March 4, 2008 (Bronx, NY) By outfitting immune-system killer cells with a new pair of genes, scientists at the Albert Einstein College of Medicine of Yeshiva University transformed them into potent weapons that destroy cells infected with HIV, the virus that causes AIDS. Their novel strategy of genetically engineering immune cells to redirect their infection-fighting ability toward killing HIV-infected cells could lead to an entirely new approach for combating AIDS and other viral diseases. The findings appear in the March issue of the Journal of Virology.
After someone is infected with HIV, a subgroup of their immune cells known as CD8 cytotoxic T lymphocytes, or CTLs, recognize cells infected with HIV and kill them before they become HIV-producing factories. This CTL activity initially keeps the infection in check.
But thenlargely because these CTLs may not bind tightly enough to the infected cells or because HIV mutates so rapidlythe virus typically evades and ultimately overpowers the immune system, leading to an increase in viral load that, in the absence of drug therapy, results in AIDS. However, a very small percentage of HIV-infected people known as elite controllers manage to suppress HIV infection for many years.
Certain of the CTLs of elite controllers may be genetically equipped to bind tightly to HIV-infected cells and destroy them and thereby suppress the infection indefinitely, says Dr. Harris Goldstein, senior author of the study and Director of the Einstein/Montefiore Center for AIDS Research. Our idea, says Dr. Goldstein, was first to identify the elite controllers super CTLs and to isolate the genes that enable these cells to bind tightly to HIV-infected cells and kill them efficiently; then we would transfer these genes into CTLs that do not recognize HIV-infected cells and convert them into potent killers of those cells.
After infecting a cell, HIV instructs it to make viral proteins. Tiny bits of these proteins
|Contact: Karen Gardner|
Albert Einstein College of Medicine