AIDS-vaccines

Acquired immune deficiency syndrome (AIDS) was initially described in the USA in 1981, although sporadic cases probably occurred for at least two decades prior to this. By 1983, the causative agent, now termed human immunodeficiency virus (HIV), was identified. HIV is a 

The viral surface protein, gpl20, is capable of binding to a specific site on the CD4 molecule, found on the surface of susceptible cells (Table 10.17). Some CD4-negative (CD4 ) cells may (rarely) also become infected, indicating the existence of an entry mechanism independent of CD4. 

Infection of CD4+ cells commences via interaction between gpl20 and the CD4 glycoprotein, which effectively acts as the viral receptor. Entry of the virus into the cell, which appears to 

T-helper lymphocytes Blood monocytes Tissue macrophages 

Dendritic cells of skin and lymph nodes Brain microglia 

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J. Cohen, AIDS vaccines show promise after years of frustration, Science, 291, 1686 (2001). 

Wang X, Uto T, Akagi T et al (2008) Poly(y-glutamic Acid) nanoparticles as an efficient antigen delivery and adjuvant system potential for an anti-AIDS vaccine. J Med Virol 80 11-19... 

A number of approaches are being assessed with regard to developing an effective AIDS vaccine. No safe attenuated form of the virus has been recognized to date, nor is one likely to be developed in the foreseeable future. The high level of mutation associated with HIV would, in any case, heighten fears that spontaneous reversion of any such product to virulence would be possible. 

The single most important issue in developed countries is the safety of a vaccine, a single death in a million vaccinations for a new vaccine would be unacceptable (except possibly if it were an effective AIDS vaccine). While this is obviously important in a Third World country, other issues such as cost and how to deliver the vaccine are of paramount importance. 

Although the primary objective of any vaccine is its prophylactic use (i.e. prevention of future occurrence of a disease), AIDS vaccines may also be of therapeutic value. This supposition is based upon the fact that the immune system controls the viral infection for a time period. Hence, any agent capable of enhancing the anti-HIV immune response may prolong this elfect. 

The Project BioShield II Act of 2005, introduced to the U.S. Senate in April 2005, contains a proposal for so-called Transferable Intellectual Property Rights, in which a firm that developed a vaccine for a disease such as AIDS would obtain a wildcard patent extension that could be applied to a drug of its choice in the United States. The proposal has received the endorsement of the International AIDS Vaccine Initiative, which sees any proposal to increase research into AIDS vaccines positively. This is therefore a proposal that deserves serious scrutiny. 

Biel, P. 2001. Why is There No AIDS Vaccine World Economics 2 1-16. 

Cohen. J. "Aids Vaccine Research," Science, 1820 [December 17, 1993). 

Table 8.3 Some AIDS Vaccines Under Development...

Fienberg, M.B., and J.P. Moore. 2002. AIDS vaccine models Challenging challenge viruses. Nat Med 8 207. 

Robinson HL (2007) HIV/AIDS vaccines 2007. Clin Pharmacol Ther 82(6) 686-693 Roland KL, Cloninger C, Kochi SK, Thomas LJ, Tinge SA, Rouskey C, Killeen KP (2007) Construction and preclinical evaluation of recombinant Peru-15 expressing high levels of the cholera toxin B subunit as a vaccine against enterotoxigenic Escherichia coli. Vaccine 25(51) 8574-8584... 

Kiyono, H., Miller, C.J., Lu, Y., Lehner T. el al. (1995).The common mucosal immune system for the reproductive tract basic principles applied toward an AIDS vaccine. Adv. Drug Del. Rev., 18 23-51. 

Naylor PH, Sztein MB, Wada S, Maurer S, Holterman D, Kirkley JE, Naylor CW, Zook BC, Hitzelberg RA, Gibbs CJ, Jr. Preclinical and clinical studies on immu-nogenicity and safety of the HIV-1 pl7-based synthetic peptide AIDS vaccine— HGP-30-KLH. Int J Immunopharmacol 1991 13(Suppl 1) 117—27. 

Impediments, Imponderables and Alternatives in the Attempt to Develop an Effective Vaccine Against AIDS Vaccine 10 1053-1058, 1992... 

Edgington, S.M. (1992b). Is an AIDS vaccine possible Bio/Technology 10,768 771. 

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