Study of the anti‐JCV antibody levels in a Spanish multiple sclerosis cohort

• Published in: European journal of clinical investigation Vol. 47; no. 2; pp. 158 - 166
• Main Authors: Dominguez‐Mozo, María I., Rus, Macarena, Santiago, Jose L., Izquierdo, Guillermo, Casanova, Ignacio, Galan, Victoria, Garcia‐Martinez, M. Angel, Arias‐Leal, Ana M., García‐Montojo, Marta, Pérez‐Pérez, Silvia, Arroyo, Rafael, Alvarez‐Lafuente, Roberto
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01-02-2017
• Subjects: Adult; Aged; Antibodies; Antibodies, Viral - metabolism; Anti‐JC virus antibodies; Demographic variables; Demographics; Drb1 protein; Enzyme-Linked Immunosorbent Assay; Female; Histocompatibility antigen HLA; Humans; Immunoglobulins; Immunologic Factors - therapeutic use; JC Virus - immunology; Leukoencephalopathy; Leukoencephalopathy, Progressive Multifocal - immunology; Longitudinal Studies; Male; Middle Aged; Monoclonal antibodies; Multiple sclerosis; Multiple Sclerosis - drug therapy; Multiple Sclerosis - immunology; natalizumab; Natalizumab - therapeutic use; Patients; Progressive multifocal leukoencephalopathy; Risk factors; Spain; Anti-JC virus antibodies; progressive multifocal leukoencephalopathy; multiple sclerosis; natalizumab
• ISSN: 0014-2972; 1365-2362
• DOI: 10.1111/eci.12721

Background
One of the risk factor to develop progressive multifocal leukoencephalopathy (PML) among natalizumab‐treated patients is the presence and high levels of anti‐JCV antibodies. Our purpose was to test the association of different clinical and demographic variables with the presence and levels of anti‐JCV antibodies in a Spanish cohort of patients with multiple sclerosis (MS) during natalizumab treatment.
Materials and methods
All patients with MS from two hospitals with at least one measure of the anti‐JCV antibodies levels (2011–2014) were recruited, among them were two PML cases. Anti‐JCV antibody levels were assessed using two‐step ELISA.
Results
A total of 1061 patients (16·3% natalizumab‐treated) participated in this study. The seropositivity rate of anti‐JCV antibodies was 58·2%. It increased with age (Pcorrected = 0·00005) and was lower among HLA‐DRB1*15:01 carriers (Pcorrected = 0·049). The two patients with PML were HLA‐DRB1*15:01 carriers. We had at least three quarterly anti‐JCV antibody measurements (index value) from 137 patients, whose levels did not increase during natalizumab treatment. However, 5·8% of these patients had an increase of the index value higher of one point in a maximum of 6 months, something that was more frequently observed (P = 0·054) among patients treated with immunosuppressant prior to natalizumab onset.
Conclusions
Old age and HLA‐DRB1*15:01 were the factors that influence positively and negatively, respectively, our anti‐JCV antibody prevalence, although our both PML cases were HLA‐DRB1*15:01carriers. Most of our patients showed a stable anti‐JCV antibody index values during natalizumab treatment.