Immunology concerns with multifaceted aspects that revolve around the clinical challenges of the defense of the host, several mechanisms involved in the fight for survival, tumor immunology, allergic reactions, transplantations and auto-immunity.
Golub and Green (1991) defined immunology as the “science of self/non-self discrimination”. This definition, although small, focuses on how important is the concept of self. In addition to defensive and restorative processes, the immune system engages itself in information processing and cognition, active interaction with the environment for maintaining the equilibrium and for symbiotic relationship, so essential for living in this prodigious universe. This gives rise to two orientations: 1. The biological system concerning the insularity of the organism and immunity for the sake of protection. 2. The ecological context concerning the organism’s dynamic entity while interacting with the environment at large.
In short, the field of immunology is related to organism as a whole, biological identity, individuality of the organism and several physiological processes utilized in a continual effort to maintain the homeostasis on the face of variable situations.