Why doesnt the body fight back against HIV infection?
The body tries. Most patients have very high levels of circulating antibodies against HIV. However, these antibodies dont do much good because the virus is hidden inside cells where the antibodies cannot reach. What fails in HIV infection is a concerted attack of military cells (CTLs) against any cell harboring HIV. In order to have such a strong attack, the infected cells need to send a minimum of TWO signals to the military cells. One signal is appearance of foreign proteins on the surface of the invaded cell that are recognized by specific military cells to attack. The second signal is a specific chemical signal sent by means of certain specific chemicals some of which are called lymphokines. A protein generated by HIV called Nef has been shown to prevent a specific modification in the first signal AND interfere with several lymphokines required for the second signal. Thus, HIV blocks the signaling successfully and renders the military cells ineffective. This blocking or cloaking me
