Natalizumab affects T-cell phenotype in multiple sclerosis: implications for JCV reactivation

The anti-CD49d monoclonal antibody natalizumab is currently an effective therapy against the relapsing-remitting form of multiple sclerosis (RRMS). Natalizumab therapeutic efficacy is limited by the reactivation of the John Cunningham polyomavirus (JCV) and development of progressive multifocal leukoencephalopathy (PML). To correlate natalizumab-induced phenotypic modifications of peripheral blood T-lymphocytes with JCV reactivation, JCV-specific antibodies (serum), JCV-DNA (blood and urine), CD49d expression and relative abundance of peripheral blood T-lymphocyte subsets were longitudinally assessed in 26 natalizumab-treated RRMS patients. Statistical analyses were performed using GraphPad Prism and R. Natalizumab treatment reduced CD49d expression on memory and effector subsets of peripheral blood T-lymphocytes. Moreover, accumulation of peripheral blood CD8+ memory and effector cells was observed after 12 and 24 months of treatment. CD4+ and CD8+ T-lymphocyte immune-activation was increased after 24 months of treatment. Higher percentages of CD8+ effectors were observed in subjects with detectable JCV-DNA. Natalizumab reduces CD49d expression on CD8+ T-lymphocyte memory and effector subsets, limiting their migration to the central nervous system and determining their accumulation in peripheral blood. Impairment of central nervous system immune surveillance and reactivation of latent JCV, can explain the increased risk of PML development in natalizumab-treated RRMS subjects

Repair of Parastomal Hernias with Biologic Grafts: A Systematic Review

Contains fulltext : 98303.pdf (publisher's version ) (Open Access)BACKGROUND: Biologic grafts are increasingly used instead of synthetic mesh for parastomal hernia repair due to concerns of synthetic mesh-related complications. This systematic review was designed to evaluate the use of these collagen-based scaffolds for the repair of parastomal hernias. METHODS: Studies were retrieved after searching the electronic databases MEDLINE, EMBASE and Cochrane CENTRAL. The search terms 'paracolostomy', 'paraileostomy', 'parastomal', 'colostomy', 'ileostomy', 'hernia', 'defect', 'closure', 'repair' and 'reconstruction' were used. Selection of studies and assessment of methodological quality were performed with a modified MINORS index. All reports on repair of parastomal hernias using a collagen-based biologic scaffold to reinforce or bridge the defect were included. Outcomes were recurrence rate, mortality and morbidity. RESULTS: Four retrospective studies with a combined enrolment of 57 patients were included. Recurrence occurred in 15.7% (95% confidence interval [CI] 7.8-25.9) of patients and wound-related complications in 26.2% (95% CI 14.7-39.5). No mortality or graft infections were reported. CONCLUSIONS: The use of reinforcing or bridging biologic grafts during parastomal hernia repair results in acceptable rates of recurrence and complications. However, given the similar rates of recurrence and complications achieved using synthetic mesh in this scenario, the evidence does not support use of biologic grafts

Evaluation and comparison of deoxyribonucleic acid typing methods on human tissue fixed with different fixatives

Abstract. Commonly employed fixing fluids result in very satisfactory histomorphologic analysis; however, they don't allow deoxyribonucleic acid (DNA) typing methods to provide good results. This study investigated the effect of eight fixatives on DNA extracted from placenta samples. Fresh tissue (placenta) specimens were fixed by immersion in different fixing fluids for different periods (from 24 h to 60 days). Different DNA extraction methods were assayed. Gene Amp 2400 and 9700 Thermal Cyclers coupled to AmpFLSTR Identifier kit (Applied Biosystems), that allows the simultaneous amplification of 15 STRs loci, was used for quantification. Amplified products were analyzed by capillary electrophoresis on ABI PRISM 310 and 3100 Genetic Analyzers (Applied Biosystems).

A case of HIV-associated progressive multifocal leukoencephalopathy: longitudinal studyof JCV NCCR arrangement in serial CSF samples

Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating disease of the brain caused by the JC virus (JCV). The viral genome contains a non-coding control region (NCCR) that regulates JCV replication. In the urine of healthy people NCCR has a linear arrangement designed as archetype (CY strain). In brain and cerebrospinal fluid (CSF) of PML patients NCCR shows deletions and enhancements. A 51-year-old black man with HIV-1 infection was admitted to our ward because of gait ataxia and dysarthria. Diagnosis of HIV infection was made in 2004; nadir of lymphocyte T CD4 (CD4) count was 4 cells/μl (1%); the patient experienced multiple treatment failures; HIV genotyping test showed a subtype B virus, with resistance mutations for PI, NRTI, NNRTI, INI and a CXCR4 tropism. Two months before the onset of symptoms a salvage treatment with boosted tipranavir, raltegravir, enfuvirtide, tenofovir/emtricitabine was started. At this time HIV-RNA was 2527 copies/ml and CD4 count was 9 cell/ μl (2%). After two months HIV-RNA was undetectable and CD4 count was 23 cells/ μl (3,8%). On admission physical examination showed a positive Romberg’s sign, gait ataxia, dysarthria and the Kurtzke Expanded Disability Status Scale (EDSS) score was 2,5. HIV-RNA was still undetectable, CD4 count was 18 cells/ μl (4%). Brain MRI showed multiple hyperintense white matter lesions on T2- weighted and fluid-attenuated inversion-recovery (FLAIR) imaging, in the temporal, cerebellar, ponto-bulbar regions. Diffusion-weighted imaging (DWI) showed signal hyperintensities. No contrast enhancement was seen. Real time polymerase chain reaction (Q-PCR) for JCV in the CSF was positive with a viral load of 16.700 gEq/mL. HIV-RNA in CSF was undetectable. Two weeks after admission motor function worsened and EDSS score was 6,5. A new MRI showed further extension of the lesions previously described, with cytotoxic edema. CSF examination was repeated, with JCVDNA viral load of 20.600 gEq/mL. An additional CSF sample was collected 4 weeks after admission, with JCV-DNA viral load of 26.000 gEq/mL. Patient showed high level of immune activation both in peripheral blood and CSF. Regarding the monitoring for JCV reactivation, at the time of first CSF sampling, the patient was negative for the viral load in plasma and urine. Concerning NCCR analysis, the viral variant archetype CY was found in CSF, in PBMCs and in the cells of the rectal swab. In the second and third CSF samples, the JCV NCCR analysis showed the presence of a rearranged sequence, with a duplication of the box C containing the binding site for the HIV-tat protein. In this case we observed a rearrangement of the JCV NCCR from the first to the second CSF sample, with a pattern suggestive for interactions between JCV and HIV-tat protein. Neurological deterioration coincided with JCV NCCR rearrangement

infezione da poliomavirus e carcinomi uroteliali:causa o effetto della trasformazione neoplastica?

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Prevalenza di HHV6,HHV7 ed HHV8 nel plasma di soggetti HIV positivi, sottoposti a ricerca mediante nested PCR: analisi delle correlazioni cliniche ed immuno-virologiche

HHV6, HHV7 e HHV8 sono virus erpetici ubiquitari che si contraggono durante l’infanzia e causano manifestazioni autolimitati.Correlazione tra infezione/riattivazione di HHV6 e HHV7 e l’insorgenza di patologie a carico del SNC (PML, SM), malattie autoimmuni e patologie ematologiche, prevalentemente in pz immunodepressi . Correlazione tra infezione da HHV8 ed insorgenza di sarcoma di Kaposi o linfomi in pz HIV+ . Tale studio è volto a determinare la prevalenza della positività al DNA di HHV6 HHV7 e HHV8 nel plasma di soggetti HIV + asintomatici, valutando le eventuali correlazioni cliniche e viro-immunologiche. I metodi utilizzati sono ricerca del DNA virale di HHV6,HHV7 e HHV8 nel plasma mediante nested PCR seguita da elettroforesi su gel di agarosio al 2% e colorazione del DNA con SYBR green e lettura del gel mediante transilluminazione con raggi U