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1.
Br J Dermatol ; 184(6): 1094-1105, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33289075

RESUMO

BACKGROUND: Drug survival rates reflect efficacy and safety and may be influenced by the availability of alternative treatment options. Little is known about time-dependent drug survival in psoriasis and the effect of increasing numbers of biologic treatment options. OBJECTIVES: To determine whether drug survival is influenced by the availability of treatment options and by factors such as gender, psoriatic arthritis or previous biologic treatment. METHODS: This observational, retrospective, multicentre cohort study analysed data from patients registered in the Austrian Psoriasis Registry (PsoRA) who were treated with biologics between 1 January 2015 and 30 November 2019. RESULTS: A total of 1572 patients who received 1848 treatment cycles were included in this analysis. The highest long-term Psoriasis Area and Severity Index improvement was observed after treatment with ixekizumab, followed by ustekinumab and secukinumab, adalimumab and etanercept. Overall, ustekinumab surpassed all other biologics in drug survival up to 48 months. However, when adjusted for biologic naïvety, its superiority vanished and drug survival rates were similar for ixekizumab (91·6%), secukinumab (90·2%) and ustekinumab (92·8%), all of them superior to adalimumab (76·5%) and etanercept (71·9%) at 12 months and beyond. Besides biologic non-naïvety (2·10, P < 0·001), the introduction of a new drug such as secukinumab or ixekizumab (relative hazard ratio 1·6, P = 0·001) and female gender (1·50, P = 0·019) increased the risk of treatment discontinuation overall, whereas psoriatic arthritis did not (1·12, P = 0·21). CONCLUSIONS: The time-dependent availability of drugs should be considered when analysing and comparing drug survival. Previous biologic exposure significantly influences drug survival. Women are more likely to stop treatment.


Assuntos
Produtos Biológicos , Psoríase , Adalimumab , Áustria , Estudos de Coortes , Etanercepte , Feminino , Humanos , Psoríase/tratamento farmacológico , Sistema de Registros , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Ustekinumab
2.
Br J Dermatol ; 176(6): 1475-1485, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28118487

RESUMO

BACKGROUND: (ECT) is an effective local treatment for cutaneous metastasis. Treatment involves the administration of chemotherapeutic drugs followed by delivery of electrical pulses to the tumour. OBJECTIVES: To investigate the effectiveness of ECT in cutaneous metastases of melanoma and to identify factors that affect (beneficially or adversely) the outcome. METHODS: Thirteen cancer centres in the International Network for Sharing Practices on Electrochemotherapy consecutively and prospectively uploaded data to a common database. ECT consisted of intratumoral or intravenous injection of bleomycin, followed by application of electric pulses under local or general anaesthesia. RESULTS: In total, 151 patients with metastatic melanoma were identified from the database, 114 of whom had follow-up data of 60 days or more. Eighty-four of these patients (74%) experienced an overall response (OR = complete response + partial response). Overall, 394 lesions were treated, of which 306 (78%) showed OR, with 229 showing complete response (58%). In multivariate analysis, factors positively associated with overall response were coverage of deep margins, absence of visceral metastases, presence of lymphoedema and treatment of nonirradiated areas. Factors significantly associated with complete response to ECT treatment were coverage of deep margins, previous irradiation of the treated area and tumour size (< 3 cm). One-year overall survival in this cohort of patients was 67% (95% confidence interval 57-77%), while melanoma-specific survival was 74% (95% confidence interval 64-84%). No serious adverse events were reported, and the treatment was in general very well tolerated. CONCLUSIONS: ECT is a highly effective local treatment for melanoma metastases in the skin, with no severe adverse effects noted in this study. In the presence of certain clinical factors, ECT may be considered for local tumour control as an alternative to established local treatments, or as an adjunct to systemic treatments.


Assuntos
Eletroquimioterapia/métodos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anestesia/métodos , Progressão da Doença , Eletroquimioterapia/efeitos adversos , Eletroquimioterapia/instrumentação , Eletrodos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Melanoma/patologia , Metástase Neoplásica , Dor/etiologia , Medição da Dor , Estudos Prospectivos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Carga Tumoral
3.
J Eur Acad Dermatol Venereol ; 29(9): 1742-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25665143

RESUMO

BACKGROUND: Ample evidence shows that switching from one biological agent to another may prove effective when response to the first one is inadequate. Nevertheless, there are little data so far showing the efficacy and safety of adalimumab in patients with plaque psoriasis who previously received another biologic agent. OBJECTIVE: We evaluated the 1-year effectiveness, safety and quality-of-life outcomes patients with psoriasis who had switched to adalimumab from other biologic therapies. METHODS: Forty-two patients who participated in this Austrian multicenter study were treated with adalimumab over a 1-year period, after switching from efalizumab, infliximab or etanercept. Effectiveness was assessed using standardized tools for measurement of disease severity [Psoriasis Area and Severity Index (PASI) and Nail Psoriasis Severity Index (NAPSI)] and quality of life [Dermatology Life Quality Index (DLQI)]. The study endpoints were evaluated using the all-treated population. RESULTS: The mean percentage of improvement at the end of the study was 74.3% for PASI, 81.6% for DLQI and 83.6% for NAPSI, demonstrating a considerable benefit of treatment with adalimumab. The safety profile observed was consistent with previous clinical trials for adalimumab, and no new safety signals were observed. CONCLUSION: Adalimumab therapy in patients with plaque psoriasis previously treated with other biologic agents demonstrates effectiveness, safety and improvement in quality of life.


Assuntos
Adalimumab/uso terapêutico , Produtos Biológicos/uso terapêutico , Psoríase/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Inibição de Migração Celular , Fármacos Dermatológicos/uso terapêutico , Etanercepte/uso terapêutico , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Infliximab/uso terapêutico , Estudos Prospectivos , Psoríase/diagnóstico , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento
4.
Sci Rep ; 12(1): 15078, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064563

RESUMO

With the introduction of the latest class of biologic drugs targeting interleukin (IL)-23p19, three new, highly effective drugs can be used for the treatment of chronic plaque psoriasis. However, poorer skin improvement as well as higher rates of serious adverse events have been reported for patients under real-world conditions (outside clinical trials). This accounts especially for patients who have already been treated with biologic drugs. We therefore aimed to determine effectiveness and safety of IL-23p19 inhibitors in real-world patients by analysing data from the Psoriasis Registry Austria (PsoRA) in this observational, retrospective, multicentre cohort study. Data for 197 patients (52.3% biologic-non-naïve), who were treated with anti-IL-23p19 antibodies (127 guselkumab, 55 risankizumab and 15 tildrakizumab) for at least 3 months, were eligible for analysis. In general, biologic-non-naïve patients displayed a less favourable response to anti-IL-23 treatment as compared to biologic-naïve patients. However, after correction for previous biologic exposure, few differences in PASI improvement were detected among biologic-naïve and -non-naïve patients treated with different IL-23p19 inhibitors. This indicates that treatment effectiveness is not related to the class of the previously administered therapy in biologic-non-naïve patients. Therefore, IL-23p19 inhibitors represent a promising treatment alternative for patients who have not responded to previous biologics. However, as with other biologic agents (including IL-17 inhibitors), we did not observe an entirely satisfactory treatment response (i.e. PASI < 3 and/or PASI 75) to anti-IL-23 treatment in one out of four to five patients. Adverse events (mainly non-severe infections) were observed in 23 (11.7%) patients with no major differences regarding the administered IL-23 inhibitor or previous biologic exposure.


Assuntos
Produtos Biológicos , Doença Enxerto-Hospedeiro , Psoríase , Áustria/epidemiologia , Produtos Biológicos/uso terapêutico , Estudos de Coortes , Doença Enxerto-Hospedeiro/tratamento farmacológico , Humanos , Interleucina-23 , Psoríase/tratamento farmacológico , Sistema de Registros , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
5.
Science ; 226(4674): 549-52, 1984 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-6093251

RESUMO

Two of three chimpanzees given plasma from patients with acquired immune deficiency syndrome (AIDS) or pre-AIDS showed serum antibodies to type III human T-cell leukemia virus (HTLV-III) 10 to 12 weeks after transfusion. One animal also developed lymphadenopathy, transient depression of the ratio of T4 to T8 lymphocytes, and impaired blastogenic responses. No opportunistic infections occurred. Adenopathy persisted for 32 weeks, and antibody to HTLV-III persisted for at least 48 weeks. This transmission of HTLV-III by lymphocyte-poor plasma confirms the potential risk of such plasma or plasma derivatives to recipients. The susceptibility of the chimpanzee to HTLV-III infection and the ability to simulate the human lymphadenopathy syndrome in this animal makes it a valuable model for further study of AIDS.


Assuntos
Síndrome da Imunodeficiência Adquirida/transmissão , Deltaretrovirus , Modelos Animais de Doenças , Pan troglodytes , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/patologia , Animais , Anticorpos Antivirais/imunologia , Deltaretrovirus/imunologia , Humanos , Contagem de Leucócitos , Linfonodos/patologia , Pan troglodytes/microbiologia , Linfócitos T
6.
Science ; 225(4669): 1473-6, 1984 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-6089348

RESUMO

Antibodies specific for human T-cell leukemia-lymphoma virus type I (HTLV-I) were demonstrated in serum samples from various groups of people in South Africa, Uganda, Ghana, Nigeria, Tunisia, and Egypt. The samples had been collected for other purposes and were presumably selected without bias toward clinical conditions associated with HTLV infections. Regional differences in antibody positivity were observed, indicating widely distributed loci of occurrence of HTLV on the African continent in people of both black and white ancestry. Two patients with high titers of antibody to HTLV-I had some signs of adult T-cell leukemia-lymphoma. In several groups a high frequency of false positive serum reactions was indicated when specific confirmation steps were included in the assay. Further characterization of these sera revealed highly elevated immunoglobulin levels, possibly due to polyclonal activation of immunoglobulin synthesis in these subjects. The possibility that related cross-reactive human retroviruses coexist in the same groups was not eliminated.


Assuntos
Anticorpos Antivirais/análise , Deltaretrovirus/imunologia , Adulto , África , População Negra , Linfoma de Burkitt/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Feminino , Humanos , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Retroviridae/imunologia , Linfócitos T , População Branca
7.
Science ; 227(4690): 1036-8, 1985 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2983417

RESUMO

Fifty of 75 serum samples collected in the West Nile district of Uganda between August 1972 and July 1973 contained antibodies reactive with human T-cell leukemia (lymphotropic) virus type 3 (HTLV-III; mean titer, 601), while 12 of 75 samples were positive in a similar test for HTLV type 1 (HTLV-1) antibodies (mean titer, 236). The samples were screened by enzyme-linked immunosorbent assay and positive results were confirmed by a newly developed unlabeled antibody-peroxidase procedure with enhanced sensitivity for detection of antibody binding to immunoblots of HTLV-III antigen, demonstrating antibodies to proteins with molecular weights of 24,000, 41,000, and 76,000 in nearly all positive samples. Analysis of titration data indicated enhanced titers of antibody against HTLV-III and HTLV-I when coinfection occurred. The high prevalence and relatively low titers [compared to serum from patients with acquired immune deficiency syndrome (AIDS)] of antibodies recognizing HTLV-III proteins in sera from this population at a time that may predate or coincide with the appearance or spread of the AIDS agent (HTLV-III) suggest that the virus detected may have been a predecessor of HTLV-III or is HTLV-III itself but existing in a population acclimated to its presence. It further suggests an African origin of HTLV-III.


Assuntos
Infecções por Retroviridae/epidemiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/microbiologia , Criança , Deltaretrovirus/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/microbiologia , Uganda
8.
Methods Mol Biol ; 527: 257-67, x, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19241019

RESUMO

In view of the importance of information transfer mediated throughout the cell by recognition, phosphorylation or dephosphorylation of kinases, their adapters, or substrates, this method was developed. The method provides a potent research tool for rapidly generating and testing these substrates as modeled by synthetic peptide arrays. The peptides or phosphorylated peptides are automatically generated on the inner surfaces of microplate wells, covalently linked to a polylysine polymer so that they are in a sterically favorable conformation, immediately available for in situ testing. Products up to 18 amino acids long have shown excellent mass spectral homogeneity. Thus, determinate peptide libraries can be ready for testing in as little as 2 days after the conception of an experiment. The process can be easily automated using robotic liquid handlers and is extremely rapid, sensitive, and economical. Optionally, the method can be upgraded to a higher throughput level using more powerful workstations with greater capacity, such as the Biomek FX, or any similar robotics capable of transfer-from-file logic to guide synthesis cycles.


Assuntos
Fosfopeptídeos/biossíntese , Análise Serial de Proteínas/instrumentação , Análise Serial de Proteínas/métodos , Proteínas Tirosina Quinases/análise , Proteínas Tirosina Quinases/metabolismo , Animais , Anticorpos Imobilizados/metabolismo , Anticorpos Imobilizados/farmacologia , Anticorpos Fosfo-Específicos/metabolismo , Anticorpos Fosfo-Específicos/farmacologia , Automação/instrumentação , Automação/métodos , Humanos , Microquímica/instrumentação , Microquímica/métodos , Fosfopeptídeos/análise
10.
Cancer Res ; 37(10): 3585-9, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-71196

RESUMO

Syrian hamster embryo fibroblasts transformed in vitro with benzo(a)pyrene were analyzed for the presence of type C viral components, including extra- and intracellular reverse transcriptase activity, intracellular type C hamster virus-related RNA, and cellular hamster virus group-specific antigen. No evidence could be obtained for the presence of any of these components, although they were easily detectable in hamster fibroblasts producing either B-34 virus (a hamster virus pseudotype of Harvey murine sarcoma virus which contains an excess of helper type C hamster virus) or Harvey virus itself. In addition, intracellular viral RNA could not be detected in normal hamster embryo fibroblasts, in hamster fibroblasts transformed with simian virus 40, or in newborn hamster kidney and liver. Thus the detectable expression of the indigenous hamster type C virus is not required to maintain the transformed phenotype of these cells.


Assuntos
Benzopirenos , Transformação Celular Neoplásica , Retroviridae/isolamento & purificação , Antígenos Virais , Células Cultivadas , Hibridização de Ácido Nucleico , RNA Viral/análise , DNA Polimerase Dirigida por RNA/análise , Retroviridae/imunologia , Retroviridae/metabolismo
11.
Leukemia ; 6(11): 1229-31, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1331626

RESUMO

Human herpesvirus-6 (HHV-6), a ubiquitous virus that causes exanthem subitum and occasional cases of infectious mononucleosis, hepatitis and other viral syndromes, has also been associated with acute lymphocytic leukemia (ALL) in children. To further investigate this association, we obtained sera from 50 patients with ALL and 50 age-sex matched controls. Antibodies to HHV-6 were determined using ELISA and indirect immunofluorescent antibody (IFA) tests. No significant difference between antibody titers in the cases and controls was observed. Since seroepidemiologic studies have demonstrated higher HHV-6 antibody titers in young children than in adults, this serologic study suggests that the previous association reported for HHV-6 and ALL was a result of the age of the population rather than a relationship between the virus and the disease.


Assuntos
Anticorpos Antivirais/análise , Infecções por Herpesviridae/complicações , Herpesvirus Humano 6/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
12.
AIDS ; 3(4): 235-7, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2500957

RESUMO

One hundred and ninety-nine patients with a history of intravenous drug abuse, and enrolled on the St Luke's-Roosevelt Hospital Center Methadone Program, had baseline evaluations performed from September 1984 to April 1987. The study was designed to examine immunologic parameters associated with HIV seropositivity and those predictive of progression to AIDS-related complex (ARC) and AIDS. Sixty-four patients (32%) had antibodies to HIV by enzyme-linked immunosorbent assay (ELISA), with confirmation by Western blot and none of these patients had ARC or AIDS at the time of initial evaluation. The mean values for white blood-cell count, absolute lymphocyte count, proportion and absolute CD4, and CD4/CD8 ratio were decreased significantly in the HIV-seropositive group compared with the HIV-seronegative group. On the other hand, levels of circulating beta 2-microglobulin, SCD8, SIL-2R, and HIV p24 antigen were significantly elevated in the HIV-seropositive group compared with the HIV-seronegative group.


Assuntos
Complexo Relacionado com a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Anticorpos Anti-HIV/análise , Metadona/uso terapêutico , Transtornos Relacionados ao Uso de Substâncias/imunologia , Complexo Relacionado com a AIDS/complicações , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Antígenos de Diferenciação de Linfócitos T/análise , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Antígenos HIV/análise , Proteína do Núcleo p24 do HIV , Humanos , Contagem de Leucócitos , Masculino , Cidade de Nova Iorque , Receptores de Interleucina-2/análise , Proteínas dos Retroviridae/análise , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Microglobulina beta-2/análise
13.
J Immunol Methods ; 91(2): 181-6, 1986 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-3016097

RESUMO

We examined the usefulness of a counterimmunoelectrophoresis (CIE) technique for detecting antibodies to HTLV-III using sera that previously had been assessed for antibodies to HTLV-III by the standard enzyme-linked immunosorbent assay (ELISA). We selected a subset of 53 sera from patients with the acquired immune deficiency syndrome (AIDS) or the generalized lymphadenopathy syndrome (GLS) in which 81.1% were initially ELISA-positive, and 96.2% were positive by Western blot technique. In our standard HTLV-III CIE technique, 58.5% were positive and repeat testing increased the yield to 67.9%. Varying several parameters of the standard CIE assay did not improve sensitivity. We also studied 20 ELISA-negative and 10 ELISA-borderline sera from normal controls; all were negative by CIE. These results indicate that CIE may be used for detection of human serum antibodies to HTLV-III, but that the present assay was less sensitive than the HTLV-III ELISA.


Assuntos
Anticorpos Antivirais/análise , Deltaretrovirus/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Animais , Contraimunoeletroforese/métodos , Cães , Ensaio de Imunoadsorção Enzimática , Humanos
14.
AIDS Res Hum Retroviruses ; 10(11): 1581-3, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7888214

RESUMO

PIP: Nucleotide sequences were obtained for portions of the envelope and gag genes of 4 HIV-1 isolates from Nigeria. The gag gene sequences clustered with previously described gag sequences from Gabon, Zaire, and Taiwan, which form the G clade of HIV-1. This documented for the first time the presence of subgroup G viruses in Nigeria. The env gene sequences were most closely related to env sequences reported from 2 isolates previously classified as gag subgroup G and, with those 2 env sequences, defined the subgroup G env genotype. Virus isolates were obtained by cocultivation of peripheral blood mononuclear cells (PBMCs) from Nigerian AIDS patients (isolates JV1018 and JP88) or healthy prostitutes (G3 and G9) with normal uninfected PBMCs (JV1083, JP88, and G3) or GEM-SS, a T cell line (G9). Clones containing env and gag gene sequences were obtained by polymerase chain reaction amplification, using DNA from these cultures. The region of gag amplified by primers SK37 and SK39 containing BamHI and KpnI sites, respectively, in 5' tails, was cloned into the KpnI-BamHI site of pKSBluescript and sequenced. When the gag sequences from 2 of the Nigerian viruses were subtyped by weighted parsimony, both viruses grouped with others of the gag G subgroup. A similar analysis of env sequences from all 4 Nigerian isolates showed that they were most closely related to 2 env sequences that had been assigned to env subgroup G. The Nigerian env sequences clustered more closely with each other than they did with the other 2 subgroup G viruses. Consensus of the inferred amino acid sequences of the 4 env genes showed that the V3 loop closely resembled the A to F consensus. 8 positions in the Nigerian consensus sequence appeared to be unique. However, whether these are signature residues for Nigerian subgroup G isolates or for subgroup G isolates will require the characterization of more isolates.^ieng


Assuntos
Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Sequência de Aminoácidos , Sequência de Bases , Sequência Consenso , Primers do DNA/genética , DNA Viral/genética , Feminino , Genes env , Genes gag , Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Humanos , Dados de Sequência Molecular , Nigéria/epidemiologia , Filogenia , Homologia de Sequência de Aminoácidos
15.
Am J Trop Med Hyg ; 42(4): 374-9, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1970459

RESUMO

The human T-lymphotropic virus (HTLV) and associated diseases, adult T cell leukemia and spastic paraparesis, appear to be endemic in southwestern Japan and the Caribbean. This cross-sectional population-based study was conducted to describe the seroepidemiology of HTLV in the Republic of Panama. HTLV antibody was measured by first generation and commercial ELISA tests and confirmed by competitive binding ELISA, a radioimmunoassay for anti-p 24, and Western blot. Of 3,231 subjects greater than or equal to 15 years of age, 135 (4.2%) had antibody detected in ELISA screening tests, but because only 20% were confirmed positive, HTLV seroprevalence varied from 0.2-2% throughout the Republic. Infection with HTLV clustered in Guaymi Indians living in Bocas del Toro province (9.9% prevalence rate). With the exception of Guaymi Indians, no major geographic, urban/rural, male/female or racial differences in antibody prevalence were observed; specifically, HTLV infection rates were not elevated in black Panamanians. Clustering of infection in an isolated Amerind population must be further investigated. The small proportion of screen-positive sera which confirmed positive illustrates the importance of strict uniform criteria for seropositivity.


Assuntos
Anticorpos Antideltaretrovirus/análise , Infecções por Deltaretrovirus/epidemiologia , Deltaretrovirus/imunologia , Ligação Competitiva , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Panamá/epidemiologia , Radioimunoensaio
17.
Peptides ; 32(9): 1840-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21871510

RESUMO

Tissue inhibitor of metalloproteinases-2 (TIMP-2) inhibits angiogenesis by several mechanisms involving either MMP inhibition or direct endothelial cell binding. The primary aim of this study was to identify the TIMP-2 region involved in binding to the previously identified receptor integrin α3ß1, and to determine whether synthetic peptides derived from this region retained angio-inhibitory and tumor suppressor activity. We demonstrated that the N-terminal domain of TIMP-2 (N-TIMP-2) binds to α3ß1 and inhibits vascular endothelial growth factor-stimulated endothelial cell growth in vitro, suggesting that both the α3ß1-binding domain and the growth suppressor activity of TIMP-2 localize to the N-terminal domain. Using a peptide array approach we identify a 24 amino acid region of TIMP-2 primary sequence, consisting of residues Ile43-Ala66, which shows α3ß1-binding activity. Subsequently we demonstrate that synthetic peptides from this region compete for TIMP-2 binding to α3ß1 and suppress endothelial growth in vitro. We define a minimal peptide sequence (peptide 8-9) that possesses both angio-inhibitory and, using a murine xenograft model of Kaposi's sarcoma, anti-tumorigenic activity in vivo. Thus, both the α3ß1-binding and the angio-inhibitory activities co-localize to a solvent exposed, flexible region in the TIMP-2 primary sequence that is unique in amino acid sequence compared with other members of the TIMP family. Furthermore, comparison of the TIMP-2 and TIMP-1 protein 3-D structures in this region also identified unique structural differences. Our findings demonstrate that the integrin binding, tumor growth suppressor and in vivo angio-inhibitory activities of TIMP-2 are intimately associated within a unique sequence/structural loop (B-C loop).


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Integrina alfa3beta1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Sequência de Aminoácidos , Animais , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Camundongos , Camundongos Nus , Análise em Microsséries , Dados de Sequência Molecular , Neovascularização Patológica/metabolismo , Peptídeos/administração & dosagem , Peptídeos/síntese química , Peptídeos/farmacologia , Ligação Proteica , Sarcoma de Kaposi/patologia , Inibidor Tecidual de Metaloproteinase-1/química , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/química , Fator A de Crescimento do Endotélio Vascular/farmacologia
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