CONCLUSION

The immune response to HIV in both the acute and chronic phases of infection is extraordinarily complex. HIV-specific immunity seems to play a significant role in controlling virus and perhaps slowing disease progression.

TABLE 12.1

Potential Mechanisms of HIV-mediated

CD4 impairment

Direct HIV cytotoxicity

HIV mediated syncytia formation

Cell-mediated cytotoxicity

CD8-mediated

NK cell ADDC

HIV-mediated CD4 dysfunction

Other:

Superantigen-mediated

Other autoimmune mechanisms

Anergy

as well as other viral infections. HIV is unique in that its target, the T helper cell, may play a critical role in the coordination of important virus-specific immune responses. The loss of this coordination probably results in impairment of both cellular and humoral immune responses, giving the virus an opportunity to replicate. This unchecked replication creates a cycle of viral replication, immune destruction, and further loss of immune control. A better understanding of the mechanisms employed by both host and virus will provide important insights into the pathogenesis of HIV infection and possibly stimulate future development of novel immune-based therapies and vaccines.

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