Infectious diseases and vaccines

Question 1

Describe the main immune modules induced by the innate lymphoid cells.

Question 2

Some pathogens use Vectors

Answer 2

Intermediate hosts
* carry infections
* often blodsucking
* Tics, Fleas, Flies, Mosquitos

Question 3

Antibodies

Answer 3

Antibodies are protective proteins produced by your immune system. They attach to antigens (foreign substances) — such as bacteria, fungi, viruses and toxins — and remove them from your body.

Question 4

Viral infections

Answer 4

binds to a surface receptor to infect a cell
– DNA or RNA (ds or ss) -Replicate within host cell
– Genome replication may be error-prone =>mutations – Protein or lipoprotein coat
– Lipid-envelope when extra-cellular (some)

Question 5

Antibody (especially secretory IgA)

Answer 5

Blocks binding of virus to host cells; preventing infection or reinfection

Question 6

IgG, IgM, and IgA

Answer 6

Block fusion of viral envelope with host cell’s plasma membrane

Question 7

IgG and IgM

Answer 7

Enhance phagocytosis of viral particles (opsonization)

Question 8

IgM

Answer 8

Agglutinates viral particles

Question 9

Complement activated by IgG or IgM antibody

Answer 9

Mediates opsonization by C3b and lysis of enveloped viral particles by membrane-attack
complex

Question 10

IFN-g secreted by TH or TC cells

Answer 10

Direct antiviral activity

Question 11

Cytotoxic T lymphocytes (CTLs)

Answer 11

Kill virus-infected self cells

Question 12

NK cells and macrophages

Answer 12

Kill virus-infected cells by antibody-dependent cell-mediated cytotoxicity (ADCC)

Question 13

Hepatitis C

Answer 13

overcomes interferon antiviral effects by blocking/inhibiting PKR

Question 14

HSV

Answer 14

inhibits TAP activity => shutting down MHC class I presentation to CD8+ T-cells

Question 15

Influenza and HIV

Answer 15

change their surface Ag

Question 16

Virus -Evasion strategies

Answer 16

Type I and III interferon pathways
* Peptide processing and presentation in MHC class I
* Cytotoxic T lymphocyte and NK-cell response
* Modulation immunresponse by producing or blocking cytokines, chemokines or receptors
* Latency – ceasing to replicate until immunity wanes
* Survival within Macrophages
* Antigen variation

Question 17

Intracellular bacteria

Answer 17

Type1andcytotoxicimmune response
– Macrophages
– NKcells

Question 18

Extracellular bacteria

Answer 18

Type3 immune response
– Neutrophils
– Antibodies
* Neutralization & opsonization
– Complement
* opsonization & lysis

Question 19

Mycobacterium Tuberculosis

Answer 19

Intracellular bacteria
* Survive in macrophages
* Hard to eliminate – although often contained
* Th1 type immune response
* Recruits&acitvates
macrophages
* Granulomas

Question 20

Parasitic infections

Answer 20

Very broad category
Giardia lamblia
SEM 8698 lores.jpg.
(2019 Wikimedia Commons.
* From small unicellular (protozoan) to large macroscopic worms
* Ways of infection
– Water–Giardia
– Vectors–Malaria
– throughintestinaltract(food,water,feces) – Somethroughskin(egSchistosomas)
* Immune response depends on
* Mode of immune detection
* Paracitic stage * Location

Question 21

Parasitic infections - Helminths

Answer 21

Enter hosts- intestinal tracts
* Exclusively extracellular
* Type 2 immune response
– ILC2s
– IL-4, IL-5, IL13
– Mucosa
– Smooth muscle contraction
– induction of IgE
– mast cells, eosinophils
– M2 Macrophages -Alternatively activated
* Evasion:
– decrease external Ag expression
– wrap themselves in host proteins to limit immunity

Question 22

Fungal infections

Answer 22

Type 3 Immune response
* Commensal fungal organisms
– May be pathogenic if dominant
– Ie:antibacterial medications–oral candidosis (oral thrush) or vulvovaginal candidiasis (yeast infections)
* Opportunistic infections – Not normally pathogenic – Immunodeficient patients
* Neutropenia, Immunesuppression, HIV/AIDS – Candidosis
* Pneumocystis Carini * Evasion:
Candidiasis
Shankargouda et al, Fron Microbiol 2015
– –
Capsules that prevent PRRbinding
Fungi-induced expulsion from macrophages

Question 23

Vaccination

Answer 23

Aim:
– to generate protective immunity without having to go through the disease
* Active immunization
– Induce adaptive response by exposure to nonpathogenic or parts of a microbe
– Effectors:
* Antibodies
* ProtectiveTcells

Question 24

Vaccines adjuvants

Answer 24

Adjuvants are included to enhance the immune response to a vaccine
– Alum — good at stimulating TH2 but not TH1 responses
– AS04 — alum plus a TLR4 agonist
* Encourages TH1 responses
– Virosome — reconstituted viral envelope with no genetic information

Question 25

Vaccines – conjugate

Answer 25

Conjugate or multivalent vaccines can improve immunogenicity – Linking with something immunogenic

Question 26

Passive immunisation

Answer 26

Passive immunity is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system.

Question 27

Influenza vaccines

Answer 27

Antigens form 4 different virus – 2 A and 2 B
* 3 forms approved in Norway:
– Inactivated virus (most)
– Inactivated with virus (for patients >65 yrs)
– Live attenuated virus (nosespray) (children 2-17 yrs)