What is an antigen variation?

Antigenic variations is a shift in surface antigens on an infectious organism that helps the body to avoid immune systems of potential hosts. Organisms use various tactics to change the composition of antigens on their surface. This evolutionary trick allows them to continue to grow and spread in populations and maintain their existence. Scientists are interested in how it works because it can play a role in how people become a re -disease. The antigen variations are also interesting for people who are in charge of the development of vaccines and drugs to prevent and treat infection. When the body first enters the host, the immune system does not recognize any of the proteins and can allow the body to multiply and create infection. The immune system learns that these proteins are dangerous, and when the organisms are occurring, the body will go to the attack. He sees proteins, recognizes them as a threat and sends immune cells to kill the body.

Without antigenic variations, infectious organisms would quickly extract. The number of vulnerable people in the population would drop and organisms would not be able to survive. However, if the organism can change proteins in future generations, it can re -adapt and start adjusting the immune system. This can happen among hosts, but it can also happen during active infection. People often notice cyclic patterns in infections where they begin to improve, are much worse and then improve again. This is the result of an antigen variation in several generations of organisms growing inside the body.

Some organisms experience random mutations that can occur at any time. Others actually program in antigen variations. These organisms have proteins such as cognitive signs on one of James Bond; They can switch the proteins on and off and introduce a completely different board number, as it was, the immune system. As they pass through different surface antigens, some hostsThey can resist them because they have been exposed in the past, but others will be susceptible to infection.

Antigen variations can occur through recombrication, inversion, deletion and other DNA tricks. Some organisms are better than others. Influenza viruses are a notorious example; They change so much that people have to design a new vaccine every year to vaccinate people against the flu. Likewise, the HIV virus mutates very quickly and randomly, making prevention or treatment more difficult because it is a moving target.