Background Information

      Immunology is the study of the immune system. Our immune system acts as a defense mechanism by protecting us from foreign organisms such as bacteria, viruses, parasites and fungi which may enter our body through different openings. Just like humans, other organisms like plants, and even human pathogens, such as parasites, also have immune systems. Although there may be similarities between the immune systems of different organisms, the molecules, the cells, the pathogens that can infect the organism and the type of immune responses mounted towards them may also differ. 

      The immune system carries out two different types of immune responses: the innate immune response and the adaptive immune response. The innate immune response is the first line of defense as it acts without the recognition of specific species of a type of invader. For example, if a bacteria has invaded the body, the innate immune response will recognize that it is a bacteria and not necessarily the species of the bacteria (e.g. Campylobacter jejuni). The adaptive immune response is responsible for specific clearance of invading organisms. Each type of immune response has its own set of cells, molecules and tissues.

       We are not the only ones with an immune system. Each species needs to defend themselves against foreign invaders. Therefore, they also have an immune system. There may be similarities or differences between the immune systems which we will explore through this project. 

       The tree of life or the phylogenetic tree is a diagram that shows the evolutionary relationship between the organisms by comparing different characteristics of each of them. In our project, we use the phylogenetic tree to depict the evolutionary relationship between different species by comparing the immune systems.