IgM, not IgG, a key for HIV vaccine

Although HIV infections induce a very strong humoral immune reaction with various neutralization activities and a well-defined cellular immunity, HIV vaccine development based on traditional approaches failed. The fact that neither specific antibodies nor activated CD8+ cytotoxicity T-cells could provide primary protection in high risk populations raises the question concerning whether a specific vaccine is feasible. While the immune system as an intact defense system against HIV is ineffective or may even enhance the virus spread, a distinct small part of the system plays important role in delaying the progress of the disease. After carefully dissecting the different immune reactions against the virus, a new HIV vaccine strategy is indicated.