Innate Response Flashcards

Flashcards on Innate Immune Response

Innate Immune Response

The body's non-specific defenses present from birth that provide an immediate response to pathogens without immunological memory.

There is no memory of the pathogen.

A key feature of the innate immune system is what regarding immunological memory?

Physical, Chemical, and Microbiota

What are the three types of barriers that comprise the first line of defense?

Intact skin, mucus membranes, cilia

Name three examples of physical barriers in animals.

Cuticle, Cell wall, Thorns/trichomes.

Name three examples of physical barriers in plants.

Enzymes in mucus, tears, saliva; acid in sweat; acid in stomach

Name three examples of chemical barriers in animals.

Terpenoids, Pyrethrins, Saponins

Name three examples of chemical barriers in plants.

Competition from commensal bacteria in gut and genital tract.

How do microbiota act as a barrier in animals?

By outcompeting soil pathogens or producing chemicals that repel/kill soil pathogens.

How do microbiota act as a barrier in plants?

Nonspecific immune response

What is the second line of defense characterized by?

Phagocytosis, Action by natural killer cells, Inflammation, Fever

Name four components of the second line of defense.

Neutrophils, Macrophages, Dendritic cells

Name three types of phagocytic cells.

Cancerous or infected cells no longer express MHC I on their cell membrane. Natural killer (NK) cells identify these cells.

How do Natural Killer (NK) cells identify infected cells?

Host defense against parasitic infections by releasing cytotoxic chemicals.

What is the role of eosinophils in the immune response?

Redness, Heat, Swelling, Pain, Loss of function

List the five symptoms of inflammation.

Release histamines causing vasodilation and capillary permeability to alert the immune system.

What is the function of mast cells in the inflammatory response?

Causes vasodilation of blood vessels and increases capillary permeability.

What is the role of histamine in the inflammatory response?

Vasodilation of the capillaries increases blood flow to the site of infection.

Why does vasodilation help the inflammatory response?

Protein and polysaccharide substances released from bacteria/viruses or destroyed cells that signal the hypothalamus to increase body temperature during a fever.

What are pyrogens and what do they do?

Signaling molecules released by immune cells that act on other specific immune cells to activate further immune responses.

What is the role of cytokines in the immune system?

By triggering cells to stop making viral proteins, display more MHC I markers, and attract NK cells.

How do interferons protect against viral infections?

Chemoattraction, Opsonization, Production of the membrane attack complex (MAC )

What actions do complement proteins have?