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1.
Immunohorizons ; 5(8): 703-710, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433625

RESUMO

Allergic skin inflammation requires the influx of inflammatory cells into the skin. Extravasation of leukocytes into the skin requires interactions between endothelial selectins and their glycan ligands on the surface of leukocytes. Selectin-ligand formation requires the activity of several glycosyltransferases, including Fut7 In this report, we tested the importance of Fut7 for the development of allergic skin inflammation in the Stat6VT transgenic mouse model. We observed that Fut7 deficiency was protective but did not eliminate disease. Segregation of the data by gender of the parent that transmitted the Stat6VT transgene, but not by gender of the pups, which were analyzed for disease, revealed that the protective effects of Fut7 deficiency were significantly greater when dams were Stat6VT negative. In contrast, in mice from litters of Stat6VT+ dams, Fut7 deficiency resulted in only modest protection. These findings indicate that pups from atopic dams exhibit a greater propensity for allergic disease, similar to observations in humans, and that the effect of maternal atopy is due to enhanced selectin-independent mechanisms of leukocyte recruitment in their offspring. Together, these results demonstrate that Fut7 deficiency can be protective in a model of atopic dermatitis but that maternal atopy diminishes these protective effects, suggesting alternative pathways for leukocyte recruitment in the absence of Fut7 enzyme activity. These observations have implications for understanding how the environment in utero predisposes for the development of allergic disease.


Assuntos
Dermatite Atópica/imunologia , Selectina E/imunologia , Imunidade Materno-Adquirida/imunologia , Inflamação/imunologia , Selectina-P/imunologia , Pele/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Dermatite Atópica/genética , Dermatite Atópica/metabolismo , Selectina E/metabolismo , Fucosiltransferases/deficiência , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Humanos , Imunidade Materno-Adquirida/genética , Inflamação/genética , Inflamação/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Selectina-P/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/imunologia , Fator de Transcrição STAT6/metabolismo , Pele/metabolismo , Pele/patologia
2.
Front Immunol ; 12: 704309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421910

RESUMO

CD147, a member of the immunoglobulin (Ig) superfamily, is widely expressed in several cell types. CD147 molecules have multiple cellular functions, such as migration, adhesion, invasion, energy metabolism and T cell activation. In particular, recent studies have demonstrated the potential application of CD147 as an effective therapeutic target for cancer, as well as autoimmune and inflammatory diseases. In this study, we elucidated the functional epitopes on CD147 extracellular domains in T cell regulation using specific monoclonal antibodies (mAbs). Upon T cell activation, the anti-CD147 domain 1 mAbs M6-1E9 and M6-1D4 and the anti-CD147 domain 2 mAb MEM-M6/6 significantly reduced surface expression of CD69 and CD25 and T cell proliferation. To investigate whether functional epitopes of CD147 are differentially expressed on distinct leukocyte subsets, PBMCs, monocyte-depleted PBMCs and purified T cells were activated in the presence of anti-CD147 mAbs. The mAb M6-1E9 inhibited T cell functions via activation of CD147 on monocytes with obligatory cell-cell contact. Engagement of the CD147 epitope by the M6-1E9 mAb downregulated CD80 and CD86 expression on monocytes and IL-2, TNF-α, IFN-γ and IL-17 production in T cells. In contrast, the mAb M6-1D4 inhibited T cell function via activation of CD147 on T cells by downregulating IL-2, TNF-α and IFN-γ. Herein, we demonstrated that certain epitopes of CD147, expressed on both monocytes and T cells, are involved in the regulation of T cell activation.


Assuntos
Proliferação de Células , Epitopos/imunologia , Fucosiltransferases/imunologia , Ativação Linfocitária , Monócitos/imunologia , Linfócitos T/imunologia , Anticorpos Monoclonais Murinos/imunologia , Anticorpos Monoclonais Murinos/farmacologia , Humanos
3.
Viruses ; 13(6)2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198720

RESUMO

Histo-blood group antigens, which are present on gut epithelial surfaces, function as receptors or attachment factors and mediate susceptibility to rotavirus infection. The major determinant for susceptibility is a functional FUT2 enzyme which mediates the presence of α-1,2 fucosylated blood group antigens in mucosa and secretions, yielding the secretor-positive phenotype. Secretors are more susceptible to infection with predominant rotavirus genotypes, as well as to the commonly used live rotavirus vaccines. Difference in susceptibility to the vaccines is one proposed factor for the varying degree of efficacy observed between countries. Besides infection susceptibility, secretor status has been found to modulate rotavirus specific antibody levels in adults, as well as composition of breastmilk in mothers and microbiota of the infant, which are other proposed factors affecting rotavirus vaccine take. Here, the known and possible effects of secretor status in both infant and mother on rotavirus vaccine take are reviewed and discussed.


Assuntos
Antígenos de Grupos Sanguíneos/imunologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Anticorpos Antivirais/sangue , Antígenos de Grupos Sanguíneos/genética , Feminino , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Genótipo , Humanos , Lactente , Mães , Fenótipo , Rotavirus/genética , Rotavirus/imunologia , Vacinas contra Rotavirus/administração & dosagem , Galactosídeo 2-alfa-L-Fucosiltransferase
4.
Sci Rep ; 11(1): 3186, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542434

RESUMO

The expression of ABO antigens in human saliva is regulated by the FUT2 gene, which encodes a secretor type α(1,2)fucosyltransferase. Secretors express ABO substrates in saliva and non-secretors do not. Secretor status is an object of concern, especially for susceptibility to various infectious diseases. A multitude of single nucleotide polymorphisms (SNPs) and copy number variations (CNVs) have been reported, and they show unique distributions among different populations. In this study, we selected 18 uncharacterized FUT2 alleles listed in the Erythrogene database and obtained genomic DNA having these alleles. We experimentally confirmed the haplotypes, but 10 of 18 alleles disagreed with those in the database, which may be attributed to their low frequency. We then examined the activity of the encoded α(1,2)fucosyltransferase for 13 alleles by flow cytometry of H antigen expression. The impact of each nonsynonymous SNP on the enzyme was also estimated by software. We finally identified two non-secretor alleles (se610and se357,856,863) and one weak secretor allele (se262,357), while in silico analysis predicted that many alleles impair the function. The present results suggest that correct haplotyping and functional assays are desirable for analysis of the FUT2 gene.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Alelos , Fucosiltransferases/genética , Polimorfismo de Nucleotídeo Único , Saliva/enzimologia , Sistema ABO de Grupos Sanguíneos/classificação , Sistema ABO de Grupos Sanguíneos/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Variações do Número de Cópias de DNA , Bases de Dados Genéticas , Fucosiltransferases/imunologia , Expressão Gênica , Frequência do Gene , Haplótipos , Humanos , Saliva/química , Saliva/imunologia , Galactosídeo 2-alfa-L-Fucosiltransferase
5.
Int J Mol Sci ; 22(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573215

RESUMO

This study was conducted to explore whether trichostatin A-assisted epigenomic modulation (TSA-EM) can affect the expression of not only recombinant human α1,2-fucosyltransferase (rhα1,2-FT) and α-galactosidase A (rhα-Gal A) immune system enzymes but also Galα1→3Gal epitopes in ex vivo proliferating adult cutaneous fibroblast cells (ACFCs) derived from hFUT2×hGLA bi-transgenic pigs that had been produced for the needs of future xenotransplantation efforts. The ACFC lines were treated with 50 nM TSA for 24 h and then the expression profiles of rhα1,2-FT and rhα-Gal A enzymes were analyzed by Western blot and immunofluorescence. The expression profiles of the Galα1→3Gal epitope were determined by lectin blotting and lectin fluorescence. The ACFCs derived from non-transgenic (nTG) pigs were served as the negative (TSA-) and positive (TSA+) control groups. For both hFUT2×hGLA and nTG samples, the expression levels of α1,2-FT and α-Gal A proteins in TSA+ cells were more than twofold higher in comparison to TSA- cells. Moreover, a much lower expression of the Galα1→3Gal epitopes was shown in TSA- hFUT2×hGLA cells as compared to the TSA- nTG group. Interestingly, the levels of Galα1→3Gal expression in TSA-treated hFUT2×hGLA and nTG ACFCs were significantly higher than those noticed for their TSA-untreated counterparts. Summing up, ex vivo protection of effectively selected bi-transgenic ACFC lines, in which TSA-dependent epigenetic transformation triggered the enhancements in reprogrammability and subsequent expression of hFUT2 and hGLA transgenes and their corresponding transcripts, allows for cryopreservation of nuclear donor cells, nuclear-transferred female gametes, and resultant porcine cloned embryos. The latter can be used as a cryogenically conserved genetic resource of biological materials suitable for generation of bi-transgenic cloned offspring in pigs that is targeted at biomedical research in the field of cell/tissue xenotransplantation.


Assuntos
Epigênese Genética/efeitos dos fármacos , Epitopos/metabolismo , Rejeição de Enxerto/prevenção & controle , Ácidos Hidroxâmicos/farmacologia , Transplante Heterólogo/efeitos adversos , Animais , Animais Geneticamente Modificados , Linhagem Celular , Clonagem de Organismos/métodos , Criopreservação , Embrião de Mamíferos , Epitopos/genética , Epitopos/imunologia , Fibroblastos , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Fucosiltransferases/metabolismo , Técnicas de Inativação de Genes , Rejeição de Enxerto/imunologia , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Pele/citologia , Suínos , Transplante Heterólogo/métodos , alfa-Galactosidase/genética , alfa-Galactosidase/imunologia , alfa-Galactosidase/metabolismo , Galactosídeo 2-alfa-L-Fucosiltransferase
6.
J Microbiol Immunol Infect ; 54(4): 606-615, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32146162

RESUMO

BACKGROUND: The humoral immune response is pivotal to protect the host from Salmonella typhimurium (S. typhimurium) infection. Previously, we found that core fucosylation catalyzed by core fucosyltransferase (Fut8) could regulate the immune responses. However, the role of core fucosylation during S. typhimurium infection remains unclear. METHODS: To demonstrate the role of Fut8 in S. typhimurium infection, we infected Fut8+/+ and Fut8-/- mice using S. typhimurium. The production of antiserum against the S. typhimurium was detected. The expression of T and B cell activation-related genes during S. typhimurium infection was analyzed. The role of core fucosylation on CD4+ T-B cell interaction and B cell generation was investigated during S. typhimurium infection. The production of sIgA was compared between Fut8+/+ and Fut8-/- mice. RESULTS: Compared to Fut8+/+ mice, the number of S. typhimurium colonized in the cecum was markedly increased in Fut8-/- mice. The production of the IgG and sIgA specific for S. typhimurium was significantly decreased in Fut8-/- mice. Moreover, loss of Fut8 decreased the induction of Th2-type cytokines from splenic cells of Fut8-/- mice during S. typhimurium infection. In addition, we found that the core fucosylation regulated the interaction between B and T cells in the lipid raft formation. CONCLUSION: Core fucosylation plays important roles in host defence against S. typhimurium infection.


Assuntos
Fucose/metabolismo , Fucosiltransferases/metabolismo , Imunidade Humoral , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Animais , Fucose/imunologia , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Linfócitos T/imunologia
7.
Eur J Immunol ; 50(11): 1820-1833, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32460355

RESUMO

As an immune checkpoint, programmed cell death 1 (PD-1) and its ligand (PD-L1) pathway plays a crucial role in CD8+ cytotoxic T lymphocytes (CTL) activation and provides antitumor responses. The N-glycans of PD-1 and PD-L1 are highly core fucosylated, which are solely catalyzed by the core fucosyltransferase (Fut8). However, the precise biological mechanisms underlying effects of core fucosylation of PD-1 and PD-L1 on CTL activation have not been fully understood. In this study, we found that core fucosylation was significantly upregulated in lung adenocarcinoma. Compared to those of Fut8+/+ OT-I mice, the lung adenocarcinoma formation induced by urethane was markedly reduced in Fut8-/- OT-I mice. De-core fucosylation of PD-1 compromised its expression on Fut8-/- CTL, resulted in enhanced Fut8-/- CTL activation and cytotoxicity, leading to more efficient tumor eradication. Indeed, loss of core fucosylation significantly enhanced the PD-1 ubiquitination and in turn led to the degradation of PD-1 in the proteasome. Our current work indicates that inhibition of core fucosylation is a unique strategy to reduce PD-1 expression for the antilung adenocarcinoma immune therapy in the future.


Assuntos
Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/terapia , Antineoplásicos/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/terapia , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Citotóxicos/imunologia , Células A549 , Animais , Linhagem Celular , Linhagem Celular Tumoral , Fucosiltransferases/imunologia , Glicosilação , Células HEK293 , Humanos , Ativação Linfocitária/imunologia , Camundongos , Transdução de Sinais/imunologia , Regulação para Cima/imunologia
8.
PLoS Genet ; 15(11): e1008497, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31747390

RESUMO

The lipopolysaccharide O-antigen structure expressed by the European Helicobacter pylori model strain G27 encompasses a trisaccharide, an intervening glucan-heptan and distal Lewis antigens that promote immune escape. However, several gaps still remain in the corresponding biosynthetic pathway. Here, systematic mutagenesis of glycosyltransferase genes in G27 combined with lipopolysaccharide structural analysis, uncovered HP0102 as the trisaccharide fucosyltransferase, HP1283 as the heptan transferase, and HP1578 as the GlcNAc transferase that initiates the synthesis of Lewis antigens onto the heptan motif. Comparative genomic analysis of G27 lipopolysaccharide biosynthetic genes in strains of different ethnic origin revealed that East-Asian strains lack the HP1283/HP1578 genes but contain an additional copy of HP1105 and JHP0562. Further correlation of different lipopolysaccharide structures with corresponding gene contents led us to propose that the second copy of HP1105 and the JHP0562 may function as the GlcNAc and Gal transferase, respectively, to initiate synthesis of the Lewis antigen onto the Glc-Trio-Core in East-Asian strains lacking the HP1283/HP1578 genes. In view of the high gastric cancer rate in East Asia, the absence of the HP1283/HP1578 genes in East-Asian H. pylori strains warrants future studies addressing the role of the lipopolysaccharide heptan in pathogenesis.


Assuntos
Infecções por Helicobacter/genética , Lipopolissacarídeos/genética , Antígenos O/genética , Neoplasias Gástricas/genética , Povo Asiático , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Glucanos/genética , Glicosiltransferases/genética , Glicosiltransferases/imunologia , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , Antígenos do Grupo Sanguíneo de Lewis/genética , Antígenos do Grupo Sanguíneo de Lewis/imunologia , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Mutagênese , Antígenos O/imunologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia
9.
Mol Immunol ; 112: 312-321, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229844

RESUMO

Precise glycosylation plays a crucial and distinctive role in thymic T cell development. The core fucosylation is dramatically up-regulated at the transition from CD4-CD8- (DN) to CD4+CD8+ (DP) in the thymic development. Ablation of core fucosylation in T cells did reduce the size of the thymus due to a significant loss of CD4+ SP, CD8+ SP and DP thymocytes in core fucosyltransferase (Fut8) knockout (Fut8-/-) mice. T cell receptors (TCRs) are heavily core fucosylated glycoproteins. Loss of core fucosylation of TCR contributed to the reduced phosphorylation of ZAP70 (pZAP70) in Fut8-/- DP cells was observed. Compare to the Fut8+/+OT-II DP thymocytes, pZAP70 was significantly reduced in Fut8-/- OT-II DP thymocytes with OVA323-339 stimulation. Also, the pZAP70 of Fut8+/+OT-I DP thymocytes with OVA257-264 stimulation was remarkably attenuated by treatment of the fucosidase. Upon anti-CD3/CD28 Abs stimulation, the increased apoptosis was found in Fut8-/- thymocytes compared with Fut8+/+ thymocytes. Moreover, the TCRhiCD69hi (post-positive selection thymocytes) was markedly depleted in the Fut8-/- thymus without any stimulation. The expression of CD5 was significantly down-regulated on the DP cells in the Fut8-/- thymus. Our results therefore demonstrate that ablation of core fucosylation results in the abnormal T cell development due to the attenuated signaling via TCR.


Assuntos
Fucose/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Apoptose/imunologia , Antígenos CD5/imunologia , Diferenciação Celular/imunologia , Fucosiltransferases/imunologia , Glicosilação , Lectinas Tipo C/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/imunologia , Timócitos/imunologia , Proteína-Tirosina Quinase ZAP-70/imunologia
10.
J Allergy Clin Immunol ; 144(3): 698-709.e9, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31125592

RESUMO

BACKGROUND: One of the pathognomonic features of asthma is epithelial hyperproduction of mucus, which is composed of a series of glycoproteins; however, it remains unclear how glycosylation is induced in lung epithelial cells from asthmatic patients and how glycan residues play a role in the pathogenesis of asthma. OBJECTIVE: The objective of this study was to explore comprehensive epithelial glycosylation status induced by allergic inflammation and reveal its possible role in the pathogenesis of asthma. METHODS: We evaluated the glycosylation status of lung epithelium using a lectin microarray. We next searched for molecular mechanisms underlying epithelial glycosylation. We also examined whether epithelial glycosylation is involved in induction of allergic inflammation. RESULTS: On allergen inhalation, lung epithelial cells were heavily α(1,2)fucosylated by fucosyltransferase 2 (Fut2), which was induced by the IL-13-signal transducer and activator of transcription 6 pathway. Importantly, Fut2-deficient (Fut2-/-) mice, which lacked lung epithelial fucosylation, showed significantly attenuated eosinophilic inflammation and airway hyperresponsiveness in house dust mite (HDM)-induced asthma models. Proteome analyses and immunostaining of the HDM-challenged lung identified that complement C3 was accumulated in fucosylated areas. Indeed, Fut2-/- mice showed significantly reduced levels of C3a and impaired accumulation of C3a receptor-expressing monocyte-derived dendritic cells in the lung on HDM challenge. CONCLUSION: Fut2 induces epithelial fucosylation and exacerbates airway inflammation in asthmatic patients in part through C3a production and monocyte-derived dendritic cell accumulation in the lung.


Assuntos
Asma/imunologia , Células Epiteliais/imunologia , Fucosiltransferases/imunologia , Pulmão/imunologia , Mucosa Respiratória/imunologia , Alérgenos/imunologia , Animais , Complemento C3/imunologia , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Eosinofilia Pulmonar/imunologia , Pyroglyphidae/imunologia , Células Th17/imunologia , Células Th2/imunologia , Galactosídeo 2-alfa-L-Fucosiltransferase
11.
Vaccine ; 37(34): 4805-4810, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30709726

RESUMO

Thanks to the modern sequencing era, the extent to which infectious disease imposes selective pressures on the worldwide human population is being revealed. This is aiding our understanding of the underlying immunological and host mechanistic defenses against these pathogens, as well as potentially assisting in the development of vaccines and therapeutics to control them. As a consequence, the workshop "How genomics can be used to understand host susceptibility to enteric infection, aiding in the development of vaccines and immunotherapeutic interventions" at the VASE 2018 meeting, aimed to discuss how genomics and related tools could be used to assist Shigella and ETEC vaccine development. The workshop featured four short presentations which highlighted how genomic applications can be used to assist in the identification of genetic patterns related to the virulence of disease, or host genetic factors that could contribute to immunity or successful vaccine responses. Following the presentations, there was an open debate with workshop attendees to discuss the best ways to utilise such genomic studies, to improve or accelerate the process of both Shigella and ETEC vaccine development. The workshop concluded by making specific recommendations on how genomic research methods could be strengthened and harmonised within the ETEC and Shigella research communities.


Assuntos
Diarreia/prevenção & controle , Disenteria Bacilar/prevenção & controle , Escherichia coli Enterotoxigênica/imunologia , Infecções por Escherichia coli/prevenção & controle , Predisposição Genética para Doença , Interações Hospedeiro-Patógeno/genética , Shigella/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Ensaios Clínicos como Assunto , Congressos como Assunto , Diarreia/genética , Diarreia/imunologia , Diarreia/microbiologia , Disenteria Bacilar/genética , Disenteria Bacilar/imunologia , Disenteria Bacilar/microbiologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Escherichia coli Enterotoxigênica/patogenicidade , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/biossíntese , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Genômica/métodos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunização/métodos , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/imunologia , Shigella/efeitos dos fármacos , Shigella/patogenicidade , Vacinas contra Shigella/administração & dosagem , Vacinas contra Shigella/biossíntese , Galactosídeo 2-alfa-L-Fucosiltransferase
12.
Cell Rep ; 20(5): 1017-1028, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28768188

RESUMO

Programmed cell death 1 (PD-1) is highly expressed on exhausted T cells and inhibits T cell activation. Antibodies that block the interaction between PD-1 and its ligand prevent this inhibitory signal and reverse T cell dysfunction, providing beneficial anti-tumor responses in a substantial number of patients. Mechanisms for the induction and maintenance of high PD-1 expression on exhausted T cells have not been fully understood. Utilizing a genome-wide loss-of-function screening method based on the CRISPR-Cas9 system, we identified genes involved in the core fucosylation pathway as positive regulators of cell-surface PD-1 expression. Inhibition of Fut8, a core fucosyltransferase, by genetic ablation or pharmacologic inhibition reduced cell-surface expression of PD-1 and enhanced T cell activation, leading to more efficient tumor eradication. Taken together, our findings suggest that blocking core fucosylation of PD-1 can be a promising strategy for improving anti-tumor immune responses.


Assuntos
Fucosiltransferases , Regulação Neoplásica da Expressão Gênica/imunologia , Imunidade Celular , Proteínas de Neoplasias , Neoplasias Experimentais , Receptor de Morte Celular Programada 1 , Linfócitos T/imunologia , Animais , Sistemas CRISPR-Cas , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Estudo de Associação Genômica Ampla , Glicosilação , Humanos , Ativação Linfocitária , Camundongos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/patologia
13.
PLoS One ; 12(6): e0179012, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28666020

RESUMO

Glioblastoma is the most common primary tumor of the brain and has few long-term survivors. The local and systemic immunosuppressive environment created by glioblastoma allows it to evade immunosurveillance. Myeloid-derived suppressor cells (MDSCs) are a critical component of this immunosuppression. Understanding mechanisms of MDSC formation and function are key to developing effective immunotherapies. In this study, we developed a novel model to reliably generate human MDSCs from healthy-donor CD14+ monocytes by culture in human glioma-conditioned media. Monocytic MDSC frequency was assessed by flow cytometry and confocal microscopy. The resulting MDSCs robustly inhibited T cell proliferation. A cytokine array identified multiple components of the GCM potentially contributing to MDSC generation, including Monocyte Chemoattractive Protein-1, interleukin-6, interleukin-8, and Macrophage Migration Inhibitory Factor (MIF). Of these, Macrophage Migration Inhibitory Factor is a particularly attractive therapeutic target as sulforaphane, a naturally occurring MIF inhibitor derived from broccoli sprouts, has excellent oral bioavailability. Sulforaphane inhibits the transformation of normal monocytes to MDSCs by glioma-conditioned media in vitro at pharmacologically relevant concentrations that are non-toxic to normal leukocytes. This is associated with a corresponding increase in mature dendritic cells. Interestingly, sulforaphane treatment had similar pro-inflammatory effects on normal monocytes in fresh media but specifically increased immature dendritic cells. Thus, we have used a simple in vitro model system to identify a novel contributor to glioblastoma immunosuppression for which a natural inhibitor exists that increases mature dendritic cell development at the expense of myeloid-derived suppressor cells when normal monocytes are exposed to glioma conditioned media.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Isotiocianatos/farmacologia , Células Supressoras Mieloides/efeitos dos fármacos , Neoplasias Encefálicas/imunologia , Antígeno CD11b/imunologia , Hipóxia Celular , Linhagem Celular Tumoral , Meios de Cultivo Condicionados , Fucosiltransferases/imunologia , Glioblastoma/imunologia , Humanos , Antígenos CD15/imunologia , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/patologia , Sulfóxidos
14.
Sci Rep ; 7: 41720, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139731

RESUMO

Histo-blood group ABO gene polymorphism is crucial in transfusion medicine. We studied the activity and subcellular distribution of ABO gene-encoded A glycosyltransferases with N-terminal truncation. We hypothesized that truncated enzymes starting at internal methionines drove the synthesis of oligosaccharide A antigen in those already described alleles that lack a proper translation initiation codon. Not only we tested the functionality of the mutant transferases by expressing them and assessing their capacity to drive the appearance of A antigen on the cell surface, but we also analyzed their subcellullar localization, which has not been described before. The results highlight the importance of the transmembrane domain because proteins deprived of it are not able to localize properly and deliver substantial amounts of antigen on the cell surface. Truncated proteins with their first amino acid well within the luminal domain are not properly localized and lose their enzymatic activity. Most importantly, we demonstrated that other codons than AUG might be used to start the protein synthesis rather than internal methionines in translation-initiation mutants, explaining the molecular mechanism by which transferases lacking a classical start codon are able to synthesize A/B antigens.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Alelos , Códon de Iniciação , Mutação , Sistema ABO de Grupos Sanguíneos/química , Sistema ABO de Grupos Sanguíneos/metabolismo , Membrana Celular/imunologia , Membrana Celular/metabolismo , Citometria de Fluxo , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Patrimônio Genético , Humanos , Biossíntese de Proteínas , Transporte Proteico , Deleção de Sequência , Galactosídeo 2-alfa-L-Fucosiltransferase
15.
J Proteome Res ; 16(1): 156-169, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-27351377

RESUMO

The human acute monocytic leukemia cell line THP-1 is widely used as an in vitro phagocytic cell model because it exhibits several immune properties similar to native monocyte-derived macrophages. In this study, we investigated the alteration of N- and O-linked glycans as well as glycosphingolipids, during THP-1 differentiation, combining mass spectrometry, flow cytometry, and quantitative real-time PCR. Mass spectrometry revealed that macrophage differentiation led to a marked upregulation of expression of GM3 ganglioside as well as an increase in complex-type structures, particularly triantennary glycans, occurring at the expense of high-mannose N-glycans. Moreover, we observed a slight decrease in the proportion of multifucosylated N-glycans and α2,6-sialylation. The uncovered changes in glycosylation correlated with variations of gene expression of relevant glycosyltransferases and glycosidases including sialyltransferases, ß-N-acetylglucosaminyltransferases, fucosyltransferases, and neuraminidase. Furthermore, using flow cytometry and antibodies directed against glycan structures, we confirmed that the alteration of glycosylation occurs at the cell surface of THP-1 macrophage-like cells. Altogether, we established that macrophagic maturation of THP-1 induces dramatic modifications of the surface glycosylation pattern that may result in differential interaction of monocytic and macrophagic THP-1 with immune or bacterial lectins.


Assuntos
Diferenciação Celular/imunologia , Glicoesfingolipídeos/química , Macrófagos/química , Monócitos/química , Polissacarídeos/química , Configuração de Carboidratos , Sequência de Carboidratos , Linhagem Celular , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Gangliosídeo G(M3)/química , Gangliosídeo G(M3)/imunologia , Regulação da Expressão Gênica , Glicoesfingolipídeos/imunologia , Glicosilação , Glicosiltransferases/genética , Glicosiltransferases/imunologia , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Manose/química , Manose/imunologia , Monócitos/citologia , Monócitos/imunologia , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/imunologia , Neuraminidase/genética , Neuraminidase/imunologia , Polissacarídeos/imunologia , Ácidos Siálicos/química , Ácidos Siálicos/imunologia , Sialiltransferases/genética , Sialiltransferases/imunologia
16.
J Autoimmun ; 66: 25-39, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26347073

RESUMO

Primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) represent the three major hepatic autoimmune conditions. Patient morbidity and mortality remain high across these three diseases, and an unmet need for rational therapy exists. Disease understanding has focused on combining clinical and laboratory based science to provide better insights into the joint host and environmental factors necessary for the initiation, and perpetuation, of hepato-biliary inflammation. Twin studies, family studies, population studies and an inter-relationship with other autoimmune phenomena suggest a genetic component to risk for each disease. Until recently, understanding of this genetic risk has been limited to HLA haplotypes. Associations with risk-conferring and protective HLA haplotypes are present in all three diseases. Over the last few years, genome-wide association studies (GWAS), and related genetic association studies, have greatly increased understanding of the genetic risk signature of these three diseases and autoimmunity in general. Here we consider the rationale for GWAS in general and with specific reference to hepatic autoimmunity. We consider the process of GWAS, and highlight major findings to date. Potential functional implications of key findings are discussed including the IL-12/STAT4 pathway in PBC and the CD28/IL-2 pathway in PSC. We describe the marked pleiotropy demonstrated by PBC and PSC, which is consistent with other autoimmune diseases. Further, we focus on specific gene associations including SH2B3, which is common to all three diseases, and FUT2 in PSC, which represents a link between environment and genetics. We review attempts to translate GWAS findings into basic laboratory models including in vivo systems and highlight where clinical observations relate to genetics. Finally we describe deficiencies in GWAS to date and consider future study of genetics in hepatic autoimmunity.


Assuntos
Autoimunidade/genética , Colangite Esclerosante/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hepatite Autoimune/genética , Cirrose Hepática Biliar/genética , Proteínas Adaptadoras de Transdução de Sinal , Antígenos CD28/genética , Antígenos CD28/metabolismo , Colangite Esclerosante/imunologia , Epistasia Genética , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Antígenos HLA/genética , Haplótipos , Hepatite Autoimune/imunologia , Humanos , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Fígado/imunologia , Cirrose Hepática Biliar/imunologia , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Proteínas/imunologia , Fatores de Risco , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Transdução de Sinais/imunologia , Galactosídeo 2-alfa-L-Fucosiltransferase
17.
Biomed Res Int ; 2015: 131054, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26583085

RESUMO

Neural stem cells in the adult mammalian brain have a significant level of neurogenesis plasticity. In vivo monitoring of adult endogenous NSCs would be of great benefit to the understanding of the neurogenesis plasticity under normal and pathological conditions. Here we show the feasibility of in vivo targeted MR imaging of endogenous NSCs in adult mouse brain by intraventricular delivery of monoclonal anti-CD15 antibody conjugated superparamagnetic iron oxide nanoparticles. After intraventricular administration of these nanoparticles, the subpopulation of NSCs in the anterior subventricular zone and the beginning of the rostral migratory stream could be in situ labeled and were in vivo visualized with 7.0-T MR imaging during a period from 1 day to 7 days after the injection. Histology confirmed that the injected targeted nanoparticles were specifically bound to CD15 positive cells and their surrounding extracellular matrix. Our results suggest that in vivo targeted MR imaging of endogenous neural stem cells in adult rodent brain could be achieved by using anti-CD15-SPIONs as the molecular probe; and this targeting imaging strategy has the advantage of a rapid in vivo monitoring of the subpopulation of endogenous NSCs in adult brains.


Assuntos
Encéfalo/diagnóstico por imagem , Células-Tronco Neurais/diagnóstico por imagem , Neurogênese , Neurônios/diagnóstico por imagem , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Encéfalo/fisiologia , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Fucosiltransferases/administração & dosagem , Fucosiltransferases/química , Fucosiltransferases/imunologia , Ferro/química , Imageamento por Ressonância Magnética , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Células-Tronco Neurais/fisiologia , Radiografia
19.
J Immunol ; 194(6): 2596-606, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25694612

RESUMO

Ag recognition and Ab production in B cells are major components of the humoral immune response. In the current study, we found that the core fucosylation catalyzed by α1,6-fucosyltransferase (Fut8) was required for the Ag recognition of BCR and the subsequent signal transduction. Moreover, compared with the 3-83 B cells, the coalescing of lipid rafts and Ag-BCR endocytosis were substantially reduced in Fut8-knockdown (3-83-KD) cells with p31 stimulation and then completely restored by reintroduction of the Fut8 gene to the 3-83-KD cells. Indeed, Fut8-null (Fut8(-/-)) mice evoked a low immune response following OVA immunization. Also, the frequency of IgG-producing cells was significantly reduced in the Fut8(-/-) spleen following OVA immunization. Our results clearly suggest an unexpected mode of BCR function, in which the core fucosylation of IgG-BCR mediates Ag recognition and, concomitantly, cell signal transduction via BCR and Ab production.


Assuntos
Formação de Anticorpos/imunologia , Antígenos/imunologia , Linfócitos B/imunologia , Imunoglobulina G/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Western Blotting , Células Cultivadas , Endocitose/imunologia , Citometria de Fluxo , Fucose/imunologia , Fucose/metabolismo , Fucosiltransferases/deficiência , Fucosiltransferases/genética , Fucosiltransferases/imunologia , Glicosilação , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Microdomínios da Membrana/imunologia , Microdomínios da Membrana/metabolismo , Camundongos Endogâmicos ICR , Camundongos Knockout , Dados de Sequência Molecular , Ovalbumina/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/imunologia , Baço/imunologia , Baço/metabolismo
20.
Arch Immunol Ther Exp (Warsz) ; 62(5): 411-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24554032

RESUMO

Hyperacute rejection (HAR) depends on the response of xenoreactive antibodies principally against porcine α-Gal epitope. Methods eliminating HAR include GGTA1 inactivation, regulation of the complement system and modification of the oligosaccharide structure of surface proteins in donor's cells. Transgenic animals designed for the purpose of xenotransplantation with single modification do not display full reduction of the α-Gal epitope level, which means that a accumulation of several modifications in one transgenic individual is needed. The aim of the study was to create a molecular and cytogenetic profile of a double transgenic animal with α1,2-fucosyltransferase and α-galactosidase expression. As a result of interbreeding of an individual with α1,2-fucosyltransferase expression with an individual with α-galactosidase expression 12 living piglets were obtained. PCR revealed the pCMVFUT gene construct was present in four individuals and pGAL-GFPBsd in three, including one with a confirmed integration of both the gene constructs. Fluorescence in situ hybridization confirmed the site of transgene integration, which corresponded to the mapping site of the transgenes which occurred in the parental generations. Karyotype analysis did not show any changes in the structure or the number of chromosomes (2n = 38, XX). As for the results pertaining to the single transgenic individuals, expression analysis demonstrated a high extent of α-Gal epitope level reduction on the surface of cells, whereas human serum cytotoxicity tests revealed the smallest decrease in longevity of cells in the obtained double transgenic individual (4.35 %). The tests suggest that the co-expression of both the transgenes leads to a considerable reduction of the α-Gal antigen level on the surface of cells and a decrease of xenotransplant immunogenicity.


Assuntos
Fibroblastos/fisiologia , Fucosiltransferases/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante Heterólogo , alfa-Galactosidase/imunologia , Animais , Animais Geneticamente Modificados , Citotoxicidade Celular Dependente de Anticorpos/genética , Linhagem Celular , Epitopos de Linfócito B/genética , Fucosiltransferases/genética , Rejeição de Enxerto/etiologia , Humanos , Imunidade Humoral/genética , Soro/imunologia , Suínos , alfa-Galactosidase/genética , Galactosídeo 2-alfa-L-Fucosiltransferase
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