Perfect use of imperfection
Article Abstract:
An investigation has shown how cells make proteins and how waste products are used to provide advance warning about proteins currently in production.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
User Contributions:
Comment about this article or add new information about this topic:
In vivo priming of virus-specific cytotoxic T lymphocytes with synthetic lipopeptide vaccine
Article Abstract:
Immunity to an organism that causes disease is a complex phenomenon involving many types of cells of the immune system. Cytotoxic T cells, a subset of lymphocytes, can recognize a cell containing a foreign molecule and destroy the cell. The T cells recognize a portion of the foreign molecule along with host molecules known as major histocompatibility antigens. Since T cells recognize only a portion of the foreign molecule, it was hoped that peptides that are identical to that segment and are synthesized in the laboratory could be used to stimulate the immune system to respond. Although this artificial stimulation works in helper T cells, which are T cells involved in the production of antibodies, synthetic peptides do not stimulate cytotoxic, or killer, T cells. A peptide present in a structural protein of a virus that causes influenza was shown to stimulate and activate cytotoxic T cells when it was attached to a lipoprotein, a molecule consisting of fatty acids and protein. The mechanism of activation may involve the ability of the peptide to enter the cytoplasm of the cell, or to associate with certain major histocompatibility antigens, of which there are many, or for the complex to be inserted into the cell membrane. Peptides are being developed for vaccines. However, many different peptides from the immunogenic proteins of infectious organisms may have to be used in any given vaccine to ensure that the peptides will combine with certain host major histocompatibility antigens and will activate the immune response of cytotoxic T cells.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1989
User Contributions:
Comment about this article or add new information about this topic:
A role for the proteasome regulator PA28-alpha in antigen presentation
Article Abstract:
Enhanced expression of PA28-alpha, 20S proteasome's interferon-gamma-inducible activator, increases the presentation of influenza nucleoprotein and the recognition by pp89-specific cytotoxic cells. A human or murine gene encoding the PA89-alpha subunit transfected a mouse fibroblast line expressing murine cytomegalovirus pp89 virus. Results show that PA28-alpha influence antigen presentation by altering the 20S proteasome's cleavage properties. The PA28-alpha dependent increase in antigen presentation is restricted to the MCMV pp89 antigen.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1996
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Autumn foraging dynamics of woodland caribou in experimentally manipulated habitats, northeastern Washington, USA
- Abstracts: Imprinting and the origin of parasite-host species associations in brood-parasitic indigobirds, Vidua chalybeata
- Abstracts: Evidence of atmospheric sulphur in the martian regolith from sulphur isotopes in meteorites. Anomalous 17O compositions in massive sulphate deposits on the Earth
- Abstracts: Females prefer noninfected males as mates in the grain beetle Tenebrio molitor: Evidence in pre- and postcopulatory behaviours
- Abstracts: Female song sparrow, Melospiza melodia, response to simulated conspecific and heterospecific intrusion across three seasons