• proteins
  • Researchers at Johns Hopkins and George Washington universities report new evidence that proteins created by defective forms of HIV long previously believed to be harmless actually interact with our immune systems and are actively monitored by a specific type of immune cell, called cytotoxic T cells. (eurekalert.org)
  • After verifying that defective HIV proviruses created HIV proteins, the researchers then tested whether human immune system cells could biologically recognize and interact with those proteins. (eurekalert.org)
  • The cytotoxic T lymphocytes' ability to identify and target the real threat appears to be greatly impaired, because they may attack proteins from defective proviruses instead of the real thing," says Ho. (eurekalert.org)
  • The defective ribosomal product (DRiP) hypothesis of endogenous Ag processing posits that rapidly degraded forms of nascent proteins are a major source of peptide ligands for MHC class I molecules. (jimmunol.org)
  • This rapidity of presentation, coupled with the relatively long half-life ( t 1/2 ) of most viral proteins, engendered the defective ribosomal product (DRiP) hypothesis of Ag presentation: a subset of newly synthesized proteins are defective in some manner and rapidly degraded intracellularly, yielding peptides for MHC class I Ag presentation to enable rapid immunosurveillance of viral and cellular translation products ( 2 ). (jimmunol.org)
  • Every cell that is successfully transfected with all three DNA fragments will produce the necessary proteins to produce infective viruses. (wikipedia.org)
  • Biochemically, many viruses inhibit the synthesis of host DNA, RNA, proteins directly or even interfere with protein-protein, DNA-protein, RNA-protein interactions at the subcellular level. (wikipedia.org)
  • Virol
  • doi:10.1038/294273a0, alternatively at ResearchGate H. M. Fidanián, W. N. Drohán, M. A. Baluda: RNA of simian sarcoma-associated virus type 1 produced in human tumor cells, in: J Virol. (wikipedia.org)
  • pathogen
  • Since Dmitri Ivanovsky 's 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, about 5,000 virus species have been described in detail, although there are millions of types. (wikipedia.org)
  • The human pathogen hepatitis D virus is a "defective" RNA virus similar to a viroid. (wikipedia.org)
  • latent
  • Viruses are also responsible for the common cold, childhood exanthems (such as chickenpox, measles, rubella), latent infections (such as herpes simplex), some cancers or lymphomas (such as Epstein-Barr virus), and diseases of all organ systems. (thefreedictionary.com)
  • There are three types of persistent infections, latent, chronic and slow, in which the virus stays inside the host cell for prolonged periods of time. (wikipedia.org)
  • simian
  • Woolly monkey sarcoma virus (WMSV), with synonym Simian sarcoma virus (often abbreviated by SSV, but this may also stand for some species called 'Sulfolobus spindle-shaped virus', that belong to different genera in family Fuselloviridae) is a species of gammaretrovirus that infects primates. (wikipedia.org)
  • For its reproduction the virus needs a helper or associated virus which is called Simian sarcoma associated virus (SSAV). (wikipedia.org)
  • Ruian Ke
  • We have shown that the defective virus not only transmits with the virus but increases the transmission of the functional virus," says Ruian Ke, a UCLA postdoctoral scholar in the department of ecology and evolutionary biology and the lead author of the study. (infectioncontroltoday.com)
  • We've shown that the defective virus not only goes with the normal virus, but increases the transmission of that virus," says scientist Ruian Ke, also of UCLA. (nsf.gov)
  • genetic
  • Aaskov and Holmes collected genetic sequences from from 15 people in Myanmar sampled over an 18-month period, all of whom were infected with the DENV-1 virus and nine of whom were also infected with the defective version. (infectioncontroltoday.com)
  • The scientists analyzed the genetic sequences of both the defective and normal dengue viruses to estimate how long the defective virus had been transmitting in the human population. (infectioncontroltoday.com)
  • Aaskov and Holmes collected genetic sequences from the defective viruses from 15 people sampled over an 18-month period in Myanmar. (nsf.gov)
  • Viruses are considered by some to be a life form, because they carry genetic material, reproduce, and evolve through natural selection, but lack key characteristics (such as cell structure) that are generally considered necessary to count as life. (wikipedia.org)
  • Antigens
  • Lastly, biologic effects include the viruses' ability to affect the activity of antigens and immunologlobulins in the host cell. (wikipedia.org)
  • DIPs
  • The existence of DIPs has been known about for decades, and they can occur within nearly every class of both DNA and RNA viruses. (wikipedia.org)
  • DIPs have been shown to play a role in pathogenesis of certain viruses. (wikipedia.org)
  • UCLA
  • Defective viruses, thought for decades to be essentially garbage unrelated to the transmission of normal viruses, now appear able to play an important role in the spread of disease, new research by UCLA life scientists indicates. (infectioncontroltoday.com)
  • In findings published Feb. 28 in the journal PLoS Pathogens, UCLA scientists and their colleagues report for the first time a significant link between a defective virus and an increased rate of transmission of a major disease. (infectioncontroltoday.com)
  • The idea has always been that defective viruses are either meaningless or detrimental," says James O. Lloyd-Smith, a UCLA assistant professor of ecology and evolutionary biology and the senior author of the research. (infectioncontroltoday.com)
  • The idea has always been that defective viruses are either meaningless or detrimental," says James Lloyd-Smith, an ecologist and evolutionary biologist at the University of California, Los Angeles (UCLA). (nsf.gov)
  • herpes
  • Following the completion of his graduate studies, he trained as post-doctoral fellow on molecular genetics of herpes simplex virus (HSV) at the University of Chicago with Dr. Bernard Roizman. (wikipedia.org)
  • cells
  • New viruses are then released either by destroying their host cell or by forming small buds that break off and infect other cells. (thefreedictionary.com)
  • In the study, the scientists collected nine different defective HIV proviruses from six people infected with HIV, then transfected cultures of human immune cells with them in the laboratory. (eurekalert.org)
  • The group again transfected cells in the lab with 6 different types of defective HIV provirus taken from patients. (eurekalert.org)
  • The origins of viruses in the evolutionary history of life are unclear: some may have evolved from plasmids -pieces of DNA that can move between cells-while others may have evolved from bacteria. (wikipedia.org)
  • This product is not required until after the viral assembly process, which means that the disabled virus can undergo a single round of replication in normal human cells, but the progeny virus cannot infect new cells. (wikipedia.org)
  • The Abelson murine leukemia virus (Ab-MLV or A-MuLV) is a retrovirus (Class VI) used to induce transformation of murine lymphoid cells. (wikipedia.org)
  • Natural transformations can include viral cancers, such as human papillomavirus (HPV) and T-cell Leukemia virus type I. Hepatitis B and C are also the result of natural viral transformation of the host cells. (wikipedia.org)
  • A DIP can usually still penetrate host cells, but requires another fully functional virus particle (the 'helper' virus) to co-infect a cell with it, in order to provide the lost factors. (wikipedia.org)
  • infects
  • The dengue virus infects between 50 million and 100 million people each year in Southeast Asia, South America, parts of the United States and elsewhere. (infectioncontroltoday.com)
  • Dengue virus infects some 50-100 million people annually in Southeast Asia, South America and parts of the United States. (nsf.gov)
  • 2001
  • In a paper published this week in the journal PLoS Pathogens, scientists funded by the National Science Foundation (NSF) report a significant link between one such defective virus and the high rate of transmission of DENV-1 in Myanmar in 2001. (nsf.gov)
  • 1892
  • In 1892, the Russian biologist Dmitri Ivanovsky used this filter to study what is now known as the tobacco mosaic virus. (wikipedia.org)
  • Discovery of the viroid triggered the third major extension of the biosphere in history to include smaller lifelike entities--after the discovery of the "subvisible" microorganisms by Antonie van Leeuwenhoek in 1675 and the "submicroscopic" viruses by Dmitri Iosifovich Ivanovsky in 1892. (wikipedia.org)
  • Parvoviridae
  • Within the family parvoviridae, the dependovirus genus was given a distinct classification due to their dependence on another virus. (wikipedia.org)
  • immune response
  • In this particular case, the KAN-1-induced defective RNA-encoded protein PB2∆ enhances the overwhelming immune response characteristic for highly pathogenic H5N1 viruses, leading to a more severe phenotype in vivo. (sigmaaldrich.com)
  • Viral infections in animals provoke an immune response that usually eliminates the infecting virus. (wikipedia.org)
  • The virus causes a very mild immune response, lending further support to its apparent lack of pathogenicity. (wikipedia.org)
  • Brain
  • Major has been quoted extensively in news coverage of the finding that natalizumab (Tysabri) and related monoclonal antibody-based therapies increase the risk of a rare brain disease caused by JC virus. (wikipedia.org)
  • vesicular
  • his thesis research focused on vesicular stomatitis virus (VSV) under the supervision of Dr. David Baltimore and Dr. Harvey Lodish. (wikipedia.org)
  • species
  • Bunyaviridae , host plant species, virus concentration in inoculum. (apsnet.org)
  • Most virus species have virions that are too small to be seen with an optical microscope . (wikipedia.org)
  • This can be narrow, meaning a virus is capable of infecting few species, or broad, meaning it is capable of infecting many. (wikipedia.org)
  • known
  • More than 400 types of viruses that cause a great variety of illness are known. (thefreedictionary.com)
  • They are only limited by the virus they must infect with, also known as the helper virus. (wikipedia.org)
  • For example: The 4-substituted Neu5Ac2en derivatives (Figure 3), 4-amino-Neu5Ac2en (Compound 1), which showed two orders of magnitude better inhibition of influenza virus sialidase than Neu5Ac2en5 and 4-guanidino-Neu5Ac2en (Compound 2), known as Zanamivir, which is now marketed for treatment of influenza virus as a drug, have been designed by von Itzstein and coworkers. (wikipedia.org)