The innate side of immunity
All animals - down to the fruit fly - possess a primitive system of defense against pathogens. This defense, called innate or natural immunity, is activated when microbial products trigger innate immune cells in a nonspecific manner. Two receptors in this system, called CD14 and Toll-like receptors (TLRs), are particularly important. These receptors are terrific at detecting bacteria, mycobacteria and fungi. Until now, scientists believed that CD14 and TLRs were involved in the recognition of these microbes only and that they could not recognize viruses.
In the November 2000 issue of Nature Immunology (Vol. 1, No. 5) scientists from Boston, Massachusetts, have discovered that CD14 and TLRs also function in antiviral responses. They examined the interaction of several respiratory syncytial virus (RSV) proteins with these receptors. These viruses cause a serious and common disease of the respiratory tract in infants and young children worldwide. One of the viral proteins was able to trigger the innate immune cells through TLRs and CD14 and also controlled the survival of this virus in mice. Understanding how the innate immune system helps control the virus will be important in the development of a vaccine. The discovery that RSV can alter the early, innate immune response brings this long-term goal a step closer.
University of Massachusetts Medical School
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(C) Nature Immunology press release.
Message posted by: Trevor M. D'Souza