Viral Families

Question 1

ADENOVIRIDAE

Answer 1

Icosahedral (252)
NO envelope
linear dsDNA
e.g. Mastadenovirus

Question 2

HERPESVIRIDAE

Answer 2

Icosahedral (162)
YES enveloped
linear dsDNA
e.g. Herpesvirus
Varicella-zoster
Cytomegalovirus
Epstein-Barr virus

Question 3

POXVIRIDAE

Answer 3

Complex Structure
Yes enveloped (ether resistant)
linear dsDNA
e.g. Orthopoxvirus

Question 4

PAPILLOMAVIRIDAE

Answer 4

Icosahedral (72)
No envelope
closed circular dsDNA
e.g. Papillomavirus

Question 5

POLYOMAVIRIDAE

Answer 5

Icosahedral (72)
No envelope
closed circular dsDNA
e.g. JC virus

Question 6

PARVOVIRIDAE

Answer 6

Icosahedral (32)
No envelope
linear ssDNA
e.g. Parvoviruses

Question 7

HEPADNAVIRIDAE

Answer 7

Icosahedral (42)
Yes enveloped
circular dsDNA
e.g. Hepatitis B virus

Question 8

PICORNAVIRIDAE

Answer 8

Icosahedral (32)
No envelope
No Transcriptase
(+) ssRNA
e.g. Enteravirus (enteric)
Rhinovirus (respiratory)

Question 9

CALICIVIRIDAE

Answer 9

Icosahedral (32)
No envelope
No Transcriptase
(+) ssRNA
e.g. Calicivirus (Norwalk virus)

Question 10

ASTROVIRUS

Answer 10

Icosahedral (32)
No envelope
No Transcriptase
(+) ssRNA
e.g. Astrovirus

Question 11

CORONAVIRIDAE

Answer 11

Helical, enveloped, petal-shaped spikes
No Transcriptase
(+) ssRNA
e.g. Coronavirus

Question 12

TOGAVIRIDAE

Answer 12

Icosahedral
Enveloped
(+) ssRNA
No transcriptase
e.g. Rubivirus (rubella)

Question 13

FLAVIRIDAE

Answer 13

Icosahedral
Enveloped
(+) ssRNA
No transcriptase
e.g. Flavivirus

Question 14

BUNYAVIRIDAE

Answer 14

Helical

Enveloped

Question 15

Immunogen

Answer 15

Any compound that is capable of inducing an immune response

Question 16

Hapten

Answer 16

A compound that can interact with an Ab but is not capable of inducing an immune response on its own

Question 17

Antigen

Answer 17

Any compound that can interact with antibody or TCR

Question 18

Epitope

Answer 18

Portion of an antigen that interacts with an Ab or TCR

Question 19

Conformational epitope

Answer 19

exist only on the surface of native
folded protein

the majority of B cell epitopes

Question 20

Linear epitope

Answer 20

continuous amino acid sequence
in polypeptide

the majority of T cell epitopes

Question 21

Cross-reactivity

Answer 21

Recognition by Ab (or TCR) of an epitope other than the one that induced immune response.

Cross-reactive epitope is usually bound less well, but also may be bound better.

Question 22

Antigenic Drift

Answer 22

a mechanism for variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites.

Question 23

Antigenic Shift

Answer 23

BAD BAD BAD! the process by which two or more different strains of a virus, or strains of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains.

Question 24

Molecular mimicry

Answer 24

Cross-reacting epitopes can exist on structurally distinct molecules that share structural homology

Strepococcal pyogens –> Rheumatic fever

Question 25

Affinity

Answer 25

A measure of the strength with which a single epitope interacts with a single Ag-binding site.
[monovalent Ag]

Question 26

Avidity

Answer 26

The stability of interaction for immune complexes that consist of different antibodies (with different affinities) and multiple epitopes.
[multivalent Ag]

Question 27

Type III hypersensitivity reaction

Answer 27

Inefficient Removal of Ab/Ag Complexes Formed by Excessive Ag Can Have Serious Consequences
e.g. serum sickness