Question

How do phagocytes overcome the immune protection that the bacterial capsule gives to pathogens?

a. they bind to the fc region of antibodies that opsonize the capsule.
b. they recognize bacterial cell-surface structures.
c. they bind to c3b complement factor on the surface of the capsule.
d. they release proteins that trigger apoptosis in the pathogen.

Answer 1

Phagocytes overcome the protection of bacterial capsules by binding to the Fc region of opsonizing antibodies, such as IgG, which assist in the attachment and initiation of phagocytosis. Complement system activation also contributes to the rapid clearing of pathogens.

Step-by-step explanation:

Phagocytes overcome the immune protection that the bacterial capsule provides to pathogens by using a process called opsonization. Specifically, they achieve this by binding to the Fc region of antibodies that opsonize the capsule. These antibodies, particularly IgG, bind their Fab sites to specific epitopes on the surface of pathogens. Phagocytic cells such as macrophages, dendritic cells, and neutrophils have receptors that recognize and bind to the Fc portion of the IgG molecules. This facilitates the attachment of phagocytes to the pathogens and initiates phagocytosis. Additionally, the activation of the complement system by antibodies attached to pathogens also promotes the rapid clearing of these pathogens.