Unit 4 Adaptive immunity

Question 1

Humoral vs. Cell Mediated Immunity

Answer 1

• Humoral: protects against extracellular pathogens (B-cells activated)
• Cell: protects against intracellular pathogens (Cytotoxic T-cells activated)

Question 2

Antigens & Antibodies

Answer 2

• Antigen: any substance that triggers an immune response

- Antibodies: blood protein that is produced against a specific antigen.

Question 3

Know the types of Antibodies (mainly IgG, IgM, IgA)

Answer 3

• IgG: most abundant in serum, cross placenta, monomer (Y)
• IgA: mucus membranes, secretions, breast milk, dimer (>–
• IgM: first made, pentamer
• IgE: allergies, monomer

Question 4

4 different functions w/ antibodies

Answer 4

1. Opsinization-> “to make tasty”, enhance phagocytosis
2. Prevent adherence
3. Neutralization-> inactivate viruses and toxins
4. Agglutination-> clump the antigen together, IgM is the best

Question 5

B Cell function & activation

Answer 5

• Has MHC II receptors
• Activated because a phagocyte will present an antigen to a Helper T-cell
• Then the Helper T-cell presents that antigen to the B-cell where it can produce memory and antibodies against the virus.
• Then the antibodies go attaching to the pathogens antigens, triggering more immune responses.

Question 6

T Cells (Helper & Cytotoxic types, function & activation)

Answer 6

• MHC I receptors
• Any cell can get infected and the pathogen can take over that cell.
• If the cytotoxic T-cell recognizes the antigen presented by MHC I, then the CD8 receptor will bind
• This allows for perforins to be released
• Perforins: forms pores in the cell membrane

Question 7

How the body kills Bacteria vs. Viruses (i.e. extracellular vs. intracellular pathogens)

Question 8

Know how vaccines activate the adaptive response and generate microbial “memory”

Answer 8

The vaccines use something (subunit, inactivated agent, etc.) so that the body can create memory cells against this antigen. Then if you get infected your body will remember it

Question 9

Case study

Answer 9

• Pertussis: diphtheria, tetanus, and pertussis. “ap” portion is a surface proteins
• MMR vaccine: has measles, mumps, rubella. Live attenuated.
• COVID vaccine: nucleic acid-> uses mRNA from virus to teach our cells to make proteins against it
• Vaccines should not be administered to those who cannot receive it because of age and those who are immunocompromised
• herd immunity: majority gets the vaccine so the pathogen won’t really affect the community. (80%)

Question 10

Pertussis-> Bordetella pertussis

Answer 10

• Stain: Gram negative
• Morphology: coccibacilli
• Unique structures: exotoxins-> Tracheal-> goblet cells
• Reservoir: humans, mucus membrane of respiratory tract
• Transmission: droplet, respiratory entry
• Signs (catarrhal): runny nose, sneeze, cough (cold like signs)
• Signs (paroxysmal): rapid coughs w/ whoop
• Symptoms: nasal congestion, fatigue, difficulty breathing
• Px: DTap vax-> surface proteins with fimbriae and exotoxins
• Tx: Antibiotics-> erythromycin, fluids
• Acute

Question 11

Typhoid Fever-> Salmonella enterica

Answer 11

• Stain: gram negative
• morphology: rod
• motile: flagella erwhere
• unique structures: intracellular pathogen, membrane ruffling
• Reservoir: humans-> GI tract
• Transmission: Indirect-> vehicle (food or water), oral fecal route, shellfish
• Signs/symptoms: abdominal pain, red spots (rose spots), kidney failure, bloody stool
• Tx: antibiotics-> chloramphenicol, fluid, gall bladder removal
• Px: Vax-> whole attenuated-> orally, boiled water, wash hands

Question 12

HIV-> Human immunodeficiency virus

Answer 12

• Morphology: enveloped
• Viral genome: retrovirus-> +RNA to DNA
• Reservoir: humans-> T-helper cells
• Transmission: Direct contact-> sexual contact, contaminated needles, mucus membranes (GU)
• Initial signs and symptoms: fever, rash, headaches
• 10 yrs later Signs and symps: diarrhea, weight loss, cancer, TB
• Px: safe sex, PrEP-> taking antivirals regularly (pre exposure prophylaxis)-> helps baby not get it
• Tx: no vax, HAART-> many antivirals at once
• Latent
• Increase rates of drift (mutation)

Question 13

Hepatitis B virus

Answer 13

• Morphology: enveloped
• viral genome: ds DNA
• Reservoir: humans
• Transmission: Indirect-> needles, vertical direct-> mother to child, Horizontal direct-> sex
• Signs: vomiting, dark urine, jaundice
• Symptoms: weak, loss of appetite
• Signs and symps for chronic: liver damage, liver cancer, liver scarring
• Px: vax-> subunit spike
• Tx: acute-> fluids and rest, chronic-> antiviral: lamivudine-> genome replication inhibitor
• Chronic