Amsterdam, May 27th 2013-
Also this week MedZine brings you the latest medical news on various medical specialisms. In this editorial two striking studies are highlighted. The first describes the discovery of a sugar polymer found on the cell surface of several pathogens that is a promising target for a broad-spectrum vaccine. The second study reports on brain cells that were grown from skin cells of individuals with Down syndrome.
A broad-spectrum vaccine against a sugar polymer
One of the difficulties is fighting pathogens is that they differ very much in how they look at their surface to avoid being destroyed by the immune system. In a publication in Proceedings of the National Academy of Sciences a sugar polymer that is expressed on many different types of pathogen is identified. The sugar, known as beta-1-6-linked poly-N-acetyl glucosamine, or PNAG, is made by more bacterial, fungal, and other microbial organisms than previously thought including Streptococcus pneumonia (the cause of deadly pneumonias in the young and the elderly), Listeria monocytogenes (causing food poisoning), Neisseria meningitides (causing meningitis), and Candida albicans (a fungus). Humans and animals produce antibodies against this sugar but these don’t give complete protection. Therefore, the researchers created vaccine-induced antibodies that respond to a synthetic form of PNAG. These antibodies had the properties needed for killing microbes. Clinical trials are being conducted to test the effectiveness of antibodies against PNAG in one or multiple infectious diseases.
Growing Down syndrome neurons
Down syndrome is the most common genetic form of intellectual disability. It results from an extra copy of one chromosome. Although people with Down syndrome experience intellectual difficulties and other problems, scientists have had trouble identifying why that extra chromosome causes such widespread effects. In a study published in Proceedings of the National Academy of Sciences, Bhattacharyya and colleagues report on growing Down syndrome neurons derived from skin cells of patients. The skin cells were turned into pluripotent stem cells which were differentiated into neurons. They found that Down syndrome neurons had less synapses than healthy neurons. In addition, Down syndrome neurons were found to have an increased expression of genes that respond to oxidative stress. This could explain multiple symptoms of Down syndrome. These cells could be useful in identifying and testing new drugs against symptoms of Down syndrome.
Source: Eurekalert, and Proceedings of the National Academy of Sciences