This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Mechanism

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Phagocytosis first requires recognition of the target object. For most target micro-organisms, this entails coating with soluble substances - opsonins - which circulate throughout plasma. The opsonin-coated microbe can then adhere to the phagocyte cell surface.

Once adhered, the phagocyte begins to engulf if:

  • for the IgG opsonin, attachment is made to its receptor on the phagocyte surface
  • for the C3b complement fragment opsonin, the receptor is activated by binding to extracellular matrix such as fibronectin, or by indirect stimulation from T lymphocyte inflammatory mediators

The phagocyte slowly projects pseudopods around the target until the convalesce on the other side. The trapped organism or particle is termed a phagosome. It has a limiting outer membrane that has detached from the phagocyte's lipid bilayer.

Engulfment is usually followed by merging of the phagosome with a lysosome, so triggering phagosomal destruction.


Related pages

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page