Infection, the relationship between two organisms, the ... and ...

population of microbes that infect the body without causing disease

The degree of pathogenicity of an organism is it's v..

not regarded as disease agents, are called..

virulence

avirulent

Pathogenicity islands are the clusters of g... responsible for v..

the g.. encode many v.. factors (enzymes and toxins)

genes responsible for virulence

genes, virulence

endemic

epidemic

pandemic

occurs at a low level in certain geographic area

breaks out within certain population

occurs worldwide

Direct methods of disease transmission

physical contact

exposure to droplets

consumption of contaminated food or water

contact with fomites

fomites

arthropods

inanimate objects that carry disease organisms

arachnids and insects

mechanical vector

biological vector

transports on legs or other body parts

arthropod itself is diseased (malaria and yellow fever)

reservoirs are continuing natural s.. of d... o..

carrier

an organism that has r... but still sheds d... a...

source of disease organisms

recovered, disease agents

Portal of entry: site at which m.. enters h..

Portal of Exit:

microbes, host

exits the host and continues to spread disease

parasites, disease

Invasiveness: the ability of a p.. to p..t. and cause structural damage ( a v.. f..)

The v.. of a microbe also depends on its ability to produce e.. that help it counter body defences

parasite, penetrate tissues (virulence factor)

virulence, enzymes

Toxins: microbial poisons

1. E..

2. E..

Exotoxins

Endotoxins

Exotoxins are p.. m.. manufactured primarily by G..P.. b..

exotoxin produced by the botulism organism, Clostridium botulinum, is among the most l.. t..

protein molecules, Gram-positive bacteria

lethal toxins

the body responds to e.. by producing antibodies called a.. which combines with a toxin molecule and neutralizes it

the altered toxin is called a t..

 are used as vaccines against d.. and t..

exotoxins, antitoxins

toxoid

vaccine against diptheria and tetanus

Endotoxin: part of the c..w.. of g..n.. bacteria and are released only on d.. of the c..

Signs and symptoms of endotoxin prescence: increased body temp, substantial weakness and aches.

Endotoxin shock: damage to the c..s.. and s..

cell wall, gram negative, disintigration, cell

circulatory system, shock

Nonspecific resistance to disease

species immunity

skin and its extensions into the body cavity

general well being of individual

nutrition, fatigue, age, sex, climate

diseases affecting one species will not affect another

Mechanical and Chemical Barriers

- I..S..

- M..M

-Conditions of V..T..

- A...S.. made by body

Intact Skin

Mucous membranes

Conditions of vaginal tract

Antimicrobial substances

Intact Skin

keratin: p... in dead skin cells is a poor source of c... for microbes

sweat and fatty acids in sebum (oily subtance in skin glands) have a... agents

protein, carbon

antimicrobial

Stomach Acid (low p.. )

another natural form of resistance is l.. found in the saliva and tears

and the antiviral substance i.. produced by most b..c..

PH (2.0) 

enzyme lysozyme

interferon, body cells

E. M. discovered how living cells could protect themselves agains microbes

Phagocytosis: "c..e.."

 cells involved are p...

highly specialized p.. are called m..

found in the s, bm, ln, b

Elie Metchnikoff

"cell eating"

phagocytes

phagocytes, macrophages

spleen, bone marrow, lymph nodes, brain

When macrophage meets microbe:

encloses m.. with its c.m.

infolds the membrane to form p..

p. pinches off and fuses with lysosome, a cytoplasmic organelle that contributes e... for microbe's d..

encolses microbes, cell membrane

infolds membrane to form phagosome

phagosome fuses with lysosome

contributes enzymes for microbe's digestion 

Inflammation: n..s.. d..r..

Four characteristics:

R.. (red color)

c.. (warmth)

t... (swelling)

d.. (pain)

Pus: mixture of

nonspecific defensive response

rubor

calor

tumor

dolor

plasma, dead tissue cells, leukocytes,dead bacteria

Fever: n.s. r. to disease

bacteria, viruses and other microbes affect the h.. and stimulate it to raise the body temperature

nonspecific resistance

hypothalamus (base of brain)

antigens: c..s.. capable of stimulating the i..s.. and provoking an immume response.

Most are large, c.. m... not normally found in the body

most common are p.. and p..

chemical substances, immune system

complex molecules (*macromolecules)

proteins and polysaccharides (carbs)

the antigen itself does not stimulate the immune system,  

stimulation is accomplished by a..d.. or e..

contains about 6-8 a.a.m. (monosacchardie units)

Theory that prior to birth, body's own proteins and polysaccharides inactivate immune system cells

antigenic determinant, epitote

amino acid molecules

specific immunologic tolerance

The immune system: Complex collection of c.., f.. and p.. that provide an adaptive and specific r.. to a.. associated with m...

Cornerstone of the immune system

cells, factors, processes

 response, antigens, microbes

lymphocytes

L.. are distributed throughout the body and comprise the organs of the l... system including l..n.., s.., t.., a..

l.. are small cells with a l.n.

lymphocytes, lymphoid system, lymph nodes, spleed, tonsils, adenoids

lymphocytes, large nucleus

Two Types of Lymphocytes:

B Cells

T Cells

Immune system arises in fetus about __ months after conception.

Lymphocytes originate from stem cells

some stem cells develop into l..c..

move to the t.. an organ in the n.. t..

either modified by addition of s..r..p or destroyed

emerge as t.. cells and are i..

2

lymphopoietic cells

thymus, neck tissues

surface receptor proteins, destroyed

thymus cells (T cells)

immunocompetent

__ cells mature at a site that has not been determined in humans

known as bursa dervied because of the maturation site in embryonic chicks

also mature with s.r.p. on their membranes and become i..

B 

surface receptor proteins, immunocompetent

surface receptor proteins allow B and T cells to recognize e.. and bind to it

B cells oversee antibody-mediated immunity (based in a.. that react with m.., ex: b.. and m..)

 T cells oversee cell-mediated immunity, based in cells that react with eukaryotic pathogens (ex f, p)

epitote (specific antigenic determinant)

antibodies that react with microbes (bacteria and viruses)

fungi, protozoa, virus infected cells

Cell mediated immunity (overseen by T cells)

1. p.. display a... d.. on cell surfaces

2. m.. engulf the microbes or infected cells and break down a.. in the cytoplasm

3. macrophage becomes a..-p.. cell

4. travels to an organ of the l..s..

5. finds T cell with SRP that corresponds to AD and matching MHC receptors

Cell mediated immunity (overseen by T cells)

1. pathogens antigenic determinants

2. macrophages antigens

3. antigen-presenting

4.  lymphoid system

5. Surface receptor protiens, antigenic determinants

major histocompatility protein receptors

6. T cell becomes c.. T cell with a h.. T cell

7. The h.. T cell has a surface receptor protein called..

8. helper multiplies and clones, secretes h..c.p called..

9. stimulates c.. t cells to enlarge/ divide, yielding ktc

10. ktc enter lymph and blood vessels

11. receptor proteins of ctc join with ad

12. ctc releases p. a toxic protein that dissolces infected cell and l.. which enhance body's defensive capabilities

6. cyotoxic T cell, helper T cell

7. helper T cell, CD4 receptor

8. highly charged proteins, lymphokines

9. cyototoxic, killer t cells

10. killer t cells

11. cytotoxic t cells, antigenic determinants

12. cytotoxic t cell , perforin, lymphokines

Cell mediated immunity is centered on a..c..

AMI depends on activity of a.., a series of protein molecules circulating in body's fluids

attacking cells

Antibody-mediated immunity, antibodies

AMI also known as hi

In AMI, antibodies react with t.m. in blood

m.a.

v. in body fluids

humoral immunity

toxic molecules

microbial antigens

viruses

activation of B cell happens when m.. and other p.. bring a..d.. into l.. o..

macrophages have contacted helper tc

a.. and c.. of htc

htp produce lymphokines

bind to b cells and activate with l..

B cells  develop into p..c.. and produce a..

macrophages, phagocytes, antigenic determinant, lymphoid organ

 helper T cells

activation and cloning of helper T cells

helper T cell

lymphokines

plasma cells, antibodies

plasma cell: large complex cell with no s..p..r..

Produce a.. (____ per second for a life of 4-5 days)

B cells develop into MBC

surface protein receptors

2000

Memory B Cells

anitbody consists of 4 pp..c..

2 H chains

2 L chains

H chain: about 400 aa

L chaine: about 200 aa

AA in CR are virtually identical among different A..

AA in VR differ among types of A..

polypetide chains:

two heavy

Two light

Heavy: 400 amino acids

Light: 200 amino acids

amino acids in constant regions, antibodies

amino acids in variable regions, antibodies

Five types of antibodies have been identified

IgM

IgG

IgA

IgE

IgD

IgM (immunoglobulin macroglobulin)

IgG (gamma globulin)

IgM

also known as m..

first in c..

l.. antibody molecule

macroglobulin

circulation

largest

IgG (g..g..)

major c.. a..

product of m..b..c.. long term disease resistance

m.a..

(gamma globulin)

circulatory anitibody (80%)

memory B Cells,

maternal antibody

IgA

Serum IgA (..%)

s.. IgA in tears, saliva, colostrum (first milk of mother)

10%

serum

prevents gastrointestinal and respiratory illness

IgE

 plays major role in a..r..

IgD

function and significance u..

allergic reactions

unclear

neutralizing antibodies: react with viral capsoids and prevent v.. from entering h.c. and encourage p.

including a.. which offer defence against t..

viruses, host cells, phagocytes

antitoxins, toxins

antibody agglutinins reacts with a.. on surface of b.. , causing clumping, encouraging p..

precipitins react with d..a.. and convert to s.. promotes p..

complement system: series of 20 p.. that function in c.. set of r..  

antigens, bacteria, phagocytes

dissolved antigens, solid, phagocytes

proteins, cascading reactions

innate immunity

acquired immunity

born with it

begins after birth

active immunity: if it develops when the i. s responds to a. and forms antibodies

passive immunity: develops when a. enter the body from an o.s.

immune system, antigens

antibody, outside source

Naturally acquired active immunity: comes about after an illness (h b and t c)

artificially acquired a a

devlopes after exposure to a. in a v.

helper B and T cells

antigens, vaccine

Naturally acquired passive immunity: also called c..

develop when IgG antibodies pass from mother to child

artificially acquired passive immunity

injection of a-r.s into circulatory system

congenital

antibody-rich serum

Hypersensitivity reactions: overreaction of i.s. to a.

anaphylactic shock: person becomes highly sensitive to a.. after IgE attaches to white blood cells (b..) and m.. cells

can cause death from s..

immune system, antibody

antibody, basophils, mast cells

suffocation

allergy:  limited production of __ antibodies and s.. in localized areas of the body

HAy fever: t, g, w pollens

food allergies: sl, ac, n, d

IgE, sensitization

tree, grass, weed

swollen lips, abdominal cramps, nausea, diarreah

cytotoxic hypersensitivity: c..d.. reaction that occurs when __ antibodies react with antigens on the surfaces of body cells

hemolytic disease of the newborn (Rh) Rh + man and Rh - woman have a __ child

thrombocytopenia: causes i...b..c..

cell damaging, IgG

Rh+

impaired blood clotting

immune complex hypersensitivity: IgG antibodies combine excessively with a.. dissolved in body fluids

Systemic lupus erythematosus (SLE): causes b.r and spleen and kidney damage

rheumatoid arthritis: immune complexes in the j..

antigens

butterfly rash

joints and cause damage

Cellular hypersensitivity: exaggeration of c-m-i

ex: PI

overactivity of T cells to antigens cause d.s. and r.

cell mediated immunity

poison ivy

dry skin, rashes