Engineered Stem Cells Seek out and Kill HIV in Living Mice

A team of researchers at UCLA, led by Scott G. Kitchen, who is an assistant professor of medicine in the division of hematology and oncology at the David Geffen School of Medicine at UCLA, have demonstrated that human stem cells that have been genetically altered into HIV-fighting cells can actually be used in living organisms to attack HIV-infected cells.  The research team at UCLA, knowing that CD8 cytotoxic T lymphocytes of the “killer” T cells are able to destroy the HIV-infected cells but are not sufficient enough in numbers to destroy all of the HIV-infect cells to clear the body, have discovered a way to clone the receptor cells which has allowed them to genetically engineer human blood stem cells.  They made this discovery by implanting human thymus tissue, which they have injected with the human stem cells, into mice.  This allowed the research team to study the reaction that the human stem cells had inside of a living organism.  They discovered that the human stem cells developed into HIV-specific CD8 cells that could attack the cells that contained the HIV proteins, but in doing so realized that the T cell receptors need to be matched to an individual.  The mice were tested two and six weeks after being introduced to the engineered human stem cells and concluded that the steam cells were capable of developing and fighting the infections.  The research showed that during these tests the CD4 “helper” T cells had increased and the HIV infected cells had decreased.  They concluded with a potential weakness that HIV- infected cells may be less likely to attack mice cells as quickly as humans so this could be one way to account for a possibly higher mutation rate of the HIV cells in humans.This is still a great first step in correcting the defects of the human T cell with regards to HIV infected humans.