Published online Jan 14, 2016. doi: 10.3748/wjg.v22.i2.862
Peer-review started: March 11, 2015
First decision: April 13, 2015
Revised: May 16, 2015
Accepted: September 30, 2015
Article in press: September 30, 2015
Published online: January 14, 2016
Hepatitis C virus (HCV) infection is still a major public health problem worldwide since its first identification in 1989. At the start, HCV infection was post-transfusion viral infection, particularly in developing countries. Recently, due to iv drug abuse, HCV infection became number one health problem in well-developed countries as well. Following acute HCV infection, the innate immune response is triggered in the form of activated coordinated interaction of NK cells, dendritic cells and interferon α. The acquired immune response is then developed in the form of the antibody-mediated immune response (ABIR) and the cell-mediated immune response (CMIR). Both are responsible for clearance of HCV infection in about 15% of infected patients. However, HCV has several mechanisms to evade these antivirus immune reactions. The current review gives an overview of HCV structure, immune response and viral evasion mechanisms. It also evaluates the available preventive and therapeutic vaccines that induce innate, ABIR, CMIR. Moreover, this review highlights the progress in recent HCV vaccination studies either in preclinical or clinical phases. The unsatisfactory identification of HCV infection by the current screening system and the limitations of currently available treatments, including the ineligibility of some chronic HCV patients to such antiviral agents, mandate the development of an effective HCV vaccine.
Core tip: Hepatitis C virus (HCV) is a major global public health problem. Chronic HCV infection affected around 130-150 million of the world’s population. The current treatment is expensive, showed some restrictions and is not efficient for all patients. No licensed vaccine is available for clinical use, however, researches on developing a preventive and therapeutic safe vaccine, are evolving. This review gives an overview of HCV structure, immune response and viral evasion mechanisms. It also evaluates the available preventive and therapeutic vaccines that induce innate, antibody-mediated immune response, cell-mediated immune response and interferon, and highlights the progress in recent HCV vaccination studies either in preclinical or clinical phases.