Innate Immunity

What are the three phases of protection against pathogens?

1. Recognition phase

2. Activation phase

3. Effector phase

What are the innate immune system defenses?

• Genetically programmed

• Nonspecific

• First line of defense

• Physical barriers, toxic molecules, general phagocytic cells

• Rapid response

What are the adaptive immune system defenses?

• Targets specific pathogens

• Antibodies made to find specific pathogens

• Slow long lived

What is a TLR?

Toll like receptor

• Recognition

• Participate in innate defenses

Bind to PAMPs, triggering signal transduction pathways

What do WBCs do?

Specialized for immune system functions

What do phagocytes do?

Large cells that ingest pathogens via phagocytosis

What do lymphocytes do?

They are apart of adaptive and innate immunity

• includes T and B cells

What are components of the mammalian defense-lymphatic system?

• Lymphoid tissues - thymus, bone marrow, spleen, l.nodes

• Blood plasma - solution with ions, small molecule solutes, soluble proteins

• Lymph - fluid derived from blood and other tissues, no RBCs

• Lymph nodes - sites along lymph vessels fluid is check for pathogens

What is the second line of defense?

Activation of defensive cells

• recognition by specific receptors

  • PRRs recognize pamps

What happens when the complement system is activated?

Other downstream compliment C proteins are activated in sequence

• One C protein binds to pathogen surface

• Another C protein activations inflammation

What are cytokines?

Signaling proteins

• release via PRR activation

What is inflammation?

When a tissue gets damaged, the area is isolated to stop infection spread

• cells are recruited to the site

• early responders, mast cells, release prostaglandins and histamine

How is a fever produced?

Phagocytes produce cytokines that produce fevers

• due to pyrogens

Signals brains to increase body temp to:

• accelerate lymphocyte productions

• increase phagocytosis and metalism, aka tissue repair

• some pathogens sensitive to temp