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1.
Am J Transplant ; 14(12): 2887-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25359127

RESUMO

A 15-year-old boy with a posterior urethral valve received a deceased donor kidney transplant (KT) in March 2011. Basiliximab induction followed by tacrolimus-based triple medication was used as immunosuppression. Eleven months after KT, the graft function deteriorated and the biopsy demonstrated interstitial nephritis suggestive of acute rejection. BK polyomavirus (BKPyV) surveillance in urine and plasma was negative. The patient received methylprednisolone pulses and anti-thymocyte globulin. Immunohistochemistry was positive for simian virus 40 (SV40) large T-antigen (LTag) in the biopsies, and quantitative polymerase chain reaction for JC polyomavirus (JCPyV) indicated high viral loads in urine and borderline levels in plasma. Immunosuppression was reduced and follow-up biopsies showed tubular atrophy and interstitial fibrosis. Two years after KT, antibody-mediated rejection resulted in graft loss and return to hemodialysis. Retrospective serologic work-up indicated a primary JCPyV infection with seroconversion first for IgM, followed by IgG, but no indication of BKPyV infection. In the SV40 LTag positive biopsies, JCPyV deoxyribonucleic acid (DNA) with archetype noncoding control region was detected, while BKPyV DNA was undetectable. To the best of our knowledge, this is the first reported case of primary JCPyV infection as the cause of PyV-associated nephropathy in KT.


Assuntos
Rejeição de Enxerto/etiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Nefrite Intersticial/virologia , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Adolescente , DNA Viral/genética , Rejeição de Enxerto/diagnóstico , Humanos , Imunossupressores/uso terapêutico , Vírus JC/patogenicidade , Falência Renal Crônica/complicações , Falência Renal Crônica/virologia , Masculino , Nefrite Intersticial/diagnóstico , Infecções por Polyomavirus/complicações , Complicações Pós-Operatórias , Prognóstico , Diálise Renal , Infecções Tumorais por Vírus/complicações , Carga Viral
2.
Eur J Clin Microbiol Infect Dis ; 31(8): 1783-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22179415

RESUMO

Resins (rosin, pitch) are natural products of the coniferous trees and are antimicrobial against a wide range of microbes. The antifungal effectiveness of resin, purified from Norway spruce (Picea abies), was studied against human pathogenic fungi and yeasts with the agar plate diffusion tests and electron microscopy (EM). The fungistatic effect of these resin mixtures (resin salves) was tested against a set of Candida yeasts, dermatophytes, and opportunistic fungi. Transmission and scanning EM was done from samples of fungi (Trichophyton mentagrophytes). In agar diffusion tests, the resin was strongly antifungal against all dermatophytes tested, e.g., against all fungi of the genus Trichophyton, but it was not antifungal against the Candida yeasts or against the opportunistic fungi tested. According to EM, resin caused damages in the cell hyphae and cell wall structures. We conclude that, in the agar plate diffusion test, coniferous resins are strongly fungistatic against the dermatophytic fungi only.


Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Picea/química , Resinas Vegetais/farmacologia , Ágar , Antifúngicos/isolamento & purificação , Parede Celular/efeitos dos fármacos , Meios de Cultura/química , Fungos/crescimento & desenvolvimento , Fungos/ultraestrutura , Humanos , Hifas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Noruega , Resinas Vegetais/isolamento & purificação
3.
J Wound Care ; 19(3): 123-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20559190

RESUMO

A vast range of dressings can be used on pressure ulcers, but despite this and the high expense often involved, there is no gold standard for the local treatment of these wounds. This literature review therefore set out to examine the evidence.


Assuntos
Bandagens , Úlcera por Pressão/terapia , Curativos Hidrocoloides , Terapia Biológica/métodos , Fármacos Dermatológicos/uso terapêutico , Medicina Baseada em Evidências , Humanos , Úlcera por Pressão/patologia
4.
Br J Dermatol ; 158(5): 1055-62, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18284391

RESUMO

BACKGROUND: Resin salve of the Norway spruce (Picea abies) has been used in folk medicine to heal wounds and infections. OBJECTIVES: To study its clinical effectiveness in the treatment of pressure ulcers of the skin. METHODS: A prospective, randomized, controlled multicentre trial involving 37 patients with grade II-IV pressure ulcers in 11 primary care hospitals was carried out between 2005 and 2007. The ulcers were randomly allocated to receive either resin salve or sodium carboxymethylcellulose hydrocolloid polymer treatment. The inclusion criterion was grade II-IV pressure ulcer. Exclusion criteria were a life expectancy of less than 6 months or a malignant disease. The primary outcome measure was complete healing of the ulcer within 6 months. Secondary outcome measures were partial healing of the ulcer, and successful eradication of bacterial strains cultured from the ulcers at study entry. RESULTS: Thirteen patients of the resin group and nine patients of the control group completed the 6-month trial. All ulcers healed in 12 of the 13 patients (92%) in the resin group and in four of the nine patients (44%) in the control group (P=0.003; power 73%). Complete healing of the ulcers over time was significantly more common in the resin group than in the control group (P=0.013). Bacterial cultures from the ulcer area more often became negative within 1 month in the resin group. CONCLUSIONS: Traditional resin salve is significantly more effective in the treatment of infected and noninfected severe pressure ulcers than cellulose polymer gauzes.


Assuntos
Antibacterianos/uso terapêutico , Fitoterapia , Picea , Úlcera por Pressão/tratamento farmacológico , Resinas Vegetais/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Preparações de Plantas/uso terapêutico , Úlcera por Pressão/microbiologia , Estudos Prospectivos , Cicatrização
5.
APMIS ; 115(4): 335-40, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17504300

RESUMO

Resin salve made from Norway spruce (Picea abies) is traditionally used in folk medicine to heal skin ulcers and infected wounds. Its antimicrobial properties were studied against certain human bacteria important in infected skin wounds. The sensitivity of the resin against Gram-positive and Gram-negative bacteria was studied in vitro by methods that are routinely used in microbiology laboratories. The resin salve exhibited a bacteriostatic effect against all tested Gram-positive bacteria but only against Proteus vulgaris of the Gram-negative bacteria. Interestingly, the resin inhibited the growth of bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE), both on agar plates and in culture media. The study demonstrated antimicrobial activity of the resin salve and provided objective evidence of its antimicrobial properties. It gives some explanations why the traditional use of home-made resin salve from Norway spruce is experienced as being effective in the treatment of infected skin ulcers.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Picea/química , Resinas Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Resinas Vegetais/isolamento & purificação
7.
Dig Dis Sci ; 49(4): 653-61, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15185874

RESUMO

Several matrix metalloproteinases (MMPs) have been implicated in intestinal inflammation, mucosal wound healing, and cancer progression. The purpose of this study was to examine the cellular location and putative function of MMP-19, MMP-26 (matrilysin-2), and MMP-28 (epilysin), in normal, inflammatory, and malignant conditions of the intestine. Peroperative tissue specimens from patients with ulcerative colitis (UC) (n = 16) and archival tissue samples of ischemic colitis (n = 9), Crohn's disease (n = 7), UC (n = 8), colon cancer (n = 20), and healthy intestine (n = 5) were examined using immunohistochemical analyses with polyclonal antibodies. Unlike many classical MMPs, MMP-19, MMP-26, and MMP-28 were all expressed in normal intestine. In inflammatory bowel disease (IBD), MMP- 19 was expressed in nonmigrating enterocytes and shedding epithelium. MMP-26 was detected in migrating enterocytes, unlike MMP-28. In colon carcinomas, MMP-19 and MMP-28 expression was downregulated in tumor epithelium. Staining for MMP-26 revealed a meshwork-like pattern between cancer islets, which was absent from most dedifferentiated areas. Our results suggest that MMP-19 is involved in epithelial proliferation and MMP-26 in enterocyte migration, while MMP-28 expression is not associated with inflammatory and destructive changes seen in IBD. In contrast to many previously characterized MMPs, MMP-19 and MMP-28 are downregulated during malignant transformation of the colon and may play a prominent role in tissue homeostasis.


Assuntos
Colite Ulcerativa/patologia , Neoplasias do Colo/patologia , Doença de Crohn/patologia , Metaloproteinases da Matriz/análise , Metaloendopeptidases/análise , Biomarcadores/análise , Movimento Celular , Estudos de Coortes , Colite Ulcerativa/metabolismo , Neoplasias do Colo/metabolismo , Doença de Crohn/metabolismo , Técnicas de Cultura , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinases da Matriz Secretadas , Probabilidade , Prognóstico , Valores de Referência , Sensibilidade e Especificidade
8.
Int J Cancer ; 94(6): 763-7, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11745475

RESUMO

The basement membrane (BM) separates epithelial elements from the surrounding stroma. BM is dynamic in regulation of epithelial cells differentiation as well as their organization into 3-dimensional tissues. In these functions, among the molecules of the BM, laminins are especially dynamic. Laminins are distributed in a spatially and temporally regulated manner in various epithelial tissues. Various changes in the laminin distribution accompany the malignant transformation of epithelia. The role of the BM and laminins in the progression of carcinomas is not well understood. The BM has been suggested to act as a mechanical barrier against carcinoma cell invasion. BM laminins may play an active role in regulating the migration and proliferation of the carcinoma cells. Laminin isoform laminin-5 expression is typical for some invasive carcinomas and it may act as a ligand for invading carcinoma cells. Neoexpression of laminin-5 has also been associated to proliferative activity of the carcinoma cells. Integrins alpha(3)beta(1) and alpha(6)beta(4) are probable cell surface receptors acting with laminin-5 in the regulation of carcoma cell invasion and proliferation.


Assuntos
Moléculas de Adesão Celular/fisiologia , Neoplasias/patologia , Membrana Basal/química , Divisão Celular , Humanos , Integrinas/fisiologia , Invasividade Neoplásica , Calinina
9.
Gene ; 275(1): 185-94, 2001 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-11574168

RESUMO

Epilysin (MMP-28) is a recently cloned member of the matrix metalloproteinase family (Lohi et al., J. Biol. Chem. 276 (2001) 10134). It is expressed at highest levels in the skin by basal and suprabasal keratinocytes, and in testis by developing germ cells. To characterize the epilysin promoter, we isolated a 3.0 kb fragment of human genomic DNA containing 5'-flanking sequence of the epilysin gene, and a corresponding 660 bp fragment from the mouse. The 5'-flanking sequences contain no typical TATA-boxes or CCAAT sequences close to the translation initiation sites. RNase protection assay revealed that two transcription start sites are utilized in the human epilysin gene, situated 210 and 230 bp upstream from the translation start site. The promoter contains a GT-box, situated 300 bp upstream from the translation start site, with homology to the consensus binding site for transcription factors of the Sp family. This site is perfectly conserved between the human and mouse promoters. For reporter gene assays a series of constructs with fragments of increasing length of the epilysin promoter were coupled to the firefly luciferase gene. Reporter gene assays indicated that deletion or mutation of the GT-box dramatically reduces the transcriptional activity both in keratinocytes and in spermatogonia. Gel mobility shift assays showed that several nuclear proteins bind specifically to this sequence. Supershift assays with antibodies specific for members of the Sp family identified Sp1 and Sp3 as components of these protein/DNA complexes and hence as possible regulators of the epilysin gene. Our results indicate that the epilysin promoter has distinctive structural and functional features, which may control the unique expression and regulation patterns of the epilysin gene.


Assuntos
Metaloproteinases da Matriz/genética , Regiões Promotoras Genéticas/genética , Animais , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Linhagem Celular Transformada , DNA/química , DNA/genética , DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Luciferases/genética , Luciferases/metabolismo , Metaloproteinases da Matriz Secretadas , Camundongos , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/metabolismo , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Sítio de Iniciação de Transcrição
10.
Scand J Gastroenterol ; 36(6): 630-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11424322

RESUMO

BACKGROUND: Certain lactobacilli reduce the severity of experimental colitis. The aim of this study was to compare the effects of a human strain Lactobacillus rhamnosus GG and a rat strain Lactobacillus reuteri R2LC on acetic acid-induced colitis in rats. METHODS: Lactobacillus rhamnosus GG, Lactobacillus reuteri R2LC or sulphasalazine were given orally to the rats. Colitis was assessed 72 h after induction with acetic acid. RESULTS: Lactobacillus reuteri R2LC significantly antagonized body weight loss caused by inflammation compared with Lactobacillus rhamnosus GG and sulphasalazine, and oedema formation in the colon compared with sulphasalazine. Lactobacillus reuteri R2LC reduced the median value of macroscopic ulceration and the protein content of inducible nitric oxide synthase by 50% and the median of the protein content of inducible cyclooxygenase by 30% compared with that of the colitis control group, and Lactobacillus rhamnosus GG reduced the median of inducible nitric oxide protein content by 40% and increased the median of inducible cyclooxygenase protein content by 30% compared with the median value of the colitis control group, but these differences were not statistically significant. CONCLUSIONS: The rat strain Lactobacillus reuteri R2LC, but not the human strain Lactobacillus rhamnosus GG, is of benefit in reducing the severity of acetic acid-induced colitis in rats. These results suggest that it is not the total amount of Lactobacillus but the particular species or strain of Lactobacillus that is important in attenuating experimental colitis.


Assuntos
Colite/induzido quimicamente , Lactobacillus , Ácido Acético , Animais , Peso Corporal , Colite/microbiologia , Colo/enzimologia , Ciclo-Oxigenase 2 , Ingestão de Alimentos , Humanos , Isoenzimas/metabolismo , Lactobacillus/classificação , Masculino , Proteínas de Membrana , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Peroxidases/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos
11.
J Biol Chem ; 276(31): 29257-67, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11359770

RESUMO

Using an in vitro model of keratinocyte activation by the extracellular matrix following injury, we have identified epsin 3, a novel protein closely related to, but distinct from previously described epsins. Epsin 3 contains a domain structure common to this gene family, yet demonstrates novel differences in its regulation and pattern of expression. Epsin 3 mRNA and protein were undetectable in keratinocytes isolated from unwounded skin, but induced in cells following contact with fibrillar type I collagen. The native triple helical structure of collagen was required to mediate this response as cells failed to express epsin 3 when plated on gelatin. Consistent with the reported function of other epsins, epsin 3 was evident in keratinocytes as punctate vesicles throughout the cytoplasm that partially co-localized with clathrin. In addition, epsin 3 exhibited nuclear accumulation when nuclear export was inhibited. In contrast to other known epsins, epsin 3 was restricted to keratinocytes migrating across collagen and down-regulated following cell differentiation, suggesting that expression was spatially and temporally regulated. Indeed, epsin 3 was localized specifically to migrating keratinocytes in cutaneous wounds, but not found in intact skin. Intriguingly, Northern hybridization and reverse transcriptase-polymerase chain reaction experiments indicated that epsin 3 expression was restricted to epithelial wounds or pathologies exhibiting altered cell-extracellular matrix interactions. Thus, we have identified a novel type I collagen-induced epsin that demonstrates structural and behavioral similarity to this gene family, yet exhibits restricted and regulated expression, suggesting that epsin 3 may serve an important function in activated epithelial cells during tissue morphogenesis.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Colágeno/fisiologia , Células Epiteliais/fisiologia , Matriz Extracelular/fisiologia , Queratinócitos/fisiologia , Transcrição Gênica , Proteínas de Transporte Vesicular , Ferimentos e Lesões/fisiopatologia , Proteínas Adaptadoras de Transporte Vesicular , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/química , Núcleo Celular/metabolismo , Células Cultivadas , Colágeno/farmacologia , Éxons , Regulação da Expressão Gênica , Humanos , Íntrons , Queratinócitos/citologia , Camundongos , Dados de Sequência Molecular , Neuropeptídeos/química , Especificidade de Órgãos , Filogenia , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fenômenos Fisiológicos da Pele , Ferimentos e Lesões/genética , Xenopus
12.
Br J Cancer ; 84(5): 659-69, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11237387

RESUMO

Co-expression of several members of the matrix metalloproteinase (MMP) family is characteristic of human malignant tumours. To investigate the role of stromelysin-2 (MMP-10) in growth and invasion of skin tumours, we studied cutaneous carcinomas with high metastatic capacity (squamous cell carcinomas, SCCs), only locally destructive tumours (basal cell carcinomas, BCCs) and pre-malignant lesions (Bowen's disease and actinic keratosis) using in situ hybridization. Expression of MMP-10 was compared with that of stromelysin-1 (MMP-3) and of MT1-MMP, the expression of which has been shown to correlate with tumour invasiveness. MMP-10 was expressed in 13/21 SSCs and 11/19 BCCs only in epithelial laminin-5 positive cancer cells, while premalignant lesions were entirely negative. MT1-MMP mRNA was detected in 19/21 SCCs both in epithelial cancer cells and stromal fibroblasts and in 14/18 BCCs only in fibroblasts. The level of MMP-10 was upregulated in a cutaneous SCC cell line (UT-SCC-7) by transforming growth factor-alpha and keratinocyte growth factor, and by interferon-gamma in combination with transforming growth factor-beta1 and tumour necrosis factor-alpha both in UT-SCC-7 and HaCaT cells. Our results show that MMP-10 expression does not correlate with the invasive behaviour of tumours as assessed by their histology and MT1-MMP expression, but may be induced by the wound healing and inflammatory matrix remodelling events associated with skin tumours.


Assuntos
Carcinoma Basocelular/genética , Carcinoma de Células Escamosas/genética , Metaloendopeptidases/genética , Neoplasias Cutâneas/genética , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Moléculas de Adesão Celular/metabolismo , Fibroblastos/metabolismo , Substâncias de Crescimento/farmacologia , Humanos , Hibridização In Situ , Ceratose/genética , Ceratose/metabolismo , Metaloproteinase 10 da Matriz , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 3 da Matriz/genética , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/biossíntese , RNA Mensageiro/biossíntese , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Transcrição Gênica , Ativação Transcricional , Células Tumorais Cultivadas , Calinina
13.
J Biol Chem ; 276(13): 10134-44, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11121398

RESUMO

We have cloned a new human matrix metalloproteinase (MMP-28, epilysin) from human keratinocyte and testis cDNA libraries. Like most MMPs, epilysin contains a signal sequence, a prodomain with a PRCGVTD sequence, a zinc-binding catalytic domain with an HEIGHTLGLTH sequence, and a hemopexin-like domain. In addition, epilysin has a furin activation sequence (RRKKR) but has no transmembrane sequence. The exon-intron organization and splicing pattern of epilysin differ from that of other MMP genes. It has only 8 exons, and 5 exons are spliced at sites not used by other MMPs. Another novel feature of epilysin is that exon 4 is alternatively spliced to a transcript that does not encode the N-terminal half of the catalytic domain. Northern hybridization of tissue RNA indicated that epilysin is expressed at high levels in testis and at lower levels in lungs, heart, colon, intestine, and brain. RNase protection assay with various cell lines indicated that epilysin was selectively expressed in keratinocytes. Recombinant epilysin degraded casein in a zymography assay, and its proteolytic activity was inhibited by EDTA and by batimastat, a selective MMP inhibitor. Immunohistochemical staining showed expression of epilysin protein in the basal and suprabasal epidermis of intact skin. In injured skin, prominent staining for epilysin was seen in basal keratinocytes both at and some distance from the wound edge, a pattern that is quite distinct from that of other MMPs expressed during tissue repair. These findings suggest that this new MMP functions in several tissues both in tissue homeostasis and in repair.


Assuntos
Queratinócitos/metabolismo , Metaloproteinases da Matriz/biossíntese , Fenilalanina/análogos & derivados , Testículo/metabolismo , Adulto , Processamento Alternativo , Sequência de Aminoácidos , Animais , Baculoviridae/metabolismo , Sequência de Bases , Northern Blotting , Southern Blotting , Células CHO , Caseínas/metabolismo , Domínio Catalítico , Linhagem Celular , Clonagem Molecular , Cricetinae , DNA Complementar/metabolismo , Ácido Edético/metabolismo , Escherichia coli/metabolismo , Éxons , Biblioteca Gênica , Glutationa Transferase/metabolismo , Humanos , Imuno-Histoquímica , Íntrons , Masculino , Inibidores de Metaloproteinases de Matriz , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz Secretadas , Modelos Genéticos , Dados de Sequência Molecular , Fenilalanina/farmacologia , Filogenia , Inibidores de Proteases/farmacologia , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonucleases/metabolismo , Homologia de Sequência de Aminoácidos , Pele/metabolismo , Tiofenos/farmacologia , Distribuição Tecidual
16.
Protein Expr Purif ; 19(1): 66-73, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10833392

RESUMO

Membrane type 1 matrix metalloproteinase (MT1-MMP) is a membrane-bound proteinase and a cell-surface receptor and activator of gelatinase A in normal and neoplastic cells. We have expressed and purified a soluble deletion mutant of MT1-MMP lacking the transmembrane and cytoplasmic domains and an inactive mutant of the soluble MT1-MMP, where the active-site glutamic acid(240) was substituted by alanine (E240A). A baculovirus transfer vector coding for amino acids 21-539 of MT1-MMP (DeltaTM) and a similar vector coding for the mutation (E240ADeltaTM) were constructed for expression in insect cells. Both DeltaTM and E240ADeltaTM were secreted to the culture medium of infected High Five insect cells. They were then purified by cation-exchange followed by gel-filtration chromatography. DeltaTM was able to cleave denatured type I collagen and fibronectin and activate MMP-2/gelatinase-A, while E240ADeltaTM had only low proteolytic activity against denatured collagen I. The current expression and purification protocol should prove useful for the production of large amounts of enzymatically active soluble MT1-MMP.


Assuntos
Metaloendopeptidases/isolamento & purificação , Substituição de Aminoácidos , Animais , Baculoviridae/genética , Linhagem Celular , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Fibronectinas/química , Gelatina/química , Vetores Genéticos , Metaloproteinase 2 da Matriz/química , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/química , Metaloendopeptidases/genética , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Análise de Sequência de Proteína , Deleção de Sequência , Spodoptera/citologia
17.
J Biol Chem ; 275(20): 15006-13, 2000 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-10748199

RESUMO

Membrane-type-1 matrix metalloproteinase (MT1-MMP) has transmembrane and cytoplasmic domains, which target it to invasive fronts. We analyzed the role of the cytoplasmic tail by expressing wild type MT1-MMP and three mutants with progressively truncated C termini in human Bowes melanoma cells. We examined gelatinase A activation and the localization and processing of recombinant proteins in stable cell clones using gelatin zymography, immunoblotting, and immunofluorescence. Cell invasion was analyzed in vitro by Matrigel invasion assays. Gelatinase A was activated in all cell clones. However, the localization of MT1-MMP to the leading edge of migrating cells and cell invasion through Matrigel were strongly enhanced only in cells expressing either wild type or truncated MT1-MMP lacking 6 C-terminal amino acid residues (Delta577). Truncations of 10 or 16 amino acid residues in the cytoplasmic domain (Delta567 and Delta573, respectively) disturbed MT1-MMP localization. The expression of wild type and Delta577 MT1-MMPs induced also their cleavage to 43-kDa cell surface forms and the release of soluble, approximately 20-kDa N-terminal fragments containing the catalytic center. A synthetic MMP inhibitor but not a gelatinase inhibitor prevented the processing, suggesting that autocatalytic cleavage occurs. Purified soluble MT1-MMP was also autoproteolytically processed to 43- and 20-kDa forms in vitro. Our results indicate that the cytoplasmic domain has an important role in cell invasion by controlling both the targeting and degradation/turnover of MT1-MMP.


Assuntos
Metaloendopeptidases/química , Metaloendopeptidases/metabolismo , Clonagem Molecular , Colágeno , Citoplasma/enzimologia , Combinação de Medicamentos , Ativação Enzimática , Humanos , Laminina , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz Associadas à Membrana , Melanoma , Metaloendopeptidases/genética , Invasividade Neoplásica , Inibidores de Proteases/farmacologia , Proteoglicanas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Transfecção , Células Tumorais Cultivadas
18.
Gene ; 242(1-2): 75-86, 2000 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-10721699

RESUMO

Membrane type-1 matrix metalloproteinase (MT1-MMP) degrades extracellular matrix components directly and indirectly by activation of other matrix metalloproteinases (MMPs). In the present study, we have isolated and characterized the human MT1-MMP gene and its promoter. The gene consists of 10 exons and nine introns spanning more than 10 kilobases (kb). The locations of two exon-intron splicing sites are distinct from the preserved positions among other known MMP genes. Primer extension and RNAse and S1 nuclease protection analyses indicated that there are four major and several minor transcription start sites. The 5'-flanking sequence of the gene contains putative regulatory elements, including one Sp-1 site and four CCAAT-boxes, whereas there is no TATA-box. The Sp-1 binding site was functional, as shown by gel shift and supershift analyses. Transfection studies with promoter constructs containing 0.1 to 7.2 kb of 5'-flanking sequence coupled to a luciferase reporter gene indicated that the promoter contains additional positive and negative regulatory sequences. Deletion of the Sp-1 binding site by site-directed mutagenesis reduced luciferase activity by about 90%, demonstrating the crucial role of this element in maintaining MT1-MMP transcription. Our findings indicate that the human MT1-MMP promoter has distinctive structural and functional features compared with other MMP genes, which may lead to a unique expression pattern and regulation during physiological and pathological processes.


Assuntos
Metaloendopeptidases/genética , Regiões Promotoras Genéticas/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular , DNA/química , DNA/genética , DNA/metabolismo , Éxons , Regulação da Expressão Gênica/efeitos dos fármacos , Genes/genética , Humanos , Íntrons , Luciferases/genética , Luciferases/metabolismo , Metaloproteinases da Matriz Associadas à Membrana , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Fator de Transcrição Sp1/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica , Células Tumorais Cultivadas
19.
APMIS ; 108(3): 161-72, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10752684

RESUMO

Interplay between laminin-5 (Ln-5) and its integrin (Int) receptors alpha2beta1, alpha3beta1 and alpha6beta4 has been implicated in the progression and invasion of carcinomas. In this study we found abundant immunoreactivity for chains of Ln-5 (alpha3-beta3-gamma2) and Ln-10 (alpha5-beta1-gamma1), as well as for type VII collagen, in basement membranes (BM) of colorectal adenomas. In carcinomas of all differentiation grades, Lns were seen in tumor BMs, whereas type VII collagen was almost absent. Ln-5 appeared to accumulate along the invading edges of carcinomas, while Ln-10 was mostly absent. Immunoreactivity for Ln al chain, a component of Lns-1 and -3, was not seen in adenomas or carcinomas. Immunoreactivity for alpha2, alpha6, beta1 and beta4 Ints was found in all tumors and that for alpha3 Int in all adenomas and most of the carcinomas, often in colocalization with Ln-5. Immunoblotting of carcinoma tissues showed that the gamma2 chain of Ln-5 was present as typical Mr 105000 and 155000 isoforms. Immunoprecipitation experiments showed production of Ln-5 by cultured colon carcinoma cells. In quantitative cell adhesion experiments, function-blocking MAbs to alpha3 and beta1 Int subunits, but not those to Int alpha2 or alpha6 subunits, significantly inhibited the adhesion of cells to Ln-5. Our results suggest that BM composition in colorectal adenomas reflects the properties of surface epithelial BM of colorectal mucosa. In invading carcinomas, trimeric Ln-5, produced by carcinoma cells, is a major BM component and the cells use the alpha3beta1 Int complex for adhesion to Ln-5.


Assuntos
Adenoma/metabolismo , Carcinoma/metabolismo , Moléculas de Adesão Celular/metabolismo , Neoplasias Colorretais/metabolismo , Integrinas/metabolismo , Adenoma/patologia , Membrana Basal/metabolismo , Carcinoma/patologia , Adesão Celular/fisiologia , Moléculas de Adesão Celular/biossíntese , Neoplasias Colorretais/patologia , Células HT29 , Humanos , Integrina alfa3beta1 , Ligantes , Células Tumorais Cultivadas , Calinina
20.
Histochem J ; 31(2): 109-16, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10416682

RESUMO

Recent BP230-knockout experiments with subsequent blistering and recently identified plectin/HD1 mutations in epidermolysis bullosa simplex patients suggest that defective expression of BP230 and plectin/HD1 may predispose to blister formation in human skin. We have studied the expression of the epithelial adhesion complex as well as the basement membrane and anchoring fibril antigens in uninvolved dermatitis herpetiformis skin to find out if alterations can be detected in these structures predisposing to the blister formation typical of the disease. Ten uninvolved dermatitis herpetiformis skin specimens, which all showed clear granular deposits of IgA under the basement membrane in direct immunofluorescence and five normal skin specimens, were studied by indirect immunofluorescence technique. Six uninvolved dermatitis herpetiformis skin specimens showed distinctly decreased immunoreaction for BP230 and four uninvolved dermatitis herpetiformis skin specimens showed distinctly decreased immunoreaction for plectin/HD1. All five skin controls showed strong immunoreactions for BP230 and plectin/HD1. Other hemidesmosomal proteins including BP180 and integrin alpha6beta4, as well as basement membrane proteins laminin-5, laminin-1, nidogen and type IV collagen, and the anchoring fibril protein type VII collagen showed a normal strong expression. Our results suggest that alterations in BP230 and plectin/HD1 may contribute or predispose to blister formation in dermatitis herpetiformis skin.


Assuntos
Proteínas de Transporte , Colágeno , Proteínas do Citoesqueleto , Dermatite Herpetiforme/metabolismo , Desmossomos/química , Proteínas do Tecido Nervoso , Colágenos não Fibrilares , Pele/química , Autoantígenos/análise , Membrana Basal/química , Dermatite Herpetiforme/patologia , Derme/química , Desmossomos/ultraestrutura , Distonina , Endotélio Vascular/química , Técnica Direta de Fluorescência para Anticorpo , Humanos , Imunoglobulina A/análise , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/análise , Microscopia Eletrônica , Plectina , Pele/patologia , Pele/ultraestrutura , Colágeno Tipo XVII
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