**Abstract**

Organ injury is mediated by dysregulated inflammatory response of the host to invading organism or antigen. Dysregulated immune response can be more than or less than what is required to contain the organism or antigen. All disease states converge on inflammatory damage to tissue irrespective of what triggers the initial insult such as a transplanted organ, microbe, autoimmunity, and even a malignancy. Injury immunity axis can be used to phenotype a disease state to explaining its etiology, treatment options and possible disease trajectory. It will address the core issue of inflammation at cellular level guiding clinicians to tailor the treatment on case to case basis. This chapter brings immunity to center-stage in diagnosis and management of diseases due to various causes. This can be accomplished by phenotyping diseases across injury immunity axis to ascertain the status of immune system forefront. It is indeed a novel concept by which we look at different manifestations of a disease through a unique perspective. It is also an attempt to acknowledge the fact that immune system work-up and immune biomarkers need better representation in the list of investigations. The importance of immunological basis of diseases needs significant amount of research and robust data to translate this knowledge into the standard of care.

**Keywords:** injury immunity axis, immune function tests, translational immunology, immune biomarkers, disease phenotyping
