共查询到20条相似文献，搜索用时 31 毫秒
1.
Human rotavirus type 2: cultivation in vitro 总被引：54，自引：0，他引：54
R G Wyatt W D James E H Bohl K W Theil L J Saif A R Kalica H B Greenberg A Z Kapikian R M Chanock 《Science (New York, N.Y.)》1980,207(4427):189-191
A strain of type 2 human rotavirus (Wa) was grown to relatively high titer through 14 passages in primary cultures of African green monkey kidney (AGMK) cells. This passage series was initiated with virus that had been passaged 11 times serially in newborn gnotobiotic piglets. In contrast, virus present in the stool of patient Wa as well as virus from the first, second, or third passage in piglets could not be propagated successfully in African green monkey kidney cells. Prior to each passage in cell culture, the virus was treated with trypsin and the inoculated cultures were centrifuged at low speed. Cultivation of a type 2 human rotavirus should aid attempts to characterize this virus and to develop a means of immunoprophylaxis for a serious diarrheal disease of human infants. 相似文献
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Leukemogenic activity of ether-extracted Rauscher leukemia virus 总被引：3，自引：0，他引：3
G P Shibley F E Durr G Schidlovsky B S Wright R Schmitter 《Science (New York, N.Y.)》1967,156(3782):1610-1613
After rapid multiple extractions of mouse plasma virus with ether, the aqueous solution contained viral nucleoids that were infectious when inoculated intracranially into newborn BALB/c mice. The infectivity associated with the ether extract was not neutralized by the specific antibody prepared against the whole virus. No intact virus has been seen in these preparations. Treatment with ether completely removed the virus envelope from the particle and produced an apparently homogeneous preparation of viral nucleoids. After the extractions with ether, leukemogenic activity was inactivated by exposure to ribonuclease. The leukemogenic activity of the many-passaged Rauscher virus that has been propagated in tissue culture and that has low infectivity was also retained, and, in two experiments in which material was inoculated intracranially into mice, this activity appeared to have been enhanced by multiple extractions with ether. 相似文献
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通过Y8504“兔瘟”病毒株在乳鼠连续断代,建立了一株能适应于乳鼠中生长的病毒。此病毒株能规律地致死接种的乳鼠。用乳鼠适应毒株,在乳鼠成功地进行了“兔瘟”病毒对物理和化学因素作用抵抗力的检测以及血清中和试验。本研究中所得结果与成年兔中试验的结果几乎一致。因此,可能用乳鼠适应毒株和乳鼠代替兔适应毒株和成年兔子“兔瘟”病毒特性的研究。 相似文献
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Pathogenesis of dengue: challenges to molecular biology 总被引：89，自引：0，他引：89
S B Halstead 《Science (New York, N.Y.)》1988,239(4839):476-481
Dengue viruses occur as four antigenically related but distinct serotypes transmitted to humans by Aedes aegypti mosquitoes. These viruses generally cause a benign syndrome, dengue fever, in the American and African tropics, and a severe syndrome, dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), in Southeast Asian children. This severe syndrome, which recently has also been identified in children infected with the virus in Puerto Rico, is characterized by increased vascular permeability and abnormal hemostasis. It occurs in infants less than 1 year of age born to dengue-immune mothers and in children 1 year and older who are immune to one serotype of dengue virus and are experiencing infection with a second serotype. Dengue viruses replicate in cells of mononuclear phagocyte lineage, and subneutralizing concentrations of dengue antibody enhance dengue virus infection in these cells. This antibody-dependent enhancement of infection regulates dengue disease in human beings, although disease severity may also be controlled genetically, possibly by permitting and restricting the growth of virus in monocytes. Monoclonal antibodies show heterogeneous distribution of antigenic epitopes on dengue viruses. These epitopes serve to regulate disease: when antibodies to shared antigens partially neutralize heterotypic virus, infection and disease are dampened; enhancing antibodies alone result in heightened disease response. Further knowledge of the structure of dengue genomes should permit rapid advances in understanding the pathogenetic mechanisms of dengue. 相似文献
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Paprotka T Delviks-Frankenberry KA Cingöz O Martinez A Kung HJ Tepper CG Hu WS Fivash MJ Coffin JM Pathak VK 《Science (New York, N.Y.)》2011,333(6038):97-101
The retrovirus XMRV (xenotropic murine leukemia virus-related virus) has been detected in human prostate tumors and in blood samples from patients with chronic fatigue syndrome, but these findings have not been replicated. We hypothesized that an understanding of when and how XMRV first arose might help explain the discrepant results. We studied human prostate cancer cell lines CWR22Rv1 and CWR-R1, which produce XMRV virtually identical to the viruses recently found in patient samples, as well as their progenitor human prostate tumor xenograft (CWR22) that had been passaged in mice. We detected XMRV infection in the two cell lines and in the later passage xenografts, but not in the early passages. In particular, we found that the host mice contained two proviruses, PreXMRV-1 and PreXMRV-2, which share 99.92% identity with XMRV over >3.2-kilobase stretches of their genomes. We conclude that XMRV was not present in the original CWR22 tumor but was generated by recombination of two proviruses during tumor passaging in mice. The probability that an identical recombinant was generated independently is negligible (~10(-12)); our results suggest that the association of XMRV with human disease is due to contamination of human samples with virus originating from this recombination event. 相似文献
6.
H F Clark 《Science (New York, N.Y.)》1978,199(4333):1072-1075
Several strains of attenuated rabies virus lacking the capacity to kill adult mice acquired a high lethal potential for mice after one to five serial passages in murine or human neuroblastoma cells. The virulence acquired after passage in neuroblastoma cells is a stable genetic trait retained during subsequent passage of viruses in nonneuroblastoma cell systems. 相似文献
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Chikungunya virus and dengue type 2 virus were isolated from a single blood specimen taken from a patient in the acute phase of a dengue-like illness seen at Christian Medical College Hospital, Vellore, South India, in October 1964. In serial blood specimens collected from this patient there was an increase in antibody to these same two viruses. The technique for unmasking an agent (such as dengue) with a long incubation period in mice in the presence of an agent with a short incubation period is described. 相似文献
8.
Endocarditis in mice infected with Coxsackie virus B4 总被引：1，自引：0，他引：1
G E Burch N P DePasquale S C Sun W J Mogabgab A R Hale 《Science (New York, N.Y.)》1966,151(709):447-448
Endocarditis has not been generally considered to be a complication of viral infection. We show that mural and valvular endocarditis can be produced in mice infected with Coxsackie virus B(4). Because this virus commonly infects man and is highly cardiotropic, it is important to know whether it produces valvular lesions in man similar to those we describe in mice. 相似文献
9.
Korean hemorrhagic fever: propagation of the etiologic agent in a cell line of human origin 总被引：4，自引：0，他引：4
G R French R S Foulke O A Brand G A Eddy H W Lee P W Lee 《Science (New York, N.Y.)》1981,211(4486):1046-1048
The etiologic agent of Korean hemorrhagic fever has been propagated in a human cultured cell line derived from a carcinoma of the lung. The cells, described as type II, alveolar epithelial, support replication of the agent and successive passages. Antigen of the Korean hemorrhagic fever agent is readily detected in infected cells by means of direct or indirect fluorescent antibody techniques. Previous attempts to propagate this agent in vitro had been unsuccessful. 相似文献
10.
为进一步了解鹅细小病毒（GPV）在番鸭成纤维细胞（MDEF）上的适应性及病毒增殖情况,将GPV在MDEF上连续传12代培养,通过PCR、免疫荧光、流式细胞等方法分析其生物学特性。PCR检测结果显示,扩增到大小为734bp的非结构蛋白基因片段,将10倍梯度稀释的病毒悬液接种细胞培养65h后,10-6倍接种的细胞仍能检测到病毒核酸。免疫荧光检测显示,兔抗GPV阳性血清能对染毒的病灶产生特异性荧光染色。流式细胞试验结果进一步证实,GPV在MDEF上增殖速度比较慢,病毒的感染会造成MDEF的早期凋亡。说明该GPV株感染MDEF后虽未产生细胞病变,但病毒能在MDEF中增殖,为GPV开展细胞依赖性相关研究奠定基础。 相似文献
11.
A characteristic cytopathic effect was obtained with canine distemper virus (Onderstepoort strain) propagated in chick embryo fibroblast monolayer tissue culture. In limiting dilutions the lesions were focal. The titer at the 20th tissue culture passage was approximately 10(5) TCD(50)/ml. Cytopathogenicity was specifically inhibited by distemper immune serum. Minute plaques were produced under agar overlay. 相似文献
12.
In this paper,the character of viral clones from early and late passages after serial passages of Trichoplusia ni single nuclear polyhedrosis virus in a Tn 5B1-4 cell line is described.It demonstrated that no significant difference was observed in the infectivity of the cell culture supernatants of various passages to the cell line.The number of polyhedra produced in a cell and infectivity of polyhedra to T.ni larvae declined strikingly with the increase of passages.The polyhedra without virions began to increase from passage to passage.The result of restriction enzyme digestion showed that the DNA restriction fragments of the clones were different from wild virus DNA,although they came from a homogeneous viral DNA.The mutation of viral DNA resulted in the in crease of noninfectious polyhedra without virions and in the increase of the number of polyhedra produced in cell line as well as virulence of the polyhydrosis inclusion bodys to T.ni larvae after prolonged passages of Tn SNPV in the cell culture. 相似文献
13.
An epithelial-like cell has been developed in line culture that apparently is stable. Although initially isolated cells were incapable of supporting the growth of poliovirus, the cells of the sixth and later passages allowed virus to propagate. The early, nonsusceptible cells were fibroblastic in appearance, in contrast to the epithelial type, poliovirussusceptible, derived cell of later passages. 相似文献
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ZHANG De-Li LI Liu-jin XIA Geng-tian HE Xu-yu GAO Bu-xian BAI Xiao-hong HUANG Gao-sheng LIU Shang-gao YEN Lung-fei FANG Fu-de 《中国农业科学(英文版)》2002,1(9):1054-1066
Under the prerequisite that the incidence of cancer or tumor in negative-control nude mice inoculated subcutaneously with primary feline or canine kidney cell cultures purified in vitro at passage 3 was 0(0/22) and 0 (0/10), respectively. The incidence of the progressively-growing malignant tumor(MT) in positive-control nude mice inoculated subcutaneously with Hela cell cultures of KB, X, or NM20/X strain was 10/10, 25/25 and 5/51, respectively. The results showed that the incidence of tumor in nude mice with di-and hyperploid YB strain of MDCK cell during 17 - 23 passages, with hyper- and hypoploid KA strain of MDCK cell during 6 - 8 passages, with hypoploid WB strain of MDCK cell on passage 6, with hyper-and hypopioid H strain of MDCK cell during 8 - 24 passages was 2/24, 6/10, 5/10 and 10/15, respectively. The chromosomal analysis results showed that the ratio of difference in the rate of modal chromosome number between high(mcs + n) and lowest (mcs)passages was not more than 5- 15% and the structure aberrations was generally 0-3%. These results proved that the genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species-specific. MDCK line has tumorigenicity no matter what its chromosome karyotype is, at least it has very low tumorigenicity even when its modal chromosome number is hypoploid. It is thus evident that MDCK cell of WB or H strain can be approved as substrate for the preparation of attenuated viral vaccines, but MDCK cell of YB or KA strain can not be approved as substrate for the preparation of attenuated viral vaccines. 相似文献
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Hwang WS Ryu YJ Park JH Park ES Lee EG Koo JM Jeon HY Lee BC Kang SK Kim SJ Ahn C Hwang JH Park KY Cibelli JB Moon SY 《Science (New York, N.Y.)》2004,303(5664):1669-1674
Somatic cell nuclear transfer (SCNT) technology has recently been used to generate animals with a common genetic composition. In this study, we report the derivation of a pluripotent embryonic stem (ES) cell line (SCNT-hES-1) from a cloned human blastocyst. The SCNT-hES-1 cells displayed typical ES cell morphology and cell surface markers and were capable of differentiating into embryoid bodies in vitro and of forming teratomas in vivo containing cell derivatives from all three embryonic germ layers in severe combined immunodeficient mice. After continuous proliferation for more than 70 passages, SCNT-hES-1 cells maintained normal karyotypes and were genetically identical to the somatic nuclear donor cells. Although we cannot completely exclude the possibility that the cells had a parthenogenetic origin, imprinting analyses support a SCNT origin of the derived human ES cells. 相似文献
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猪瘟病毒C株全长cDNA感染性克隆的构建及病毒拯救 总被引：3，自引：1，他引：2
【目的】建立猪瘟病毒研究技术平台,为进一步研究猪瘟病毒C株在细胞中的增殖机制及猪瘟病毒标记疫苗奠定基础。【方法】本试验以猪瘟病毒C株为研究材料,经RT-PCR扩增获得涵盖全长的6个片段,用合适的酶切位点连接,成功构建了C株全长感染性克隆pAC-CS。体外转录得到RNA,然后将其分别转染BHK-21和SK6细胞。拯救的病毒通过上清传代(常规病毒传代)和带毒细胞传毒繁殖。【结果】通过RT-PCR、免疫过氧化酶单层细胞试验和兔体发热试验检测,表明病毒拯救成功。经比较以电转的方式转染SK6的效果较好。通过带毒细胞传代,至12代时病毒滴度稳定达104TCID50?mL-1,而上清传代至第3代时用免疫过氧化酶单层细胞试验(IPMA)不能检测出病毒。【结论】成功构建了猪瘟病毒C株感染性克隆;拯救C株时以SK6细胞电转较好;带毒细胞传代培养C株有利于获得较高滴度的病毒。 相似文献
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A new mammalian cell strain was established from guinea pig spleen tissues and has shown interesting virus sensitivity. Several viruses have been successfully propagated in the cells. For one of these, poliovirus, it represents one of the two successful attempts at propagating the virus in nonprimate or nonhuman cultures. 相似文献