SYDNEY: Australian scientists have found greater amounts of immune cells in the brains of some people with schizophrenia, indicating that the cells may be linked to the disease.
The study, which was published in the journal Molecular Psychiatry on Friday (Sep 14), challenges the long-held belief that immune cells were independent of brain pathology in psychotic illnesses, said Professor Cynthia Shannon Weickert from Neuroscience Research Australia (NeuRA).
According to a news release from the University of New South Wales (UNSW), no single cause of schizophrenia has been identified, and this has prevented the development of a cure.
Current treatments for schizophrenia are designed to suppress symptoms rather than target underlying causes of the disorder.
Current schizophrenia research has focused on three types of brain cells: Neurons; glial cells, which support the neurons; and endothelial cells, which coat the blood vessels.
Employing new molecular techniques, the research team identified the presence of a fourth cell, the macrophage - a type of immune cell found in the brain tissue of people with schizophrenia who show high levels of inflammation.
Prof Weickert noted that in the past, the immune cells had been thought of as benign travellers and mostly ignored. However, the discovery of large numbers in the brain of schizophrenics suggest they are more active than they once seemed.
"It suggests immune cells themselves may be producing these inflammatory signals in the brains of people living with schizophrenia,” she explained.
The study showed that in people with schizophrenia, the glial cells become inflamed and produce distress signals, which triggers a response in the endothelial cells.
“We think this may cause the endothelial cells to extend sticky tentacles, so when the immune cells travel by some are captured. These cells may transmigrate across the blood-brain barrier entering the brain in greater amounts in some people with schizophrenia compared to people without the disorder," explained Prof Weickert.
This discovery shows that specific immune cells are in the brains of some people with schizophrenia, and are in close enough proximity to the neurons to do damage.
Prof Weickert is encouraging neuroscientists and immunologists to collaborate and develop treatments targeting this abnormal immune pathology of schizophrenia.
"This opens whole new avenues for therapy," she added.