Download - Ch11 or 13 body defenses & lymphatic system
![Page 1: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/1.jpg)
Immunity and Disease
The Lymphatic System
![Page 2: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/2.jpg)
Body Defense Mechanisms
The body’s defense system Three lines of defense Distinguishing self from nonself Antibody-mediated responses and
cell-mediated responses Steps of the adaptive immune response Active and passive immunity Monoclonal antibodies Problems of the immune system
![Page 3: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/3.jpg)
The Body’s Defense System
Targets of the body’s defense mechanisms• Pathogens• Disease-causing bacteria, viruses, protozoans,
fungi, parasitic worms, prions
• Cancer cells• Once normal body cells whose genetic changes
cause unregulated cell division
![Page 4: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/4.jpg)
Overview of Body Defenses
Every day we encounter a vast number of health threats
Body defenses include physical barriers and two interacting sets of cells and proteins
![Page 5: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/5.jpg)
Three Lines of Defense Protect the Body
Physical barrier to invasion• Intact skin• Linings of body cavities and tubes
Innate immune system• General, immediate response to antigens• Does not target specific intruders
Adaptive immune system
![Page 6: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/6.jpg)
![Page 7: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/7.jpg)
We Are Born with Some General Defenses and Acquire Other, Specific Ones (1)
Pathogens• Viruses• Bacteria • Fungi• Protozoa• Parasitic worms
Antigens• Proteins• Lipids• Oligosaccharides
![Page 8: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/8.jpg)
We Are Born with Some General Defenses and Acquire Other, Specific Ones (2)
Immunity• Innate immunity• Preset responses• Immediate response• Carried out by some white blood cells and
plasma proteins
• Adaptive immunity • Slower response• Carried out by lymphocytes and proteins
• Every adaptive response leaves behind cells that “remember” a pathogen basis of immunizations
![Page 9: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/9.jpg)
White Blood Cells
The defenders
Produced by stem cells in bone marrow
![Page 10: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/10.jpg)
Phagocytes
Type of WBC
Releases several types of cytokines
• “Cell movers” that promote and regulate immunity• Interleukines• Interferons
![Page 11: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/11.jpg)
White Blood Cells & Their Chemicals Are the Defenders in Immune Responses (1)
Phagocytic white blood cells release chemical signals and aid the immune system• Cytokines• Interleukins• Interferons• Tumor necrosis factor• White blood cell enzymes
Another chemical weapon• Complement system (proteins)• ~30 proteins• Act as antimicrobials- flag microbes for destruction!
![Page 12: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/12.jpg)
White Blood Cells & Their Chemicals Are the Defenders in Immune Responses (2) Types of white blood cells: Neutrophils (2/3rds of our WBC’s)
Basophils (release histamines)
Mast cells (release histamines)
Macrophages (engulf cells)
Eosinophils (target worms, fungi, etc)
Dendritic cells (alert immune system when antigen is in tissue fluid in skin and body linings
B and T Lymphocytes• B cells and T cells: only cells with specific receptors
Natural killer cells (NK cells- destroy cancer cells & cells infected by viruses
![Page 13: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/13.jpg)
The Lymphatic System Lymphatic system• Picks up fluid lost from the capillaries and returns it to
the blood• Defense• Consists of: drainage vessels, lymphoid organs, and
lymph tissues
Lymphoid organs• Spleen• Lymph nodes• Others
Lymph Fluid identical to interstitial fluid
![Page 14: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/14.jpg)
Lymphatic System
Elephantiasis • A condition in which
parasites block lymphatic vessels, preventing the return of fluid to blood
• Results in massive swelling, darkening, and thickening of the skin in the affected area
![Page 15: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/15.jpg)
Lymphatic System
Components of the lymphatic system• Lymph• Fluid identical to interstitial fluid
• Lymphatic vessels• Vessels through which lymph flows• Have one-way valves to prevent backflow
• Lymphoid tissues and organs
![Page 16: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/16.jpg)
Fig. 9-2, p. 158
Tonsils Defense against bacteria and other foreign agents
Right Lymphatic Duct Drains right upper portion of the body
Thymus Gland Site where certain white blood cells acquire means to chemically recognize specific foreign invaders
Thoracic Duct Drains most of the body
Some Lymph Vessels Return excess interstitial fluid and reclaimable solutes to the blood
Some Lymph Nodes Filter bacteria and many other agents of disease from lymph
Spleen Major site of antibody production; disposal site for old red blood cells and foreign debris; site of red blood cell formation in the embryo
Bone Marrow Marrow in some bones is production site for infection-fighting blood cells (as well as red blood cells and platelets)
Stepped Art
![Page 17: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/17.jpg)
![Page 18: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/18.jpg)
The Lymph Vascular System Functions in Drainage, Delivery, and Disposal
Lymph capillaries at the start of the drainage network
• Collect water & solutes
Merge into larger vessels containing smooth muscles and valves
Transport material to ducts of CV system
![Page 19: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/19.jpg)
Lymph Capillaries Collect Fluid and Direct It through Lymph Nodes
![Page 20: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/20.jpg)
Lymph
Lymph fluid returns to blood via large lymph vessels that drain into veins in the lower neck
![Page 21: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/21.jpg)
Lymphoid Organs and Lymphatic Tissues Are Specialized for Body Defense Lymph nodes• Lymphocytes and macrophages clear the lymph of
bacteria and other foreign substances
Spleen• largest lymphatic organ• Filters blood• Major site of antibody production• Storage reservoir of red blood cells and
macrophages
Thymus • Site of T cell multiplication and specialization
![Page 22: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/22.jpg)
Take Home
• What are the functions of the lymphatic system?
![Page 23: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/23.jpg)
Surface Barriers
Pathogens usually cannot get past the skin or the linings of other body surfaces such as
the digestive tract
![Page 24: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/24.jpg)
Surface Barriers (1)
Bacteria are normal inhabitants of the body• Roles of bacteria• On the skin• In the mucosal lining of the digestive tract• In the vaginal mucosa, e.g., Lactobacillus
Effect of antibiotics on normal microbial inhabitants, e.g., Lactobacillus
Athlete’s foot
![Page 25: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/25.jpg)
Vaginal Yeast Infection
http://yeastinfectionnomore.atarh.com/
![Page 26: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/26.jpg)
Surface Barriers (2)
Inner walls of the respiratory airways• Sticky mucus• Cilia• Lysozyme• Enzyme that fights bacteria
More protection found in:• Tears• Saliva• Gastric fluid• Urine has low pH and flushing action• Mild diarrhea
![Page 27: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/27.jpg)
![Page 28: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/28.jpg)
Innate Immunity
Phagocytosis, …inflammation, …and fever… …are the body’s “off-the-shelf” mechanisms that
act at once to counter threats in general and prevent infection
![Page 29: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/29.jpg)
The Mighty Macrophage!
![Page 30: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/30.jpg)
Innate Immunity (1)
Once a pathogen enters the body: Macrophages arrive 1st (usually)• Release cytokines if they detect antigen• Cytokines are chemical signals that attract
dendritic cells, neutrophils, and more macrophages Complement molecules activated
• Attract phagocytes (such as macrophages & neutrophils)• Bind to the pathogen• May form membrane attack complexes• Trigger inflammation
![Page 31: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/31.jpg)
Inflammatory Response
Inflammatory response• Destroys invaders and helps repair and restore
damaged tissue • Four signs• Redness• Heat• Swelling• Pain
![Page 32: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/32.jpg)
Inflammatory Response
Redness• Mast cells release histamine, which causes blood
vessels to dilate• Blood flow to the area increases, delivering
defensive cells and removing dead cellsand toxins
![Page 33: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/33.jpg)
Inflammatory Response
Heat• Temperature rises as a result of increased blood
flow• Speeds healing and activities of
defensive cells
![Page 34: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/34.jpg)
Inflammatory Response
Fever • An abnormally high body temperature• Caused by pyrogens• Chemicals that reset the brain’s thermostat to a
higher temperature
• A mild or moderate fever helps fight bacterial infection
• A very high fever (over 105F or 40.6C) is dangerous
![Page 35: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/35.jpg)
Inflammatory Response
Swelling• Histamine causes capillaries to become leaky
and fluid seeps into tissues• Fluid brings clotting factors, oxygen,
and nutrients
![Page 36: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/36.jpg)
Inflammatory Response
Pain• Can be caused by • Excess fluid• Bacterial toxins• Prostaglandins
![Page 37: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/37.jpg)
Acute sudden inflammation
Activated complement and cytokines trigger this fast, general response to tissue invasion
Symptoms are redness, swelling, warmth, and pain, all caused by this series of internal events
![Page 38: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/38.jpg)
Acute Inflammation Is a General Response to Tissue Damage
Histamines ↑
![Page 39: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/39.jpg)
Innate Immunity (2) Symptoms of inflammation include redness, swelling,
warmth, and pain
Internal events of inflammation• Mast cells release histamine• Arteriole vasodilation• Fluid and plasma leak out of capillaries leading to edema
(swelling)• Bacteria attacked• Clotting factors- wall off inflamed area• Fever- develops when cytokines stimulate brain to
release prostaglandins• Prostaglandins are signaling molecules that raise set point on
hypothalamic thermostat
![Page 40: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/40.jpg)
Adaptive Immunity
![Page 41: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/41.jpg)
Overview of Adaptive Defenses
When physical barriers and inflammation don’t prevent an invasion, the adaptive immune system is mobilized
![Page 42: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/42.jpg)
Adaptive Immunity Has Three Key Features
Adaptive immunity mobilizes B and T cells1. Specificity- receptors for 1 kind of antigen form
2. Diversity- collectively, these cells may have receptors for ~a billion different specific threats
3. Memory- some of the B and T cells are held in reserve for future battles
Effector cells• Respond immediately to destroy pathogen
Memory cells• Set aside for a second or third encounter
![Page 43: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/43.jpg)
Distinguishing Self from Nonself
T cells and B cells• B cells and T cells that respond to a particular
antigen divide repeatedly, forming two cell lines• Effector cells
• Short-lived cells that attack the invader
• Memory cells• Long-lived cells that remember the invader and
mount a quick response when it is next encountered
![Page 44: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/44.jpg)
Activated Lymphocytes Produce Effector Cells and Memory Cells
![Page 45: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/45.jpg)
Antibody-Mediated Responses and
Cell-Mediated Responses
![Page 46: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/46.jpg)
B Cells and T Cells Attack Invaders in Different Ways B cells• Produced in bone marrow, sent to lymphatic
system• Produce antibodies; antibody-mediated
immunity- instead of direct engagement, produce protein antibodies
T cells• Produced in bone marrow and go to the thymus
gland for development• Cytotoxic T cells; cell-mediated immunity-
involves direct engagement
• Helper T cells- have both types of responses
![Page 47: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/47.jpg)
![Page 48: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/48.jpg)
Steps of the Adaptive Immune Response
1. Threat• Foreign organism or molecule (an antigen) enters
the body
2. Detection• Macrophage detects foreign organism or
molecule and engulfs it
![Page 49: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/49.jpg)
Steps of the Adaptive Immune Response
3. Alert• Macrophages present antigens to helper
T cells• Macrophages are antigen-presenting cells• Helper T cells are the main switch for the adaptive
immune response
![Page 50: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/50.jpg)
![Page 51: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/51.jpg)
Steps of the Adaptive Immune Response
4. Alarm• Helper T cells activate appropriate B cells and T
cells to destroy the specific antigen• When activated, these cells divide to form clones
of cells designed to eliminate the specific antigen from the body
![Page 52: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/52.jpg)
Steps of the Adaptive Immune Response
5. Building specific defenses • B cells form plasma cells that secrete antibodies
into the bloodstream that bind to antigens• T cells form cytotoxic T cells that attack
![Page 53: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/53.jpg)
Steps of the Adaptive Immune Response
6. Defense: The cell-mediated response• An effector cytotoxic T cell releases perforins,
which cause holes to form in cells with the particular antigen
![Page 54: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/54.jpg)
Steps of the Adaptive Immune Response
7. Continued surveillance Immunological memory allows for a more rapid
response on subsequent exposure to the antigen Primary response
Occurs during body’s first encounter with a particular antigen
Antibody concentration rises slowly Secondary response
Occurs during subsequent encounter with that antigen
Strong and swift due to the large number of memory cells programmed to respond to that particular antigen
![Page 55: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/55.jpg)
![Page 56: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/56.jpg)
![Page 57: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/57.jpg)
B and T Cells
![Page 58: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/58.jpg)
B & T Cells
When mature, most move into lymph nodes, the spleen, and other lymphoid tissue
Remember- two different responses occur: 1) Antibody- mediated
2) Cell-mediated
![Page 59: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/59.jpg)
How Do B & T Cells Learn?
They study hard!• Study groups• Biojeopardy learning games
Involves MHC markers• Major histocompatability complex genes
![Page 60: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/60.jpg)
MHC Markers Label Body Cells as Self
MHC markers• Major Histocompatibility Complex genes code for
these proteins• Some of these proteins stick out of cell
membranes• T cells have receptors that recognize them
![Page 61: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/61.jpg)
![Page 62: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/62.jpg)
Antibody-Mediated Immunity: Defending against Threats Outside Cells
Different kinds of antibodies have roles in body defenses
5 classes of antibodies
![Page 63: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/63.jpg)
Antibodies Develop While B Cells Are in Bone Marrow
B cell in bone marrow develops antibodies
Binding of antigens• Copies of antibodies made by B cell, migrate to and
stick out of plasma membrane like ‘bristles’
![Page 64: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/64.jpg)
Antibodies Can Bind to Antigens
Fig. 9-12, p. 164
binding site for antigen binding site for antigen
antigen on bacterial cell (not to scale)
binding site on one kind of antibody molecule for a specific antigen
Stepped Art
Typical Y-shape of simple antibody
![Page 65: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/65.jpg)
There Are Five Classes of Antibodies, Each with a Particular Function
Immunoglobulins (Igs)• Proteins produced by B cells; various shapes• Result from gene shuffling while B cell matures
during immune response
• Antigen-binding sites; other sites with special roles
Types of Igs (pg165)
• IgM• IgD• IgG• IgA• IgE
![Page 66: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/66.jpg)
Cell-Mediated Responses: Defending against Threats Inside Cells
Responses by antibodies can’t reach threats inside cells
Accordingly, when cells become infected or altered in harmful ways, other “warrior” cells must come to the defense
![Page 67: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/67.jpg)
Cell-Mediated Responses
Starts when an antigen presenting cell (APC) presents an antigen to a T cell
Role of:• Helper T cells and cytotoxic T cells specific response• NK cells and macrophages more general response
Target: viruses, bacteria, some protozoa and some fungi, and cancerous cells
Apoptosis
![Page 68: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/68.jpg)
Protozoans
Giardiasis is an infection of the small intestine caused by a microscopic organism (protozoa), Giardia lamblia.Abdominal pain, Diarrhea, Gas or bloating, Headache, Loss of appetite, Low-grade fever, Nausea, Swollen or distended abdomen, Vomiting
![Page 69: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/69.jpg)
T Cells Are the Warriors in Cell-Mediated Immune Responses
![Page 70: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/70.jpg)
T cell (orange) killing a cancer cell (magenta).
![Page 71: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/71.jpg)
![Page 72: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/72.jpg)
Helper T Cells
Their cytokines stimulate NK cells
NK cells don’t need an antigen
They simply attack any body cell that has too few or altered MHC markers, or that antibodies have tagged for destruction
They also kill cells flagged with chemical “stress markers” that develop when a cell is infected or becomes cancerous
![Page 73: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/73.jpg)
A Cytotoxic T Cell Touch-Killing a Tumor Cell
Release chemicals that kill on contact.Also release chemicals that cause genetically programmed cell death- apoptosis.
![Page 74: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/74.jpg)
Cytotoxic T Cells Cause the Body to Reject Transplanted Tissue
MHC markers on donor cells recognized as antigens by recipient cells
Best donors have similar genetic makeup and compatible blood type with recipient
Recipient takes immuno-suppressing drugs and often antibiotics to control infections
Transplanted tissues of the eye and testicles do not provoke an immune response
![Page 75: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/75.jpg)
Immunological Memory
The memory cells produced during an adaptive immune response can provide many years of immunity to a pathogen
![Page 76: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/76.jpg)
Immunological Memory
Memory cells form during primary (first) immune response• Circulate for years, even decades• Patrolling battalions
Even more memory T and plasma cells form during a second adaptive response
Memory cells determined by the type of antigen exposure
![Page 77: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/77.jpg)
Memory Cells Allow the Body to Mount a Faster, Stronger Immune Response
![Page 78: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/78.jpg)
Applications of Immunology
Modern science has developed powerful weapons that can enhance the immune system’s functioning or harness it in new ways to treat disease
Vaccine primary immune response to antigen Booster secondary immune response; more
effector & memory cells form that can provide longer lasting protection
![Page 79: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/79.jpg)
Immunization Gives “Borrowed” Immunity
Immunization• Vaccine: first injection + “booster shot”• Killed or extremely weakened pathogens• Inactive forms of natural toxins• Transgenic viruses
Passive immunization• Injections of purified antibodies• Does not confer memory cells though
Adverse effects of vaccines
![Page 80: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/80.jpg)
Passive Immunity to Infectious Disease 1955
http://www.youtube.com/watch?v=9Bm2fnCTaMg
![Page 81: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/81.jpg)
WHO: Prevent. Protect. Immunize.
http://www.youtube.com/watch?v=sGKrs1ED_rw
![Page 82: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/82.jpg)
Disorders of the Immune System
In allergies, harmless substances provoke an immune attack
![Page 83: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/83.jpg)
In Allergies, Harmless Substances Provoke an Immune Attack (1)
Common allergens• Pollen• Variety of foods and drugs• Dust mites• Fungal spores• Insect venom• Ingredients in cosmetics
Allergy• Response and severity
![Page 84: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/84.jpg)
The Basic Steps Leading to an Allergic Response
Role of IgE antibodies
![Page 85: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/85.jpg)
In Allergies, Harmless Substances Provoke an Immune Attack (2)
Symptoms of allergies vary• Inflammation of mucus membranes• Constriction of airways• Stuffed sinuses, drippy nose, and sneezing in
hay fever• Vomiting• Diarrhea
Anaphylactic shock• Whole-body allergic response• Can be fatal
![Page 86: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/86.jpg)
Autoimmune Disorders Attack “Self”
Autoimmune disorders• Rheumatoid arthritis• Type I diabetes• Insulin secreting cells of pancreas attacked
• Systemic lupus erythematosus
Immune systems “weapons” unleashed upon own body
More common in women- is receptor for estrogen involved??
![Page 87: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/87.jpg)
Immune Responses Can Be Deficient
Immunodeficiency • Weakened or missing immune system
Severe combined immune deficiency (SCID)• Short supply of B and T cells• Usually inherited• Usually infants die early
HIV and AIDS
![Page 88: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/88.jpg)
HIV and AIDS
HIV, the human immunodeficiency virus, cripples the immune system by destroying lymphocytes
![Page 89: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/89.jpg)
HIV and AIDS
AIDS caused by infection with HIV
HIV kills lymphocytes• Macrophages, dendritic cells, and helper T cells• Can get in via certain type of surface receptor
Diagnostic signs of AIDS• Severely depressed immune system• Positive HIV test• “Indicator disease”- types of pneumonia, recurrent
yeast infections, cancer, drug-resistant TB
![Page 90: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/90.jpg)
Particles bursting the cell membrane
![Page 91: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/91.jpg)
HIV Life Cycle
http://www.youtube.com/watch?v=9leO28ydyfU
![Page 92: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/92.jpg)
Pathogens Spread in Four Ways
Infections that can threaten health spread in 4 predictable ways and occur in 4 predictable patterns
1. Direct contact
2. Indirect contact
3. Inhaling pathogens
4. Contact with a vector
Nosocomial infection: acquired in a hospital
![Page 93: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/93.jpg)
![Page 94: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/94.jpg)
Many Infections Are Spread by Contact or When a Pathogen Is Inhaled
![Page 95: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/95.jpg)
Diseases Occur in Four Patterns
Epidemic• Disease rate increases to a level above what
we would predict Pandemic• When epidemics break out in several countries
around the world Sporadic disease• Irregularly breaks out and affects relatively few
Endemic disease• Occurs more or less continuously
![Page 96: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/96.jpg)
Virulence Is a Measure of Pathogen Damage
Virulence of a pathogen
How fast can the pathogen invade the tissues?
How severe is the damage it causes?
Which tissues are targeted?
![Page 97: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/97.jpg)
Fig. 9-25a, p. 175
Respiratory tract Preventative measures: • Hand washing • Cover mouth when coughing or sneezing • Proper disposal of used tissues • Vaccination programs
GI tract Preventative measures: • Hand washing • Proper food storage, handling, and cooking • Good public sanitation (sewage, drinking water)
Blood Preventative measures: • Avoid/prevent needle sharing/ IV drug abuse • Maintain pure public blood supplies • Vaccination programs against blood-borne pathogens (e. g., hepatitis B)
Skin Preventative measures: • Hand washing • Limit contact with items used by an infected person
![Page 98: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/98.jpg)
The Human Body’s Three Lines of Defense against Pathogens
![Page 99: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/99.jpg)
Introduction to how the immune system works | Biology | Anatomy | Immunology
http://www.youtube.com/watch?v=IWMJIMzsEMg
![Page 100: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/100.jpg)
Cell Mediated Immune Response
http://www.youtube.com/watch?v=1tBOmG0QMbA
![Page 101: Ch11 or 13 body defenses & lymphatic system](https://reader036.vdocuments.site/reader036/viewer/2022081511/556b8860d8b42a6c7c8b503c/html5/thumbnails/101.jpg)
Antibody Mediated Immune Response
http://www.youtube.com/watch?v=hQmaPwP0KRI