Topics Exam 2

Innate Immunity

nonspecific defenses of the host, defenses against any pathogen

susceptibility

lack of resistance to a disease

immunity

ability to ward off disease

adaptive immunity

immunity or resistance to a specific pathogen

differentiate innate and adaptive immunity

innate- born with, immediate, nonspecific, no memory

adaptive- changes overtime, slower, specific, memory

First line of defense

a wall/barrier

Physical factors

skin, mucous membranes, lacrimal apparatus, saliva, urine, vaginal secretions

chemical factors

sebum, lysozyme

normal microbiota in the innate immunity

compete with pathogens, alter environment

how does the second line of defense detect invaders

toll like receptors on wbc, pathogen, TLR induce cytokines

Granulocytes

Neutrophil, Basophils, Eosinophils

Neutrophils

lilac/lavender, PMN, phagocytosis, first to arrive, 60-70%

Basophils

blue-purple, release histamine, allergic response and inflammation, 0.5-1%

Eosinophils

red/orange, little phagocytes, produce toxins and proteins against parasites, 2-4%

Agranulocytes

monocytes, dendritic cells, lymphocytes

monocytes

name changes to macrophage when it leaves blood stream, phagocyte, 3-8%

dendritic cell

from monocytes, fixed in one spot, phagocyte, adaptive response

lymphocytes

killer cells, 20-25%, t cells and b cells- adaptive response

phagocytes

cells that eat

Phagocytosis

ingestion of microbes or particles by a cell, performed by phagocytes

steps in phagocytosis

1. chemotaxis

2. adherence

3. ingestion

4. digestion

5. elimination

inflammation

local response to cell/tissue damage

Vasodilation

trigger blood vessels to dilate, increase permeability

Phagocyte migration and phagocytosis

phagocytes margination, diapedesis

tissue repair and replacement

repair and replace dead and damaged cells, stroma, parenchyma

Fever

pyrexia, high body temp, part of immune response

most frequent causes of fever

bacterial infection, toxins, viral infections, inflammation

body responds to fever

vasoconstriction, increases metabolism, shivering

as temperature returns to normal from fever

sweating, vasodilation, body temp falls

advantages of a fever

increase IL-1 activity, interferons, and transferrins

disadvantages of a fever

increase heart rate and respiratory rate, dehydration/electrolyte imbalance, acidosis, seizures/death

Complement system

antimicrobial substance, serum proteins activated in a cascade,

complement system is activated by

antigen and proteins C3, B, D, P and a pathogen

Complement system activation pathways

classical, alternate, and lectin

Effects of Complement activity

opsonization or immune adherence, membrane attack complex, inflammation

Interferons are

antiviral

Iron binding proteins

bacteria require iron, pathogens compete with host for iron

types of iron binding protein

transferrin, lactoferrin, ferritin, hemoglobin

Antimicrobial peptides

short peptides produced in response to molecules on microbes

cytokines

chemical messengers that allow cells of the immune system to communicate

sebum

oily secretions, fatty acids that inhibit bacteria and fungi

lysozyme

enzyme found in secretions, antibacterial

the lymphatic system

a network of organs, vessels, and tissues that drain excess fluid and helps your immune system fight infection

chemotaxis

chemical attraction of phagocyte to foreign material

adherence

attachment of phagocyte to foreign material

indigestion

psuedopods extend, surround and fuse to form phagosome

digestion

phagosome and lysosome fuse together, form phagolysosome

elimination

residual body, fuse with cell membrane, discharge waste

3 ways that some bacteria evade phagocytosis

kill phagocytes, escape phagosome, survive phagosome

4 signs of inflammation

swelling, red, pain, heat