Kaposi Sarcoma Associated Herpesvirus (KSHV), also known as Human Herpesvirus 8 (HHV-8), is a member of the Herpesviridae family and the causative agent of Kaposi sarcoma, a type of cancer that affects the skin and other organs.
KSHV is an enveloped double-stranded DNA virus that primarily infects human endothelial cells, which line the blood and lymphatic vessels, and also affects certain immune cells. It is transmitted through various routes, including sexual contact, blood transfusions, and organ transplantation. KSHV is more common in individuals with weakened immune systems, such as those living with HIV/AIDS.
Upon infection, KSHV establishes a persistent lifelong infection in the host, residing in a latent state within the infected cells. During latent infection, the viral DNA is maintained within the host genome and only a limited number of viral genes are expressed. However, in certain circumstances, such as impaired immune responses, the virus can reactivate and enter a lytic phase, where viral replication and full gene expression occur, leading to the production of new infectious viral particles.
The hallmark of KSHV infection is the development of Kaposi sarcoma tumors. These tumors typically manifest as red or purple patches, nodules, or plaques on the skin, but can also affect internal organs such as the lungs, liver, and digestive tract. Additionally, KSHV is associated with other conditions, including primary effusion lymphoma and multicentric Castleman disease.
Understanding the biology and pathogenesis of KSHV is crucial for the development of targeted therapies and prevention strategies to combat the associated diseases.
