Association between Immune Activity and Schizophrenia

According to a study presented in the American Journal of Psychiatry, immune cells are much more active in the brains of individuals at risk of schizophrenia, along with those previously diagnosed with the condition.

The discovery could provide a new strategy to treating this chronic, condition that has impacted people throughout history.

Schizophrenia is reported in 1% of the common population, but it occurs in 10% of individuals who have a first-degree family member with the condition, such as a parent, brother or sister.

Therapy for the condition so far has targeted on an imbalance in the complex, interrelated-chemical responses of the brain. By focusing on the neurotransmitters dopamine and glutamate, antipsychotic medications have been prescribed to manage it. However, the medicines usually have side effects, and if individuals quit taking them, the condition is known to relapse.

The new results raise the possibility that early examination of those most at risk could allow them to be treated early enough to prevent the most serious symptoms of the disease.

Investigators at the Medical Research Council’s (MRC) Clinical Sciences Centre, based at Imperial College London – in alliance with colleagues at King’s College London – used positron emission tomography (PET) tests to evaluate levels of activity of immune cells in the brain.

Greater levels of microglia in individuals with schizophrenia

The immune cells, well-known as microglia, react to damage and infection in the brain. They are also accountable for “pruning,” where connections among brain cells are rearranged.

The research team examined a group of 56 individuals, of whom some were previously diagnosed with schizophrenia, some people were at risk of the condition and others had no signs or risk of the condition.

They identified that activity levels of microglia in the brain enhanced in proportion to the intensity of symptoms in individuals with schizophrenia, and that individuals with diagnosed schizophrenia had great levels of activity of these immune cells in their brain.

Lead author of the research, Peter Bloomfield, states that

“Our results are interesting due to the fact it was earlier unknown whether these cells turn out to be active before or after beginning of the disease. Now we have proven this early involvement, mechanisms of the condition and new drugs can hopefully be discovered.”

The results of schizophrenia can be destructive for patients and family members. Individuals may experience delusions or hallucinations and think that other individuals are studying their minds, managing their thoughts or planning to harm them. This can scare individuals with the illness and make them withdrawn or highly agitated.

Dangerous or improper behavior can also result in some risk of drug abuse and suicide. Many individuals with schizophrenia have problems holding a job or caring for themselves, so they depend on others for help.

Head of the psychiatric imaging group at the MRC Clinical Sciences Centre, Dr. Oliver Howes explains schizophrenia as a “possibly devastating condition,” for which new therapies are certainly required. He thinks this research is promising, as it indicates that inflammation may result in schizophrenia and other psychotic conditions, pointing the way for new developments.

The following step will be to test if anti-inflammatory therapies can focus on such conditions, to enable the disorders to be handled in a more successful way, or better still, prevented.

Prof. Hugh Perry, incharge of the Neuroscience and Mental Health Board at the MRC, states that we know that genetic and behavioral aspects play a role in schizophrenia, but to discover that inflammation in the brain could be an aspect brings hope for life-changing therapies. He adds that there could also be implications for other conditions, like as Alzheimer’s disease and depression.