|MadSci Network: Immunology|
There are several reasons why AIDS patients deteriorate even though they have antibodies to HIV. 1. An individual can make many different antibodies to different components of the virus. The most important antibodies are those that neutralize the virus, preventing its entry into other uninfected cells. Because of the way it replicates, HIV can rapidly mutate to escape neutralization by these antibodies. 2. With AIDS there is a progressive decline in T lymphocytes, which are needed for all aspects of an immune response, including production of antibodies to new variants of HIV. 3. Once it gets inside a cell, the virus is safe from any direct attack by antibodies.
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