L10 Human Papilloma Virus
Explain the morphology of papova viruses
They are non-enveloped viruses that have an icosahedral, nucleocapsid, supercoiled DS circular DNA
Figure 1: Icosahedral structure
What are the two types of papova virus?
a. Papillomaviruses
b. Polyomaviruses
Describe papillomaviruses:
They are viruses that induce hyperplastic epithelial lesions in their host. They exhibit tissue and cell
specificity, hence why they only infect epithelial surfaces and mucosal membranes.
There are 100 types of HPV that have been recognized, and 73 genotypes identified. Each genotype is
associated with a specific clinical entity.
Like they family that they originate from, HPV ae also unenveloped “naked” DNA viruses.
Not grown on culture.
Replication takes place in nucleus
The virus is produced from skin warts while complete virions ae not released from malignant lesions.
What does the ds-genome of HPV encode for?
- 7 early regulatory polypeptides (E1-E7)
- 2 late structural proteins (L1-L2)
Viral DNA replication and expression of late proteins are restricted to differentiating cells.
What is the role of the 7 regulatory proteins?
E1 & E2 are DNA binding proteins involved in regulating viral transcription and replication
E6 & E7 change the activity of cell regulatory proteins that govern the admission into, as well as the
speed, cell division cycle, and differentiation pathways.
What are the types of lesions that lead to malignancies?
a. Lesions with high risk of progression into malignancy
Cervical Carcinoma
Explain the morphology of papova viruses
They are non-enveloped viruses that have an icosahedral, nucleocapsid, supercoiled DS circular DNA
Figure 1: Icosahedral structure
What are the two types of papova virus?
a. Papillomaviruses
b. Polyomaviruses
Describe papillomaviruses:
They are viruses that induce hyperplastic epithelial lesions in their host. They exhibit tissue and cell
specificity, hence why they only infect epithelial surfaces and mucosal membranes.
There are 100 types of HPV that have been recognized, and 73 genotypes identified. Each genotype is
associated with a specific clinical entity.
Like they family that they originate from, HPV ae also unenveloped “naked” DNA viruses.
Not grown on culture.
Replication takes place in nucleus
The virus is produced from skin warts while complete virions ae not released from malignant lesions.
What does the ds-genome of HPV encode for?
- 7 early regulatory polypeptides (E1-E7)
- 2 late structural proteins (L1-L2)
Viral DNA replication and expression of late proteins are restricted to differentiating cells.
What is the role of the 7 regulatory proteins?
E1 & E2 are DNA binding proteins involved in regulating viral transcription and replication
E6 & E7 change the activity of cell regulatory proteins that govern the admission into, as well as the
speed, cell division cycle, and differentiation pathways.
What are the types of lesions that lead to malignancies?
a. Lesions with high risk of progression into malignancy
Cervical Carcinoma
