Researchers from Benaroya Research Institute at Virginia Mason in Seattle recently conducted a study that shows unusual, exaggerate immune responses can make West Nile virus infections more severe.
There are fatal, neurologic illnesses that can develop in people who have had West Nile virus. The latest research suggests that the development of neurological symptoms may be affected by the exaggeration or abnormality of the patient’s immune response to the virus.
The study, published in PLOS Pathogens, involved blood samples from 24 different blood donors. All of the donors had experienced previous asymptomatic infections of West Nile virus. These infections, detected with laboratory tests, also showed there were 16 samples from people who had neuro-invasive disease and neurologic symptoms because of the virus.
The scientists found people who were older had an increase amount of T cells specific to the virus. These cell lines also showed that the patients were isolated from other T cells that manufacture IFN and IL-4. All of these molecules are important to keeping immune systems healthy.
The genes from CD4+ T cells because of the virus showed a distinction between the patients who had asymptomatic infections and the patients with neuroinvasive disease. The latter group showed higher groups of CD4+ T cells specific to the virus, causing a greater likelihood of the neuroinvasive disease developing.