Herpes

Question 1

alpha herpes virus

Answer 1

HSV, VZV

Question 2

beta herpes virus

Answer 2

CMV, HHV6, 7

Question 3

gamma herpes virus

Answer 3

EBV

Question 4

How can lytic herpes lytic replication result in transmisison?

Answer 4

Active disease or

Asymptomatic shedding

Question 5

Lytic replication in permissive cells is ______

Answer 5

cytopathic = kills cells –> disease

Question 6

Small subset of viral genes expressed but NO infxous particles are produced

Answer 6

latency

*reactivation of latent infxn is source of majority of symptomatic disease

Question 7

ALpha:

Establish latent infxn in _____ of PNS , primarily in _____ nerve ganglia

Answer 7

neurons of PNS

sensory

Question 8

Beta:

establish latent infxns in _____ lineage and ____ cells

Answer 8

myeloid and endothelial cells

Question 9

gamma:

establish latency in ____ cells, capable of transforming these cells, which are important bc:

Answer 9

B cells,
endothelial cells

transforming cells: capable of giving rise to cancer

Question 10

Herpes lytic replication cycle

Answer 10

translation:

1. Immediate early: transcribed soon after virus entry
   - set up conductive environment for viral rep to occur
   - needed for subseq expression of E and L genes
2. Early
   - encode replication enzymes and non structural proteins
3. Late
   expression
   - encode viral proteins needed for assembly and egress (get out of cell)

Question 11

Viral glycoproteins mediate ____. Are targets of _____.

Answer 11

1. cellular tropism

2. targets of adaptive immune response

Question 12

Which if the herpes virus are spread by respiratory secretions?

Answer 12

VZV

Question 13

Big herpes virus to worry about with transplants

Answer 13

CMV

Question 14

genome replication rolling circle replication

Answer 14

1. Nick on 1 strand
2. 5’–>3’ : template for replication
   “rolling circle replication”

Question 15

tx for alpha viruses and beta viruses

Answer 15

A: acyclovir
- uses viral thymidine kinase to make drug active *phosphorylated

A+B: gancyclovir

• beta viruses do not have viral TK so acyclovir wont work
• gancyclovir makes a kinase able to do first phosphorylation step

Question 16

Cidofovir

Answer 16

*cidofovir and foscarnet work downstream of phosphorylation: more side effects

Question 17

Foscarnet

Answer 17

*cidofovir and foscarnet work downstream of phosphorylation: more side effects

Question 18

Intranuclear capsidation

Answer 18

scaffold proteins transported in form cytoplasm

2. procapsid Assembly around scaffold protein
3. Becomes mature capsid
4. DNA with cleavage/packaging proteins stored in mature capside –> encapsidation

*see image

Question 19

Intranuclear histology:
acidophilic
basophilic

Answer 19

1. Acidophilic:
   Cowdry type A
   - (HSV, VZV)
2. Basophilic:
   Owl eyes
   - (CMV)

Question 20

Innate and adaptive immune response to herpes virus

Answer 20

1. Innate immune response
   - IFN/cytokine production
   - NK cell activities
2. Adaptive immune response
   - neutralizing antibodies
   - CD4+ and CD8+ T cell fxn

*herpes virus can counter each of these

Question 21

Papules are formed from:

Vesicles are formed from:

Answer 21

Cells at/above basal layer are infected and lyse –> inflammatory response –>
Papule

Lysis of cells with resultant cytokines –> inflammation –> fluid production –>
Vesicle

Question 22

Which HSV is above the belt and which below the belt?

Answer 22

Type I: above belt

Type II: below the belt
- unless its oral-genital contact

Question 23

Typical skin lesions of VZV occurs when?

Answer 23

when immune response develops

- 10-21 days

Question 24

Varicella ascends in ______ nerves from the skin and remains in _____ ganglia for life

Answer 24

sensory nerves

sensory ganglia

Question 25

tx for herpes zoster

Answer 25

acyclovir (within 3-4 days of outbreak)

Question 26

Why will VZV reactivate more easily in elderly?

Answer 26

T cell mediated immunity declines wiht age Immunosuppression

Question 27

CMV can remain latent in which cells?

Answer 27

CD34+ bone marrow progenitors Endothelial cells

Question 28

Childhood CMV can occur how?

Answer 28

1. Maternal shedding - birth canal (last trimester) - Milk

Question 29

How to differentiate between CMV and EBV?

Answer 29

CMV: monospot - EBV: monospot +

Question 30

dz of CMV

Answer 30

IgM anti-CMV antibody or PCR for CMV DNA from tissue

Question 31

therapy for disseminated CMV

Answer 31

ganciclovir (not acyclovir) resistant virus- tx with Foscarnet

Question 32

Roseola is cause by: Rubella is caused by: Rubeola is caused by:

Answer 32

Roseola (exanthem subitum) is cause by: - HHV6+7 Rubella (German measles) is caused by: - Rubella virus (togavirus) Rubeola (measles) is caused by: - paramyxovirus

Question 33

CLinical sign of roseola (HHV 6+7)

Answer 33

Rash appears as FEVER ENDS abruptly - High fever (104F) for 3-7 days, but looks good otherwise - febrile seizures possible

Question 34

How to differentiate betwn acute and latent infxn of EBV

Answer 34

Acute infxn: Ab against - 1. viral capsid antigen (VCA) 2. Early antigan (EA) Latent: 1. Epstein-Barr nuclear antigen (EBNA)

Question 35

EBNA1 EBNA2

Answer 35

EBNA1: links viral genome to cellular chromosomes EBNA2: turns on other viral latent genes and a range of cellular activation-associated genes including c-myc *closely linked to cancer

Question 36

Mononucleosis syndrome

Answer 36

1. atypical lymphocytes - activated T cells killing B cells - heterophile Ab test - kill sheep cells? 2. Fever, malase, fatigue 3. Adenopathy 4. Pharyngitis 5. Hepatosplenomegaly

Question 37

EBV associated malignancy

Answer 37

1. post-transplant lymphoproliferative disorder - lose Cytotoxic T cell response limiting activated B cell blast 2. Burkitt lymphoma 3. B cell lymphoma 4. Leiomyosarcoma 5. Hodgkin lymphoma 6. Nasopharyngeal carcinoma

Question 38

Do the majority of indiv with EBV infections experience symptoms?

Answer 38

No | - no noticeable symptoms or complications