The laboratory of Igor Koralnik, MD, in the Department of Neurology studies how viruses affect the nervous system. These include SARS-CoV-2 in patients with COVID-19, HIV in patients with substance use, as well as the entire Virome in patients with neurodegenerative diseases. In addition, we are involved in Global Neurology research with our international partners.
Our Work
How does COVID-19 affects the nervous system?
At the beginning of the pandemic, Dr. Koralnik created one of the first Neuro-COVID-19 clinics in the US, where he has evaluated >1000 patients in the first 18 months. These include two very different groups of patients: those who were hospitalized with severe COVID-19 pneumonia and had neurologic complications, and those who were never hospitalized and had mild initial respiratory presentation, but now present with debilitating neurologic symptoms of the Long-Covid syndrome.
Our laboratory is studying how the immune response to SARS-CoV-2 is dysregulated in those patients compared to asymptomatic COVID-19 convalescents, and whether Long Covid patients may have persistent infection in hidden reservoirs that drives this immune response. In addition, we are also studying biomarkers of CNS injury, disruption of circadian rhythms, and effect of cognitive rehabilitation on cognitive dysfunction in this very well clinically characterized population.
What is the role of viruses in neurodegenerative diseases?
Viruses have been implicated in a number of degenerative diseases of the Nervous system. The inherent weakness of current detection methods for viruses relies on the need for species-specific PCR primers, the “one test-one virus” paradigm. To resolve this limitation, we have designed ViroFind, a high-efficiency targeted enrichment sequencing platform for virus detection and discovery in clinical samples, including 565 human viruses or viruses that could cause zoonosis, representing all known species to date – the entire Virome.
Using this novel assay, we have tested fresh frozen post mortem brain samples from patients with Alzheimer’s and Parkinson’s disease, and have identified unique viral species associated with those diseases. Our laboratory is now studying the prevalence of those viruses in brain, CSF and blood samples from patients, as well as the type of cells that are infected in FFPE brain tissue. We are also studying the pathogenic mechanisms of those viruses in vitro, that may lead to Neurodegeneration.
What is the role of the Virome in HIV/AIDS pathogenesis and in substance use?
Patients with HIV/AIDS are immunosuppressed and liable to be infected by other viruses. Recurrent reactivations in the setting of immunosuppression may trigger an immune, metabolic or chemical imbalance that may contribute to drug addiction in certain individuals.
We are using ViroFind to characterize the entire virome in post mortem brain samples of HIV/AIDS patients and control subjects with and without substance use. We are also studying the virome in blood samples from HIV-infected Zambian patient patients with and without substance use.
How can we promote Neurologic care, research and education at the Global level?
In 2010, Dr. Koralnik created the first Global Neurology research program in Lusaka, Zambia. Over the years, this program grew tremendously and is now a multi-institutional consortium, the Zambia Institute for Neurological Care, Research and Education (ZINCARE). Dr. Koralnik also helped develop the first Neurology Residency training program for Zambian Neurologists, and the first class of Zambian adult and pediatric neurologists graduated in 2020.
He and his colleagues are studying various aspects of Neuro-Infectious diseases in Zambia. We are also collaborating on Neuro-COVID-19 and Viromics research in neurodegenerative diseases in Zambia, as well as other sites in Africa, Latin America. Dr. Koralnik is also the Director of the Program for Global Neurology within the Institute for Global Health at Northwestern.