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1.
NMC Case Rep J ; 11: 191-194, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39183799

RESUMO

Craniopharyngioma (CP) and Rathke's cleft cyst (RCC) are both suprasellar lesions. They are sometimes difficult to distinguish due to their similar findings. We report a case of papillary craniopharyngioma (pCP) with the clinical findings suggesting RCC. A 42-year-old female with intellectual disability presented to our hospital with severe visual dysfunction. Preoperative images revealed a suprasellar cystic lesion without calcification. We performed transsphenoidal surgery. Since the cyst had condensed-milk-like content suggesting RCC, we performed cyst fenestration and wash without removal of the cyst wall. Thereafter, we found fish-egg-like structures on the cyst wall. The histopathological analysis revealed that they had papillary structures surrounded by hyperplastic squamous epithelium with parakeratosis. Immunostaining for BRAF V600E was positive, leading to the diagnosis of pCP. After the surgery, her visual function improved and follow-up Magnetic resonance imaging at 18 months postoperatively showed no apparent recurrence. The presence of condensed-milk-like content suggests a likelihood of RCC indicating that aggressive resection may not be necessary. In contrast, the existence of fish-egg-like structures suggests pCP and requires careful follow-up.

2.
Am J Physiol Gastrointest Liver Physiol ; 326(4): G438-G459, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38193195

RESUMO

The calcium-sensing receptor (CaSR), a G protein-coupled receptor, regulates Ca2+ concentration in plasma by regulating parathyroid hormone secretion. In other tissues, it is reported to play roles in cellular differentiation and migration and in secretion and absorption. We reported previously that CaSR can be conditionally deleted in the mouse esophagus. This conditional knockout (KO) (EsoCaSR-/-) model showed a significant reduction in the levels of adherens and tight junction proteins and had a marked buildup of bacteria on the luminal esophageal surface. To further examine the role of CaSR, we used RNA sequencing to determine gene expression profiles in esophageal epithelia of control and EsoCaSR-/-mice RNA Seq data indicated upregulation of gene sets involved in DNA replication and cell cycle in EsoCaSR-/-. This is accompanied by the downregulation of gene sets involved in the innate immune response and protein homeostasis including peptide elongation and protein trafficking. Ingenuity pathway analysis (IPA) demonstrated that these genes are mapped to important biological networks including calcium and Ras homologus A (RhoA) signaling pathways. To further explore the bacterial buildup in EsoCaSR-/- esophageal tissue, 16S sequencing of the mucosal-associated bacterial microbiome was performed. Three bacterial species, g_Rodentibacter, s_Rodentibacter_unclassified, and s_Lactobacillus_hilgardi were significantly increased in EsoCaSR-/-. Furthermore, metagenomic analysis of 16S sequences indicated that pathways related to oxidative phosphorylation and metabolism were downregulated in EsoCaSR-/- tissues. These data demonstrate that CaSR impacts major pathways of cell proliferation, differentiation, cell cycle, and innate immune response in esophageal epithelium. The disruption of these pathways causes inflammation and significant modifications of the microbiome.NEW & NOTEWORTHY Calcium-sensing receptor (CaSR) plays a significant role in maintaining the barrier function of esophageal epithelium. Using RNA sequencing, we show that conditional deletion of CaSR from mouse esophagus causes upregulation of genes involved in DNA replication and cell cycle and downregulation of genes involved in the innate immune response, protein translation, and cellular protein synthesis. Pathway analysis shows disruption of signaling pathways of calcium and actin cytoskeleton. These changes caused inflammation and esophageal dysbiosis.


Assuntos
Cálcio , Microbiota , Animais , Camundongos , Cálcio/metabolismo , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismo , Esôfago/metabolismo , Inflamação , Expressão Gênica
3.
Dev Biol ; 492: 59-70, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36179879

RESUMO

The IRE1α-XBP1s signaling branch of the unfolded protein response is a well-characterized survival pathway that allows cells to adapt to and resolve endoplasmic reticulum stress. Recent data has broadened our understanding of IRE1α-XBP1s signaling beyond a stress response and revealed a physiological mechanism required for the differentiation and maturation of a wide variety of cell types. Here we provide evidence that the IRE1α-XBP1s signaling pathway is required for the proliferation and maturation of basal keratinocytes in the mouse tongue and esophageal epithelium. Mice with conditional targeted deletion of either Ire1α or Xbp1 in keratin 14 expressing basal keratinocytes displayed severe thinning of the lingual and esophageal mucosa that rendered them unable to eat. In IRE1α null epithelium harvested at an earlier timepoint, genes regulating cell proliferation, cell-cell adhesion, and keratinization were significantly downregulated; indirect immunofluorescence revealed fewer proliferating basal keratinocytes, downregulation of E-cadherin, and thinning of the loricrin-positive granular and cornified layers. The number of Tp63-positive basal keratinocytes was reduced in the absence of IRE1α, and expression of the Wnt pathway transcription factor LEF1, which is required for the proliferation of lingual transit amplifying cells, was also significantly downregulated at the transcript and protein level. Together these results reveal an essential role for IRE1α-XBP1s in the maintenance of the stratified squamous epithelial tissue of the tongue and esophagus.


Assuntos
Endorribonucleases , Proteínas Serina-Treonina Quinases , Camundongos , Animais , Endorribonucleases/genética , Endorribonucleases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Resposta a Proteínas não Dobradas/genética , Estresse do Retículo Endoplasmático/genética , Esôfago , Língua/metabolismo
4.
Dev Biol ; 485: 9-23, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35227671

RESUMO

Transforming Growth Factor Beta 1 (TGFß1) is a multifunctional cytokine that regulates proliferation, apoptosis, and epithelial-mesenchymal transition of epithelial cells. While its role in cancer is well studied, less is known about TGFß1 and regulation of epithelial development. To address this, we deleted TGFß1 in basal keratinocytes of stratified squamous epithelia. Newborn mice with a homozygous TGFß1 deletion had significant defects in proliferation and differentiation of the epidermis and oral mucosa, and died shortly after birth. Hair follicles were sparse in TGFß1 depleted skin and had delayed development. Additionally, the Wnt pathway transcription factor LEF1 was reduced in hair follicle bulbs and nearly absent from the basal epithelial layer. Hemizygous knockout mice survived to adulthood but were runted and had sparse coats. The skin of these mice had irregular hair follicle morphology and aberrant hair cycle progression, as well as abnormally high melanin expression and delayed melanocyte migration. In contrast to newborn TGFß1 null mice, the epidermis was hyperproliferative, acanthotic and inflamed. Expression of p63, a master regulator of stratified epithelial identity, proliferation and differentiation, was reduced in TGFß1 null newborn epidermis but expanded in the postnatal acanthotic epidermis of TGFß1 hemizygous mice. Thus, TGFß1 is both essential and haploinsufficient with context dependent roles in stratified squamous epithelial development and homeostasis.


Assuntos
Carcinoma de Células Escamosas , Queratinócitos , Animais , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Epiderme/metabolismo , Epitélio/metabolismo , Folículo Piloso , Melanócitos , Camundongos
5.
Diseases ; 11(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36648870

RESUMO

Background: The normal tissue structure of the respiratory system is necessary to provide adequate protection of the airways and lungs. Prolonged exposure to trigger factors can result in adaptive mechanism activation and lead to the development of chronic pulmonary diseases or even dysplastic changes. Materials and methods: Respiratory system material with a pseudostratified ciliated epithelium was obtained from 12 patients (aged 16 to 95), and material with a stratified squamosa epithelium was obtained from six patients (aged 23 to 93). Routine staining was performed, and an immunohistochemistry was conducted for MUC-2, MUC-6, NAPE-PLD, IL-6 and IL-13. Results: Inflammatory processes were not detected in any of the specimens. A number of correlations were identified, with the most important being a strong positive correlation for IL-13 between the alveolar epithelium and alveolar macrophages and a strong positive correlation for IL-6 between the alveolar epithelium and alveolar macrophages in the stratified squamous epithelium group. We also detected a statistically significant difference in IL-6 in alveolar macrophages. Conclusions: There were no signs of dysplastic changes in either group. Increased secretion of IL-13 in the stratified squamous epithelium group shows its involvement in metaplastic changes in the bronchial epithelium. The secretion of atypical factors by hyaline cartilage demonstrates its plasticity and adaptability.

6.
Toxicol Rep ; 8: 920-937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996505

RESUMO

The larynx is an essential organ in the respiratory tract and necessary for airway protection, respiration, and phonation. Cigarette smoking is a significant risk factor associated with benign and malignant laryngeal diseases. Despite this association, the underlying mechanisms by which cigarette smoke (CS) drives disease development are not well elucidated. In the current study, we developed a short-term murine whole body inhalation model to evaluate the first CS-induced cellular responses in the glottic [i.e. vocal fold (VF)] and subglottic regions of the larynx. Specifically, we investigated epithelial cell proliferation, cell death, surface topography, and mucus production, at various time points (1 day, 5 days, 10 days) after ∼ 2 h exposure to 3R4F cigarettes (Delivered dose: 5.6968 mg/kg per cigarette) and following cessation for 5 days after a 5 day CS exposure (CSE). CSE elevated levels of BrdU labeled proliferative cells and p63 labeled epithelial basal cells on day 1 in the VF. CSE increased proliferative cells in the subglottis at days 5, 10 and following cessation in the subglottis. Cleaved caspase-3 apoptotic activity was absent in VF at all time points and increased at day 1 in the subglottis. Evaluation of the VF surface by scanning electron microscopy (SEM) revealed significant epithelial microprojection damage at day 10 and early signs of necrosis at days 5 and 10 post-CSE. SEM visualizations additionally indicated the presence of deformed cilia at days 5 and 10 after CSE and post-cessation in the respiratory epithelium lined subglottis. In terms of mucin content, the impact of short-term CSE was observed only at day 10, with decreasing acidic mucin levels and increasing neutral mucin levels. Overall, these findings reveal regional differences in murine laryngeal cellular responses following short-term CSE and provide insight into potential mechanisms underlying CS-induced laryngeal disease development.

7.
Auris Nasus Larynx ; 48(4): 704-709, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33261983

RESUMO

OBJECTIVES: The human adult vocal fold mucosa, especially, superficial layer of the lamina propria (Reinke's space) has attracted notice as an important vibrating structure. However, fine structures of the stratified squamous epithelium of the human adult vocal fold, which is another histological component of the mucosa, remain enigmatic. METHODS: Three normal human adult vocal folds and epiglottises and three newborn vocal folds were investigated. Observations using transmission electron microscopy and light microscopy including immunohistochemistry were performed. RESULTS: The most obvious feature of the epithelium of the human adult vocal folds was that the intercellular spaces between adjacent epithelial cells were large (984 ± 186 nm) compared with the stratified squamous epithelium of the human adult epiglottis and the human newborn vocal fold. Even though intercellular spaces between adjacent epithelial cells of the human adult vocal fold were large, desmosomes at the junctions of two adjacent epithelial cells made firm intercellular adhesion. Tonofilaments composed of the bundles of intermediate filaments anchored to the desmosomes. Desmosomes formed a continuous cytoskeletal network throughout the epithelial cells and epithelium of the human adult vocal fold. In addition, a great deal of E-cadherin (adhesive glycoprotein) was present between epithelial cells especially the lower half of the stratified squamous epithelium of the human adult vocal fold. CONCLUSIONS: From the functional morphological point of view, stratified squamous epithelium of the human adult vocal fold seems to form a structural framework of tensile strength with pliability suitable structure for vibration.


Assuntos
Células Epiteliais/ultraestrutura , Prega Vocal/citologia , Adulto , Caderinas/análise , Células Epiteliais/química , Epitélio/anatomia & histologia , Epitélio/química , Epitélio/fisiologia , Humanos , Imuno-Histoquímica , Recém-Nascido , Microscopia Eletrônica de Transmissão e Varredura , Prega Vocal/ultraestrutura
8.
Am J Physiol Gastrointest Liver Physiol ; 318(1): G144-G161, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31709833

RESUMO

Calcium-sensing receptor (CaSR) is the molecular sensor by which cells respond to small changes in extracellular Ca2+ concentrations. CaSR has been reported to play a role in glandular and fluid secretion in the gastrointestinal tract and to regulate differentiation and proliferation of skin keratinocytes. CaSR is present in the esophageal epithelium, but its role in this tissue has not been defined. We deleted CaSR in the mouse esophagus by generating keratin 5 CreER;CaSRFlox+/+compound mutants, in which loxP sites flank exon 7 of CaSR gene. Recombination was initiated with multiple tamoxifen injections, and we demonstrated exon 7 deletion by PCR analysis of genomic DNA. Quantitative real-time PCR and Western blot analyses showed a significant reduction in CaSR mRNA and protein expression in the knockout mice (EsoCaSR-/-) as compared with control mice. Microscopic examination of EsoCaSR-/- esophageal tissues showed morphological changes including elongation of the rete pegs, abnormal keratinization and stratification, and bacterial buildup on the luminal epithelial surface. Western analysis revealed a significant reduction in levels of adherens junction proteins E-cadherin and ß catenin and tight junction protein claudin-1, 4, and 5. Levels of small GTPase proteins Rac/Cdc42, involved in actin remodeling, were also reduced. Ussing chamber experiments showed a significantly lower transepithelial resistance in knockout (KO) tissues. In addition, luminal-to-serosal-fluorescein dextran (4 kDa) flux was higher in KO tissues. Our data indicate that CaSR plays a role in regulating keratinization and cell-cell junctional complexes and is therefore important for the maintenance of the barrier function of the esophagus.NEW & NOTEWORTHY The esophageal stratified squamous epithelium maintains its integrity by continuous proliferation and differentiation of the basal cells. Here, we demonstrate that deletion of the calcium-sensing receptor, a G protein-coupled receptor, from the basal cells disrupts the structure and barrier properties of the epithelium.


Assuntos
Mucosa Esofágica/metabolismo , Receptores de Detecção de Cálcio/deficiência , Junções Aderentes/metabolismo , Junções Aderentes/patologia , Animais , Caderinas/metabolismo , Diferenciação Celular , Proliferação de Células , Claudinas/metabolismo , Impedância Elétrica , Mucosa Esofágica/microbiologia , Mucosa Esofágica/patologia , Feminino , Deleção de Genes , Masculino , Camundongos Knockout , Permeabilidade , Receptores de Detecção de Cálcio/genética , Transdução de Sinais , Junções Íntimas/metabolismo , Junções Íntimas/patologia , beta Catenina/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo
9.
J Biophotonics ; 12(9): e201900073, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31100192

RESUMO

Imaging nuclei of keratinocytes in the stratified squamous epithelium has been a subject of intense research since nucleus associated cellular atypia is the key criteria for the screening and diagnosis of epithelial cancers and their precursors. However, keratinocyte nuclei have been reported to be either low scattering or high scattering, so that these inconsistent reports might have led to misinterpretations of optical images, and more importantly, hindered the establishment of optical diagnostic criteria. We disclose that they are generally low scattering in the core using Micro-optical coherence tomography (µOCT) of 1.28-µm axial resolution in vivo; those previously reported "high scattering" or "bright" signals from nuclei are likely from the nucleocytoplasmic boundary, and the low-scattering nuclear cores were missed possibly due to insufficient axial resolutions (~4µm). It is further demonstrated that the high scattering signals may be associated with flattening of nuclei and cytoplasmic glycogen accumulation, which are valuable cytologic hallmarks of cell maturation.


Assuntos
Carcinoma de Células Escamosas/patologia , Núcleo Celular/patologia , Epitélio/patologia , Tomografia de Coerência Óptica , Animais , Carcinoma de Células Escamosas/diagnóstico por imagem , Núcleo Celular/metabolismo , Colo do Útero/patologia , Citoplasma/metabolismo , Epiderme/metabolismo , Epitélio/diagnóstico por imagem , Esôfago/patologia , Feminino , Glicogênio/química , Humanos , Técnicas In Vitro , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinas/química , Luz , Mucosa Bucal/patologia , Ratos , Ratos Sprague-Dawley , Espalhamento de Radiação , Suínos , Microtomografia por Raio-X
10.
Development ; 143(10): 1674-87, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26989177

RESUMO

The skin is a squamous epithelium that is continuously renewed by a population of basal layer stem/progenitor cells and can heal wounds. Here, we show that the transcription regulators YAP and TAZ localise to the nucleus in the basal layer of skin and are elevated upon wound healing. Skin-specific deletion of both YAP and TAZ in adult mice slows proliferation of basal layer cells, leads to hair loss and impairs regeneration after wounding. Contact with the basal extracellular matrix and consequent integrin-Src signalling is a key determinant of the nuclear localisation of YAP/TAZ in basal layer cells and in skin tumours. Contact with the basement membrane is lost in differentiating daughter cells, where YAP and TAZ become mostly cytoplasmic. In other types of squamous epithelia and squamous cell carcinomas, a similar control mechanism is present. By contrast, columnar epithelia differentiate an apical domain that recruits CRB3, Merlin (also known as NF2), KIBRA (also known as WWC1) and SAV1 to induce Hippo signalling and retain YAP/TAZ in the cytoplasm despite contact with the basal layer extracellular matrix. When columnar epithelial tumours lose their apical domain and become invasive, YAP/TAZ becomes nuclear and tumour growth becomes sensitive to the Src inhibitor Dasatinib.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Homeostase , Integrinas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais , Pele/metabolismo , Animais , Proteínas de Ciclo Celular , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Dasatinibe/farmacologia , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Receptores ErbB/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Camundongos , Neoplasias de Células Escamosas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/patologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Cicatrização/efeitos dos fármacos , Proteínas de Sinalização YAP , Quinases da Família src/metabolismo
11.
Cell Tissue Res ; 363(2): 479-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26299200

RESUMO

Beta-defensin 103 (DEFB103) shares little homology with 8 other members of the bovine beta-defensin family and in other species DEFB103 protein has diverse functions, including antimicrobial activity, a chemoattractant for dendritic cells, enhancing epithelial wound repair and regulating hair colour. Expression of the bovine DEFB103 gene was surveyed in 27 tissues and transcript was most abundant in tissues with stratified squamous epithelium. Oral cavity epithelial tissues and nictitating membrane consistently expressed high levels of DEFB103 gene transcript. An age-dependent decrease (P < 0.05) in DEFB103 gene expression was only observed for buccal epithelium when comparing healthy 10- to 14-day-old and 10- to 12-month-old calves. A bovine herpesvirus-1 respiratory infection did, however, significantly (P < 0.05) up-regulate DEFB103 gene expression in the buccal epithelium of 6- to 8-month-old calves. Finally, DEFB103 transcript was low in lymph nodes draining the skin and at the limit of detection in other internal organs such as lung, intestine and kidney. Affinity-purified rabbit antisera to bovine DEFB103 was used to identify cells expressing DEFB103 protein within tissues with stratified squamous epitheliums. DEFB103 protein was most abundant in basal epithelial cells and was present in these cells prior to birth. Beta-defensins have been identified as regulators of dendritic cell (DC) chemokine responses and we observed a close association between DCs and epithelial cells expressing DEFB103 in both the fetus and newborn calf. In conclusion, bovine DEFB103 gene expression is most abundant in stratified squamous epithelium with DEFB103 protein localised to basal epithelial cells. These observations are consistent with proposed roles for DEFB103 in DC recruitment and repair of stratified squamous epithelium.


Assuntos
Envelhecimento/genética , Regulação da Expressão Gênica no Desenvolvimento , Especificidade de Órgãos/genética , beta-Defensinas/genética , beta-Defensinas/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Bovinos , Feminino , Perfilação da Expressão Gênica , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Alinhamento de Sequência , Viroses/genética , beta-Defensinas/química
12.
J Clin Diagn Res ; 9(10): ZD08-10, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26557626

RESUMO

Keratoacanthoma is a benign lesion usually presenting as a solitary, dome shaped nodule with a central crater filled with keratin. It frequently occurs on the sun exposed areas of the skin. Keratoacanthoma can be difficult to differentiate from oral squamous cell carcinoma both clinically and microscopically. A case of keratoacanthoma involving the upper lip in a 51-year-old male is reported presenting as an exophytic growth that resolved after excisional biopsy.

13.
Physiol Rep ; 3(11)2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26603452

RESUMO

The calcium-sensing receptor (CaSR), a G-protein-coupled receptor, plays a role in glandular and fluid secretion in the gastrointestinal tract, and regulates differentiation and proliferation of epithelial cells. We examined the expression of CaSR in normal and pathological conditions of human esophagus and investigated the effect of a CaSR agonist, cinacalcet (CCT), and antagonist, calhex (CHX), on cell growth and cell-cell junctional proteins in primary cultures of porcine stratified squamous esophageal epithelium. We used immunohistochemistry and Western analysis to monitor expression of CaSR and cell-cell adhesion molecules, and MTT assay to monitor cell proliferation in cultured esophageal cells. CCT treatment significantly reduced proliferation, changed the cell shape from polygonal to spindle-like, and caused redistribution of E-cadherin and ß-catenin from the cell membrane to the cytoplasm. Furthermore, it reduced expression of ß-catenin by 35% (P < 0.02) and increased expression of a proteolysis cleavage fragment of E-cadherin, Ecad/CFT2, by 2.3 folds (P < 0.01). On the other hand, CHX treatment enhanced cell proliferation by 27% (P < 0.01), increased the expression of p120-catenin by 24% (P < 0.04), and of Rho, a GTPase involved in cytoskeleton remodeling, by 18% (P < 0.03). In conclusion, CaSR is expressed in normal esophagus as well as in Barrett's, esophageal adenocarcinoma, squamous cell carcinoma, and eosinophilic esophagitis. Long-term activation of CaSR with CCT disrupted the cadherin-catenin complex, induced cytoskeletal remodeling, actin fiber formation, and redistribution of CaSR to the nuclear area. These changes indicate a significant and complex role of CaSR in epithelial remodeling and barrier function of esophageal cells.

14.
Biochem Biophys Res Commun ; 438(1): 54-60, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23867827

RESUMO

The interaction of B7 family members with appropriate receptors is essential for an effective T cell response. CD80 and CD86 are the principal co-stimulatory molecules of this family and they are mainly expressed on professional antigen presenting cells (APCs), but also on several non-lymphoid cells. CD86 is constitutively expressed in keratinocytes from the spinous layer of normal cervical epithelium. However, the mechanisms that control the expression of this gene in epithelial cells remain unknown. We analyzed the DNA methylation status of the CD86 promoter and a CpG island located in the upstream intergenic region in keratinocyte-derived cell lines. In those cell lines where CD86 is expressed, a high degree of methylation in the CpG island was observed. However, a CpG dinucleotide within the cAMP response element (CRE) in the promoter region was consistently unmethylated and associated to the transcription factor CREB, as demonstrated by ChIP assays. The opposite methylation pattern was observed in cell lines where CD86 is not expressed, affecting also the binding of CREB. The analysis of the DNA methylation pattern of this gene in cells from the spinous and basal layers of normal cervical epithelium showed a similar profile to that observed in cell lines with and without expression of CD86 respectively. Our results indicate that the methylation pattern in the CD86 promoter and CpG island is closely related to the expression of this co-stimulatory molecule in keratinocytes.


Assuntos
Antígeno B7-2/genética , Ilhas de CpG/genética , Metilação de DNA/genética , Regulação da Expressão Gênica/genética , Queratinócitos/fisiologia , Regiões Promotoras Genéticas/genética , Linhagem Celular , Humanos
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