RNA - Retroviridae Flashcards
(95 cards)
1
Q
What do the following non defective retrovirus genes encode?
gag, pol, env
A
gag- encodes virion core protein
pol- encodes RT and IN
env- encodes envelope
2
Q
T/F: Retroviruses are more commonly to use receptor mediated penetration
A
False
3
Q
What do retroviruses use to transcrbe DNA from the RNA virion?
A
Reverse Transcriptase
4
Q
What do retroviruses lack that causes them to have a high frequency in replication?
A
3’ to 5’ exonuclease proofreading mechanism
5
Q
T/F: Endogenous retroviruses are non-pathogenic
A
True
6
Q
Which gene is lost during recombination when the retrovirus takes the proto-oncogene?
A
env gene
7
Q
T/F: All V-onc containing viruses have incomplete envelope and are replicatively defective and most assoiciate with non-defective retroviruses.
A
False
Except ROUS sarcoma virus
8
Q
T/F: Slow chronic transforming retroviruses have no v-onc genes
A
True
9
Q
Which TYPE of retroviruses leads to malignant transformation?
A
slow/chronic transforming retroviruses
10
Q
What is the etiology of Bovine Leukemia
A
Deltavirus of Retroviridae
11
Q
What is the primary mode of transmission of Bovine Leukemia
A
Through lymphocytes from one animal to the next animal
12
Q
Is the pX sequence an oncogene and what does it encode?
A
No. It encodes the tax protein
13
Q
Tax protein plays a central role in…
A
leukomogenesis
14
Q
Dairy Cattle is the main target of which virus and disease?
A
Bovine leukemia. Retrovirus
15
Q
What does BLV target?
A
B lymphocytes
16
Q
T/F: Cattle with BoLA-Aw with 7 alleles are susceptible to Bovine Leukemia
A
False. Cattle with 12 alleles
17
Q
BLV provirus is expressed into viral proteins known as?
A
blue hexagon
18
Q
What percent of cattle get persistent lymphocytosis (PL) when infected with BLV?
A
30-70%
19
Q
What occurs during the tumor phase of bovine leukemia?
A
infected B cell transforming (black) to lymphosacomas, sudden death from hemorrhage of the spleen
20
Q
Which organs can develop lymphosarcomas when infected with BLV?
A
liver, kidney, heart, lungs, abomasum
21
Q
T/F: With serology of BLV, all infected cattle will have antibodies against protein p24 and envelope gp51 in the serum
A
True
22
Q
T/F: Rectal palpation can transfer BLV
A
True, contaminated sleeves
23
Q
How do you eradicate BLV?
A
- AGID test
- Cull the positive
- Retest in 30-60 days
24
Q
A
25
What is the etiology of Feline Leukemia?
Gammavirus of Retroviruses
26
Explain the p27 protein of FeLV
gag gene, capsid protein (core), found in the cytoplasm in blood, tears, and **saliva, **major specific antigen
27
Which gene is associated with p15E of FeLV?
env gene
28
which protein is responsible for the attachment of FeLV?
gp70 protein
29
which of the four subgroups of FeLV is highly contagious?
FeLV A
30
Which subtype is the ONLY one transmitted horizontally in FeLV?
FeLV A
31
Which subgroups of FeLV is at a high risk of tumors?
FeLV A and B combo
32
T/F: FeLV is rapidly inactivated by common disinfectants
True
33
Where is FeLV most commonly found? (think of transmission)
**Saliva, **feces, urine, fleas
34
What does the FeLV virus target?
T and B lymphocytes
35
Do you find antigens in the blood of abortive infections of FeLV?
not really
36
What happens in Regressive infection of FeLV after it has infected the bone marrow?
Cats cannot eliminate it
37
T/F: Regressive infection of FeLV can result in latency
True. reactivated by immunosuppression
38
T/F Progressive infection of FeLV does not have extensive replication and persistent viremia.
False
39
oncogenic infection of FeLV
* insertion of FeLV in cellular genome near oncogene= activation
* Recombinant viruses are rearranged
* U3-LTR regoin activates NF-Kappa B (controls transcription of DNA)
40
What is FOMCA?
tumor specific antigen of FeLV
41
Majority of cats with FeLV have what type of clinical signs?
self limiting - no disease. develop neutralizing/FOMCA antibodies. may not develop viremia
42
What are the 3 forms of lymphosarcoma of neoplastic disease in FeLV?
multicentric - t cell,
thymic - t cell, kittens,
alimentary - b cell, older cats
(see ppt for details)
43
ELISA, IFA, and SNAP tests detects what in FeLV
* p27 in blood, saliva, tears
* cell membranes of NO and platelets
* serum, plasma, coagulated whole blood
respectively
44
What type of vaccine is used to treat FeLV?
Canarypox carrying FeLV gag and env genes
genetically engineered vax such as gp70 subunit vaccine
45
What are the three forms of Sporadic Bovine Leukosis
Juvenil, Thymic, cutaneous
46
T/F: FeSV has v-onc but is defective and loses its env gene
True
47
What do Fibrosarcomas express in FeSV?
FOMCA antigens
48
T/F: all strains that cause fibrosarcoma in FeSV are not pseudotypes
False
49
What is the etiology of Avian Leukosis?
Alpharetrovirus
50
What are the subgroups of Avian Leukosis and their association?
Subgroup A & B - most field outbreaks
C&D - detected infrequently
E - endognous and non oncogenic
J - myeloid leukosis
51
What happens if Avian leukemia is transmitted congenitall via the egg or within the first few days of life?
chicken develops a viremia that persists for lide due to immunogical tolerance
52
T/F: Congenital transmission is a major source of exogenous virus that can be spread to contact birds
True
53
T/F: Chickens infected with avian leukosis horizontally are most likely to develop trasient viremia and leukemia
False. They develop transient viremia and are unlikely to develop leukemia
54
What is the outcome of getting avian leukosis through vertical transmission? Congenital?
* Latency, no viremia, no leukemia
* May develop leukemia, yes virema
55
What is the primary target cell of avian leukosis
B lymphocytes of Bursa Fabricus
56
Exogenous replication competent vs endogenous replication defective of avian leukosis
endogenous - replication occurs where the c-onc gene is disturbed
exogenous - require a v-onc from a c-onc and then induce malignancytumors rapidly
57
What disease do you get with exogenous _**competent** _replication?
lymphoid leukosis (BIG LIVER DISEASE)
osteopetrosis (not neoplastic-thick leg)
renal tumors
58
What diseases do you get with exogenous replication **_defective_**?
myeloblastosis
myelocytomatosis
erythoblastosis
**\*\*outcome of above: to anemia and leukemia\*\***
59
What is the etiology of FIV?
Lentivirus
60
What are the 5 subtypes of FIV based on?
env gene
61
Which subtypes are dominant in North America?
Subtypes A and B
62
How is FIV transmitted?
Saliva- **cat bite! **(lifelong)
## Footnote
**OUCH!**
63
What is the hall mark of FIV?
Pathogenesis?
Disruption of immune system
Progressive loss of CD4 helper T lymphocytes--\>
1. decreased production secondary to the bone marrow or thymic infection
2. cytopathic effect
3. CTL mediated cytolysis or death by apoptosis
64
Aquired immunodeficiency occurs in which clinical phase of FIV?
Terminal phase
65
Persistent lymphandomegaly occurs in what clinical phase of FIV?
Latent phase
66
T/F: FIV can cause ulcerative stomatitis
True
67
SNAP detects what in FIV test?
p24 core antibody
68
T/F: there is evidence of FIV being transmitted to humans
False. FIV is highly species specific for felids
69
What is the etiology of Equine Infectious Anemia?
Lentivirus of Retroviridae
70
What is the pathogenesis of EIA?
* Persistent Ag-Ab formation result in vasculitis
--\>inflammatory changes in parenchymatous organs,
(LIVER)
* Vasculitis in CNS - ataxia, spinal leptomeningitis, encephalomyelitis
* Glomerulonephritis - immune comples mediated
71
How is EIA transmitted?
Blood cells, mechanical by tabanida, stable flies, mosquitoes, and culicoides spp.
72
Equine infection anemia results in what type of hypersensitivity?
Type II
Trigger Erythrophagocytosis by mononuclear phagocytes and complement mediated hemolysis
73
T/F: EIA virus adsorbs to RBCs and results in erythophagolysis, MAC mediated lysis, and phagocytosis by splenic MO
True
74
What are the acute clinical signs of EIA?
anemia, jaundice, blood stained feces and petechial hemorrhage of the mucosa
75
What are the chronic clinical signs if EIA?
episodal or persistent fever, cachexia, ventral edema
76
T/F: Bone Marrow Hyperplasia is a result of EIA
True
77
What does the Coggins Test detect?
It detects the p26 protein of the EIA virus.
Detects all infected animals except those in early incubation period, first 2-3 weeks after infection.
78
What is the etiology of the Caprine Arthritis Encephalomyelitis virus?
Caprine Lentivirus
79
What is the main route of transmission of CAE?
Colostrum and milk from doe to newborn
80
CAE has persistent infection of what tye of cells
MO and monocytes
81
At what age would you see arthritis in a goat infected with CAE?
1 year or older
82
Which virus would you see "big knee" and hyperplastic synovitits?
CAE
83
At what age would you see encephamlomyelitis in a goat infected with CAE?
kids 1-5 months
84
indurative mastitis (hard bag) is a clinical sign of what virus?
CAE
side note: non inflammatory indurative mastitis is a clinical sign of Maedi/Visna disease
85
T/F: Interstitial pneumonia is mostly found in kids with CAE
False. Mostly adults
86
how do you control CAE
Remove kids from infected dam at birth and feed them clean colostrum.
Side note: Colostrum from CAEV does can be used if treated at 56 C for 1 hour.
87
What is the etiology of Maedi/Visna Disease?
Ovine Lentivirus
88
How is Maedi/Visna transmitted?
* Aerosolization
* Ingestion of feces or urine contaminated water
* Colostrum and milk. Intra-uterine infection infrequent.
* Biting arthropods (from sheep with lifelong viremia)
* Contaminated surgical instruments
89
T/F: Maedi/Visna is a pathogenesis of lifelong leukocyte, cell-associated viremia
False. Lymphocytes
90
Which disease is this?
## Footnote
Sheep comes in with coughing, shortness of breath, progressive weight loss, emaciation, dyspnea.
Maedi
91
Which disease is this?
## Footnote
Sheep comes in with alowly progressive ataxia, trembling, paresis or total paralysis
Visna disease
92
T/F Maedi/Visna can result in polyarthritis
True
93
T/F: Maedi-Visna persist in presence of antibodies and cell-mediated immune response
True
94
Which of the following is INCORRECT?
## Footnote
**Control of Maedi/Visna:**
**Noninfected flock**: Quarantine and testing of incoming animals.
**Retesting** of flock every 12 months to maintain a virus-free status.
**Removal** of seropositive animals
**Isolation** of lambs at birth from seropositive ewes.
Retesting of flock every 12 months to maintain a virus-free status.
Every 6 months
95
