Intracellular pathogens

Definition

Intracellular pathogens are microorganisms, such as viruses, bacteria, and protozoa, that invade and live within the cells of a host organism. They can evade the host's immune system by hiding inside cells.

5 Must Know Facts For Your Next Test

1. Intracellular pathogens often trigger a cellular immune response involving T lymphocytes.
2. Cytotoxic T cells (CD8+) play a crucial role in identifying and destroying infected host cells.
3. Some intracellular bacteria can inhibit phagosome-lysosome fusion to survive within macrophages.
4. Helper T cells (CD4+) assist in activating other immune cells to combat intracellular infections.
5. Antigen-presenting cells present pathogen-derived peptides on MHC molecules to T lymphocytes.

Related terms

Cytotoxic T Cells (CD8+): Immune cells that destroy virus-infected or otherwise compromised host cells.

Helper T Cells (CD4+): Immune cells that assist in activating other immune responses by releasing cytokines.

Antigen-Presenting Cells:

Cells such as dendritic cells and macrophages that display antigens on their surface to activate T lymphocytes.