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Summary
There is substantial evidence from studies of natural processes that immune competence plays a major part in determining the outcome of anogenital human papillomavirus (HPV) infection. Prevention of infection would appear to be antibody mediated and papillomavirus genotype specific. Natural infection is slow to produce an appropriate therapeutic response to viral proteins, probably because HPV has adopted several strategies to prevent effective presentation of viral antigens to the immune system. Optimal therapeutic strategies for anogenital HPV infection would therefore appear to involve the induction of a strong virus-specific cell-mediated immune response, either by inducing local inflammation and cytokine production or by immuni-sation with appropriate antigens.
Introduction
Papillomavirus, like many other viruses, is amenable to attack and clearance by the immune system. However current treatments ignore the virus and concentrate instead on the lesion, which is 'burnt', 'poisoned', 'frozen', 'fried' or 'cut' using a range of physical treatments. In many ways prevailing treatment is analogous to treating genital herpes with a flame-thrower! The obvious solution is to treat genital warts as a viral infection, and use anti-viral treatments specifically designed to rid the body of this virus and induce long-lasting immunity.
The potential for anti-viral treatment suggests two key questions: (1) is there a natural immune response to papillomavirus infection? (2) if there is a response, can it be improved?
In answer to the first question, there is undoubtedly an immune response, but it is weak and comes latehence the difficulty in managing this infection. It follows that stimulation of an appropriate immune response may improve management of human papillomavirus (HPV) infections by `helping nature'.
A major barrier to development of new treatments is that until relatively recently it has not been possible to culture the human papillomavirus. This changed with the discovery that `virus like particles' could be manufactured in the laboratory using recombinant DNA technology. The particles appear identical to the real virus, both on electron microscopy and immunologically. The development of these particles has enabled a detailed exploration of the immunology of HPV infection.
In one study Carter et al. (1996) recruited a group of female college entrants with no prior exposure to papillomavirus-all were HPV-negative. During regular follow-ups throughout their college career, several acquired infection. Viral acquisition was followed...