Article type:
Resource
Estimated read time:
3 mins min read
Published:
16/09/2025
Inflammation is your body’s natural response to injury or infection such as bacteria, viruses or toxins. It is part of the immune system defense. When you get a cut or an insect bite, the area becomes red, swollen, warm and painful. These are the signs of inflammation.
Inflammation can also occur inside the body without obvious signs. Chronic (long-standing) inflammation or repeated episodes of inflammation can cause tissue damage such as joint problems and lung disease. If the immune system attacks the body’s own healthy tissues causing inflammation, this is termed an ‘autoimmune’ condition. There are many examples including lupus and some forms of arthritis.
Blood tests can indicate that there is inflammation in the body. These tests act as markers of inflammation being elevated when inflammation is active and low when it has settled or is not present.
CRP (C-reactive protein)
When high, indicates inflammation somewhere in the body
ESR (Erythrocyte Sedimentation Rate)
Similar to CRP, elevated when there is active inflammation.
Cytokines (including interleukins, interferons, tumour necrosis factor)
These small proteins help control inflammation increasing the inflammation to fight off an infection and also calming the immune response when recovering. High levels of cytokines can lead to excessive inflammation and autoimmune tissue damage.
Scans such as MRI and PET scans can be helpful in locating the source of inflammation which can sometimes be deep onside tissues.
The interferon signature
Interferons are part of the immune system. They are small proteins released by immune cells into tissues and into the blood where they help fight viruses and other infections. By analysing the genes switched on by interferons, we can tell much interferon activity is happening in the body. The pattern of which genes are turned on is called the interferon signature.
The stronger the interferon signature, the more active the immune system is, and the more active an autoimmune condition is. Doctors use the interferon signature as a measure of how active an inflammatory condition is and it can be used to detect flare-ups of a disease. In addition, it shows how well a patient might be responding to an immune treatment. Researchers look for ways of targeting or blocking the interferon response when it is excessive such as in SAVI syndrome.
Drugs such as JAK inhibitors interfere with the interferon pathway whilst anifrolumab is a recently discovered medication which specifically blocks the type 1 interferon receptor (see Resource 2 on medications and treatments).