Absence of JC polyomavirus in stool samples of patients with multiple sclerosis despite high anti-JCV antibodies in serum.

BACKGROUND: Natalizumab is an effective treatment for relapsing multiple sclerosis (MS). During therapy, individuals are at increased risk of developing progressive multifocal leukoencephalopathy (PML). So far, the relevant reservoir for PML-type JC polyomavirus (JCV) remains elusive. We here tested if the detection of JCV-DNA in stool of persons with MS treated with natalizumab could be a future tool for PML risk assessment. METHODS: The presence of JCV-DNA in stool, urine, and whole blood of MS patients treated with natalizumab and known serum anti-JCV antibodies index values (IV) was studied. Different DNA extraction methods, real-time (RT) and droplet digital (dd) PCR techniques were compared. JCV isolates were screened for PML-associated variants by sequencing. RESULTS: Thirty MS patients treated with natalizumab were screened. For 21 patients, blood, stool, and urine samples were available. These patients were stratified according to their serum anti-JCV antibody IV (high (>1.5, n = 12); medium (1.5-0.9, n = 2); low (<0.9, n = 1); negative (n = 6)). JCV-DNA could not be detected in the whole blood or stool samples. Four urine samples had measurable JCV-DNA, ranging from 1.71×104-1.07×108 international units (IU)/mL detected by RT-PCR, corresponding to 4.62×104-9.85×106 copies/mL measured by ddPCR. All JCV variants were wild-type and derived from patients with high antibody IV. CONCLUSION: Stool-specific DNA extraction methods provided the highest quality of DNA, while the sensitivity of ddPCR and RT- PCR was comparable. Our findings do not support assessing stool samples for PML risk stratification in persons with MS. Further studies are needed to explore where PML-associated viral variants arise.

Association of B-cell activating factor gene variants with serum anti-JCV antibody positivity in male patients with multiple sclerosis under natalizumab treatment: Implications for progressive multifocal leukoencephalopathy risk stratification.

INTRODUCTION: Progressive multifocal leukoencephalopathy (PML) is a potentially life-threatening complication among Multiple Sclerosis (MS) patients under natalizumab treatment, with serum anti-JCV antibody titers being used for stratification risk. Given the critical role of interferon (IFN)/B-cell activating factor (BAFF) axis in humoral immune responses against viruses, we explored whether it is involved in the generation of serum anti-JCV antibodies among these patients. METHODS: 162 consecutive patients with relapsing-remitting MS under natalizumab treatment were included. Serum anti-JCV antibodies were measured at baseline, as well as 12 and 24 months after treatment initiation. Type I and II IFN-inducible genes and BAFF expression were quantitated in peripheral blood by qRT-PCR. Moreover, BAFF rs9514828, rs1041569, and rs9514827 gene variants were assessed by RFLP-PCR. RESULTS: While type I and II IFN inducible gene expression were not associated with anti-JCV serum titers, the latter were significantly correlated with BAFF gene expression. Of interest, the TTT haplotype of the studied BAFF variants was more frequently detected in male, but not female anti-JCV (+) MS patients compared to anti-JCV (-) counterparts at baseline, as well as at 12 months and 24 months of natalizumab treatment. Measures of clinical validity/utility for the BAFF TTT haplotype showed 88% specificity, 45%, positive predictive value, and sensitivity of 70% for the discrimination of anti-JCV (+) male MS patients after 24 months of treatment. CONCLUSIONS: Our study suggests an implication of the BAFF axis in the production of serum anti-JCV antibodies. Additionally, the BAFF TTT haplotype derived from the rs9514828, rs1041569, and rs9514827 variants may represent a novel risk factor for anti-JCV seropositivity and indirectly for PML development among male MS patients treated with natalizumab.

Risk Assessment of Progressive Multifocal Leukoencephalopathy in Multiple Sclerosis Patients during 1 Year of Ocrelizumab Treatment.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) caused by the JC virus is the main limitation to the use of disease modifying therapies for treatment of multiple sclerosis (MS). METHODS: To assess the PML risk in course of ocrelizumab, urine and blood samples were collected from 42 MS patients at baseline (T0), at 6 (T2) and 12 months (T4) from the beginning of therapy. After JCPyV-DNA extraction, a quantitative-PCR (Q-PCR) was performed. Moreover, assessment of JCV-serostatus was obtained and arrangements' analysis of non-coding control region (NCCR) and of viral capsid protein 1 (VP1) was carried out. RESULTS: Q-PCR revealed JCPyV-DNA in urine at all selected time points, while JCPyV-DNA was detected in plasma at T4. From T0 to T4, JC viral load in urine was detected, increased in two logarithms and, significantly higher, compared to viremia. NCCR from urine was archetypal. Plasmatic NCCR displayed deletion, duplication, and point mutations. VP1 showed the S269F substitution involving the receptor-binding region. Anti-JCV index and IgM titer were found to statistically decrease during ocrelizumab treatment. CONCLUSIONS: Ocrelizumab in JCPyV-DNA positive patients is safe and did not determine PML cases. Combined monitoring of ocrelizumab's effects on JCPyV pathogenicity and on host immunity might offer a complete insight towards predicting PML risk.

Serum Neurofilament Levels and PML Risk in Patients With Multiple Sclerosis Treated With Natalizumab.

OBJECTIVES: The study aimed to assess the potential for serum neurofilament light chain (NFL) levels to predict the risk of progressive multifocal leukoencephalopathy (PML) in natalizumab (NTZ)-treated patients with multiple sclerosis (MS) and to discriminate PML from MS relapses. METHODS: NFL levels were measured with single molecule array (Simoa) in 4 cohorts: (1) a prospective cohort of patients with MS who developed PML under NTZ therapy (pre-PML) and non-PML NTZ-treated patients (NTZ-ctr); (2) a cohort of patients whose blood was collected during PML; (3) an independent cohort of non-PML NTZ-treated patients with serum NFL determinations at 2 years (replication cohort); and (4) a cohort of patients whose blood was collected during exacerbations. RESULTS: Serum NFL levels were significantly increased after 2 years of NTZ treatment in pre-PML patients compared with NTZ-ctr. The prognostic performance of serum NFL levels to predict PML development at 2 years was similar in the NTZ-ctr group and replication cohort. Serum NFL levels also distinguished PML from MS relapses and were 8-fold higher during PML compared with relapses. CONCLUSIONS: These results support the use of serum NFL levels in clinical practice to identify patients with relapsing-remitting MS at higher PML risk and to differentiate PML from clinical relapses in NTZ-treated patients. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that serum NFL levels can identify NTZ-treated patients with MS who will develop PML with a sensitivity of 67% and specificity of 80%.

Progressive multifocal leukoencephalopathy in an elderly immunocompetent-appearing patient: Relevance with L-selectin (CD62L) expression and immunosenescence.

Progressive multifocal leukoencephalopathy (PML) is attributed to reactivation of the John Cunningham virus (JCV), in the central nervous system as a result of immunosuppression. Low L-selectin (CD62L) expression on cryopreserved T-cells has been advocated as a biomarker for natalizumab related PML in patients with Relapsing-Remitting Multiple Sclerosis. A rare case of PML in an elderly patient without known factors of immunosuppression or immunomodulation is hereby presented. T-cell L-selectin expression levels and serum anti-JCV antibody index were evaluated in order to explore mechanistic insight to the pathways that presumably contribute towards PML development in this rare clinical setting.

Improving risk-stratification of natalizumab-associated PML.

Based on publicly available data, we reevaluated current algorithms for stratifying the risk of progressive multifocal leukoencephalopathy (PML) in natalizumab-treated patients with multiple sclerosis, and found that there are a number of issues. First and foremost, our analysis highlights the necessity of separate PML incidence assessments for the U.S. versus Europe, and indicates that the risk in John Cunningham virus (JCV) antibody-negative patients may be higher than previously communicated. Additionally, we advocate introducing a low-risk JCV index threshold of 0.45 for individuals with prior exposure to an immunosuppressant, and setting the low-risk threshold at 0.6 instead of 0.9 for those without such pretherapies. On the other hand, the risk of PML on natalizumab, in general, appears to not only plateau but to actually decrease after about 5 years of continuous dosing.

"Borderline" idiopathic CD4+ T-cell lymphocytopenia presenting with atypical progressive multifocal leukoencephalopathy.

Idiopathic CD4+ lymphocytopenia (ICL) is a rare disorder characterized by low counts of CD4+ cells (<300/mm3) in absence of other known causes of immunosuppression. A few cases of progressive multifocal leukoencephalopathy (PML) were reported in association with ICL with variable outcome. We describe the case of a 40 year-old man diagnosed with PML, which showed a monophasic course. Causes of primary and secondary immunodeficiency were ruled out, only a "borderline" ICL was found. This case highlights that a severe immunodepression could not be an absolute prerequisite in developing PML and also points the attention on current definition of ICL.

Which is the best PML risk stratification strategy in natalizumab-treated patients affected by multiple sclerosis?

BACKGROUND: The risk of progressive multifocal leukoencephalopathy (PML), a brain infection caused by John Cunningham virus (JCPyV), is the main limitation to the use of natalizumab, highly effective in the treatment of relapsing remitting multiple sclerosis (RRMS) patients. Establishing the PML risk against expected benefits represents an obligatory requirement of MS treatment algorithm. In order to achieve this goal, the aims of this study were to establish if JCPyV-DNA detection and non-coding control region (NCCR) arrangements could play a role of biomarkers, supporting anti-JCPyV antibodies measurement, actually the only parameter for PML risk stratification. METHODS: Thirty RRMS patients in treatment with natalizumab were enrolled. Urine and blood samples were collected according to this calendar: baseline (T0), 4 (T1), 8 (T2), 12 (T3), 16 (T4), 20 months (T5) after beginning of natalizumab therapy. After JCPyV DNA extraction, a specific quantitative-PCR (Q-PCR) and arrangements' analysis of NCCR and Viral Capsid Protein 1 (VP1) were carried out. RESULTS: Q-PCR detected JCPyV DNA in urine and blood from baseline (T0) to 20 natalizumab infusions (T5), although JC viral load in urine was significantly higher compared to viremia, at all selected time points. A contextual analysis of the anti-JCPyV-antibodies versus JCPyV-DNA detection revealed that viral DNA preceded the antibodies' presence in the serum. During the first year of natalizumab treatment, sequences isolated from blood displayed an archetype JCPyV NCCR structure with the occurrence of point mutations, whereas after one year NCCR re-organizations were observed in plasma and PBMC with duplication of NF-1 binding site in box F, duplication of box C and partial or total deletion of box D. VP1 analysis showed the amino acid change mutation S269F in plasma and S267L in PBMC, involving the receptor-binding region of VP1. Phylogenetic analysis suggested a stability and a similarity across different isolates of the JCPyV VP1. CONCLUSIONS: We highly recommend considering JCPyV-DNA detection and NCCR re-organizations as viral biomarkers in order to accurately identify JCPyV-infected patients with a specific humoral response not yet detectable and to identify NCCR arrangements correlated with the onset of neurovirulent variants.

Early reduction of the splicing factor2/alternative splicing factor: a cellular inhibitor of the JC polyomavirus in natalizumab-treated MS patients long before developing progressive multifocal leukoencephalopathy.

Natalizumab is effective against relapsing-remitting multiple sclerosis (MS) but increases the risk of progressive multifocal leukoencephalopathy (PML), which is caused by the activation of the JCV polyomavirus. SF2/ASF (splicing factor2/alternative splicing factor) is a potent cellular inhibitor of JCV replication and large T-antigen (T-Ag) expression. We reported that SF2/ASF levels in blood cells increase during the first year of natalizumab therapy and decrease thereafter, inversely related to T-Ag expression, and suggested a correlation with JCV reactivation. Here, we report SF2/ASF levels of longitudinal blood samples of two patients undergoing natalizumab therapy, who developed PML while monitored, in comparison to natalizumab-treated controls and to one-off PML samples. After 6 months of therapy, SF2/ASF levels of the two cases were reduced, instead of increased, and their overall SF2/ASF levels were lower than those from natalizumab controls. Since SF2/ASF inhibits JCV, its early reduction might have a role in subsequent PML. We are aware of the limitations of the study, but the uniqueness of serial blood samples collected before and after PML onset in natalizumab-treated patients must be stressed. If confirmed in other patients, SF2/ASF evaluation could be a new and early biomarker of natalizumab-associated PML risk, allowing an 18-24-month interval before PML onset (presently ~ 5 months), in which clinicians could evaluate other risk factors and change therapy.

Progressive multifocal leukoencephalopathy in idiopathic CD4+ lymphocytopenia: A case report and review of literature.

Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease due to a lytic infection of oligodendrocytes caused by polyoma virus (JC virus) infection. PML usually occurs in a setting of severe immunosuppression and is most commonly associated with human immunodeficiency virus (HIV) infection. Idiopathic CD4+ lymphocytopenia is a very rare cause of PML and only a few cases have been reported in the literature. We present a case of a 45-year-old man who presented with behavioral alteration followed by progressive weakness of right side of the body. Contrast-enhanced magnetic resonance imaging of the brain revealed confluent irregular areas of T2-weighted/fluid-attenuated inversion recovery hyperintensities in left frontoparietal and right temporoparietal regions. His hematological work up showed a decreased absolute CD4+ count of 217 per microliter, but was negative for HIV serology. Keeping a differential diagnoses of central nervous system lymphoma, brain biopsy was performed. Histopathology revealed demyelination with presence of intranuclear inclusions in the oligodendrocytes, which were positive for SV40 immunostain. Adjacent areas showed reactive gliosis with hypertrophic astrocytes, hence a diagnosis of PML was made. The patient died due to aspiration pneumonia. PML can occur very rarely in association with idiopathic CD4+ lymphocytopenia in the absence of other immunosuppressive illnesses. This report highlights the importance of high index of clinical suspicion and need for a careful histological examination for diagnosis of PML to facilitate adequate patient management.

Predictive value of JC virus PCR in cerebrospinal fluid in the diagnosis of PML.

OBJECTIVE: To assess the predictive value of JC virus (JCV) PCR in cerebrospinal fluid (CSF) in the diagnosis of progressive multifocal leukoencephalopathy (PML). METHODS: We conducted a retrospective database query to identify patients with positive CSF JCV PCR. Clinical features, final diagnosis and quantitative PCR results were obtained. RESULTS: A positive CSF JCV PCR had a PPV of 10.4% for the diagnosis of PML. A weakly positive PCR had a PPV of 1.6%, whereas a moderately to highly positive PCR had a PPV of 92.3%. A PPV of 0.0% was observed in immunocompetent patients and in patients without compatible clinical or radiological features. CONCLUSIONS: A false-positive CSF JCV PCR is highly prevalent in our clinical practice. This test should be reserved for patients with a clinical suspicion of PML and the quantitative result of the PCR should be taken into account when making the diagnosis of PML.

Natalizumab-associated progressive multifocal leukoencephalopathy in Germany.

OBJECTIVE: To evaluate characteristics relevant to diagnosis of JC polyomavirus-associated progressive multifocal leukoencephalopathy (PML), and PML risk stratification in a large national cohort of patients with multiple sclerosis during therapy with natalizumab. METHODS: Analysis of 292 adverse drug reaction forms on suspected cases of PML reported to the German national competent authority until July 2017. Patients not fulfilling PML diagnostic criteria or with insufficient information available were excluded. RESULTS: Of the 142 confirmed patients with PML, 72.3% (95% confidence interval [CI] 64.4%-79.1%) were women, and the median age was 43 years (range 19-69). Of these patients, 7.7% (95% CI 4.3%-13.5%) were clinically asymptomatic at time of PML diagnosis. PML was fatal in 9.1% (95% CI 5.3%-15.1%) of the patients. Infratentorial lesions on imaging were reported in 40% (95% CI 32.0%-48.6%) of the patients. JC polyomavirus DNA in CSF was undetectable at time of first analysis in 23.8% (95% CI 17.3%-31.9%) of the patients. Three patients tested negative for anti-JC polyomavirus antibodies within 6 to 18 months before PML diagnosis, with seroconversion confirmed 5.5 months, 7 months (in a post hoc analysis only), or at time of PML diagnosis. CONCLUSIONS: JC polyomavirus DNA detection in CSF has limited sensitivity in early PML, and clinical and imaging presentation may be atypical. Thus, critical revision of current PML diagnostic criteria is warranted. Negative anti-JC polyomavirus antibodies in sera do not preclude the later development of PML. This emphasizes the need for close and regular serologic, imaging, and clinical monitoring in patients treated with natalizumab.

Serum neurofilaments increase at progressive multifocal leukoencephalopathy onset in natalizumab-treated multiple sclerosis patients.

This study analyzed serum neurofilament light chains (NfL) in 2 European cohorts of 312 multiple sclerosis (MS) patients to investigate whether NfL are biomarkers of progressive multifocal leukoencephalopathy (PML) during natalizumab treatment. The cohort comprised 25 PML, 136 natalizumab-treated, and 151 untreated MS patients. Patients subsequently developing PML had similar NfL to other natalizumab-treated MS patients. At PML onset, NfL were 10-fold higher than in the pre-PML condition and in natalizumab-treated or untreated MS patients, and NfL continued to increase until onset of immune reconstitution inflammatory syndrome. The results suggest that in natalizumab-treated patients, NfL may represent an early and accessible marker of PML. Ann Neurol 2019;85:606-610.

Serological profile of John Cunningham virus (JCV) in patients with multiple sclerosis.

Treatment options for multiple sclerosis (MS) have changed over the last few years, bringing about a new category of drugs with more efficient profiles. However, these drugs have come with a whole new profile of potential adverse events that neurologists have to learn well and quickly. One of the most feared complications of these MS treatments is progressive multifocal leukoencephalopathy caused by the reactivation of the John Cunningham virus (JCV). OBJECTIVE: To identify the serologic profile of JCV in patients with MS. METHODS: Data on serum antibodies for JCV were obtained using the enzyme-linked immunosorbent assay provided by the STRATIFY-JCV program. RESULTS: A total of 1,501 blood tests were obtained from 1,102 patients with MS. There were 633 patients (57.1%) who were positive for antibodies for JCV and 469 patients who were negative (42.9%). Twenty-three patients became positive after initially having negative JCV antibody status. The rate of seroconversion was 18.5% over 22 months. CONCLUSION: The JCV serologic profile and seroconversion in Brazilian patients were similar to those described in other countries.

Serological profile of John Cunningham virus (JCV) in patients with multiple sclerosis / Perfil sorológico do vírus John Cunningham (JCV) em pacientes com esclerose múltipla

ABSTRACT Treatment options for multiple sclerosis (MS) have changed over the last few years, bringing about a new category of drugs with more efficient profiles. However, these drugs have come with a whole new profile of potential adverse events that neurologists have to learn well and quickly. One of the most feared complications of these MS treatments is progressive multifocal leukoencephalopathy caused by the reactivation of the John Cunningham virus (JCV). Objective: To identify the serologic profile of JCV in patients with MS. Methods: Data on serum antibodies for JCV were obtained using the enzyme-linked immunosorbent assay provided by the STRATIFY-JCV program. Results: A total of 1,501 blood tests were obtained from 1,102 patients with MS. There were 633 patients (57.1%) who were positive for antibodies for JCV and 469 patients who were negative (42.9%). Twenty-three patients became positive after initially having negative JCV antibody status. The rate of seroconversion was 18.5% over 22 months. Conclusion: The JCV serologic profile and seroconversion in Brazilian patients were similar to those described in other countries.

RESUMO As opções terapêuticas para esclerose múltipla (EM) modificaram-se ao longo dos últimos anos, trazendo uma nova categoria de drogas com melhor perfil de eficácia. No entanto, estas drogas vieram com um novo perfil de potenciais eventos adversos que exigem que o neurologista os reconheça bem e rapidamente. Uma das complicações mais temidas destes tratamentos para a EM é a leucoencefalopatia multifocal progressiva (LEMP), causada pela reativação do vírus John Cunningham (JCV). Objetivo: Identificar o perfil sorológico de JCV em pacientes com EM. Métodos: Dados sorológicos de JCV foram obtidos através do ensaio por enzimas imuno-adsorvidas (ELISA) fornecido pelo programa STRATIFY-JCV. Resultados: Um total de 1.501 testes sanguíneos foram obtidos de 1.102 pacientes com EM. O grupo teve 633 pacientes (57,1%) soropositivos para anticorpos anti-JCV e 469 pacientes negativos (42,9%). Vinte e três pacientes se tornaram posivitos após resultados iniciais negativos para anticorpos anti-JCV. A taxa de soroconversão foi 18,5% em 22 meses. Conclusão: O perfil sorológico do JCV e a soroconversão nos pacientes brasileiros foi semelhante àquela descrita em outros países.

Anti-JC virus antibody index changes in rituximab-treated multiple sclerosis patients.

Rituximab, a monoclonal antibody to CD20, is an effective treatment for relapsing remitting multiple sclerosis (MS) reducing relapse rate by at least 50% over time. Although the mechanism for this clinical benefit is unclear, rituximab depletes circulating B cells, which can perform antigen presentation and stimulation of T cells. Another anti-CD20 drug, ocrelizumab, has recently been FDA approved to treat both relapsing remitting and progressive forms of MS. While long-term effects of ocrelizumab use are essentially unknown, long-term use of rituximab has been associated with the development of progressive multifocal leukoencephalopathy (PML) at an incidence of approximately 1/25,000 in non-MS conditions. Serostatus for JC virus (JCV), the causative agent for PML, is an important risk stratification tool for natalizumab, but its utility in other MS treatments is uncertain. We found that rituximab use was associated with a reduction in JCV antibody index values in MS patients. Reductions in immunoglobulins, IgM in particular, are seen in concert with JCV antibody reductions. Physicians should exercise caution when using JCV antibody indices to assess any risk of PML for patients on rituximab.

JC Virus-DNA Detection Is Associated with CD8 Effector Accumulation in Peripheral Blood of Patients with Multiple Sclerosis under Natalizumab Treatment, Independently from JC Virus Serostatus.

Although natalizumab (anti-α4 integrin) represents an effective therapy for relapsing remitting multiple sclerosis (RRMS), it is associated with an increased risk of developing progressive multifocal leukoencephalopathy (PML), caused by the polyomavirus JC (JCV). The aim of this study was to explore natalizumab-induced phenotypic changes in peripheral blood T-lymphocytes and their relationship with JCV reactivation. Forty-four patients affected by RRMS were enrolled. Blood and urine samples were classified according to natalizumab infusion number: 0 (N0), 1-12 (N12), 13-24 (N24), 25-36 (N36), and over 36 (N > 36) infusions. JCV-DNA was detected in plasma and urine. T-lymphocyte phenotype was evaluated with flow cytometry. JCV serostatus was assessed. Ten healthy donors (HD), whose ages and sexes matched with the RRMS patients of the N0 group, were enrolled. CD8 effector (CD8 E) percentages were increased in natalizumab treated patients with detectable JCV-DNA in plasma or urine compared to JCV-DNA negative patients (JCV-) (p < 0.01 and p < 0.001, resp.). Patients with CD8 E percentages above 10.4% tended to show detectable JCV-DNA in plasma and/or urine (ROC curve p = 0.001). The CD8 E was increased when JCV-DNA was detectable in plasma or urine, independently from JCV serology, for N12 and N24 groups (p < 0.01). As long as PML can affect RRMS patients under natalizumab treatment with a negative JCV serology, the assessment of CD8 E could help in the evaluation of JCV reactivation.