Substantial progress has been made in the area of stem cells. Despite the Bush Administration’s 8 1/2 year ban on federal funding for embryonic stem cell research, and President Obama’s recent reversal, adult stem cell therapies have been making progress in terms of clinical implementation. This may be related to the safety concerns of embryonic stem cells, which have included differentiation into undesired tissues, as well as cancer. In contrast, adult stem cells have been used for more than 4 decades in the area of bone marrow transplantation and for over a decade in other areas. Primarily, non-bone marrow transplant studies have been focused in the area of heart failure, however smaller studies have investigated the use of stem cells in liver and kidney failure.
The field of stem cell therapies has recently been expanded. In a study published December 7in the medical journalPloS ONE, scientists from the University of California Los Angeles reported that human blood cells derived from adult stem cells can be engineered into cells that can target and kill HIV-infected cells – a process that could potentially be used against a range of chronic viral diseases.
The leader of the study, Dr. Scott G. Kitchen, Assistant Professor of Medicine in the Division of Hematology and Oncology at the David Geffen School of Medicine at UCLA and a Member of the UCLA AIDS Institute stated "We have demonstrated in this proof-of-principle study that this type of approach can be used to engineer the human immune system, particularly the T-cell response, to specifically target HIV-infected cells," Additionally, he commented on the possibility of future studies. "These studies lay the foundation for further therapeutic development that involves restoring damaged or defective immune responses toward a variety of viruses that cause chronic disease, or even different types of tumors."
Possible methods of manipulating blood cells to make them resistant to HIV infection includes genetically altering proteins called receptors. T cells have a specific receptor called CXCR5 which when mutated cannot be infected with HIV. Certain subsets of the human population who are resistant to HIV have this mutation in CXCR5, but also have normal T cell activities. One of the possible genetic alterations that can be performed in patients with HIV is to induce a similar CXCR5 mutation to endow resistance. Stem cell types that could be used include bone marrow, cord blood, or expanded peripheral blood stem cells.
