Samuel K Campos

Research Interests

Samuel Campos, PhD, studies early events of Human Papillomavirus (HPV) infection. HPVs are small, non-enveloped DNA viruses that cause a variety of lesions ranging from benign waters to cervical cancers. Although over 100 types of HPVs have been identified, HPV16 is the most prevalent, and is alone responsible for more than 50% of cervical cancers in women worldwide. Dr. Campos and his lab study the mechanisms of HPV virus transmission at a cellular level, in hopes to discover new approaches for the prevention and treatment of HPV.HPV16 virions consist of an ~8kb circular dsDNA genome packaged into a ~60 nm protein capsid. The genome is condensed with cellular histones and exists in a chromatin-like state. The capsid is comprised of 72 pentamers of the major capsid protein L1 and up to 72 molecules of the minor capsid protein L2, localized along the inner capsid surface, within the central cavities beneath the L1 pentamers. Mature HPV16 virions exist in an oxidized state, with adjacent L1 pentamers crosslinked together by disulfide bonds to stabilize the capsid. In order to establish an infection, HPV16 virions must bind and penetrate host cells, ultimately delivering their genomes to the host cell nucleus to initiate early gene expression, cell cycle progression, and genome replication. Non-enveloped viruses are faced with the challenge of getting their genetic material across a cellular membrane and often overcome this by disrupting the endosomal or lysosomal membranes and translocating to the cellular cytoplasm during the course of intracellular virion trafficking.