Related Experiment Video
Updated: Apr 18, 2026

Detection of Polyfunctional T Cells in Children Vaccinated with Japanese Encephalitis Vaccine via the Flow Cytometry Technique
Published on: September 23, 2022
Markers of JC virus infection in patients with multiple sclerosis under natalizumab therapy
Valeria Clausi1, Simone Giannecchini1, Eliana Magnani1
1Department of Experimental and Clinical Medicine (V.C., S.G., F.M., A.A.) and Department of Neurosciences, Drugs and Child Health (E.M., L.M.), University of Florence; and Neurology 2 Division (A.R., C.M., L.M.), Careggi University Hospital, Florence, Italy.
Objective:
To evaluate the frequency of JC polyomavirus (JCPyV) infection and anti-JCPyV antibodies in patients with multiple sclerosis under natalizumab therapy.
Methods:
Presence of anti-JCPyV antibodies and JCPyV DNA was analyzed in 39 patients with relapsing-remitting multiple sclerosis undergoing natalizumab therapy. Anti-JCPyV antibodies were evaluated in serum by a 2-step virus-like particle-based ELISA assay (Stratify), and JCPyV DNA was evaluated in peripheral blood mononuclear cells, plasma, and urine by quantitative PCR. The anti-JCPyV antibodies were evaluated in serum samples collected at the same time or later than those collected for DNA analysis.
Results:
JCPyV DNA was detected in 59% of patients, and anti-JCPyV antibodies were present in 67%. JCPyV DNA occurred more often in blood than in urine. Anti-JCPyV antibodies were observed in 70% of the JCPyV-infected patients, and JCPyV DNA was detected in 50% of the patients without anti-JCPyV antibodies. When JCPyV DNA was investigated in blood and urine the frequency of infection was higher than previously described.
Conclusion:
Under these experimental conditions, with respect to the observed frequency of JCPyV infection, the sensitivity of the anti-JCPyV antibody assay was lower than expected.
More Related Videos
Related Concept Videos
Cytomegalovirus Disease
Multiple Sclerosis l: Introduction
Myasthenia Gravis: Diagnostic Tests
The edrophonium test is a diagnostic tool for myasthenia gravis. It involves...
Arboviral Encephalitis
Immunodeficiency Diseases
There are three main causes of immunodeficiency...
Encephalitis ll: Pathophysiology

