We report on a 7-year-old girl with optic disc pit maculopathy associated with a separation of the internal limiting membrane (ILM) near the optic disc. OBSERVATIONS: The OCT images before treatment showed a conduit from the perineural space to the schisislike separation of the sensory retina with a dome-shaped separation of the ILM. A serous detachment (SD) in the macula, centered on the fovea, was also present. In OCT images after laser photocoagulation, the conduit appeared to be closed, but the SD was still present. Vitrectomy with ILM removal and gas tamponade resulted in a marked reduction of the SD in the macular area. Focal macular electroretinograms and visual acuity demonstrated a recovery of macular function. CONCLUSION: The dome-shaped separation of the ILM suggested that the vitreous might be exerting a tractional force on the optic disc pit, and vitrectomy with ILM peeling released the traction on the optic disc pit.


Assuntos
Membrana Epirretiniana/cirurgia , Anormalidades do Olho/cirurgia , Fotocoagulação a Laser , Disco Óptico/anormalidades , Vitrectomia/métodos , Membrana Basal/patologia , Membrana Basal/cirurgia , Criança , Eletrorretinografia , Membrana Epirretiniana/diagnóstico , Anormalidades do Olho/diagnóstico , Feminino , Humanos , Disco Óptico/patologia , Tomografia de Coerência Óptica , Acuidade Visual
18.
Chromosome Res ; 12(7): 741-54, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15505409

RESUMO

In order to seek chicken W chromosome-linked genes expressed significantly earlier than the time of gonadal differentiation, female-minus-male-subtracted cDNA macroarrays were prepared from day 2 (Hamburger-Hamilton stages 12-13), day 3 (stages 19-20) and day 4 (stages 24-25) embryos. From a total of 15-744 macroarrayed cDNA clones, 610 clones exhibiting significantly female-specific expression were selected. When each one of the 610 cDNA clones was used as a probe in Southern blot hybridization with male or female chicken genomic DNA, 62 clones, grouped into eight (A-H) types according to their patterns of hybridization, were considered to be derived from W chromosome-linked genes. When representative cDNA clones in each type were sequenced, clones derived from two known W-linked genes; SPIN-W and ATP5A1W , and from two hitherto unknown W-linked genes, represented by 2d-2D9 and 2d-2F9 clones, were identified and their localizations on the W chromosome were confirmed by fluorescence in-situ hybridization. The 2d-2D9 sequence has no significant homology with other genes in databases but 2d-2F9 has a region which shows partial homology to the consensus sequence of the AAA ATPase superfamily. Both 2d-2D9 and 2d-2F9 sequences are found in contigs of undetermined chromosome-linkage in the Draft Chicken Genome Sequence.


Assuntos
Galinhas/genética , Cromossomos Sexuais , Animais , Embrião de Galinha , DNA Complementar , Feminino , Perfilação da Expressão Gênica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Homologia de Sequência do Ácido Nucleico
19.
Am J Ophthalmol ; 136(1): 62-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12834671

RESUMO

PURPOSE: To determine the morphology of macular pseudoholes (MPHs) and the relationship of morphology to macular function. DESIGN: Observational case series. METHODS: Optical coherence tomography (OCT) was performed on 42 eyes of 42 consecutive patients with an epiretinal membrane (ERM) and an MPH. The diameters of the MPH, and the thickness of the foveal and parafoveal retina were measured. Of these 42 eyes, focal macular electroretinograms (FMERGs) were recorded from 22 eyes of 22 patients with a 15 degree stimulus; FMERGs were also recorded with a 5 degree stimulus from 9 eyes of these 22 eyes. RESULTS: In 42 eyes, the mean +/- Standard deviation (SD) diameter (437.7 +/- 172.8 microm) and geometrical shape of the MPHs were not significantly correlated with the visual acuity. The MPHs were divided into 2 types from the OCT images at the base of MPHs; group A had normal thickness (100-199 microm; n = 29), and group B (n = 13) had thicknesses of >or= 200 microm, or thickness < 100 microm, or irregular base. The visual acuity in group A (logarithm of the minimum angle of resolution [log MAR] mean +/- SD:.083 +/-.144) was significantly better than group B (log MAR,.407 +/-.212, P <.0001). There was a significant reduction in the amplitude of all components of FMERGs elicited by the 15 degree stimulus in the affected eyes (mean +/- SE, A-wave: 1.26 +/-.12 microv, B-wave: 3.07 +/-.27 microv, oscillatory potentials: 1.23 +/-.25 microv) compared with the normal fellow eyes (A-wave: 1.58 +/-.13 microv, B-wave: 4.14 +/-.27 microv, oscillatory potentials: 2.35 +/-.29 microv). A significant correlation was found between the relative amplitudes of the B-wave elicited by the 5 degree stimulus and the visual acuity (r =.918, P =.0005). CONCLUSIONS: In eyes with an ERM and an MPH, the visual acuity is generally correlated with the OCT images. Macular function of eyes with an MPH resembles eyes with an ERM without an MPH. The effect of the ERM appears to be different on the base and parafovea of the MPHs.


Assuntos
Membrana Epirretiniana/patologia , Membrana Epirretiniana/fisiopatologia , Macula Lutea/fisiologia , Perfurações Retinianas/patologia , Perfurações Retinianas/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrorretinografia , Feminino , Fóvea Central , Humanos , Interferometria , Masculino , Pessoa de Meia-Idade , Tomografia , Acuidade Visual/fisiologia
20.
Ophthalmic Res ; 35(4): 192-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12815194

RESUMO

AIMS: To determine the effect of preoperative factors on the foveal thickness following vitrectomy for diabetic macular edema. METHODS: Fifty-eight eyes of 47 patients underwent vitrectomy for diabetic macular edema. In all eyes, no clear, visible vitreomacular traction was present. Twelve eyes were pseudophakic before vitrectomy, and 31 eyes underwent concurrent phacoemulsification and intraocular lens (IOL) implantation. Multiple logistic regression analysis was used to assess the independent effect of age, history of photocoagulation, diabetic retinopathy status, preoperative posterior vitreous detachment, HbA(1c) and serum creatinine levels within 2 weeks before surgery, lens status after surgery and follow-up period on the foveal thickness determined by optical coherence tomography. RESULTS: The median preoperative visual acuity was 20/100 (range from 20/500 to 20/20), and the median postoperative visual acuity was 20/70 (range from 20/500 to 20/13). The preoperative visual acuity (logarithm of minimal angle of resolution; logMAR) was 0.73 +/- 0.36 (mean +/- SD; 20/107 Snellen acuity), and the mean postoperative logMAR visual acuity was 0.60 +/- 0.39 (20/80), which was significantly better than the mean preoperative value (Wilcoxon signed rank test, p = 0.011). The mean +/- SD of preoperative foveal thickness was 475.9 +/- 172.5 micrometer, and the mean postoperative foveal thickness was 277.3 +/- 171.9 micrometer. The mean postoperative foveal thickness was significantly thinner than the preoperative thickness (Student's paired t test, p < 0.0001). Multiple logistic regression analysis showed that a preoperative low HbA(1c) and postoperative pseudophakia were independently associated with the decrease in foveal thickness (p = 0.01, p = 0.04, respectively). CONCLUSIONS: The greater reduction in foveal thickness in eyes with an IOL probably resulted from a relatively larger amount of vitreous being removed during the vitrectomy. Because the decrease in foveal thickness may be related to the preoperative glycemic control and the amount of vitreous, these factors should be considered in the planning for vitrectomy.


Assuntos
Creatinina/sangue , Retinopatia Diabética/cirurgia , Hemoglobinas Glicadas/análise , Edema Macular/cirurgia , Vitrectomia , Adulto , Idoso , Retinopatia Diabética/sangue , Retinopatia Diabética/fisiopatologia , Humanos , Interferometria , Rim/fisiopatologia , Testes de Função Renal , Luz , Edema Macular/sangue , Edema Macular/fisiopatologia , Pessoa de Meia-Idade , Tomografia/métodos , Acuidade Visual
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