New Discovery about Antibodies
This finding transforms the previous scientific understanding of immunity to viral diseases and gives scientists a different set of rules that pave the way to the next generation of antiviral drugs.
Previously scientists believed that antibodies could only reduce infection by attacking viruses outside cells and also by blocking their entry into cells. Scientists at the MRC Laboratory of Molecular Biology in Cambridge have now shown that antibodies remain attached when viruses enter healthy cells. Once inside, the antibodies trigger a response, led by a protein called TRIM21, which pulls the virus into a disposal system used by the cell to get rid of unwanted material. This process happens quickly, usually before most viruses have chance to harm the cell. The MRC scientists have further shown that increasing the amount of TRIM21 protein in cells makes this process even more effective, suggesting new ways of making better antiviral drugs.
Commenting on the possible effects for veterinary medicine, Duncan Maskell from the Department of Veterinary Medicine at the University of Cambridge said: "This discovery was made in mouse cells, and the scientists have then compared this system between different animal species, including humans, other primates and dogs, seeing a remarkable degree of conservation. There is every reason to assume that this system is present in all mammals, and possibly even in non-mammalian animals. This indicates very strongly that any improvements in therapies that result from understanding this system will be directly applicable to a very wide range of veterinary infectious diseases in a very wide range of animal species."
Dr Leo James from the MRC Laboratory of Molecular Biology (LMB) and lead author of the study, said: “Doctors have plenty of antibiotics to fight bacterial infections but few antiviral drugs. Although these are early days, and we don’t yet know whether all viruses are cleared by this mechanism, we are excited that our discoveries may open multiple avenues for developing new antiviral drugs.”
Sir Greg Winter, deputy director of the MRC Laboratory of Molecular Biology, added: “Antibodies are formidable molecular war machines; it now appears that they can continue to attack viruses within cells. This research is not only a leap in our understanding of how and where antibodies work, but more generally in our understanding of immunity and infection.”
Veterinary practices are being urged to help owners safely dispose of any unused and expired pet medicines - not just antibiotics - during November's Animal Medicines Amnesty. 
