Ischemia Reperfusion Injury (IRI) is a mechanism that can lead to trombo inflammation and tissue injury in connection to several clinical states and diseases. IRI can arise in connection to:
- Organ transplants
- Heart surgery
- Heart attack
IRI is the damage that occurs to the transplanted organ when blood circulation is returned to the organ following a period of ischemia, ie lack of oxygen. IRI will always impact organs in connection to a transplant. When the organ (for instance kidney, liver, heart) is removed from the doner, the organ is stored at a temperature of +4oC. When the innate immune system comes into contact with cells that have been damaged by a lack of oxygen, the immune system identifies the cell as unknown and consequently attacks the cell, and this leads to a trombo inflammation. By preventing inflammation, the quality of the organ will increase and thereby leads to a better health outcome of the transplant.
Endothelial cells, which coats the organ, are normally covered with glycocalyx (GC) which acts as a defence against attacks from the immune system. The GC protection is partly mechanical but is related to the GC-bound regulators of IIIS-components, e.g. ATIII, C1INH, factor H, C4BP. Due to ischemia, the GC of the cells is fragmented, leading to that the protection against the attacks from the immune system is lost.