LUIZ HENRIQUE DA SILVA NALI
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina
3 resultados
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- Genomic analysis of ERVWE2 locus in patients with multiple sclerosis: absence of genetic association but potential role of human endogenous retrovirus type W elements in molecular mimicry with myelin antigen(2013) OLIVAL, Guilherme S. do; FARIA, Thiago S.; NALI, Luiz H. S.; OLIVEIRA, Augusto C. P. de; CASSEB, Jorge; VIDAL, Jose E.; CAVENAGHI, Vitor B.; TILBERY, Charles P.; MORAES, Lenira; FINK, Maria C. S.; SUMITA, Laura M.; PERRON, Herve; ROMANO, Camila M.Human endogenous retroviruses (HERVs) arise from ancient infections of the host germline cells by exogenous retroviruses, constituting 8% of the human genome. Elevated level of envelope transcripts from HERVs-W has been detected in CSF, plasma and brain tissues from patients with Multiple Sclerosis (MS), most of them from Xq22.3, 15q21.3, and 6q21 chromosomes. However, since the locus Xq22.3 (ERVWE2) lack the 5' LTR promoter and the putative protein should be truncated due to a stop codon, we investigated the ERVWE2 genomic loci from 84 individuals, including MS patients with active HERV-W expression detected in PBMC. In addition, an automated search for promoter sequences in 20 kb nearby region of ERVWE2 reference sequence was performed. Several putative binding sites for cellular cofactors and enhancers were found, suggesting that transcription may occur via alternative promoters. However, ERVWE2 DNA sequencing of MS and healthy individuals revealed that all of them harbor a stop codon at site 39, undermining the expression of a full-length protein. Finally, since plaque formation in central nervous system (CNS) of MS patients is attributed to immunological mechanisms triggered by autoimmune attack against myelin, we also investigated the level of similarity between envelope protein and myelin oligodendrocyte glycoprotein (MOG). Comparison of the MOG to the envelope identified five retroviral regions similar to the Ig-like domain of MOG. Interestingly, one of them includes T and B cell epitopes, capable to induce T effector functions and circulating Abs in rats. In sum, although no DNA substitutions that would link ERVWE2 to the MS pathogeny was found, the similarity between the envelope protein to MOG extends the idea that ERVEW2 may be involved on the immunopathogenesis of MS, maybe facilitating the MOG recognizing by the immune system. Although awaiting experimental evidences, the data presented here may expand the scope of the endogenous retroviruses involvement on MS pathogenesis.
- Natalizumab treatment for multiple sclerosis: updates and considerations for safer treatment in JCV positive patients(2014) NALI, Luiz Henrique da Silva; MORAES, Lenira; FINK, Maria Cristina Domingues; CALLEGARO, Dagoberto; ROMANO, Camila Malta; OLIVEIRA, Augusto Cesar Penalva deNatalizumab is currently one of the best options for treatment of patients with Multiple Sclerosis who have failed traditional prior therapies. However, prolonged use, prior immunosuppressive therapy and anti-JCV antibody status have been associated with increased risk of developing progressive multifocal leukoencephalopathy (PML). The evaluation of these conditions has been used to estimate risks of PML in these patients, and distinct (sometimes extreme) approaches are used to avoid the PML onset. At this time, the biggest issue facing the use of Natalizumab is how to get a balance between the risks and the benefits of the treatment. Hence, strategies for monitor JCV-positive patients undergoing Natalizumab treatment are deeply necessary. To illustrate it, we monitored JCV/DNA in blood and urine of a patient receiving Natalizumab for 12 months. We also bring to discussion the effectiveness of the current methods used for risk evaluation, and the real implications of viral reactivation.
- Polyomavirus Detection in Multiple Sclerosis Patients Under Natalizumab Therapy: Profile and Frequency of Urinary Shedding(2017) NALI, Luiz Henrique; FINK, Maria Cristina; OLIVAL, Guilherme S. do; MORAES, Lenira; CALLEGARO, Dagoberto; TILBERY, Charles Peter; VIDAL, Jose Ernesto; SUMITA, Laura Masami; OLIVEIRA, Augusto C. Penalva de; ROMANO, Camila M.Patients undergoing Natalizumab (NTZ) therapy are at risk of progressive multifocal leukoence-phalopathy (PML). Besides John Cunningham virus (JCV), BK polyomavirus might represent an additional concern for such patients since it can also infect CNS cells. Currently, data regarding the presence of anti-JCV antibodies added to previous immunosuppressive therapy and prolonged NTZ therapy has been used to classify patients at risk of developing PML. Here, we investigated the profile shedding of JCV and BKV in multiple sclerosis (MS) patients during treatment with NTZ. Serial blood and urine samples from 97 MS patients receiving either NTZ or beta-interferon were investigated for polyomavirus shedding. While all blood samples tested negative, 36% of the patients shed polyomavirus in the urine in at least one time point. From these, 21.7%, 9.3%, and 5.1% shed JCV, BKV, and both polyomavirus, respectively. No difference was observed between the rates of urinary shedding of patients treated with NTZ (38.9%) and patients treated with other drugs (34.5%), also no PML event was diagnosed during the follow-up. Therefore, urinary shedding might not be interfered by therapy condition. In our study, we also observed 14/ 27 (52%) of anti-JCV antibodies prevalence, and nearly half of them (42%) did not present any event of urinary shedding during the follow-up. (C) 2016 Wiley Periodicals, Inc.