Engineered cells seek out and kill HIV in living organisms

Although there is currently no cure for HIV, the body does already contain cells that fight the virus – the problem is, there just aren’t enough of them to completely get rid of it. In 2009, scientists at UCLA performed a proof-of-concept experiment, in which they were able to grow these CD8 cytotoxic T lymphocytes (better known as infection-fighting “T cells”) from genetically engineered human stem cells. Now, in a subsequent study, they have demonstrated that these engineered cells can seek out and kill HIV-infected cells in a living organism. In the previous project, the researchers took T cells from an HIV-infected individual, and isolated the T cell receptor within them – this is what allows the cells to identify and destroy cells infected with HIV. They proceeded to clone this receptor, then used it to genetically engineer human blood stem cells. These cells were then placed in human thymus tissue, that had itself been implanted in mice, where they proceeded to grow into HIV-specific T cells. While the study indicated that it was possible to create genetically engineered HIV-fighting cells in the body, it didn’t test how those cells fared against HIV in a living organism. The more recent study, however, did. This time around, similarly engineered HIV-specific T cells were introduced into infected “humanized mice” – lab mice that have been genetically engineered to carry human genes, cells or tissues. Two to six weeks later, tests were performed on the peripheral blood, plasma and organs of those mice. It was found that not only had the level of HIV in the bloodstream decreased, but the number of CD4 “helper” T cells had increased – CD4s are white blood cells that play a key role in fighting off infections, and they normally decrease in the event of HIV infection. According to the scientists, these results indicated that the introduced T cells had developed and migrated to the organs, where they fought the HIV infection. They did note, however, that even in humanized mice, HIV may mutate slower than it does in humans. This means that multiple T cell receptors might have to be used, to account for the higher likelihood of the virus mutating in humans. To that end, the researchers have now begun creating receptors that target specific parts of the HIV virus. "We believe that this study lays the groundwork for the potential use of this type of an approach in combating HIV infection in infected individuals, in hopes of eradicating the virus from the body," said lead investigator Scott G. Kitchen. A paper on the study was published yesterday in the journal PLoS Pathogens.

New technologies detect seizures, and could possibly even eliminate them

Seizures can be very scary experiences for people who suffer from them, especially since they may sometimes result in the need for medical attention. Unfortunately, they often come on so fast that the people getting them aren’t able to get out a call for help beforehand – they simply have to ride out the seizure on their own, and hope for the best. Now, however, two new technologies may be able to help. One is a watch that alerts caregivers when it detects movements associated with seizures, while the other is a system that could stop seizures before they start, by sending electrical impulses to the brain. A wearable alert device The watch, known as the SmartWatch, is made by California-based tech company SmartMonitor. It can be worn 24 hours a day, and detects repetitive, excessive arm motions outside of the user’s regular movement spectrum, associated with grand mal seizures. If they are able to, wearers can send out an alert to family members or other caregivers of their choice, simply by pressing a button on the watch. If not, within 15 to 30 seconds the watch will automatically send a Bluetooth signal to the user’s Android smartphone (which can’t be any farther than five feet away), which will in turn send that same alert to the same people. False alarms can be cancelled with the press of a button. Afterwards, a secure record of the time, duration and geographical location of seizures can be accessed by the user, for possible onward use by health care professionals. The SmartWatch is available in the U.S. as of today – the price has not yet been made public. A system to stop seizures At Baltimore’s Johns Hopkins University, meanwhile, assistant professor of biomedical engineering Sridevi V. Sarma is leading research into software that could more efficiently stop seizures before they happen. Currently, when people are prone to seizures that don’t respond to drug treatment, they sometimes have electrodes surgically implanted in their brains. Algorithms running in an accompanying electronics package monitor the brain’s electrical activity, and cause the electrodes to administer a electrical pulse to the brain, when seizure-like activity is detected. While this setup is often effective at stopping the seizure from proceeding, it is also very prone to false alarms. “They’re very good at detecting when a seizure is about to happen, but they also produce lots of false positives, sometimes hundreds in one day,” Sarma said of these systems. “If you introduce electric current to the brain too often, we don’t know what the health impacts might be. Also, too many false alarms can shorten the life of the battery that powers the device, which must be replaced surgically.”

Sarma and her team addressed this problem by analyzing the brain electrical activity of epilepsy patients, recorded before, during and after seizures. Specifically, they wanted to get a better idea of what sort of activity immediately preceded seizures. Once that activity was identified, they then trained their software to act only on it, while ignoring other types of activity that can confuse traditional systems. When tested on recordings of the brain activity of four epilepsy patients, the system easily detected all of the actual seizures, but produced up to 80 percent less false alarms than conventional technology. Sarma now plans on fine-tuning her software, using brain recordings from a further 100 patients. She hopes that within two to four years, it could be integrated into brain implants that could be used in clinical trials. More information on both the SmartWatch and the Johns Hopkins software is available in the videos below.