Understanding Hepatitis

Efforts to manipulate the genetic structure of the hepatitis viruses with the goal of preventing their reproduction have met with limited but encouraging success. One type of investigation binds complementary (“antisense”) nucleotides to portions of the viral genes. Antisense nucleotides are those that bind to a target gene and prevent a function because it cannot be interpreted by the metabolic processes of the virus, which cannot then reproduce. Such disabled viruses might be useful in inducing neutralizing (protective) antibodies. If we can discover a way to bind such antisense segments to the genes of virus infecting an individual, the disease can be cured. Much more of this research must be done before it can be applied to humans.

One of the essential steps in infection of cells by any virus is attachment to specific receptors on the liver cell surface followed by entry into the cell (see chapter 1). If these receptors can be thoroughly characterized, it is possible that innocuous compounds can be formulated which occupy them, therefore making them unavailable to the virus. Research in this area continues but is not close to being available for human application.

Few research efforts are being made to develop additional vaccines against hepatitis A and B, because those we have are so effective. Presently available vaccines against HAV are 98 to 100 percent effective in inducing protective antibodies against the disease. While it is possible to virtually eliminate

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