SPECIFIC SPECIFIC BODY BODY

DEFENSES: DEFENSES: The The

Lymphatic Lymphatic and and

Immune Immune SystemSystem

A.  FunctionsA.  Functions  1.   Absorption and return of

excess fluid the blood stream

  2.  Absorption of fat (in the villi of the small

intestine) 3.   Immune System Function

I. Lymphatic SystemI. Lymphatic System

B. Composed of B. Composed of 1. LymphLymph – interstitial fluid2. Lymph vesselsLymph vessels a.  Closely associated with circulatory systemb.  Similar to veinsc.  Contraction of skeletal mscl causes movement of lymph fluid through valves

I. Lymphatic SystemI. Lymphatic System

B. Composed of B. Composed of 3. Lymph OrgansLymph Organs

a.a. Lymph nodesLymph nodes » Areas of Concentrated

lymphocytes and macrophages along the lymphatic vessels

» Filter lymph

I. Lymphatic SystemI. Lymphatic System

B. Composed of B. Composed of 3. Lymph OrgansLymph Organs

b.b. Bone MarrowBone Marrow produces

lymphocytesc. Spleen Spleen Serves as

Blood reservoirPurifies blood and lymph

I. Lymphatic SystemI. Lymphatic System

B. Composed of B. Composed of 3. Lymph OrgansLymph Organs

c.  Thymus causes pre-T cells to

mature to T-cells d.  Tonsils e.  Peyer’s Patches

I. Lymphatic SystemI. Lymphatic System

A. Body’s 3 Lines of DefenseA. Body’s 3 Lines of Defense

1. SkinSkin

2.2. Mucous membranesMucous membranes

3.3. Immune systemImmune system

B. Immune System isImmune System is 1. Antigen specific 2. Systemic 3. Has memory

II. Immune ResponseII. Immune Response

C. C. Kinds of Immune Response Kinds of Immune Response 1. Specific ImmunitySpecific Immunity

a. Antibodies bind only to antigen

b. B-lymphocytesB-lymphocytes – antibody prod.

c. T-lymphocytesT-lymphocytes – produce lymphokines

2.  2.  Nonspecific DefenseNonspecific Defense a. Physical barriers b. Tears c. Phagocytesd. Fever / Inflammation

II. Immune ResponseII. Immune Response

3. Humoral ImmunityHumoral Immunity a. Provided by antibodies in the

bodies fluids b. AntibodiesAntibodies

1)    Are produced by lymphocytes

2)    Circulate freely in the blood and lymph

3) Bind primarily to bacteria, toxins, free viruses

inactivates & marks for destruction

D. D. Kinds of Immune ResponseKinds of Immune Response

4. Cell Mediated Immunity Cell Mediated Immunity a. Provided by nonantibody-producing lymphocytes b. Directly attack and lyse body cells.

1)    containing viruses or parasite

2)    Cancer cells3) Foreign grafts

c. Release chemical mediators 1)   enhances inflammatory

resp.2)   Help activate lymphocytes

or macrophages

D. D. Kinds of Immune ResponseKinds of Immune Response

II. Immune ResponseII. Immune ResponseE. The Players

1. B-Cellsa.work chiefly

by secreting antibodies

b.Each B cell makes one specific

antibody

II. Immune ResponseII. Immune ResponseE. The Players

1. B-Cellsc. When a B cell

encounters its triggering antigen it

gives rise to many large plasma cells that produce that specific antibody

II. Immune ResponseII. Immune ResponseE. The Players

1. B-Cellsd. Antibody

structure 2 identical heavy chains and 2 identical

light chains shaped to form a Y.

II. Immune ResponseII. Immune ResponseE. The Players

2. T-Cellsa.Function Some help

regulate the immune system

Others are cytotoxic (directly contact infected cells and destroy them

II. Immune ResponseII. Immune ResponseE. The Players

2. T-Cellsb. Helper inducer

T cells

activate B cells and other T cells

c. Suppressor T cells

turn off or suppress immune cells

II. Immune ResponseII. Immune ResponseE. The Players

2. T-Cellsd. Cytotoxic

T cells rid the body

of cells that have been infected by viruses as well and cancer cells

II. Immune ResponseII. Immune ResponseE. The Players

4. Killer Cellsa. cytotoxic

T cells recognize

a specific antigen

b. Natural killer cellsdonot require a specific antigen

II. Immune ResponseII. Immune ResponseE. The Players

3. Cytokines diverse and

potent chemical messengers secreted by the cells of the immune system Bind to specific receptors on target cells

F. F. ImmunityImmunity

1. ImmunityImmunity – Whenever T cells and B

cells are activated, some become "memory" cells

– The next time that an individual encounters that same antigen, the immune system is primed to destroy it quickly

II. Immune ResponseII. Immune Response

F. F. ImmunityImmunity

1. Active ImmunityActive Immunity achieved by responses of

ones immune system 2. Passive ImmunityPassive Immunity

achieved with exogenous immune cells or products

II. Immune ResponseII. Immune Response

F. F. ImmunityImmunity

3. Passive Passive ImmunityImmunity

• achieved with exogenous immune cells or products

• Long term– Can be stimulated by infection also by vaccines

made from infectious agents that have been inactivated

II. Immune ResponseII. Immune Response

F. F. ImmunityImmunity

3. PassivePassive• short term

– can be transferred passively

from one individual

to anothervia antibody-containing serumacross the placenta

II. Immune ResponseII. Immune Response

FF. . Active, Passive and Active, Passive and Acquired Acquired Immunity Immunity

3. Acquired ImmunityAcquired Immunitycomes from infection or from a new born’s mothe

4. Artificial Immunity Artificial Immunity comes from immunizations

II. Immune ResponseII. Immune Response

GG. . Autoimmune diseases Autoimmune diseases

1. diseases caused by failure of the immune system to recognize “self 2.2. Examples

a.    rheumatoid arthritisrheumatoid arthritis (joints)b.    lupus erythematosuslupus erythematosus

(connective tissue)c.     GravesGraves’’ disease disease (thyroid)

II. Immune ResponseII. Immune Response

GG. . AIDS - Immunodeficiency AIDS - Immunodeficiency Syndrome Syndrome

1. Causes death 2.    Caused by Human

Immunodeficiency Virus (HIV)3. kills T-4 lymphocytes

4. T-4 lymphocytes induce B-lymphocytes to fight infection

5. Debilitated immune system

II. Immune ResponseII. Immune Response

GG. . AIDS - Immunodeficiency AIDS - Immunodeficiency Syndrome Syndrome

6. no cure for HIV

7. HIV infection causes AIDS, and AIDS allows other infections to kill the

person with the HIV infection

II. Immune ResponseII. Immune Response