Overview of Pathogens and Immunity

Question 1

True or false? both innate and adaptive immunity can discriminate self from non-self

Answer 1

true

Question 2

True or false? Adaptive immunity is improved by vaccination

Answer 2

true

note: exposure leads to memory response the next time

Question 3

Humoral immunity is most effective against ____ pathogens

Answer 3

extracellular

Question 4

What are the three most important components of humoral immunity?

Answer 4

antibodies: highly specific
complement: series of serum proteins that lyse bacteria

C-reactive protein: general marker for inflammation/infection

Question 5

Cell-mediated immunity is responsible for elimination of what?

Answer 5

intracellular and extracellular pathogens, tumors, and damaged host cells

Question 6

The most important cells that mediate CMI are?

Answer 6

granulocytes, phagocytes, and cytotoxic cells

Question 7

These cells which mediate CMI, use enzymes and ROS to kill their targets

Answer 7

granulocytes (neutrophils, eosinophils, basophils)

Question 8

These cells which mediate CMI, engulf pathogens and kill them using enzymes and ROS

Answer 8

phagocytes (macrophages, neutrophils, eosinophils)

Question 9

These cells which mediate CMI, use enzymes to kill targets and cell surface receptors to induce target cell apoptosis

Answer 9

cytotoxic cells (NK cells, Cytotoxic T cells)

Question 10

Antibody, complement component C3b and CRP are opsonins. What are opsonins?

Answer 10

substances that coat bacteria and other particulate antigens to aid their recognition and ingestion by phagocytes

Question 11

Many bacteria have ____ that protect them from phagocytosis

Answer 11

capsules

note: opsonin coat removes protection of capsule against phagocytosis

Question 12

The simplest pathogen is the ____, an infectious glycoprotein that lacks nucleic acid, and which causes degeneration of the CNS

Answer 12

prion

Question 13

This infectious agent does not stimulate an immune response in the human host

Answer 13

prion

Question 14

this infectious agent obligates intracellular microorganisms with DNA or RNA genomes

Answer 14

virus

Question 15

This infectious agent is single-celled, eukaryotic; there are intracellular and extraceullar species

Answer 15

protozoan

Question 16

This infectious agent is multicellular nematodes (round worms), trematodes (flukes), and cestodes (tapeworms)

Answer 16

helminth

Question 17

This infectious agent is single-celled yeasts and multicellular filamentous molds; there are intracellular and extracellular species

Answer 17

fungi

Question 18

Intracellular infections are best eliminated by?

Answer 18

IFN alpha and beta (made by infected cells)
NK cells
Cytotoxic T cells

Question 19

Extracellular infections are best eliminated by?

Answer 19

Phagocytes
Antibodies of IgG, IgM, and IgA
Complement
C-reactive protein

Question 20

Helminth Infections are best eliminated by?

Answer 20

IgE

Eosinophils

Question 21

T cell deficiencies enhance susceptibility to what types of infections?

Answer 21

viral and fungal infections; cancer

Question 22

People with antibody, complement, or neutrophil deficiencies suffer from repeated _____ infections such as otitis media, sinusitis, and bacteria pneumonia

Answer 22

bacterial

Question 23

Patients rendered neutropenic by chemotherapy are highly susceptible to ___ infections

Answer 23

fungal

Question 24

A WBC count of ____-_____ is a typical normal range for adults

Answer 24

4500-11,000/mcL

Question 25

A higher than normal WBC is called leukocytosis. This can indicate what?

Answer 25

infection, inflammatory disease, leukemia, tissue trauma

Question 26

Leukopenia is lower than normal absolute WBC. It usually indicates a bone marrow failure due to what?

Answer 26

infections, radiation exposure, chemotherapeutic drug use

Question 27

This is a leukocytosis in which the increase in white blood cells is chiefly in lymphocytes (T cells, B cells, and NK cells)

Answer 27

lymphocytosis

Question 28

Lymphocytosis usually indicates what type of infection?

Answer 28

active viral infection or certain chronic intracellular bacterial infections (e.g. tuberculosis or brucellosis)

Question 29

Neutrophilia is a leukocytosis in which the increase in white blood cells is chiefly in neutrophils. This usually indicates what type of infection?

Answer 29

acute bacterial

Question 30

Neutrophilic may be due to increased bands/stabs (immature neutrophils); this is called a "____ ____"

Answer 30

left shift

Question 31

Eosinophilia is a leukocytosis in which the increase in white blood cells is chiefly in eosinophils. This usually indicates what type of infection?

Answer 31

worm infection or allergy

Question 32

``` A normal differential WBC will contain the following cell percentages: mature neutrophils immature neutrophils (bands/stabs) lymphocytes monocytes eosinophils basophils ```

Answer 32

``` mature neutrophils: 54% - 62% immature neutrophils (bands/stabs): 3% - 5% lymphocytes: 25% - 33% monocytes: 3% - 7% eosinophils: 1% - 3% basophils: 0% - 0.75% ```