| physical and biological properties of dengue-2 virus and associated antigens. | dengue virus suspensions from mouse brain and cell culture were fractionated into three components by rate zonal centrifugation in sucrose gradients. infectious virus sedimented in a single zone and possessed hemagglutinating (ha) and complement fixing (cf) activity. electron micrographs showed the virion to be a spherical particle 48 to 50 nm in diameter with 7-nm spherical structures on its surface. buoyant density in cscl of virions from mouse brain was estimated at 1.22 g/cm(3) and from cell ... | 1970 | 4195055 |
| the influence of higher temperature on dengue-2 virus infected c6/36 mosquito cell line. | dengue-2 virus infection of c6/36 cells was studied at 28 and 37 degrees c. in infected cells maintained at 28 degrees c, syncytial development was seen on day 4 postinfection, whereas at 37 degrees c, extensive syncytial development was seen by 32 h. extracellular virus titre was found to correlate with the cytopathic changes. nine dengue-2 virus specified proteins were observed in polyacrylamide analyses of cytoplasmic extracts of c6/36 infected cells. all the proteins were observed, although ... | 1987 | 2891426 |
| sequential immunization procedure against group b arboviruses using living attenuated 17d yellow fever virus, living attenuated langat e5 virus, and living attenuated dengue 2 virus (new guinea c isolate). | | 1973 | 4352231 |
| variation in dengue type 2 viruses isolated in bangkok during 1980. | dengue type-2 viruses isolated in metropolitan bangkok during 1980 (bangkok/80) were characterized by oligonucleotide fingerprinting, restriction enzyme (re) mapping and antigenic analysis using monoclonal antibody probes. of 10 isolates analysed by oligonucleotide fingerprinting, nine were very closely related, showing 72.5% to 91.4% oligonucleotide homology. one isolate (d80-141) produced a distinctly different fingerprint (55.7% to 58.0% homology) and was less related to other bangkok/80 deng ... | 1988 | 3351477 |
| nucleotide sequence of the envelope glycoprotein gene of a dengue-2 virus isolated during an epidemic of benign dengue fever in tonga in 1974. | | 1990 | 2216784 |
| cloning of dengue virus type 2 by the direct fluorescent antibody technique. | | 1973 | 4589217 |
| morphology and development of dengue-2 virus employing the freeze-fracture and thin-section techniques. | | 1974 | 4591567 |
| detection of dengue viral rna in mosquito vectors by mixed phase and solution hybridization. | a mixed phase hybridization technique was developed to detect dengue virus type 2 (den-2) rna in pools of infected aedes albopictus mosquitoes using radiolabelled rna probes. this technique used a guanidine thiocyanate extraction procedure to simplify analyte preparation. the probes contained sequences complementary to portions of the ns-1 or ns-5 genes of the den-2 viral genome. one infected mosquito in a pool of 25 could be detected in approximately 48 h. rnas from den serotypes 1-4 were extra ... | 1990 | 2402251 |
| serologically defined linear epitopes in the envelope protein of dengue 2 (jamaica strain 1409). | antisera from dengue patients and dengue virus infected rabbits recognized octapeptides corresponding to linear amino acid sequences in the envelope protein of dengue 2 (jamaica 1409). although no peptide was recognized by sera from all dengue infected hosts, two peptides (216lplpwlpg223 and 448fsgvswtm455) were recognized by sera from all dengue 2 infected rabbits. one of these 448fsgvswtm455 was also recognized by sera from both the dengue 2 patients tested. no peptides were identified which r ... | 1989 | 2473720 |
| recovery of dengue-2 virus from aedes aegypti in colombia. | | 1973 | 4745238 |
| dengue virus-specific human t cell clones. serotype crossreactive proliferation, interferon gamma production, and cytotoxic activity. | the severe complications of dengue virus infections, hemorrhagic manifestation and shock, are much more commonly observed during secondary infections caused by a different serotype of dengue virus than that which caused the primary infections. it has been speculated, therefore, that dengue hemorrhagic fever (dhf) and dengue shock syndrome (dss) are caused by serotype crossreactive immunopathological mechanisms. we analyzed clones of dengue serotype crossreactive t lymphocytes derived from the pb ... | 1989 | 2475573 |
| dengue virus plaque development in simian cell systems. i. factors influencing virus adsorption and variables in the agar overlay medium. | chemical and physical variables influencing the plaquing of all dengue serotypes in two simian cell systems were studied. calf serum in the nutrient overlay may be replaced by mouse ascitic fluid or bovine plasma albumin when employing the rhesus monkey kidney llc-mk(2) cell system for plaquing all dengue serotypes. doubling the serum concentration in the overlay had little effect in modifying dengue types 1, 2, 3, and 4 plaque titers. newborn agamma, 4-week-old and 8-week-old calf serum gave co ... | 1970 | 4987200 |
| comparison of three methods used to isolate dengue virus type 2. | during the 1969 dengue epidemic in puerto rico, human sera and aedes aegypti mosquitoes were collected for virus isolation and identification. three methods of isolation were used and compared. in the first method, we inoculated newborn mice by the intracranial route, noted any signs of illness, and serially passed specimens in mice until virus was isolated. in the second method, we inoculated tube cultures of llc-mk(2) cells, noted any cytopathic effect (cpe), and assayed fluids for virus by pl ... | 1971 | 5002896 |
| stimulation of plasminogen activator inhibitor activity in human monocytes infected with dengue virus. | human monocytes, in an essentially serum-free culture medium, were infected with dengue 2 virus in the presence of sub-neutralizing concentrations of antibody. changes in procoagulant activity (pca), in the plasminogen activator urokinase (uk), and the plasminogen activator inhibitor-2 (pai-2) were quantitated. one day after exposure to dengue virus, the cell-associated pai-2 activity in the infected monocytes was 562 +/- 9 mu/10(6) cells (mean +/- se) compared to 206 +/- 56 mu/10(6) cells for u ... | 1989 | 2492775 |
| effect of dengue virus on procoagulant and fibrinolytic activities of monocytes. | some of the fibrinolytic and coagulation enzymes that monocytes produce are urokinase, a plasminogen activator (pa); a pa-specific inhibitor (pai); and procoagulant activity (pca), which has been characterized as tissue factor. dengue infection in vivo is restricted to monocytes; however, it is unknown if dengue-infected monocytes undergo alterations in the production of pa, pai, and pca. this issue was addressed in studies in which monocytes were infected in vitro with dengue 2 virus in serum-f ... | 1989 | 2501855 |
| [effectors of in vivo delayed hypersensitivity in experimental flavivirus infections and vaccination against tick-borne encephalitis in mice]. | the development of experimental infections caused by tick-borne encephalitis (tbe) virus, langat virus and dengue virus type 2 in mice or the immunization of these animals with live yellow fever vaccine (prepared from strain 17d) and inactivated tbe vaccine were accompanied by the formation of delayed hypersensitivity (dh) to viral antigens, determined in vivo. in experimental tbe infection the effectors of dh were identified as t-lymphocytes whose action was specific and followed the rule of h- ... | 1984 | 6098109 |
| evidence that maternal dengue antibodies are important in the development of dengue hemorrhagic fever in infants. | to establish the role of maternal dengue-specific antibodies in the development of dengue hemorrhagic fever and dengue shock syndrome caused by dengue 2 virus in infants, we examined sera from mothers of infants and toddlers with dengue hemorrhagic fever or dengue shock syndrome and mothers of infants with pyrexia of unknown origin. the mean titers of hemagglutination inhibition, neutralization, and infection-enhancing activities against dengue 2 virus were not statistically different among the ... | 1988 | 3354774 |
| in vivo inhibition by intact mouse serum of the activity of the flavivirus-induced t-suppressors of autoreactive t-lymphocytes. | in the serum of healthy mice a factor was found inhibiting the in vivo effect of t-suppressors of autoreactive t-lymphocytes (tsart1) induced in mice by tick-borne encephalitis (tbe) virus, langat virus, dengue virus type 2 (d2) and attenuated strain 17d of yellow fever virus. activity of the serum factor (s) was demonstrated providing that the tsart1 had h-2 antigens completely or partially identical with the h-2 antigens of serum donors. the activity was not connected with destruction of tsart ... | 1984 | 6147997 |
| enhancement of dengue virus infection in monocytes by flavivirus antisera. | enhanced dengue 2 virus (d2v) infection in suspension cultures of human peripheral blood mononuclear phagocytes (pbl) produced by subneutralizing concentrations of dengue antisera has been described previously. in this study, the enhancement phenomenon was found to be a general property of representative flavivirus antisera. all except one of 24 antisera, which had been raised by 1-3 injections of flaviviruses in rabbits, enhanced the growth of dengue 2 virus in human pbl. flavivirus antisera sh ... | 1980 | 6157332 |
| serological evidence of dengue fever among refugees, hargeysa, somalia. | epidemics of a malaria-like illness affected several thousand residents of the dam camp, a refugee camp near hargeysa in somalia, during 1985, 1986, and 1987. the disease was characterized by fever, chills, sweats, headache, back and joint pains for as long as 10 days in some patients. blood smears from acutely ill patients were negative for malaria. of 28 acute and 10 convalescent sera tested by the indirect fluorescent antibody (ifa) and by the hemagglutination inhibition (hi) tests, all were ... | 1989 | 2600591 |
| detection of some dengue-2 virus antigens in infected cells using immuno-microscopy. | immunoelectron microscopy was used to detect the distribution of some dengue-2 virus proteins in infected vero and aedes albopictus (c6/36) cells. it was found that the envelope protein (gp 60) was located in clumps on the surface of plasma membrane, and accumulated very little in the infected cytoplasm. however no envelopment of dengue-2 virus nucleocapsids through the plasma membranes was observed. in contrast, the ns 3 (p 67) protein was distributed throughout the whole cytoplasm. no specific ... | 1989 | 2650656 |
| analysis of 17d yellow fever virus envelope protein epitopes using monoclonal antibodies. | sixteen monoclonal antibodies that reacted with the envelope glycoprotein (e) of 17d vaccine strain yellow fever virus (17d yf), including two antibodies produced against dengue 2 virus, were used in a solid phase competitive binding assay (cba) to define spatial relationships among antigenic determinants on 17d yf e. the antibodies showed yf strain, type or flavivirus group specificities and nine epitopes were identified on 17d yf e by patterns of neutralization, haemagglutination inhibition an ... | 1984 | 6208313 |
| effect of adjuvant vaccines on dengue virus type 2 immune ascitic fluid production. | in a comparison of dengue type 2 immune mouse ascitic fluid immunization schedules, a schedule in which adjuvant vaccines were not used produced neutralizing antibody titers that were specific and a mouse mortality rate that was lower, resulting in a greater yield of ascitic fluids. in the schedules in which emulsified adjuvant vaccines were used, the quality of the emulsion had little effect on antibody titer produced. | 1985 | 3980697 |
| dengue virus induced polypeptide synthesis. brief report. | dengue 2 virus polypeptide synthesis was investigated in bhk21 cells. nine or ten virus induced polypeptides were identified, three of which are glycoproteins as demonstrated by tunicamycin treatment of infected cells. we performed pulse chase experiments, experiments with amino-acid analogs, protease inhibitors or pactamycin treatment of infected cells, to determine whether or not large polypeptide processing occurs. in some of these experiments a large polypeptide (p 130) was immunoprecipitate ... | 1985 | 4015406 |
| quantity of dengue virus required to infect rhesus monkeys. | as part of a dengue vaccine study, it was necessary to determine how much virus was required to infect rhesus monkeys. serial dilutions of dengue 2 and 4 viruses were inoculated subcutaneously into groups of five monkeys and seroconversions determined on days 30 and 60 post-inoculation. the viruses were also titrated simultaneously in llc-mk2 cells and mosquitoes. it was calculated that 9.5 mosquito infectious doses 50 (mid50) of dengue 2 virus and 22 mid50 of dengue 4 virus were required to inf ... | 1985 | 2860743 |
| dengue 2 virus envelope protein expressed by a recombinant vaccinia virus fails to protect monkeys against dengue. | a cdna copy of the dengue (den) 2 virus genome region encoding the virion capsid, membrane and envelope structural proteins has been inserted into vaccinia virus (vv) dna under the control of its 11k late promoter. the den-2 envelope protein was expressed and processed in cells infected with the vv recombinant (vv/d2s). no den-2 virus antibody response was detected in mice, hamsters or monkeys vaccinated with vv/d2s. furthermore, a viraemia was observed in recombinant-vaccinated monkeys after ch ... | 1988 | 3404119 |
| the quantitative kinetic study of dengue viral antigen by flow cytometry. i. an in vitro study. | a system effective in the early diagnosis of dengue virus infection was developed. the time course kinetics of dengue virus type 2 (d-2) antigen in vitro were analyzed by flow cytometry. early profiles of d-2 were also studied quantitatively through this method of analysis. the early events of host cell and virus interaction were investigated: attachment, internalization and replication. from these early profiles, the time at which new viral synthesis was detectable differed with each individual ... | 1985 | 4036316 |
| host-induced modification of dengue-2 virus surface antigens in aedes albopictus cells. | | 1973 | 4132537 |
| replication of dengue virus type 2 in aedes albopictus cell culture. | the replication of type 2 dengue (d-2) virus in aedes albopictus (aal) mosquito cell cultures differed from that in vertebrate (llc-mk2) rhesus monkey kidney cells. virus readily replicated in aal cells at either 30 or 37 c, but had no apparent effect on the host cell. persistent infection was established with continual virus production for at least 6 months, although the virulence of progeny virus for both suckling mice and llc-mk2 cells became attenuated. density gradient analysis of infected ... | 1973 | 4201188 |
| detection of dengue virus type 2 in aedes albopictus by nucleic acid hybridization with strand-specific rna probes. | a molecular hybridization technique with radiolabeled, strand-specific rna probes was developed to detect dengue virus type 2 rna in pools of infected aedes albopictus mosquitoes. one infected mosquito in a pool of 25 could be detected, corresponding to a dengue virus type 2 titer of 2.75 log10 50% tissue culture infectious doses. | 1988 | 3281980 |
| seroepidemiologic study of arbovirus infections in the north-east and south of thailand. | blood specimens were collected from villagers in khon-kaen province, in the north-eastern region, and in songkhla province, in the southern region of thailand in the pre- and post-epidemic seasons of hemorrhagic fever. the hemagglutination inhibition antibody titers of the specimens were measured against dengue virus type 2, type 4, japanese encephalitis virus and chikungunya virus. in general, khon-kaen villagers showed higher levels of hi antibodies against these arboviruses than songkhla vill ... | 1974 | 4464834 |
| [dengue 2 in eastern senegal: serologic survey in simian and human populations. 1974-85]. | after the previously reported isolations of dengue 2 virus in eastern senegal in 1974 and 1981-1982, a retrospective serological study on simian and human populations was carried out in the same area. we investigated 1,095 simian sera collected at regular intervals between 1974 and 1984 from wild caught monkeys and 1,783 human sera from young children less than 11 years old collected during punctual surveys after the rainy season from 1976 to 1985. sera were tested using hai test, cf test and fo ... | 1986 | 3769119 |
| transovarial transmission of dengue 2 virus by aedes aegypti in nature. | dengue 2 virus was recovered from three of 123 pools of naturally infected aedes aegypti larvae (6,200 insects) collected from water containers in rangoon. the virus was also isolated from two of 76 pools (7,730 mosquitoes) of male ae. aegypti, collected as larvae and reared in the laboratory to adults. minimum field infection rates among these two groups of mosquitoes were 1:2,067 and 1:3,865, respectively. insect pools were inoculated into toxorhynchites splendens mosquitoes and dengue viral a ... | 1983 | 6859404 |
| the mechanism of cross-protection afforded by dengue virus against west nile virus in hamsters. | the protection afforded by similar concentrations of different dengue virus serotypes against a subsequent challenge of west nile virus was studied in hamsters. the new guinea c strain of dengue 2 virus gave the best protection. it was found that the anamnestic neutralizing antibody response induced by the challenge west nile virus against west nile virus in hamsters, previously immunized with dengue 2 virus, might play a major role in the cross-protection observed in this system. | 1972 | 4509639 |
| partial sequence analysis of cloned dengue virus type 2 genome. | dengue virus (den) is a member of flaviviruses and contains a single, (+)-strand rna of approx. 11 kb. complementary dna copy of the rna was synthesized using reverse transcriptase and oligo(dt) as primer. the double-stranded dna copy was cloned at the psti site of puc13'-1 vector and was used to transform escherichia coli jm83. eleven transfomants were found to contain den insert as screened by colony hybridization. three clones were chosen for further characterization by nucleotide (nt), seque ... | 1986 | 3803928 |
| alterations in thrombopoiesis in patients with thrombocytopenia produced by dengue hemorrhagic fever. | the causes of thrombocytopenia, one of the most dangerous symptoms in the course of dengue hemorrhagic fever (dhf), are not yet clear. we studied patients with dhf (dengue virus type 2), grouped according to days of illness, platelet counts, serum thrombopoietin (tpo) levels, and bone marrow differential counts. during the thrombocytopenic phase of disease (3rd-8th days) the tpo levels were not increased in spite of low platelet counts. beginning from the 6th-7th day in some patients, a rapid in ... | 1986 | 3808936 |
| synergistic interactions of anti-ns1 monoclonal antibodies protect passively immunized mice from lethal challenge with dengue 2 virus. | non-neutralizing, serotype-specific anti-ns1 monoclonal antibodies partially protected passively immunized mice from lethal dengue 2 virus intracerebral challenge. there was no apparent correlation between complement-fixing activity and protective capacity among individual anti-ns1 monoclonal antibodies. immunization with specific combinations of non-protective or partially protective antibodies resulted in prolonged survival or reduced mortality. solid protection, equal to that achieved after i ... | 1988 | 3404125 |
| dengue virus infection of mice: morphology and morphogenesis of dengue type-2 virus in suckling mouse neurones. | in dengue type-2 virus-infected neurones of suckling mice, formation of single-membrane vesicles is observed in the distended cisternae of the endoplasmic reticulum mostly of the perinuclear zone around 72 h after inoculation. electron-dense 50-nm virus particles are arranged in chains in these distended cisternae; some form small crystalloid aggregates. aberrant particles of different shapes are also seen in the distended cisternae about the same time that the virus particles appear. parallel f ... | 1973 | 4594115 |
| dengue virus multiplication in cultures of mouse peritoneal macrophages: effects of macrophage activators. | dengue-2 virus multiplied in cultures of methylcellulose-induced peritoneal macrophages of balb/c mice. the in vitro-cultivated macrophages from dengue-1 virus-immune mice produced larger amounts of dengue-2 virus than did those from nonimmune controls. the effect of macrophage activators was examined by using nonimmune macrophages. enhanced virus production was demonstrated in cultures of macrophagges pretreated with phytohemagglutinin (pha) or bacterial lipopolysaccharide (lps). the number of ... | 1982 | 7176969 |
| the attenuation of the 26th mouse brain passage of new guinea c strain of dengue 2 virus for use in the sequential immunization procedure against group b arboviruses. | | 1973 | 4630883 |
| protection of mice against dengue 2 virus encephalitis by immunization with the dengue 2 virus non-structural glycoprotein ns1. | immunization of mice with the dengue 2 virus (den 2)-specified non-structural protein ns1 provided significant protection against intracerebral challenge with the virus in the absence of detectable neutralizing or other anti-virion antibody. ns1, purified from lysates of infected vero cells by immunoaffinity chromatography, expressed an antigenic site(s) common to each of the four den serotypes, and hyperimmunization of rabbits with ns1 stimulated production of complement-fixing (cf) antibody wi ... | 1987 | 3819700 |
| proceedings: cytopathic effect of dengue-2 virus on an established mosquito cell-line. | | 1974 | 4818653 |
| rapid complement fixation technique for estimating complement-fixing antigen elution profiles of viruses from gel filtration columns. | the complement fixation elution profiles of dengue-2 virus-infected suckling mouse brain supernatant fluids from sephadex g-200 columns were compared by the antigen end-point titration procedure and by a complement dilution technique. the latter technique was found to be a quick method for approximating the complement-fixing antigen in eluates. | 1972 | 5057370 |
| dengue virions and antigens in brain and serum of infected mice. | the temporal relationships of the production of infectious dengue-2 virus and its antigens were investigated in intracerebrally infected suckling mice. infectious virus, a slowly sedimenting noninfectious hemagglutinin (sha), and a noninfectious soluble complement-fixing antigen (scf) were found in the brain. serum contained high concentrations of scf antigen relative to infectivity when compared to scf to infectivity ratios in the brain. degradation of virions by tween-80 and ether produced two ... | 1970 | 5497897 |
| dengue-2 virus in kenya. | | 1982 | 6123900 |
| identification of distinct antigenic determinants on dengue-2 virus using monoclonal antibodies. | monoclonal antibodies directed against antigenic determinants of the new guinea c strain of dengue-2 virus were obtained from lymphocyte hybridomas produced by fusing immune mouse lymphocytes with mouse myeloma cells. hybridoma cell culture supernatants were screened by using a radioimmunoassay employing detergent-solubilized dengue-2 infected cell antigens. monoclonal antibodies in ascitic fluids induced by 22 selected hybridomas were characterized by the hemagglutination-inhibition, plaque red ... | 1982 | 6177259 |
| immunization with a live attenuated dengue-2-virus candidate vaccine (16681-pdk 53): clinical, immunological and biological responses in adult volunteers. | a live dengue-2 (den-2) candidate vaccine (strain 16681-pdk 53), attenuated by passage in primary dog kidney cells, was tested in ten adult volunteers for evaluation of the safety, infectivity and immunogenicity of a dose of 1.9-2.7 x 10(4) plaque-forming units. five of the volunteers were nonimmune to either dengue or japanese encephalitis (je) viruses; the other five were nonimmune to dengue but immune to je. after receiving 1.0 ml of the vaccine subcutaneously, all ten volunteers developed ne ... | 1987 | 3496985 |
| dengue virus type 2 vaccine: reactogenicity and immunogenicity in soldiers. | a live dengue virus type 2 (dengue-2) vaccine (pr-159/s-1) was tested for reactogenicity and immunogenicity in a placebo-controlled, double-blind clinical trial involving 98 soldiers. seroconversion rates based on the development of neutralizing antibody to dengue-2 were 90% in 70 recipients with immunity to yellow fever and 61% in 28 vaccinees without such immunity (p less than .01). peak titers of neutralizing antibody were three times higher in recipients with antibody to yellow fever virus a ... | 1984 | 6376649 |
| lack of augmenting effect of interferon-gamma on dengue virus multiplication in human peripheral blood monocytes. | the effect of interferon-gamma (ifn-gamma) on dengue virus multiplication in human peripheral blood monocytes was investigated. enriched monocytes were treated with ifn-gamma and then infected with dengue virus type 2 either directly or in the presence of optimal infection-enhancing levels of antibodies. pretreatment of monocytes from dengue-immune donors with 100 iu/ml of ifn-gamma caused 12- to 97-fold and 13- to 137-fold reduction of virus yields at 24 hr after infection in the absence and pr ... | 1995 | 7536230 |
| the vector competence of colonized aedes (stegomyia) katherinensis for dengue-2 virus. | colonized aedes (stegomyia) katherinensis mosquitoes from australia were infected with the pr-159 strain of dengue-2 virus using a membrane feeding technique and by intrathoracic inoculation. virus replication to low levels was detected when mosquitoes infected by both routes were assayed using the virus-sensitive ae. pseudoscutellaris (lstm-ap-61) mosquito cell line in a microculture system. analysis by indirect immunofluorescence revealed the expected 100% infection rates in inoculated mosquit ... | 1984 | 6398536 |
| [isolation of dengue virus type 2 from the serum of patients using the suckling mouse and cultured llcmk2 cells]. | | 1984 | 6438733 |
| genetic variation among dengue 2 viruses of different geographic origin. | genetic variation in dengue 2 isolates from various geographic areas was examined by oligonucleotide fingerprinting of the 40 s genome rna. oligonucleotide maps of geographically isolated and epidemiologically unrelated viruses were very distinct. direct comparison of the oligonucleotide map of the dengue 2 prototype new guinea 2 virus, isolated in 1944, with the fingerprints of more recent isolates from the south pacific indicated that the genome of dengue 2 virus had undergone extensive change ... | 1983 | 6612990 |
| effect of dengue virus infection on fc-receptor functions of mouse macrophages. | fc-receptor-mediated attachment and ingestion of opsonized sheep erythrocytes (ea) by the macrophages of spleen and peritoneal cavity were studied during dengue virus type 2 (dv) infection of swiss albino mice. following intracerebral inoculation, virus antigen could be demonstrated by immunofluorescence in the splenic macrophages from day 4 and in peritoneal macrophages from day 5 post-infection, with a higher number of positive cells discernible on the 7th and 8th days. the virus could be isol ... | 1983 | 6644274 |
| dengue 2 vaccine: dose response in volunteers in relation to yellow fever immune status. | a live dengue 2 vaccine was tested in 38 volunteers in an evaluation of the safety, infectivity, and immunogenicity of doses of 10(1.8)-10(5.5) plaque-forming units. twenty yellow fever-immune and 18 yellow fever-nonimmune individuals received 0.5 ml of vaccine sc. immunization was dose related in yellow fever-immune volunteers, with a 50% immunizing dose of 10(3.3) plaque-forming units. in the group not immune to yellow fever, some but not all recipients of each vaccine dilution were immunized, ... | 1983 | 6655288 |
| association between ns3 and ns5 proteins of dengue virus type 2 in the putative rna replicase is linked to differential phosphorylation of ns5. | dengue virus type 2, a member of the family flaviviridae, encodes a single polyprotein precursor consisting of 3391 amino acids residues that is processed to at least 10 mature proteins by host and viral proteases. the ns3 protein contains a domain commonly found in cellular serine proteinases that in cooperation with ns2b is involved in polyprotein processing. in addition, ns3 and ns5 proteins contain conserved motifs found in several rna helicases and rna-dependent rna polymerases, respectivel ... | 1995 | 7642575 |
| treatment of intracranial dengue virus infections in mice with a lipophilic derivative of ribavirin. | rimantadine, ribavirin, and 6-mercapto-9-(tetrahydro-2-furyl)purine, administered intraperitoneally every 8 h for 7 days starting minutes after virus challenge, had no effect on survival and mean survival time of balb/c mice inoculated intracranially with dengue virus type 2. in contrast, intraperitoneal treatment with ribavirin 2',3',5'-triacetate, a lipophilic analog of ribavirin, effected significant increases in both mean survival time and survival rate, suggesting that ribavirin 2',3',5'-tr ... | 1983 | 6684897 |
| studies on dengue 2 virus infection in cyclophosphamide-treated rhesus monkeys. | dengue 2 virus (d2v) replication has been demonstrated in cultured primate mononuclear phagocytes, mitogen treated lymphocytes and lymphoblastoid cells. to determine which of these cell types might play an important role in sustaining infection in vivo, nine rhesus monkeys were immunosuppressed with cyclophosphamide and then infected with d2v. maintenance dose which held total white blood cell counts to less than 3000/mm3 ablated both primary and secondary antibody responses. six successfully im ... | 1980 | 6770237 |
| blood-feeding behavior of dengue-2 virus-infected aedes aegypti. | this study was designed to determine if infection of aedes aegypti with dengue-2 virus affects the ability of the mosquito to efficiently locate and imbibe blood from an uninfected host. previous studies suggest that some parasites manipulate their arthropod host to increase the probability of transmission by interfering with blood-feeding efficiency. we found no evidence that dengue-2 virus infection by intrathoracic inoculation impaired the blood-feeding efficiency of ae. aegypti. we speculate ... | 1995 | 7694963 |
| comparison of p388d1 mouse macrophage cell line and human monocytes for assay of dengue-2 infection-enhancing antibodies. | tissue culture-adapted dengue 2 virus (den 2), strain 16681, exhibits antibody-dependent enhancement of infection (ade) in p388d1 cells, a mouse macrophage-like cell line. ade is dependent upon maintaining den 2 multiplicity of infection at between 0.1 and 0.001, and can be simply measured in multi-well plastic plates. the assay uses either trypsinized or non-trypsinized p388d1 cells at 5 x 10(5) cells per ml, an appropriate dilution of den 2 virus, and a source of antibody, and is most convenie ... | 1983 | 6824121 |
| the effect of multiple host contacts on the infectivity of dengue-2 virus-infected aedes aegypti. | this study was designed to determine if transmission rates for dengue-2 virus by aedes aegypti are altered by mosquitos probing a host for blood or imbibing blood prior to attempting transmission. aedes aegypti is known to contact multiple hosts during each egg-laying cycle and multiple host contacts might diminish the amount of virus in infected mosquito's salivary glands or ducts and render them functionally uninfective. probing a host 5, 10, or 20 consecutive times did not significantly alter ... | 1995 | 7707190 |
| plasma membrane-acting drugs inhibit the effect of dengue virus-induced cytotoxic factor. | our earlier studies reported that the cytotoxic factor (cf) produced in the spleen of dengue virus type 2-infected mice killed the lymphoid cells of many species of animals and induced normal mouse splenic and peritoneal macrophages to produce a cytotoxin (cf2). in the present study, it has been observed that pretreatment of target cells with cell plasma membrane stabilizers--2,4-dinitrophenol, ouabain and reduced glutathione--prevents the cytotoxicity of cf and blocks the production of cf2, but ... | 1983 | 6870195 |
| enhancement of dengue virus type 2 replication in mouse macrophage cultures by bacterial cell walls, peptidoglycans, and a polymer of peptidoglycan subunits. | the effects of bacterial cell walls, peptidoglycans, and a water-soluble polymer of peptidoglycan subunits on dengue virus type 2 replication in cultured mouse peritoneal macrophages were studied. pretreatment of macrophage cultures with all of test cell walls isolated from seven bacterial species for 3 days significantly enhanced the virus production in the cultures. peptidoglycans prepared from four of the above cell walls also exerted the virus production-enhancing effects in a similar manner ... | 1983 | 6874066 |
| dengue in the seychelles. | epidemics of dengue-like illness occurred in the seychelles from december 1976 to april 1977 and from december 1978 to january 1979. dengue 2 virus was isolated from individuals who had been in the seychelles in 1977. from february to april 1979, sera were collected from outpatients in mahé, seychelles, who had not previously been hospitalized with a dengue-like illness. results of neutralization tests with these sera indicated that prevalence rates for the four dengue viruses were between 81% a ... | 1981 | 6976229 |
| infection of young adult mice with dengue virus type 2. | young adult female mice, five to six weeks old, were injected intraperitoneally with 2.5 x 10(6.3) ld50 of dengue-2 virus, new guinea c strain. the mice were killed on day 1, 2, 3, 4, 5, 6, 7, 10, 14, 21, 28, and 35 respectively. by means of the immunofluorescent antibody technique, viral antigen appeared as irregular granules in the reticuloendothelial cells of liver, lymph nodes and spleen of infected mice on the first day after inoculation and then diminished. from the fifth to sixth day of i ... | 1981 | 7036427 |
| depressed macrophage functions in dengue virus-infected mice: role of the cytotoxic factor. | dengue virus type 2 (dv) infection causes immunosuppression in mice. since macrophages are crucial for immune response, we have studied their functions in this condition and report our findings here. it was observed that in dv-infected mice the phagocytosis of neutral-red and latex particles by splenic and peritoneal-cavity macrophages was significantly reduced (p less than 0.001) from days 3 to 10 after inoculation. similarly the migration of splenic and peritoneal macrophages on a glass surfac ... | 1982 | 7073959 |
| suppression of dengue virus replication in vitro by rimantadine hydrochloride. | the effects of rimantadine on dengue virus replication were examined in a variety of tissue culture systems. the growth of dengue virus type 2 in human peripheral blood leukocytes (pbl) was completely suppressed when rimantadine was included in the culture medium at a concentration of 25 microgram/ml. similarly, rimantadine caused a significant inhibition of dengue virus replicaton in cultures of rhesus monkey pbl. addition of drug into virus-infected llc-mk2 cell cultures caused a decrease in t ... | 1981 | 7212165 |
| in vitro virulence marker: growth of dengue-2 virus in human leukocyte suspension cultures. | we wished to find a simple, biologically relevant method to evaluate the virulence of dengue viruses for human beings. since cells of mononuclear phagocyte lineage may be important sites of dengue infection in primates, we evaluated the permissiveness of these cells to dengue virus as a correlate of virus virulence. two wild-type, large-plaque, monkey-virulent dengue-2 virus strains and two small-plaque, monkey-avirulent dengue-2 virus strains were evaluated for their ability to replicate in hum ... | 1981 | 7216440 |
| dengue-2 vaccine: virological, immunological, and clinical responses of six yellow fever-immune recipients. | six male volunteers, previously immunized with yellow fever vaccine, were inoculated subcutaneously with a live, attenuated dengue-2 virus (pr-159/s-1) candidate vaccine. five recipients developed viremia 8 or 9 days after vaccination, which lasted 1 to 10 days. the onset of viremia was followed by fever in three people, transient leukopenia in four, and an erythematous rash in one. one volunteer developed an oral temperature of 38.8 degrees c with headache, myalgia, fatigue, and photophobia sug ... | 1981 | 7216469 |
| precise location of sequential dengue virus subcomplex and complex b cell epitopes on the nonstructural-1 glycoprotein. | the reactions of a panel of 34 mouse monoclonal antibodies (mabs) specific for the dengue-2 virus nonstructural-1 glycoprotein (ns1), were analysed using 174 overlapping synthetic nonameric peptides covering the entire sequence. using this methodology, four epitopes were identified. one pair of mabs, which defined a dengue-2/4 virus subcomplex epitope (24c: amino acids 299-309) using native ns1 proteins, showed the same reaction pattern with synthetic peptides containing the corresponding ns1 se ... | 1994 | 7944953 |
| inhibition of dengue virus replication by amantadine hydrochloride. | the effect of amantadine hydrochloride (1-adamantanamine hydrochloride) on dengue virus replication was examined in vitro. amantadine decreased the titers of all four types of dengue viruses grown in llc-mk2 cells by greater than 90% at concentrations of 50 micrograms/ml. there was no evidence for any cytopathic effect of the drug at concentrations less than 100 micrograms/ml. studies of the time of addition showed that the antiviral effect was maximal when drug was added to virus cultures immed ... | 1980 | 7416739 |
| antibody-enhanced binding of dengue-2 virus to human platelets. | the mechanisms underlying severe thrombocytopenia in dengue hemorrhagic fever/dengue shock syndrome (dhf/dss) are not completely understood. we present here the first evidence that dengue type 2 virus binds to human platelets only in the presence of virus-specific antibody, supporting a role for immune-mediated clearance of platelets in the pathogenesis of thrombocytopenia in dhf/dss. antibody-enhanced binding of virus of platelets was also demonstrated with a panel of eight murine monoclonal an ... | 1995 | 7483271 |
| use of a flavivirus rna-dependent rna polymerase assay to investigate the antiviral activity of selected compounds. | we have developed an assay using flavivirus rna-dependent rna polymerase to test the inhibitory activity of potential antiviral agents. the effects of antiviral agents on rna synthesis were examined in this assay using extracts of vero cells infected with dengue virus type 2 or kunjin virus. several different classes of known polymerase inhibitors were tested. the synthesis of double-stranded replicative form rna was inhibited in a dose-dependent fashion in the presence of the polyoxometalate hp ... | 1994 | 7993077 |
| murine immunoglobulin g subclass responses following immunization with live dengue virus or a recombinant dengue envelope protein. | murine immunoglobulin g (igg) subclass responses to immunization are restricted to certain subclasses depending on the nature of the immunogen. immunization with live viruses generally leads to a predominant igg2a response, which may be the most effective at resisting future challenge due to the unique effector functions of igg2a. knowledge of subclass responses following immunization with dengue vaccine candidates may be helpful in determining which candidates are most efficacious. we measured ... | 1995 | 7485699 |
| lysis of dengue virus-infected cells by natural cell-mediated cytotoxicity and antibody-dependent cell-mediated cytotoxicity. | peripheral blood mononuclear cells (pbmc) from humans without antibodies to dengue 2 virus lysed dengue 2 virus-infected raji cells to a significantly greater degree than uninfected raji cells. the addition of mouse anti-dengue antibody increased the lysis of dengue-infected raji cells by pbmc. dengue 2 immune human sera also increased lysis of dengue-infected raji cells by pbmc. these results indicate that both pbmc-mediated cytotoxicity and antibody-dependent cell-mediated cytotoxicity (adcc) ... | 1984 | 6207308 |
| the effect of interferon on flaviviruses in vitro: a preliminary study. | the preliminary results of our study in vitro on the effect of interferon on flaviviruses showed that interferon alpha and interferon beta were more effective on je viruses vip local strain and jagar strain, but less on dengue virus type 2 strain. however, the effect of these 2 interferons on the 2 strains of je viruses were still variable which need further investigations. the je virus vip local strain seemed to be more susceptible to interferon than the japanese prototype jagar strain. thus, t ... | 1984 | 6330910 |
| absence of fc receptors on aedes albopictus c6/36 cells permissive for dengue virus 2. | | 1993 | 8105669 |
| analysis of functional epitopes on the dengue 2 envelope (e) protein using monoclonal igm antibodies. | forty-two hybridomas secreting igm antibody against dengue virus were derived from spleen cells of dengue 2 infected mice. antibody from 27 of these recognised the e protein of this virus. of the 22 antibodies which neutralised dengue 2, only two cross-reacted with other flaviviruses. these 22 antibodies recognised three discrete domains on dengue virions. competitive binding studies with igg monoclonal antibodies suggested that two of the three domains were recognised by both igg and igm antibo ... | 1995 | 7541621 |
| synthesis and characterization of an infectious dengue virus type-2 rna genome (new guinea c strain). | dengue virus type 2 (den-2), a member of the flaviviridae family, has a positive-strand rna genome, 10,723 nucleotides (nt) in length and encoding a single polyprotein precursor consisting of 3391 amino acids (aa). in order to construct a full-length cdna clone, the viral genome was cloned into 5' (nt 1-2203 under the control of the t7 promoter (pt7)) and 3' (nt 2203-10,723) constructs. a full-length den-2 cdna under pt7 control was assembled in vitro after excising the two cdna inserts from the ... | 1995 | 7557426 |
| cytotoxic factors released by dengue virus-infected human blood monocytes. | human monocyte-derived cytotoxic factors (cf) induced by dengue virus were studied. using several human leukemia cell lines as precursors, the biological activities of cf in conditioned medium from dengue virus-infected monocytes were demonstrated through the measurement of tumor cell growth inhibition. the conditioned medium from dengue virus infected monocytes suppressed significantly growth of cem, hl60, k562, and u937 cells. in the presence of 10% conditioned medium (v/v) from dengue virus i ... | 1995 | 7561793 |
| a model to study cytokine profiles in primary and heterologously secondary dengue-2 virus infections. | roles of cytokines in primary and secondary dengue virus (dv) infections are not completely understood. in this study, we challenged mononuclear leukocytes (mnls) obtained from non-immune and dv-1-infected donors with dv-2 in vitro to mimic primary and heterologously secondary dv-2 infections, respectively. we found that mnls in response to dv-2 could release a large amount of interleukin-1 (il-1 beta) and tumor necrosis factor alpha (tnf alpha). however, il-1 beta and tnf alpha released by mnls ... | 1995 | 7572465 |
| dengue virus-induced human cytotoxic factor: production by peripheral blood leucocytes in vitro. | during dengue type 2 virus (dv) infection of mice a unique cytokine, the cytotoxic factor (cf), is produced which reproduces the pathological lesions seen in patients of dengue haemorrhagic fever (dhf). recently we have observed a cf-like protein in the sera of dhf cases. the present study was undertaken to investigate whether dv can stimulate human peripheral blood mononuclear cells (pbmc) in vitro to produce human cf (hcf). cultures prepared from pbmc or its enriched subpopulations were inocul ... | 1995 | 7586676 |
| phylogenetic relationships of dengue-2 viruses. | rna oligonucleotide fingerprinting studies on a large number of virus isolates previously demonstrated considerable genetic variation in isolates of dengue (den)-2 serotype. we report the entire envelope (e) glycoprotein gene and deduced amino acid sequences of 16 den-2 viruses and the phylogenetic relationships of these, plus 17 additional published den e gene sequences. comparison of den-2 e glycoprotein gene sequences revealed base substitutions scattered throughout the entire gene with as mu ... | 1993 | 8212556 |
| antibodies that block virus attachment to vero cells are a major component of the human neutralizing antibody response against dengue virus type 2. | epidemiological data strongly implicate a role for the host humoral immune response in both protection against and exacerbation of dengue virus-caused disease. in an effort to characterize elements of the normal human immune response against dengue virus we have addressed the issue of antibody-mediated neutralization of dengue virus. we show here the ability of both mouse monoclonal antibody 3h5 and human anti-dengue neutralizing sera to block binding of dengue-2 virus to monkey kidney (vero) ce ... | 1995 | 7666046 |
| identification of helper t cell epitopes of dengue virus e-protein. | the t cell proliferative response to dengue 2 (jamaica) e-glycoprotein (495 amino acids) was analyzed in vitro using either killed virus or e-protein fragments or synthetic peptides. inactivated dengue virus stimulated dengue-specific lymph node (ln) cd4+t cell proliferation in balb/c (h-2d), c3h (h-2k) and dba/1 (h-2q) but not in c57bl/6 (h-2b) mice. moreover, ln cells from dengue-virus primed balb/c mice proliferated in vitro in response to three purified non-overlapping e-protein fragments ex ... | 1993 | 7683752 |
| partial nucleotide and amino acid sequences of the envelope and the envelope/nonstructural protein-1 gene junction of four dengue-2 virus strains isolated during the 1981 cuban epidemic. | in 1981, an epidemic of dengue hemorrhagic fever (dhf) caused by dengue-2 virus occurred in cuba. this was the first dhf epidemic reported in the western hemisphere. in this study, we have analyzed four dengue-2 cuban strains for two short genomic fragments: one on the envelope (e) glycoprotein and one at the e/nonstructural protein-1 (ns1) gene junction. the e segment of these 1981 cuban isolates were more closely related to older dengue-2 virus strains such as new guinea c 1944, thailand 1964, ... | 1995 | 7694966 |
| synthesis of dengue virus rna in vitro: initiation and the involvement of proteins ns3 and ns5. | an assay for flavivirus rna-dependent rna polymerase activity in vitro was established using extracts of vero cells infected with dengue virus type 2 (den-2) or kunjin virus (kun). rna synthesis was initiated on a template of viral replicative form (rf) and rf was converted to the replicative intermediate (ri). the rna-dependent rna polymerase complex of den-2 utilised either den-2 or kun rf as template, and similarly the kun polymerase complex utilised either den-2 or kun rf template. in additi ... | 1993 | 8418788 |
| monitoring the cdna synthesis of dengue-2 virus by rt pcr. | reverse transcriptase polymerase chain reaction (rt pcr) was utilized to observe the complementary dna (cdna) synthesis from the 10723 base dengue-2 virus template by in vitro reverse transcription. the pcr product amplified from 5'-end of the genome (pcr primers n1a-e1) indicates the completeness of the cdna synthesis because the cdna primer d8b was located at 3'-end and the cdna synthesized encompassed the entire rna template. the integrity of the dengue virus rna was also determined by the cd ... | 1995 | 7730437 |
| protective efficacy in mice of a secreted form of recombinant dengue-2 virus envelope protein produced in baculovirus infected insect cells. | we constructed a recombinant baculovirus encoding a dengue (den)-2 virus envelope glycoprotein truncated of 102 amino acids (aa) at its c-terminus (d2e delta 102). the production, processing and transportation of the recombinant protein in baculovirus-infected spodoptera frugiperda (sf9) cells and its immunogenic properties in mice were compared to those of a previously characterized recombinant den-2 e-protein with a 71aa c-terminal truncation (d2e delta 71). both proteins were transported thro ... | 1994 | 7826210 |
| processing of the dengue virus type 2 proteins prm and c-prm. | a glycoprotein c-prm of 35,000 m(r) was immuno-precipitated from lysates of aedes albopictus cells infected with dengue virus type 2 (den-2) using antisera directed against the c protein or an amino-terminal fragment of the prm glycoprotein. c-prm was not detected in infected vero cells. the prm glycoprotein synthesized in infected a. albopictus and vero cells was cleaved to produce the membrane-associated virion protein (m) and the non-m fragment (pr) immediately preceding or occurring simultan ... | 1993 | 8429301 |
| dengue 2 virus ns2b and ns3 form a stable complex that can cleave ns3 within the helicase domain. | flavivirus genomic rna is translated into a large polyprotein that is processed into structural and nonstructural proteins. the n-termini of several nonstructural proteins are produced by cleavage at dibasic sites by a two-component viral proteinase consisting of ns2b and ns3. ns3 contains a trypsin-like serine proteinase domain at its n-terminus, whereas the function of ns2b in proteolysis is yet to be determined. we have used an ns3-specific antiserum, under nondenaturing conditions, to demons ... | 1993 | 8460492 |
| comparative nucleotide and deduced amino acid sequence of the envelope glycoprotein gene among three dengue virus type 2 strains isolated from patients with different disease severities in maha sarakham, northeast thailand. | the nucleotide (nt) sequence of the envelope glycoprotein (e) gene of dengue virus type 2 was determined by the primer-extension dideoxy chain-termination method for 3 dengue virus type 2 (d2) strains which had been isolated from patients with dengue fever (df), dengue hemorrhagic fever (dhf), and dengue shock syndrome (dss), in maha sarakham, northeast thailand, in 1986-1987. their nt sequences were essentially the same except for a single silent nt replacement in each dhf and dss strain compar ... | 1994 | 7855635 |
| detection of dengue-2 viral rna by reversible target capture hybridization. | a reversible target capture (rtc) sandwich hybridization technique has been developed for the detection of dengue-2 viral rna. the rtc is a form of sandwich hybridization that utilizes two probes: a poly(da)-tailed capture probe and a labeled detector probe. following hybridization of both probes to the analyte in solution, the poly(da)-tailed capture probe is used to selectively remove the hybrids by capture on oligo(dt)-coated paramagnetic beads. after elution from the beads, the presence of s ... | 1993 | 7902844 |
| nucleotide and deduced amino acid sequences of genes encoding the structural and nonstructural ns1 proteins of a dengue-2 virus isolated in china. | we have determined the nucleotide and encoded amino acid sequences of the capsid, membrane precursor, membrane, envelope, and nonstructural ns1 protein genes of a dengue-2 virus (d2-04) isolated from a patient in hainan, china. the sequenced region contains a gene organization similar to that of other flaviviruses. the overall amino acid sequence similarity between d2-04 and other dengue-2 viruses is greater than 92%, whereas that between d2-04 and members of the other dengue serotypes is about ... | 1994 | 7911607 |
| dengue virus-specific memory t cell responses in human volunteers receiving a live attenuated dengue virus type 2 candidate vaccine. | a live attenuated dengue virus type 2 candidate vaccine (16681-pdk53) was evaluated in a phase i trial in 10 nonimmune adult volunteers. the dengue virus-specific memory t cell responses were analyzed as part of this study. dengue virus-specific t cell proliferative responses were observed in all subjects after stimulating their peripheral blood mononuclear cells with live viruses or noninfectious viral antigens. the highest proliferative response was against dengue virus type 2, although cross- ... | 1994 | 7912253 |
| evaluation of enemas for exposing aedes aegypti to suspensions of dengue-2 virus. | to determine if enemas could be used to simulate oral exposure of aedes aegypti to dengue-2 virus, we compared infection rates of mosquitoes administered an enema of a blood suspension containing dengue-2 virus to infection rates in mosquitoes that imbibed the same suspension from a drop of blood. in 1 of 4 experiments infection rates were significantly different. more importantly, during 2 of the 4 trials, 100% of the mosquitoes in the enema treatment group were infected. we speculate that the ... | 1995 | 8551311 |
| failure of immune sera to neutralize dengue-2 virus in intrathoracically inoculated aedes aegypti. | aedes aegypti became infected when inoculated with a mixture of dengue-2 virus and anti-dengue-2 antibodies, but not when they were exposed to the same mixture per os. this phenomenon merits more detailed investigation. understanding why this difference in mosquito infection rate occurs may lead to improved dengue virus assays or provide insights into the nature of dengue virus-antibody interactions. | 1995 | 8551312 |
| synaptophysin and neurofilament expression in neurons infected with dengue virus. | the expression of two genes encoding the neuronal specific proteins synaptophysin and high molecular weight neurofilaments was investigated in primary cell cultures of embryonic mouse brain infected with dengue virus type 2, using immunocytochemistry and western blot analysis with monoclonal antibodies. the viral infection leads to a 20-fold induction in the expression of the mentioned synaptogenesis-related proteins. these results suggest a correlation between virus infection and neuropathology ... | 1994 | 7919816 |
| genetically engineered resistance to dengue-2 virus transmission in mosquitoes. | the control of arthropod-borne virus diseases such as dengue may ultimately require the genetic manipulation of mosquito vectors to disrupt virus transmission to human populations. to reduce the ability of mosquitoes to transmit dengue viruses, a recombinant sindbis virus was used to transduce female aedes aegypti with a 567-base antisense rna targeted to the premembrane coding region of dengue type 2 (den-2) virus. the transduced mosquitoes were unable to support replication of den-2 virus in t ... | 1996 | 8629025 |
| pathogen-derived resistance to dengue type 2 virus in mosquito cells by expression of the premembrane coding region of the viral genome. | the full-length premembrane (prm) coding region of the dengue virus type 2 (den-2; jamaica) genome was expressed in c6/36 (aedes albopictus) cells in either the sense or the antisense orientation from a double subgenomic sindbis (dssin) virus. northern (rna) blot analysis confirmed the expression of sense or antisense den-2 prm rna in infected c6/36 cells. prm protein was demonstrated in cells infected with dssin virus expressing den-2 sense rnas by an immunofluorescence assay. c6/36 cells were ... | 1996 | 8642634 |
| phenotypic characteristics of dengue 2 virus persistently infected in a c6/36 clone of aedes albopictus cells. | a c6/36 cell culture persistently infected by dengue 2 virus was established and retained for over 20 weeks. no cpe was observed at any stage of infection. however, some giant cells up to 2- or 3-fold the diameter of normal cells appeared in the established culture. extracellular virus titers fluctuated with a periodic tendency while the antigen level remained constant, suggesting some viral particles evolved into noninfectious defective interfering particles. plaque size tended to change during ... | 1994 | 7928286 |