User:Rachelbaer/Intracellular parasite

Types of parasites
There are two main types of intracellular parasites: Facultative and Obligate. 

Facultative intracellular parasites are capable of living and reproducing in or outside of host cells. Obligate intracellular parasites, on the other hand, need a host cell to live and reproduce. Many of these types of cells require specialized host types, and invasion of host cells occurs in different ways. [I added citations]

Exceptions
Polypodium is a metazoan intracellular parasite, distinct from most if not all other intracellular parasites for this reason. Specifically Polypodium Hydriforme invades oocytes of paddlefish and sturgeon and develops into a stolon before leaving once spawned.

Invasion
Most intracellular parasites are only able to infect specific types of cells, and because of this their methods for invasion will differ. Some will work with specific components in or on the host cell, an example being Trypanosoma cruzi. and Leishmania amazonensis. These parasites will attach themselves to the host cell while increasing the intracellular calcium, which in turn disrupts the actin at the site of attachment, causing the host cell to create a lysosomal-barrier around the disruption. The parasite will take advantage of this membrane and produce a vacuole in the host cell. Other intracellular parasites have developed different ways to enter a host cell that do not require a specific component or action from within the host cell. An example is intracellular parasites using a method called gliding motility. This is the use of an actin-myosin motor that is connected to the intracellular parasites' cytoskeleton.