What is psychosis?


Psychosis is a mental health problem that causes people to perceive or interpret things differently from those around them. This might involve hallucinations or delusions, but often presents with a number of different and varied symptoms.


More information can be found on the NHS Choices website.


Support and information can also be found through the websites of the mental health charities Mind and Rethink.


Contact your GP if you think you, or someone you know, are having psychotic experiences.

What is encephalitis?


Encephalitis is a condition that causes inflammation in the brain.


Encephalitis usually begins with flu-like symptoms, and can go on to present with changes in mental state,seizures or changes in personality and behaviour.


There are a number of causes of encephalitis. One of them is when antibodies start attacking healthy parts of the brain, causing an inflammation: this condition is called autoimmune encephalitis.

What is an autoimmune disease?


The body’s immune system fights off foreign and disease-causing (pathogenic) substances.

An autoimmune disease occurs when a person's immune system begins to respond to normal bodily substances and tissues as if it were foreign or pathogenic. So the immune system starts to ‘fight off’ normal bodily tissue, which can cause further problems.


There are many known autoimmune disorders that can affect different bodily fluids and tissue. They can usually be treated with immunotherapy - where the immune system is supressed to stop the autoimmune response.


What are NMDAR, GABA-AR and LGI1 antibodies?


NMDA-r stands for 'N-methyl-D-aspartate receptor'. This is a receptor in the brain that responds to the neurotransmitter glutamate.


GABA-AR stands for 'Type A gamma-aminobutyric acid receptor'. This receptor responds to the neurotransmitter ‘GABA’, which controls the levels of excitability in the brain.


LGI1 stands for 'leucine-rich, glioma-inactivated 1', and is a protein involved in regulating neuronal excitability.


Recent studies have shown that there are autoimmune diseases that produce antibodies to specifically target parts of NMDA and GABA-A receptors and LGI1 proteins and disrupt their function.


Our PPiP2 study is investigating how commonly these antibodies are present in patients experiencing psychosis.


Our SINAPPS2 clinical trial is investigating whether people with these antibodies who are experiencing psychosis get better after being treated with immunotherapy.






What is antibody-associated psychosis?


The latest research suggests that 9% of people with psychosis have antibodies in their blood which could be the cause of their illness.


Our immune system normally protects us against infections. It does this by making antibodies,  proteins which the body produces to fight infections. However, for a very small number of people, some antibodies (called anti-neuronal antibodies) start to attack healthy brain tissue causing swelling. This can result in symptoms of psychosis, including hallucinations and paranoid feelings. There is some evidence that getting rid of these antibodies may improve the symptoms of psychosis.


Antibody associated psychosis is very similar to a condition called encephalitis. The conditions are so similar that some believe that antibody associated psychosis might be a specific type of encephalitis (the term ‘anti-NMDA encephalitis is sometimes used in place of ‘antibody associated psychosis).


(extracted from Antibody Mediated Psychosis information and resources from the public, The McPin Foundation)