Anatomy & Physiology The Lymphatic System & Body Defenses

IMMUNE SYSTEM video:

http://www.youtube.com/watch?v=lZWOh3NEsag

Lymphatic Vessels: Form a drainage system

Drain lymph (excessive fluid from blood) and return needed materials to blood while ridding the body of undesirable materials.

If this does not function properly, edema forms (accumulation of fluid, resulting in swelling)

http://www.google.com/imgres

Lymphoedema:

http://www.clinsci.org/cs/110/0553/cs1100553f02.gif

Lymph Nodes:

Protect the body (remove bacteria & produce lymphocytes)

Macrophages (perform phagocytosis) and lymphocytes (produce antibodies) are found here

http://www.google.com/imgres

Other Lymphoid Organs:

Spleen: filters blood (of debris and old RBCs)

Thymus (shrinks as we age): produces thymosin which differentiates WBCs

Tonsils: trap & remove bacteria in the throat

Peyer’s Patches (in small intestine): capture & destroy bacteria in intestine

Appendix: aid in destroying bacteria in digestive tract

http://www.google.com/imgres

http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/9833.jpg

http://www.bocaradiology.com/Procedures/Sentinel_node/Sentinel%20Node2.jpg

http://home.xtra.co.nz/hosts/Wingmakers/image1178.gif

http://www.besthealth.com/besthealth/bodyguide/reftext/images/Thymus_spleen.jpg

http://www.medem.com/medem/images/jamaarchives/JAMA_Anatomy_Other_Spleen_JPP_01.jpg

Body Defenses:

Innate Defenses:

Nonspecific

Include: First & Second line of defenses:

Skin

Mucous membranes

Skin & Mucous secretions

Phagocytic cells

Natural Killer Cells

Antimicrobial proteins

Inflammatory Response

Adaptive Defenses:

Specific

Include Third line of defense:

Lymphocytes

Antibodies

Macrophages & Antigen-present cells

Innate Defenses:

Mechanical barriers that cover the surface of the body or cells & chemicals that protect the body

Pathogens: disease-causing organisms

http://www.google.com/imgres

Innate Defenses: First Line:

Skin

Mucous membranes

Secretions (stomach secretes HCl, saliva & tears contain lysozyme)

Innate Defenses: Second Line:

Natural Killer Cells: attack membrane of foreign invaders; release inflammatory response

Inflammatory Response: redness, heat, swelling; histamine

Phagocytes: macrophages & neutrophils “eat”

Antimicrobial Proteins: attack microorganisms directly or inhibit their reproduction

Fever: macrophages & WBCs release pyrogens (pyro = fire) producing fever

Adaptive Body Defenses: Third Line:

This line of defense is always:

Antigen specific (a specific pathogen is recognized)

Systemic (the infection site is not the only area reacting)

Has memory (if the same pathogen is encountered again, this line of D remembers & attacks stronger)

Humoral Immunity (a.k.a. antibody-mediated immunity): antibodies are found within the body fluids

Cellular Immunity (a.k.a. cell-mediated immunity): the cells provide the immunity

Antigens: molecules (proteins, nucleic acids, carbs or lipids) that are recognized as non-self (or foreign)

We have self-antigens (this is how we know our own cells)

http://www.walgreens.com/library/graphics/images/en/9071.jpg

Lymphocytes:

T cells come from the Thymus

B cells come from the Bone marrow

Active and Passive Humoral Immunity:

Active Immunity:

B cells encounter antigens and produce antibodies against them:

Naturally acquired active immunity: we receive b/c of infections

Artificially acquired active immunity: vaccinations

Passive Immunity:

Antibodies are received from human or animal serum (fluid source):

Naturally acquired passive immunity: passed from mother to fetus (lasts for first few months after birth)

Artificially acquired passive immunity: received when a person is exposed to a disease or virus (rabies, tenanus, hepatitis)

http://static.howstuffworks.com/gif/adam/images/en/hepatitis-a-immunization-vaccine-picture.jpg

Cell-Mediated Response:

Cytotoxic (killer) T cells: bind to foreign invaders and release toxic chemicals

Helper T cells: work with B cells to direct the immune system, help B & T cells divide, & help macrophages

Regulatory T cells: suppress B & T cell activity (preventing uncontrolled immune activity)

Memory Cells: long living cells that recognize antigens

Organ Transplants:

Types of organ transplants:

Autografts: tissue graft to the same person (skin graft from one are to another)

Isografts: tissue grafts from identical twin

Allografts: tissue grafts from another person (not twin)

Xenografts: tissue graft from a different species (baoon heart into human)

All patients must take immunosuppressive therapies after a graft.

Allergic Reactions:

An immune system reaction to a non-harmful substance

These sensitize lymphocytes

Allergens are antigens that trigger allergic reactions

There are 2 types:

1. Delayed-reaction allergy: due to repeated exposure to the skin (chemicals, etc) which cause dermatitis (it can take ~48hrs to occur after exposure)

2. Immediate-reaction allergy: this occurs within minutes of exposure and can be severe (cause death). B cells are activated. A variety of physiological reactions occur: BV dilation, swelling tissues, bronchial contractions, intestinal contractions, mucus production, hives, hay fever, asthma, & eczema.

Common Allergens:

http://www.vbc-genomics.com/EN/ISAC-Images/Allergie_Overview.jpg

http://apps.uwhealth.org/health/adam/graphics/images/en/19323.jpg

Dermatitis:

http://a248.e.akamai.net/7/248/430/20051209025224/www.merckmedicus.com/ppdocs/us/hcp/content/white/chapters/images/f003040.jpg

Hives:

http://apps.uwhealth.org/health/adam/graphics/images/en/2482.jpg

Autoimmunity:

When the body seemingly attacks itself,

autoantibodies are produced. This is when the

body does not distinguish between self &

nonself.

Autoimmunity is the body attacking itself.

Examples of autoimmunity are juvenile diabetes,

rheumatoid arthritis, and lupus.

Breast cancer self-exam https://www.youtube.com/watch?v=wbEQTUI2Q4E

Testicular cancer self-exam

https://www.youtube.com/watch?v=OaVloOTC1Yo

Adaptations 2017

This slide show was developed by Dana Halloran,

Cardinal Mooney High School, Sarasota, FL.

Used with her personal permission,

adapted and amended by Rosa Whiting,

Manatee School for the Arts, Palmetto, FL.