PMI covers the broad disciplines of microbiology and immunology. Research topics under these disciplines includes Autoimmunity, Basic immunological mechanisms, Bacteriology, Cancer immunology, Evolution, Host-pathogen interactions, Immunology of organ transplantation, Innate Immunity, Parasitology, Virology, Disease Pathogenesis, and Development of novel antimicrobial therapies. However many of these topics overlap to a significant degree. For example, what do infectious diseases, cancer, allergies, and autoimmunity have in common? They all result from imperfect functioning of the immune system. When the immune system reacts too weakly, infectious pathogens and mutated tumor cells can escape elimination and lead to life-threatening diseases. On the other hand, when the immune system reacts too strongly, responses to a benign substance such as pollen can cause allergies, and responses to body tissues can cause autoimmune diseases. The immune system also limits the success of organ transplantation, since the foreign organ is rejected by an especially vigorous immune response. The is a general consensus however, that the immune system evolved under pressure from the microbial world and studying pathogenesis is of critical importance to fully appreciating the immune system. Research directed at these areas can therefore have critical importance for many aspects of medical science and spans important model systems in genetics, physiology, and cellular biochemistry.