The immune system's ability to fight germs while leaving the body's own cells alone. When it fails, the immune system can attack healthy tissue.

Autoimmune conditions happen when the immune system mounts a response against normal parts of the body.
In rheumatoid arthritis, the immune system attacks the tissues lining the joints.
In coeliac disease, the immune system reacts to gluten and damages the small bowel.

How it works

The body's own cells carry surface proteins that do not usually trigger the immune system to fight them. Sometimes the immune system mistakenly treats the body's own cells as foreign and attacks them. This is called an autoimmune response.

In allergies, the immune system makes an overly strong response to harmless allergens. Gut microbes may play an important role in training the immune system.

Connections

3 connections on the map. Select a topic to read its page.

Immune tolerance is part of

Immune system
The immune system defends against infection while protecting the body's own cells.
Sources: Better Health Channel (Victorian Government), Immune system explained; InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the immune system work?

Immune tolerance is supported by

Gut microbiome Emerging
Gut microbes may have an important role in training the immune system.
Source: Australian Academy of Science, Gut bacteria: the inside story

Immune tolerance is linked with

Autoimmunity
Sometimes the immune system mistakenly treats the body's own cells as foreign. This is called an autoimmune response.
Source: InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the immune system work?

Lab tests

Antinuclear antibodies (ANA)A blood test for antinuclear antibodies, used to screen for autoimmune rheumatic conditions such as lupus.

Sources

In brief: How does the immune system work?InformedHealth.org (IQWiG), NCBI Bookshelf, last reviewed 6 June 2023
Immune system explainedBetter Health Channel (Victorian Government), last reviewed 18 July 2022
Gut bacteria: the inside storyAustralian Academy of Science
Rheumatoid arthritishealthdirect Australia, last reviewed November 2023
Coeliac diseasehealthdirect Australia, last reviewed April 2026

Each connection above names its own source. See every source AskBioMap uses.

Summarised from InformedHealth.org, the Better Health Channel, the Australian Academy of Science and healthdirect. Sources read on 13 and 16 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.

In brief