#14 Lymphotropic Herpes Flashcards
Characteristics of Lymphotropic HSVs
- Replication and latency in cells including_____ origin
- Persistantant infection is balance btwn _______
lymhoid
lytic and latent
γHSV—oncogenic:
EBV (HHV-4) and Kaposi’s Sarcoma Virks (HHV-8)
EBV (HHV-4) and Kaposi’s Sarcoma Virks (HHV-8) are latent in
Latent in B cells and Plasma cells
Human herpes- 6b
HHV-6b
Latent in
T lymphocyte
CMV or Cytomegalovirus what type of herpesvirus
β Herpes virus:
- Infected Cells
a. get very big, have inclusion bodies and characteristic OWLS eyes
CMV
- Disease referred to as what for CMV
Cytomegalic inclusion body disease, CMV disease, Inclusion body disease
HHV-5 (beta) is what herpes viurs
CMV, dsDNA, icosahedral
Transmission of CMV
secretions-semen, cervix, blood, saliva, tears, breast milk, urine and feces, blood transfusion, organ transplant, and transplacental transmission
CMV presentation in healthy adults
Asymptomatic in health adults: see mild mononucleosis or cold-like symptoms
What is the leading cause of congential birth defects?
CMV (HHV5) beta HSV
a. mild to severe mental retardation, deaf, death b. TORCH: it’s the ‘C” and is an acroynm for viruses that cause congenital birt defects
If you get CMV and are immunocompromised, what do we see?
- Symptomatic upon immunosuppresion
a. Chemo/organ transplant/HIV
CMV persistant infection we see
atherosclerosis/ immunosenescenes/ neuroblastoma
Stages of gene expression for CMV
how many genes does it express?
Stages of gene expression: immediate/early/ and late
—-. expresses over 750 proteins~ that’s a TON!
CMV Encodes own _______ machinery
DNA repliation
thats why it so fucking huge
CMV LYTIC Replication cycle
Binding/penetration happens withing ____ mins and we can see membrane fusion or endocytosis in the _______
30 mins
epithelial cell
Once CMV Enters into cytoplasm
a. Sends tegument protein ______ to nucleus for transcrtiption
pp65
What is the purpose of pp65 in CMV?
its a tegument protein CMV sends to nucleus for transcription
- Transcription if CMV occurs in: ______
a. immediate early transcrtipion of DNA→ early transcription→ late transcription
nucleus
For CMV:
DNA replication:
Encapsidation at :
Envelopment/release will take:
1-2 days
2-3 days
72-96 hours
Lytic CMV infected Cell
1. infected cell the nucleus is HUGE because
a. virus in making TOS of viral DNA
What ‘s special about the nucleus during the lytic cycle in CMV
See the nucleus bent arount the replicaiton cytosole
Transmission of CMV
- Direct contact w/ virus containg secreations: semen/cervicle/blood/saliva/tears/breast milk/urine/poo
~ Inoculation onto mucosal site
- Other routes not as common for CMV
blood transfussion, organ tranplants/ transplacental transmission
For CMV, shedding can occur:
viral excreation starts at 1 month and shedding can contineu for months to >1 yrs
with or without symptoms
Highest rate of incidents and transmission for CMV
trasmission via daycares~~~ big population in children under 18 monts
CMV dissemination
CMV dissemination
1. Cell associated—poorly released from infected cell 2. Slow replication cycles 3. Lytic replication; occurs EVERYWHERE 4. Laten infectin: more in CD34+ hematopietic progenitor cells and monocytes 5. Frequency of reactivation: 1 in 10,000 of infected monocytes~ not a ton, but enough
Where does lytic replicaiton occur for CMV
everywhere
Location for latent infection of CMV
more in CD34+ hematopietic progenitor cells and monocytes
Innate immune response to CMV
Macrophage, INF and NK cells control but are insufficient to clear virus
- Humoral response to CMV:
no role, but may limit re-infection.
a. involves neutralizint antiBs directed agains surface antigens such as gB, gH, pp65, pUL-128
- Cell mediated immune response to CMV:
keey CTLs will kill CMV infected cells
a. up to 10% of all CD8 T cells in body are directed against CMV (huge %!!!) b. cytotoxic T cells are main players in fight CMV
main players to fight CMV
cytotoxit T cells
can host immune reponse completely take care of CMV
- Immune response can’t completely control CMV
Reinfection by different CMV variants occurs: high degree of intra-host genomic variability