Tissue tropism

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Tissue tropism is the range of cells and tissues of a host that support growth of a particular pathogen, such as a virus, bacterium or parasite. [1] [2]


Some bacteria and viruses have a broad tissue tropism and can infect many types of cells and tissues. [1] Other viruses may infect primarily a single tissue. [1] For example, rabies virus affects primarily neuronal tissue.

Influencing factors

Factors influencing viral tissue tropism include:

The cellular receptors are the proteins found on a cell or viral surface. These receptors are like keys, allowing the viral cell to fuse with or attach itself to a cell. The way that these proteins are acquired is through a similar process to that of an infection cycle.

How 'tropic' tissue is acquired

HIV HIV gross cycle only.png

Tissue tropism develops in the following stages:

Example: HIV has a gp120, which is precisely what the CD4 marker is on the surface of the macrophages and T cells. Thus HIV can enter T cells and macrophages

See also

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  1. 1 2 3 McCall, LI; Siqueira-Neto, JL; McKerrow, JH (May 2016). "Location, Location, Location: Five Facts about Tissue Tropism and Pathogenesis". PLOS Pathogens. 12 (5): e1005519. doi: 10.1371/journal.ppat.1005519 . PMC   4881934 .
  2. Silva Pereira, Sara; Trindade, Sandra; De Niz, Mariana; Figueiredo, Luisa M. (31 May 2019). "Tissue tropism in parasitic diseases". Open Biology. 9 (5): 190036. doi:10.1098/rsob.190036. ISSN   2046-2441. PMC   6544988 . PMID   31088251.