1. Immunity

2. Infectious disease: pass between people due to germs
Noninfectious: caused by genetics or lifestyle

3. Infection Prevention
Wash your hands
Eat well-cooked food
Avoid foreign bodily fluid

4. Pathogens enter the body through an orifice (mouth, nose, genitals, wounds)
Vector: something that carries a pathogen and transmits it to healthy cells
Insects, food

5. First line of defense: Non-specific immunity
Mucous membranes
Skin
Cilia in nasal passages

6. Acidic from oil + sweat
First line of defense
Non-specific immunity

7. White blood cells! Basophil
Makes chemicals (histamine) to cause inflammation in bloodstream
Mast cell
Makes chemicals (histamine) that cause inflammation in body tissues
White blood cells!

8. Engulfs dead/damaged body cells + bacteria; phagocyte
Macrophage
Engulfs dead/damaged body cells + bacteria; phagocyte
Neutrophil
Engulf pathogen + invaders; phagocyte
Infantry
Eosinophil
Poisons parasites

9. Lymphocyte
Specific response
Destroys infected body cells + makes proteins that inactivate pathogens
T cells: helpers + killers
B cells: make antibodies

10. Immunological Proteins Complement proteins:
Punch holes in pathogens’ cell membrane
Attract phagocytes
Cause microbes to stick of blood vessels’ walls to be destroyed by phagocytes

11. Immunological Proteins Antibodies: made by B cells (lymphocytes)
Deactivate pathogen by binding its membrane proteins
Make pathogens clump so phagocytes can more easily find them
Activate complement proteins
Bacterium
Virus
Bacteria
Soluble
antigens
Foreign cell
Complement
proteins
MAC
Pore
Enhances
Phagocytosis
Leads to
Cell lysis
Macrophage

12. Antibody molecules
Antibodies are the secreted form of the B-cell receptor.

13. Immunological Proteins Interferons: produced by infected cells
Alarm call to other cells to protect themselves

14. Active/acquired immunity: body responds to a specific pathogen
Passive immunity
Genetic immunity: virus cannot infect your species
Inherited immunity: mom passes antibodies through umbilical cord or breast milk
Active/acquired immunity: body responds to a specific pathogen
Learns to fight it so upon next exposure, the immune system reacts quickly + efficiently

15. Nonspecific: 1 size fits all
Specific vs nonspecific responses
Nonspecific: 1 size fits all
Inflammation: blood vessel becomes leaky, white blood cells rush to infection site
Fever: mast cells + macrophages release chemicals that stimulate hypothalamus to increase body temp
capillary wall
extracellular space
white blood cell
37.7°C or 100°F stimulates interferon production: prevent viruses from spreading
Increase white blood cell maturity rate
High fever 39°C or 103°F = enzyme denaturation, seizure, brain damage, death

16. Specific response: customized
Antigens: marker proteins, flags on cell surface
Acquired immunity: produce memory cells to quickly attack foreign antigens if ever encountered again
Cellular + humoral immunity

17. Specific response: customized
Cellular immunity
Phagocyte engulfs intruder and presents antigens
Antigen-presenting cell
T cells activated by
antigen-presenting cell
Activated T cells
burst infected cell
Memory T cells: reserves
pathogen
antigens
T cell
receptors
activated T cells
memory T cells

18. B cell engulfs pathogens + displays antigens
Humoral immunity
B cell engulfs pathogens + displays antigens
T cell activates B cell: differentiates into memory and active B cells
Activated B cells make 2,000 antibodies/second
B cell
T cell
pathogen
memory B cells
activated B cells
antibodies

19. Tissue rejection: recipient’s immune system fights donated tissue
Immunosuppressants
Immune system attacks healthy body cells: autoimmune diseases
Severe Combined Immunodeficiency (SCID): humoral + cell-mediated branches are impaired

20. Staying Healthy
Antiseptics: chemicals (soap, vinegar, rubbing alcohol) that kill pathogens. Nonspecific
Antibiotics: target 1 bacterium/fungus. Specific

21. Antibiotic resistance: bacteria mutate, evade antibiotics
A bacterium carries genes for antibiotic resistance on a plasmid.
A copy of the plasmid is transferred through conjugation.
Resistance is quickly spread through many bacteria.

22. Vaccine: trains immune system Whole dead bacteria or viruses
Live attenuated vaccines (weakened strain)
Component vaccine: parts of pathogen containing antigen
Toxoid vaccine: inactivated bacterial toxins
Antigens in a vaccine trigger an immune response, and memory B cells are made. 1
memory B cells
A memory B cell is stimulated when the real pathogen binds to it. 2
The B cell quickly activates and makes antibodies that fight the pathogens before you get sick. 3

23. Allergy: oversensitivity to nonpathogens
Anaphylaxis: great deal of histamine causes airways to tighten, blood vessels to leak

24. Autoimmune disease: body attacks self
Type I diabetes: attack pancrease, cannot produce insulin

25. Leukemia: cancer of bone marrow
Bone marrow produces immature white blood cells
To compensate, it produces more and more
As a result, bone marrow produces fewer red blood cells + platelets
Treatment
Chemotherapy, radiation + bone marrow transplant
Risks
Graft-versus-host-disease
Opportunistic infections