Mouse RNA Viruses Flashcards
(133 cards)
1
Q
What mouse virus is in the arterivirus family?
A
Lactate Dehydrogenase Elevating Virus
2
Q
What are the requirements for paralytic syndrome to develop with Lactate Dehydrogenase Elevating virus?
A
Immune suppression, Murine Leukemia virus, neurotropic LDV, homozygous for Fv-1 allele in that strain (C58, AKR, ICR-scid among others)
3
Q
What cell type does LDV have an affinity tropism for?
A
Macrophages expressing F4/F8
4
Q
Does LDH elevating virus cause a persistent infection?
A
yes, lifelong viremia!
5
Q
Is LDH elevating virus transmitted vertically?
A
yes
6
Q
Why is increased LDH a sign of LDH elevating virus?
A
the virus prevents clearances of enzymes via reticuloendothelial system
7
Q
Which mouse strain has the highest increased LDH enzyme when infected with LDH elevating virus?
A
SJL
8
Q
If LDH elevating virus is detected in cell lines, what should be done?
A
passage them in athymic rats to rid the virus, they do not have the correct macrophages to propagate the virus
9
Q
How can LDH elevating virus be detected?
A
Serology is poor because antigen complexes with antibodies, PCR is best, or innoculate naive mice and test LDH 4d later
10
Q
Which LDH isozyme is increased with infection from LDH elevating virus?
A
LDH-V (there are 5 isozymes in mice)
11
Q
What clinical signs are seen with LDH elevating virus infection?
A
no clinical signs unless all requirements met for paralytic syndrome/poliomyelitis.
12
Q
How is LDH elevating virus transmitted?
A
infected biologics, bite wounds, has very inefficient transmission from cage to cage and even contact sentinels
13
Q
What virus commonly contaminates mouse biologics?
A
LDH elevating virus
14
Q
Are B6 mice affected by LDH elevating virus?
A
yes, mild neuro lesions are seen in this strain
15
Q
Are arteriviruses enveloped?
A
yes
16
Q
What effects does LDH elevating virus have on research?
A
Suppresses CMI, can alter tumor growth, reduce autoantibody formation
17
Q
When is the LDH elevating virus cleared in infected mice?
A
never, life long viremia
18
Q
What lesions are seen in mice naturally infected with LDH elevating virus?
A
none
19
Q
What mouse virus is in the arenaviridae family?
A
LCMV
20
Q
Why is LCMV such a problem in a mouse colony?
A
in utero transmission leads to persistently infected mice that do not seroconvert
21
Q
Why is LCMV a problem in mouse biologics?
A
It has no cytopathic effects and can go undetected
22
Q
What other species can be infected with LCMV besides mice?
A
hamster, GPs, NHP (Percy says NOT rats unless experimental infection)
23
Q
What clinical signs are seen in mice infected in utero with LCMV?
A
runting but usually not until later in life when glomerularnephritis develops from immune complex deposition.
24
Q
What clinical signs are seen in humans exposed to LCMV?
A
flu like signs, CNS signs possible
25
If LCMV doesn't cause cytolysis, why are clinical signs seen with infection?
CMI response leads to tissue damage of infected animals
26
Neurologic signs are seen during what type of LCMV infections?
Experimental only with intracerebral inoculations of mice. Tremors and seizures when suspended by the tail.
27
What species can transmit LCMV?
mice and hamsters
28
If an immune competent adult mouse is exposed to LCMV, what happens?
usually asymptomatic and clears infection
29
What species is the primary source of human infection with LCMV?
Hamsters
30
Will LCMV spread quickly through a colony?
No, but can go undetected if breeding continues due to in utero transmission.
31
What sites are affected by immune complex deposition secondary to LCMV infection?
Kidney, choroid plexus, synovial membranes
32
What type of monitoring is used for LCMV?
Serology, but fetal infections will not seroconvert. Direct contact sentinels best.
33
If LCMV is detected in a colony, what is recommended for control?
test and cull for irreplaceable animals, depopulate for reproducible due to zoonosis
34
LCMV clinical signs in pups that have been infected are secondary to what?
endocrine disorders (decrease GH, diabetes, hypothyroid)
35
Which haplotype determines susceptibility to LCMV?
H2 - C3H/He resistant! SWR and C3H.Q susceptible
36
How is LCMV transmitted in utero?
Present in ovaries of infected dams
37
is LCMV an enveloped or nonenveloped virus?
enveloped
38
LCMV serves as a model for what disease process?
viral induced T cell mediated injuries and immune complex disease
39
Sendai virus is in what virus family? enveloped or non enveloped?
Paramyxovirus, enveloped
40
List that viruses show no cytopathic effect in cultured cells?
Sendai, Pneumonia virus of mice, and LCMV
41
What are the clinical signs of Sendai virus infection?
Pneumonia, dyspnea
42
Which alveolar cells are more affected with Sendai infection?
Type II pneumocytes
43
Does Sendai virus have rapid cage to cage spread?
yes, highly contagious and spread via aersolization
44
Which mouse strain is highly susceptible to Sendai virus infection?
DBA/2, 129, C3H
45
Why do some immune deficient strains develop wasting syndrome instead of diffuse pneumonia with Sendai virus infection?
T cells involved in CMI that cause tissue necrosis and recovery, without T cells to cause disease... athymics etc have slower progression of disease
46
Which age is more susceptible to lethal Sendai infection?
suckling mice
47
Which mouse strains are resistant to clinical Sendai infection?
B6, AKR, SJL, Swiss
48
What other species in a facility can contract Sendai during a mouse outbreak?
Rats, GP, Hamsters (likely all rodents)
49
How is Sendai virus perpetuated in a colony?
By bringing in new nonimmune animals. Maternal immunity is protective against infection.
50
Does Sendai virus cause persistent infection?
No if immune competent strain
51
Which virus is described as showing meaty plum colored lung lobes on pathology?
Sendai (consolidated, serosanguinous exudate, can have sharp demarcation between normal vs. abnormal)
52
Name two viruses that may show syncytia at site of lesions on histopath?
Sendai, MHV (I think there is one more??)
53
How can Sendai virus be diagnosed?
Serology within one week post infection
54
If you suspect Sendai virus as cause of respiratory signs in a mouse, what other differentials should be on the list?
Pneumonia virus of mice, mycoplasma pulmonia, bacterial infections (C. kutscheri), mild MHV.
55
If there is an outbreak of Sendai virus in a mouse colony, how is it controlled?
quarantine, stop all breeding x4-6wks. Infection will clear, self limiting in surviving animals.
56
What two viruses can cause clinical signs in immunecompetent mouse strains?
Sendai and Ectromelia
57
A recently ill mouse is undergoing necropsy, you find grayish areas of lung grossly, hyperplastic bronchiolar epithelium with cuboidal alveoli, and squamouse metaplasia of respiratory epithelium and fibrosis, what infection did this mouse likely recover from?
Sendai virus
58
Pneumonia Virus of Mice is in what virus family? enveloped or nonenveloped?
Paramyxovirus, enveloped
59
List three viruses that are noncytopathic in culture?
Pneumonia virus of mice, Sendai, LCMV
60
Which of the following is more contagious, Sendai or Pneumonia VIrus of Mice?
Sendai, PVM spreads slower.
61
Describe the differences when immunecompetent mice are infected with Sendai vs. Pneumonia virus of mice.
Sendai will show clinical respiratory signs, PVM is asymptomatic in immune competent animals
62
Is pneumonia virus of mice a persistent infection?
Only in immune deficient animals
63
What are the path lesions of pneumonia virus of mice in immunecompetent vs. immunedeficient animals?
none in immune competent animals
| Interstitial pneumonia, rhinitis in immune deficient
64
What cell line is used for in vitro work with Pneumonia Virus of Mice?
BHK-21 (baby hamster kidney)
65
Is serology helpful for pneumonia virus of mice
yes, how it's commonly diagnosed.
66
Which strain is resistant to infection with pneumonia virus of mice?
SJL (B6 considered intermittent susceptibility)
67
Which strain is highly susceptible to infection with pneumonia virus of mice?
129Sv, DBA/2, C3H
68
Which mouse strain will not seroconvert to pneumonia virus of mice?
Athymic nude mice
69
What lesion will help ddx pneumonia virus from sendai virus on histology?
Sendai will have bronchiolar hypertrophy and PVM will not
70
Besides reovirus, what other mouse virus is in the reoviridae family?
Rotavirus, EDIM
71
When is clincial disease seen with reovirus infection?
only in neonates, adults subclinical
72
Mice in your colony have oily hair, icterus, and CNS signs. What viral infection should be suspected?
Reovirus (MHV rule out)
73
What organs are affected with reovirus infection in neonatal mice?
Liver, Heart, Brain, Pancreas
74
What is the best location in the heart to identify lesions of reovirus infection?
necrosis best seen in the papillary muscles of the left ventricle
75
Are survivors of reovirus infection carriers?
the carrier state is unknown for this virus, so continued testing should occur on recovered mice (via MAP or sentinels)
76
Which virus shows dense eosinophilic material in liver lesions similar to councilman bodies?
Reovirus -3
77
Is reovirus transmitted vertically?
no
78
Some weanling mice are runted with alopecia after recovering from clinical signs related to liver and brain disease, what viral infection should be suspected?
reovirus - alopecia is seen with recovery
79
If you suspect reovirus infection in mice, what is the best method of diagnosis?
serology often used, IHC on tissues or PCR to confirm
80
At what age are mice affected by EDIM?
81
How can EDIM be differentiated from other severe diarrhea diseases?
EDIM mice will have milk in the stomach, they continue to nurse. Other more severe diseases, pups stop nursing.
82
If you are cultivating rotavirus of mice in culture, what is required?
proteolytic enzymes to cleave the outer capsid proteins
83
How long does recovery from EDIM usually take?
two weeks
84
Is EDIM transmitted vertically?
no
85
What is histologically seen in the GIT with EDIM infection in pups?
hydropic change of the terminal villi with clubbing, edema of lamina propria, inflammation and necrosis of GIT is NOT COMMON
86
Will immune deficient mice of any age be affected by EDIM?
no, still only animals
87
Besides, GI lesions in EDIM affected mice, what other lesions can be seen that must be ddx'd from other viral infections?
thymic necrosis, ddx from mouse thymic virus
88
How is EDIM diagnosed?
serologically for screening, IHC or PCR for antigen.
89
What can cause false positives when testing feces of mice suspected of EDIM?
certain diets can interfere with fecal antigen ELISA tests leading to false positive.
90
which mice shed rotavirus persistently?
B cell deficient strains
91
Mouse Hepatitis Virus belongs to which viral family?
Corona virus
92
Which strains of MHV are the most commonly involved in natural infections?
Enterotropic
93
What antigens are used to distinguish various strains of MHV?
Spike (S) antigens
94
When are immune competent animals affected clinically by MHV?
95
When are immune deficient animals affected clinically by MHV?
any age. Athymic animals may have no clinical signs followed by wasting disease
96
What sites in the GIT are most commonly affected by Enterotropic MHV?
terminal ileum, cecum, colon
97
What is a hallmark lesion of MHV infection?
syncytia formation (some other viruses can still show syncytia)
98
How can dead pups from EDIM vs. MHV be differentiated?
EDIM animals likely have milk in the stomach, MHV animals often do not
99
Which biologics can go unidentified when having MHV infection?
B cells and hybridomas, may not have cytopathic effects (other viruses without cytopathic effects=Sendai, LCMV, Pneumonia virus of mice)
100
How does maternal immunity affect pup susceptibility to enterotropic MHV? polytropic?
ENTEROTROPIC: it's based on what immunoglobulins are IN THE LUMEN of the GIT. If pup not nursing (or weaned) then at risk for infection.
POLYTROPIC: IgG passed in utero or via suckling
101
Which mouse strains have shown high susceptibility or resistance to MHV?
DBA/2 highly susceptible and A/J resistant after weaning
102
How do enterotropic vs. polytropic strains of MHV differ?
Enterotropic targets GIT most often, but dissemination is possible. Polytropic strains infect respiratory tract then disseminate to brain and multiple organs. Most strains affect the liver.
103
How can MHV continue to be perpetuated in a colony of mice?
It is prone to mutations, bringing in naive animals, immunity to one strain does not confer immunity to another strain of the virus
104
What lesions are seen with enterotropic MHV on histology of the GIT?
syncytia of enterocytes, villus blunting. Classic picture in BB.
105
When and where are syncytia from MHV most easily detected?
infants, margins of liver lesions. lesion is transient in adults.
106
How is MHV detected in a colony?
serology very good for MHV, neutralization test to determine strains present.
107
Can MHV be propagated in culture?
Yes, research strains easily propagated but natural strains are more difficult. CMT-93 rectal carcinoma cells and mouse liver cells NCTC1469 can be used.
108
Animals that survive MHV infection often show what pathologic lesions?
hyperplasia in GIT, inflammation around vasculature in brain, focal lesions in liver
109
Which strains are susceptible to polytropic MHV infection? Resistant?
BALB/c, CBA, C3H/He, C3H/Rv
SJL=resistant to polytropic MHV
110
Recovery from enterotropic MHV requires what functional immune cells?
T cells
111
Mouse encephalomyelitis virus is part of what viral family? Enveloped or nonenveloped?
Picornavirus (in Cardiovirus family), nonenveloped
112
What is the target organ of Mouse Encephalomyelitis Virus for viral replication?
GIT
113
What determines clinical signs of Mouse Encephalomyelitis virus?
mouse strain and virus strain, similar to MHV in that there are multiple viral strains with varying levels of virulence.
114
Is vertical transmission present with encephalomyelitis virus infection?
no
115
How contagious is encephalomyelitis virus?
inefficiently transmitted, not very contagious
116
What clinical signs are seen with encephalomyelitis virus and when?
CNS signs are rare with infection, usually flaccid paralysis that prevents mice from accessing food and water.
117
Which mouse strains are susceptbile vs. resistant to encephalomyelitis virus?
Susceptible: immune deficient, SJL, DBA/2, C3H, SWR, PLJ
Resistant: BALB/c, B6, A, 129
118
What lesions are seen in the GIT vs. CNS with encephalomyelitis virus infection?
GIT - none even though this is initial site of replication
| CNS - demyelination, ventral horn affected most, meningitis, vasculitis, neuronal vacuolation
119
What tissues are best for identification of encephalomyelitis virus?
feces or mesenteric LN
120
What mouse viruses can be responsible for neurologic signs in mice?
Polytropic MHV, Paralytic syndrome in LDV with AKR/C58 strains, Polyoma virus induced tumors in athymic animals
121
What strain of mouse encephalomyelitis virus has been detected in rats?
MGH strain, high virulence
122
At what age is virus rarely found with encephalomyelitis infection in mice?
>6 months
123
HOw long can virus persist in the CNS after encephalomyelitis infection?
1yr or more
124
Mouse Norovirus is part of what viral family? enveloped or nonenveloped?
Calicivirus, nonenveloped
125
What is unique about mouse norovirus compared to other noroviruses?
it is the only one that can be grown invitro
126
What clinical signs are usually seen with mouse norovirus?
none except very specific transgenics
127
Which transgenics show lethality with mouse norovirus infection?
STAT1 null, Interferon alpha, beta, gamma null mice
128
What cell type does mouse norovirus replicate?
macrophages and dendritic cells
129
How is mouse norovirus controlled in a facility?
very difficult to eradicate since resistant to environmental decontamination. Depopulation, rederive, or cross foster neonates since they are resistant to infection. Test and cull not shown to be effective.
130
What lesions are seen in STAT1 null mice with norovirus infection?
alveolitis, pulmonary edema, coagulative necrosis of liver with minimal inflammation
131
Which mouse strains are reported to have mild diarrhea secondary to norovirus infection?
129 and C3H
132
Which mouse strains have shown persistent fecal shedding of 1-2 months?
RAG, SCID, B6, ICR
133
How is norovirus diagnosed?
serology, PCR or IHC for antigen in tissues/feces
