Historical development and background. Immunology; theory and practice. Oncogeny of the immune system. Phytogenetic development of immune system in vertebrates and invertebrates, primary and secondary lyrnphoid organs, homing of lymphocytes, phagocytes, immunoglobulins, chemokines, interleukins, lymphokines, innate immunity, acquired immunity, complement system, immunogens, haptens, antigens, adjuvants, mitogens, antigen presenting cells, immunization, immune control of disease-infections/tumours, transplant and organ rejection, graft versus host reaction. Establishment of infection, route and interaction with epithelial surfaces, stages of infection and resistance to epithelial infection.