Immunology is a branch of biomedical science that covers all aspects of the immune system. It is important in maintaining our healthy physiological states as well as keeping our bodies out of trouble. Recent advances in technology have helped further our understanding of the intricacies of the complex system and mechanisms at play to keep us in check on a daily basis. This year, contributions by three professors in the field of immunology have been recognized by a Nobel Prize for Medicine. Current research has shed light on the possible use of injecting donor liver cells for the replacement of liver function, and methods in combating HIV.
The 2011 Nobel Prize for Medicine was awarded to three professors: Bruce Beutler, Jules Hoffmann, and Ralph Steinman. Their work relating to the immune system has led to break- throughs in our understanding of the pathophysiology of infections and chronic diseases, as well as the foundation for developing vaccines against tumours. Beutler and Hoffmann both received their share of the Nobel Prize for their discoveries concerning the activation of the innate immune system . The innate system is the first of the two lines of immune defences, providing an immediate and non-specific response to an antigen . Hoffmann discovered the role of Toll genes in Drosophilia where mutations of the Toll gene is correlated with a predisposition to in- fections and increased mortality . His work has led to the discovery of 10 Toll-Like Receptors (TLR) in humans and their role in the pathogenesis of diseases. Beutler discovered that TLR4 binds to lipopolysaccharide (LPS) released by gram-negative bacteria . This binding is responsible for the initiation of the inflammatory response in humans. It is now known that mutations and variants of TLRs predispose to infection and chronic inflammatory conditions.
Steinman coined the term dendritic cells in 1973. Dendritic cells are involved in the acquired immune system , and are believed to link the innate and acquired immune responses as well as function to present antigens to T helper cells. Dendritic cells provide a memory function to allow a quicker re- sponse to future infections. Applications of research done has led to the creation of vaccines to treat glioblastoma multiforme (GBM), most common malignant brain tumour in adults . The vaccine consists of dendritic cell immunotherapy that induces a T cell response to specific antigens present on the surface of the gliomas. Evidence has shown an increased mean survival rate in these patients as phase II studies show promising results.
Recent developments in immunology have led to an alternative to in organ transplantation. Iyaad Syed, a 9-month old infant who suffered from viral hepatitis was put on a donors list. Instead of a liver transplant, he received injections of donor liver cells as part of a new trial involving injections of coated liver cells into the abdomen . The injection is advantageous as it doesn’t require immunosuppressants following treatment. Under the new technique, Iyad successfully recovered. This breakthrough may mean that injections of donor liver cells may replace transplants in the future. This is especially important in the face of increasing numbers of patients waiting for a liver transplant since a vast majority are left untreated due to a shortage of donors.
Recent studies on HIV by scientists in France and the United States have revealed a possible mechanism to stop the proliferation of the human immunodeficiency virus for the treatment of the disease . Studies have shown that the protein, SAMHD1, can prevent HIV from replicating in myeloid cells, a group of white blood cells commonly infected during the disease. SAMHD1 degrades deoxynucleotides, the building blocks for the formation of the virus in these cells. This new method in stopping the progression of HIV may see the development of new antivirals. Since, HIV is one of the most common chronic infectious diseases in the world, the implications on global health is enormous.
Developments in immunology have strong implications for medicine. Recent breakthroughs are already in use to improve the lives of patients, increasing our understanding of the immunological mechanisms present in both healthy and diseased states.
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