host

(noun)

A cell or organism which harbors another organism or biological entity, usually a parasite.

Related Terms

Examples of host in the following topics:

  • Extent of Host Involvement

    • Host-pathogen interactions are the interactions taking place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
    • Host-pathogen interactions are the interactions that take place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
    • By definition, all pathogens damage their host to some extent.
    • The appearance and severity of disease resulting from the presence of any pathogen depends upon the ability of that pathogen to damage the host as well as the ability of the host to resist the pathogen.
    • Primary pathogens may also cause more severe disease in a host with depressed resistance than would normally occur in an immunosufficient host.

  • Host Range

    • A virus' host range is the range of cell types and host species a virus is able to infect.
    • Non-specific host defenses function early in an encounter with a virus to prevent or limit infection, while the specific host defenses function after infection in recovery to provide immunity for subsequent challenges.
    • The host has many barriers against infection that are inherent in the organism.
    • If a host lacks the receptor for a virus, or if the host cell lacks some component necessary for the replication of a virus, the host will inherently be resistant to that virus.
    • structure of ICAM-1 molecule that enables viruses to bind to host's cell membrane.

  • Providing Hosting/Bandwidth

    • The inexorable rise of zero-cost canned hosting sites (see the section called "Canned Hosting" in Technical Infrastructure) for open source projects has meant that it is increasingly unnecessary for projects to get corporate support for basic project-hosting infrastructure.
    • The most common technique for creating this association is for the company to host the project's resources under the company's domain name, thus getting association through the project's URLs.
    • After all, there are a lot of free places to host these days.
    • The community may eventually feel that the implied misallocation of credit is not worth the minor convenience brought by donated hosting, and may even attempt to take the project elsewhere.
    • So if you want to provide hosting, do so—but if you are actually trying to create a public association between your company and the project, make sure that the level of support you provide is matched to the amount of credit you claim, whether you claim it via URL, banner ads, or some other means.

  • Direct Damage

    • Direct damage to the host is a general mechanism utilized by pathogenic organisms to ensure infection and destruction of the host cell.
    • Direct damage to the host is a general mechanism utilized by pathogenic organisms to ensure infection and destruction of the host cell.
    • The promotion of disease is characterized by the ability of a pathogenic organism to enter a host and inflict damage and destruction onto the host cell.
    • Often times, bacteria will directly attach themselves to host cells and utilize nutrients from the host cell for their own cellular processes.
    • Upon the use of host nutrients for its own cellular processes, the bacteria may also produce toxins or enzymes that will infiltrate and destroy the host cell.

  • Ecology, Epidemiology, and Evolution of Pathogens

    • Pathogens have evolved to adapt to their environment and their host in order to survive.
    • Diseases transferred from nonhuman to human hosts are known as zoonoses.
    • Under disease invasion, when a parasite invades a new host species, it may become pathogenic in the new host.
    • One definition of this is the host's parasite-induced loss of fitness.
    • This might induce faster host death, and act against the parasite's fitness by reducing probability to encounter another host (killing the host too fast to allow for transmission).

  • Canned Hosting Sites

    • These are all the credible, well-established canned hosting sites that I know about as of early 2013.
    • As noted in the section called "Canned Hosting", each site imposes its own particular restrictions in exchange for the convenience of hosting your open source project's collaboration infrastructure: each one supports only particular version control systems, bug trackers, etc.
    • Again, en.wikipedia.org/wiki/Comparison_of_open_source_software_hosting_facilities has a good comparison of canned hosting sites.
    • Instead, this appendix describes the canned hosting sites that I see being used most often by open source projects.

  • Extracellular Immune Avoidance

    • A pathogen's success depends on its ability to evade the host's immune responses.
    • A pathogen's success depends on its ability to evade the host's immune responses.
    • These proteins often shutdown the defenses of the host.
    • A lot of pathogens release compounds that misdirect or diminish the host's immune response.
    • Another common strategy that is used is to mask antigens with host molecules in order to evade detection by the immune system.

  • Regulating Virulence

    • Host-mediated pathogenesis is often important because the host can respond aggressively to infection with the result that host defense mechanisms do damage to host tissues while the infection is being countered.
    • Therefore, it was believed that less virulent pathogens that allowed the host to move around and interact with other hosts should have greater success reproducing and dispersing.
    • Pathogen strains that kill the host can increase in frequency as long as the pathogen can transmit itself to a new host, whether before or after the host dies.
    • If the pathogen's virulence kills the host and interferes with its own transmission to a new host, virulence will be selected against.
    • We can say that the neurotoxin is not directed at the human host.

  • Batch Culture of Bacteriophages

    • Bacteriophage cultures require host cells in which the virus or phage multiply.
    • Virus or phage cultures require host cells in which to multiply.
    • Host growth conditions also influence the ability of the phage to attach and invade them.
    • An altogether different phage type, the filamentous phages, make the host cell continually secrete new virus particles.
    • Virus or phage cultures require host cells in which to multiply.

  • Hosts for Cloning Vectors

    • The majority of molecular cloning experiments begin with a laboratory strain of the bacterium E. coli (Escherichia coli) as the host.
    • A very large number of host organisms and molecular cloning vectors are in use, but the great majority of molecular cloning experiments begin with a laboratory strain of the bacterium E. coli (Escherichia coli) and a plasmid cloning vector.
    • Specialized applications may call for specialized host-vector systems.
    • For example, if the experimentalists wish to harvest a particular protein from the recombinant organism, then an expression vector is chosen that contains appropriate signals for transcription and translation in the desired host organism.
    • Alternatively, if replication of the DNA in different species is desired (for example transfer of DNA from bacteria to plants), then a multiple host range vector (also termed shuttle vector) may be selected.