How does the immune system response to HPV?

During the early stages of human papillomavirus (HPV) infections, the innate immune system creates a pro-inflammatory microenvironment by recruiting innate immune cells to eliminate the infected cells, initiating an effective acquired immune response.

Can immune system fight HPV?

Most people who become infected with HPV do not know they have it. Usually, the body’s immune system gets rid of the HPV infection naturally within two years. This is true of both oncogenic and non-oncogenic HPV types.

How does HPV affect the cell cycle?

HPV infects dividing basal epithelial cells where its dsDNA episomal genome enters the nuclei. Upon basal cell division, an infected daughter cell begins the process of keratinocyte differentiation that triggers a tightly orchestrated pattern of viral gene expression to accomplish a productive infection.

What is the pathophysiology behind HPV?

The productive life cycle of HPVs is linked to epithelial differentiation. Papillomaviruses are thought to infect cells in the basal layer of stratified epithelia and establish their genomes as multicopy nuclear episomes. In these cells, viral DNA is replicated along with cellular chromosomes.

What are the virulence factors of HPV?

The virulence of HPV is mainly exhibited by E5, E6 and E7 encoded oncoproteins that cause low to high-grade cervical lesions (CIN-1, 2, 3), leading to form 99.7% of squamous cell and 89% of adenocarcinomas cervical cancer worldwide.

What happens if your immune system doesn’t get rid of HPV?

But for some people, the immune system does not get rid of the infection. We do not know exactly why that is. If the virus stays in the body for longer, it may cause damage to cells. Over a long time, these abnormal cell changes may develop into cancer.

How does HPV affect cervical cells?

HPV infects the squamous cells that line the inner surfaces of these organs. For this reason, most HPV-related cancers are a type of cancer called squamous cell carcinoma. Some cervical cancers come from HPV infection of gland cells in the cervix and are called adenocarcinomas.

How are cells infected with HPV?

Host cell entry of HPV is initiated by binding of the virus particle to cell surface receptors (Figure ​ 1). It has been suggested that virions bind initially to the basement membrane prior to transfer to the basal keratinocyte cell surface [18].

How is HPV activated?

You can get HPV by having vaginal, anal, or oral sex with someone who has the virus. It is most commonly spread during vaginal or anal sex. It also spreads through close skin-to-skin touching during sex. A person with HPV can pass the infection to someone even when they have no signs or symptoms.

Why is HPV persistent?

Most cases of HPV infection tend to be cleared by the immune system without intervention 1–2 years post-exposure; it is thought that persistent infection is most likely due to a lack of HPV-specific T-cell immunity [74].