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1.
J Exp Med ; 163(6): 1529-38, 1986 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-3011949

RESUMO

It has generally been assumed that most if not all CTL specific for vesicular stomatitis virus (VSV)-infected cells recognize the viral glycoprotein (G), an integral membrane protein abundantly expressed on infected cell surfaces. Using recombinant vaccinia viruses containing copies of cloned VSV genes to examine CTL recognition of VSV, we have confirmed that G is recognized by VSV-specific CTL. More interestingly, however, we have also found that nucleocapsid protein (N), an internal virion protein, can be detected on infected cell surfaces using mAb, and serves as a major target antigen for VSV-specific CTL. In contrast to the highly serotype-specific recognition of G, N is recognized by a major population of CTL able to lyse cells infected with either the Indiana or New Jersey VSV serotypes. Using target cells expressing a cloned MHC class I gene, we could directly show that CTL recognition of N occurs in the context of the MHC Ld molecule.


Assuntos
Capsídeo/imunologia , Vírus da Influenza A/imunologia , Glicoproteínas de Membrana , Linfócitos T Citotóxicos/imunologia , Vírus da Estomatite Vesicular Indiana/imunologia , Vesiculovirus , Proteínas do Core Viral/imunologia , Proteínas do Envelope Viral , Proteínas Virais/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Capsídeo/genética , Linhagem Celular , Sarcoma de Mastócitos , Camundongos , Camundongos Endogâmicos DBA , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vaccinia virus/genética , Vírus da Estomatite Vesicular Indiana/genética , Proteínas do Core Viral/genética , Proteínas Virais/genética
2.
Science ; 227(4685): 433-5, 1985 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-2981435

RESUMO

Vesicular stomatitis virus (VSV) causes a contagious disease of horses, cattle, and pigs. When DNA copies of messenger RNA's for the G or N proteins of VSV were linked to a vaccinia virus promoter and inserted into the vaccinia genome, the recombinants retained infectivity and synthesized VSV polypeptides. After intradermal vaccination with live recombinant virus expressing the G protein, mice produced VSV-neutralizing antibodies and were protected against lethal encephalitis upon intravenous challenge with VSV. In cattle, the degree of protection against intradermalingually injected VSV was correlated with the level of neutralizing antibody produced following vaccination.


Assuntos
Clonagem Molecular , Glicoproteínas de Membrana , Vaccinia virus/genética , Vírus da Estomatite Vesicular Indiana/imunologia , Proteínas do Envelope Viral , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Viroses/veterinária , Animais , Anticorpos Antivirais/análise , Bovinos , Doenças dos Bovinos/prevenção & controle , DNA Recombinante , Genes Virais , Camundongos , Óperon , Estomatite/prevenção & controle , Estomatite/veterinária , Vacinação/veterinária , Vírus da Estomatite Vesicular Indiana/genética , Proteínas Virais/biossíntese , Viroses/prevenção & controle
3.
Science ; 228(4700): 737-40, 1985 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-2986288

RESUMO

In humans, herpes simplex virus causes a primary infection and then often a latent ganglionic infection that persists for life. Because these latent infections can recur periodically, vaccines are needed that can protect against both primary and latent herpes simplex infections. Infectious vaccinia virus recombinants that contain the herpes simplex virus type 1 (HSV-1) glycoprotein D gene under control of defined early or late vaccinia virus promoters were constructed. Tissue culture cells infected with these recombinant viruses synthesized a glycosylated protein that had the same mass (60,000 daltons) as the glycoprotein D produced by HSV-1. Immunization of mice with one of these recombinant viruses by intradermal, subcutaneous, or intraperitoneal routes resulted in the production of antibodies that neutralized HSV-1 and protected the mice against subsequent lethal challenge with HSV-1 or HSV-2. Immunization with the recombinant virus also protected the majority of the mice against the development of a latent HSV-1 infection of the trigeminal ganglia. This is the first demonstration that a genetically engineered vaccine can prevent the development of latency.


Assuntos
Engenharia Genética , Herpes Simples/prevenção & controle , Vaccinia virus/genética , Proteínas do Envelope Viral , Proteínas Virais/genética , Animais , Anticorpos Antivirais/imunologia , Herpes Simples/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Simplexvirus/genética , Simplexvirus/imunologia , Vacinas , Proteínas Virais/imunologia
4.
Oncogene ; 11(9): 1711-9, 1995 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-7478598

RESUMO

In vitro infection of human B lymphocytes with Epstein-Barr virus (EBV) results in their growth transformation and establishment of immortalised lymphoblastoid cell lines. The virus was recently found to encode a homologue of the pleitropic cytokine interleukin-10 (IL-10), which has wide ranging effects on the immune system. We have investigated the effect of this virally encoded growth factor on the ability of EBV to immortalize B lymphocytes from tonsils and from adult and neonatal blood. Recombinant viral interleukin-10 (vIL-10) was found to increase dramatically the growth transformation of B cells from all three populations infected with either the highly transforming type 1 strain B95-8 or the less efficient type 2 strain BL16. This striking enhancement of transforming ability in the presence of viral IL-10 may be in part due to increased viability of the B cells during infection and decreased levels of interferon-gamma, a cytokine known to inhibit EBV transformation. Thus viral IL-10 influences a number of cell types of the immune system to allow the enhanced outgrowth of EBV transformed cells.


Assuntos
Linfócitos B/imunologia , Transformação Celular Viral , Herpesvirus Humano 4/imunologia , Interleucina-10/farmacologia , Ativação Linfocitária/fisiologia , Adulto , Linfócitos B/efeitos dos fármacos , Linfócitos B/virologia , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Sangue Fetal , Humanos , Recém-Nascido , Interleucina-10/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Fases de Leitura Aberta , Tonsila Palatina , Especificidade da Espécie
5.
Microbes Infect ; 2(14): 1677-85, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11137041

RESUMO

There is increasing evidence to implicate a role for CD8(+) T cells in protective immunity against tuberculosis. Recombinant vaccinia (rVV) expressing Mycobacterium tuberculosis (MTB) proteins can be used both as tools to dissect CD8(+) T-cell responses and, in attenuated form, as candidate vaccines capable of inducing a balanced CD4(+)/CD8(+) T-cell response. A panel of rVV was constructed to express four immunodominant secreted proteins of MTB: 85A, 85B and 85C and ESAT-6. A parallel group of rVV was constructed to include the heterologous eukaryotic tissue plasminogen activator (tPA) signal sequence to assess if this would enhance expression and immunogenicity. Clear expression was obtained for 85A, 85B and ESAT-6 and the addition of tPA resulted in N-glycosylation and a 4-10-fold increase in expression. Female C57BL/6 mice were immunised using the rVV-Ag85 constructs, and interleukin-2 and gamma-interferon were assayed using a co-culture of immune splenocytes and recall antigen. There was a marked increase in cytokine production in mice immunised with the tPA-containing constructs. We report the first data demonstrating enhanced immunogenicity of rVV using a tPA signal sequence, which has significant implications for future vaccine design.


Assuntos
Aciltransferases , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/biossíntese , Vacinas Bacterianas/imunologia , Mycobacterium tuberculosis/imunologia , Partícula de Reconhecimento de Sinal , Ativador de Plasminogênio Tecidual/química , Vaccinia virus/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Clonagem Molecular , Técnicas de Cocultura , Feminino , Vetores Genéticos , Glicosilação , Interferon gama/análise , Interleucina-2/análise , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Dobramento de Proteína
6.
Transplantation ; 71(4): 552-60, 2001 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-11258435

RESUMO

BACKGROUND: The application of gene therapy to prevent allograft rejection requires the development of noninflammatory vectors. We have therefore investigated the use of a nonviral system, transferrin-mediated lipofection, to transfer genes into the cornea with the aim of preventing corneal graft rejection. METHODS: Rabbit and human corneas were cultured ex vivo and transfected with either lipofection alone or in conjunction with transferrin. The efficiency of transfection, localization, and kinetics of marker gene expression were determined. Strategies to increase gene expression, using chloroquine and EDTA, were investigated. In addition to a marker gene, a gene construct encoding viral interleukin 10 (vIL-10) was transfected and its functional effects were examined in vitro. RESULTS: Transferrin, liposome, and DNA were demonstrated to interact with each other, forming a complex. This complex was found to deliver genes selectively to the endothelium of corneas resulting in gene expression. Treatment of corneas with chloroquine and EDTA increased the transfection efficiency eight-fold and threefold, respectively. We also demonstrated that constructs encoding vIL-10 could be delivered to the endothelium. Secreted vIL-10 was shown to be functionally active by inhibition of a mixed lymphocyte reaction. CONCLUSIONS: Our data indicate that transferrin-mediated lipofection is a comparatively efficient nonviral method for delivering genes to the corneal endothelium. Its potential for use in preventing graft rejection is shown by the ability of this system to induce vIL-10 expression at secreted levels high enough to be functional.


Assuntos
Endotélio Corneano/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos/administração & dosagem , Receptores da Transferrina/genética , Animais , Cloroquina/farmacologia , Citomegalovirus/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-10/genética , Regiões Promotoras Genéticas , Coelhos , Fatores de Tempo , Transfecção , beta-Galactosidase/genética
7.
Immunol Lett ; 16(3-4): 243-8, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3327813

RESUMO

Many successful vaccines are based on live attenuated viruses. An attractive idea is to genetically engineer these live attenuated vaccines so that they express protective antigens from other pathogens. Vaccinia virus, the smallpox vaccine, can be considered as the prototype for this sort of approach. Over one hundred examples of vaccinia virus recombinants are recorded in the literature and many of these have been shown to protect animals against challenge with the appropriate pathogen. Several problems need to be overcome before these recombinants can be tested in humans; however, the potential advantages of this approach ensure vigorous study of these difficulties. Vaccinia virus recombinants can also be used to dissect the cell-mediated and humoral immune responses to pathogens, and have thus proved to be valuable laboratory tools. However, it remains to be seen if they will also be used in other than experimental situations.


Assuntos
Vaccinia virus/imunologia , Vacinas Virais/isolamento & purificação , Animais , DNA Recombinante , Vacinas Atenuadas/isolamento & purificação , Vacínia/imunologia , Vacínia/prevenção & controle , Vaccinia virus/genética
8.
Viral Immunol ; 12(2): 97-105, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10413356

RESUMO

Recombinant vaccinia viruses that expressed the nontoxic C-domain of Clostridium perfringens alpha-toxin were constructed. The J2R (thymidine kinase [TK] gene) and B13R (serpin 2 [SPI-2] gene) loci were used as insertion sites for the clostridial DNA, and expression of the foreign protein was measured in each case. A double recombinant that encoded the alpha-toxin truncate at the B13R locus and the protective antigen of Bacillus anthracis at the J2R locus was also constructed. Although differences in expression of the alpha-toxin C-domain were recorded, all of the vaccinia recombinants protected mice against a lethal challenge with alpha-toxin demonstrating that a recombinant vaccinia virus can be used to provide protection against a toxin challenge that is known to be solely antibody mediated.


Assuntos
Toxinas Bacterianas/imunologia , Proteínas de Ligação ao Cálcio , Clostridium perfringens/imunologia , Vetores Genéticos , Fosfolipases Tipo C/imunologia , Vaccinia virus , Animais , Toxinas Bacterianas/genética , Linhagem Celular , Chlorocebus aethiops , Clostridium perfringens/genética , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Recombinação Genética , Fosfolipases Tipo C/genética
9.
Arch Surg ; 117(5): 561-7, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7073475

RESUMO

We reviewed nine cases in which either limg-threatening or life-threatening complications developed due to streptococcal infection. Our findings indicate important changes in the pattern of this fulminating illness since its original description in 1924. A higher mortality reflects increased longevity with a greater frequency of impaired host resistance and degenerative diseases involving vital organs. Initial symptoms and signs often mimic acute thrombophlebitis, acute arthritis, deep soft-tissue trauma, or acute vascular occlusion. The emergence of multiple organ failure and serious coagulation disorders are a challenge to current therapy. A diagnostic algorithm was developed to aid in the early diagnosis and management of this life-threatening infection.


Assuntos
Gangrena/diagnóstico , Infecções Estreptocócicas/diagnóstico , Adulto , Idoso , Feminino , Gangrena/etiologia , Gangrena/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estreptocócicas/terapia
10.
Arch Surg ; 115(9): 1031-6, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7416949

RESUMO

Complications associated with jejunoileal bypass for morbid obesity are being recognized more frequently. A variety of mechanical obstructions in the defunctionalized small-bowel segment have recently been corrected in seven surgical patients. Volvulus of the defunctional limb was the most frequent cause of obstruction. Intussusception, bypass enteritis, fascial hernia, and adhesive bands were also causes of obstruction. Radiographic contrast studies were valuable in establishing the preoperative diagnosis. The altered small-intestinal anatomy predisposed these patients to a uniquely subtle and dangerous form of closed-loop obstruction. Prompt recognition was based on patient history and physical findings. Characteristic roentgenographic findings often confirmed the diagnosis. Clinical suspicision of these small-bowel obstructive syndromes may lead to early surgical treatment.


Assuntos
Íleo/cirurgia , Obstrução Intestinal/etiologia , Jejuno/cirurgia , Obesidade/terapia , Complicações Pós-Operatórias/etiologia , Adulto , Síndrome da Alça Aferente/etiologia , Feminino , Humanos , Obstrução Intestinal/diagnóstico por imagem , Intussuscepção/etiologia , Masculino , Radiografia
11.
Methods Mol Biol ; 7: 129-46, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-21416353

RESUMO

Vaccinia virus has been used to express many diverse genes, such as prokaryotic enzymes, eukaryotic growth factors, protozoan structural proteins, and >50 different virus gene products (for reviews, seerefs. 1-3). The widespread use of vaccinia virus as a vector owes much to the ease of generating recombinants, the authenticity of the foreign gene product, and the wide variety of uses to which they have been put. For example, HIV 1 (human immunodeficiency virus) envelope glycoprotein expressed by a vaccinia recombinant is biologically and antigenically indistinguishable from the authentic glycoprotein (4-bi7). Recombinants have been used to generate HIV-neutralizing antibody (4-6) to immunize animals and humans (8-10), and to analyze cytotoxic T-cell and antibody-dependent cellular cytotoxicity (11-13). Furthermore, the antigenicity of HIV enuhas been improved by site-directed mutagenesis of protease cleavage sites (14).

12.
Am J Surg ; 142(1): 89-95, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7020461

RESUMO

Tabulation of the diagnostic evaluation and operative treatment of 16 patients with aldosterone-producing adrenal adenomas is presented. The diagnosis of primary aldosteronism was confirmed in all patients by biochemical and radiologic studies. Selective venous sampling of adrenal vein aldosterone localized the adenoma in 14 patients and proved to be the single most helpful diagnostic procedure. Computed tomography was used recently to confirm the localization of these interesting lesions and may become the initial noninvasive diagnostic study. Confidence in the accuracy of preoperative localization has led to the choice of the posterior approach to the involved adrenal gland. Postoperative morbidity has been low regardless of the operative approach; however, subjective patient acceptance of posterior adrenalectomy suggests a more comfortable convalescence and a more rapid return to normal activity.


Assuntos
Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Hiperaldosteronismo/cirurgia , Adenoma/induzido quimicamente , Adenoma/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/induzido quimicamente , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Hiperfunção Adrenocortical/diagnóstico por imagem , Adulto , Idoso , Aldosterona/efeitos adversos , Feminino , Humanos , Hiperaldosteronismo/complicações , Hiperaldosteronismo/diagnóstico por imagem , Hiperplasia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia
13.
Am Surg ; 58(12): 766-71, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1456604

RESUMO

Laparoscopic cholecystectomy has achieved wide acceptance as the preferred treatment for symptomatic gallbladder disease. Yet there are alarming reports of iatrogenic bile duct injuries. To establish a comparison standard, the incidence of iatrogenic bile duct injury during conventional cholecystectomy has to be known. A single institutional retrospective review of 1,617 consecutive open cholecystectomies between 1980 and 1989 was performed. Eight patients (0.49%) sustained iatrogenic bile duct injury in this study. Inflammation, anatomic variation, or both were contributing factors in all injuries. Operative cholangiography identified the injury at the initial operation in three patients. Treatment consisted of either primary ductal repair, ductal repair over a stent, or ductal-enteric anastomosis. There were no late complications after surgery (follow-up 26 to 97 months; mean 50.9 months). The implications for laparoscopic cholecystectomy are apparent. Iatrogenic bile duct injuries are associated with acute inflammation and/or variant ductal anatomy; routine operative cholangiography assumes increased importance; and immediate repair of the injury minimizes long-term complications.


Assuntos
Ductos Biliares/lesões , Colecistectomia , Complicações Intraoperatórias/epidemiologia , Ferimentos e Lesões/epidemiologia , Doença Aguda , Anastomose Cirúrgica/normas , California/epidemiologia , Colangiografia , Colecistectomia/métodos , Colecistite/epidemiologia , Colecistite/patologia , Colecistite/cirurgia , Coledocostomia/normas , Doença Crônica , Seguimentos , Hospitais Universitários , Humanos , Incidência , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Stents/normas , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/cirurgia
16.
World J Microbiol Biotechnol ; 7(2): 137-49, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24424925

RESUMO

Recombinant DNA technology has made it possible to express foreign genes in viruses and bacteria. This has led to the idea of engineering live attenuated vaccines to express protective antigens from foreign pathogens. Vaccinia virus, the smallpox vaccine, has been used to ploneer this approach. Several hundred recombinants have been recorded in the literature and many of them have been shown to protect animals against challenge with the appropriate pathogen. Although mixed results have been obtained with experiments in humans and primates, and there is some concern over complications associated with vaccination, recent advances in our under-standing of the basic biology of vaccinia virus should allow these difficulties to be overcome. Whatever the final outcome of proposals to use vaccinia recombinants in humans, vaccinia has proved to be a valuable general purpose expression system and is particularly useful for studying cellular immunity. The success of field trials with a vaccinia recombinant expressing the rabies virus glycoprotein may lead to widespread use of vaccinia recombinants as animal vaccines. Therefore it seems likely that vaccinia recombinants will continue to play a useful part in the development of new vaccines for infectious disease.

17.
EMBO J ; 4(12): 3229-34, 1985 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3004944

RESUMO

The Epstein-Barr virus membrane antigen gene gp340 was isolated, inserted into several strains of vaccinia virus and expressed under the control of a vaccinia virus promoter. The EBV-derived protein which was produced by the recombinant vaccinia viruses was heavily glycosylated, readily labelled with threonine, could be detected at the surface of infected cells and had a mol. wt. of approximately 340 kd, all of which are properties of the authentic gp340. Polyclonal rabbit antisera against gp340 and an EBV-neutralising anti-gp340 monoclonal antibody both recognised cells infected with the recombinant vaccinia viruses. Moreover, rabbits vaccinated with one of the recombinants produced antibodies that recognised EBV-containing lymphoblastoid cells and neutralised EBV.


Assuntos
Anticorpos Antivirais/análise , Formação de Anticorpos , Genes Virais , Genes , Herpesvirus Humano 4/imunologia , Vaccinia virus/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Enzimas de Restrição do DNA , Imunofluorescência , Vetores Genéticos , Plasmídeos , Regiões Promotoras Genéticas , Coelhos , Timidina Quinase/genética , Vaccinia virus/genética , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/isolamento & purificação
18.
J Gen Virol ; 45(3): 683-701, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-232137

RESUMO

Orthopoxvirus DNA from representative strains of rabbitpox, vaccinia, monkeypox, variola, cowpox and ectromelia viruses was analysed by cleavage with restriction endonucleases HindIII, XhoI or SmaI. Genome mol. wt. vary from about 120 x 10(6) for rabbitpox to about 145 x 10(6) for cowpox. Physical maps of cleavage sites are similar and characteristic for strains of the same Orthopoxvirus type. The distribution of HindIII sites suggests that an internal region of mol. wt. about 30 x 10(6) is highly conserved between Orthopoxvirus genomes although some type-specific differences occur within this region, especially with strains of ectromelia virus. Conservation of internal sequences is less marked following analysis with XhoI although cleavages within this central region of particular genomes appear to represent a subset of preferred sites. Endonuclease SmaI cleaves exceptionally infrequently and distinguishes variola, monkeypox, vaccinia, cowpox or ectromelia viruses. Type specific differences result largely from extensive, near terminal variations in length and sequence. Representative Orthopoxvirus genomes have rapidly renaturing terminal restriction fragments confirming the presence of near terminal, covalent cross-links. Terminal restriction fragments from the same or different genomes generally cross hybridize indicating the presence of near terminal repetitions of mol. wt. up to 6 x 10(6) and which share at least a subset of common sequences. Variola strains however, appear to lack such sequences from one specific terminus which maps shorter than that of related viruses.


Assuntos
DNA Viral/análise , Genes Virais , Poxviridae/análise , Sequência de Bases , Enzimas de Restrição do DNA/metabolismo , Vírus da Ectromelia/análise , Monkeypox virus/análise , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Vaccinia virus/análise , Vírus da Varíola/análise
19.
J Gen Virol ; 70 ( Pt 3): 729-34, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2543757

RESUMO

Epstein-Barr virus (EBV) membrane antigen glycoproteins gp340 and gp220 are encoded by a single gene. We have inserted this gene into a bovine papillomavirus (BPV) vector and expressed gp340/220 in mammalian cells under the control of the mouse metallothionein promoter. The proteins produced were of similar Mr, showed similar antigenic specificity and were transported to the same subcellular location as the authentic gp340/220. The inclusion of heavy metal ions in the medium had no effect on the levels of gp340/220, which were approximately the same as those found in standard EBV-transformed lymphoblastoid cell lines, e.g. B95-8. Cells that expressed gp340/220 were selected by several rounds of fluorescence-activated cell sorting, but on passage they rapidly lost the ability to express this glycoprotein. In contrast to this we found that BPV-transformed cells expressing a truncated version of gp340/220 still produced it at significant levels after extended passage.


Assuntos
Antígenos Virais/genética , Papillomavirus Bovino 1/genética , Vetores Genéticos , Herpesvirus Humano 4/genética , Glicoproteínas de Membrana/genética , Papillomaviridae/genética , Proteínas do Envelope Viral/genética , Animais , Antígenos de Superfície/genética , Papillomavirus Bovino 1/imunologia , Células Cultivadas , DNA Viral/genética , Fibroblastos/imunologia , Fibroblastos/microbiologia , Regulação da Expressão Gênica , Genes Virais , Herpesvirus Humano 4/imunologia , Glicoproteínas de Membrana/imunologia , Camundongos , Plasmídeos , Recombinação Genética , Proteínas do Envelope Viral/imunologia
20.
J Hyg (Lond) ; 89(3): 373-81, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6296224

RESUMO

The white pock variant of cowpox virus shows limited growth in chick embryo fibroblasts maintained in arginine-deprived culture medium. Since these conditions inhibit the growth of parental virus, there is a marked increase in the frequency of the white variant in the virus population recovered after passage in the absence of arginine. The variants generated in this system have been characterized by restriction endonuclease analysis of virus DNA in the total DNA recovered from infected cell cultures. Such analysis shows that the white variants arise as deletion mutants of the parental virus, but there was considerable heterogeneity in the restriction patterns of different isolates examined shortly after their generation. Further passage selected white cowpox virus populations with a stable genome configuration comparable with the DNA of pock-purified white variants.


Assuntos
Vaccinia virus/genética , Animais , Arginina/deficiência , Células Cultivadas , Embrião de Galinha , Meios de Cultura , Enzimas de Restrição do DNA , DNA Viral/genética , Mutação , Replicação Viral
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