Symptomatology and pathogenesis of different types of pain in multiple sclerosis

Multiple sclerosis (MS) is a progressive disease of the central nervous system. It is characterized by disseminated foci of demyelination, which are responsible for the diverse clinical picture of MS. Pain is a frequent but underestimated symptom of multiple sclerosis. It is estimated to affect 29–86% of MS patients in various stages of the disease and severely influences rehabilitation and quality of life. The pain experienced by MS patients is generally caused by nervous system damage during the course of the disease process and can usually be characterized as central neuropathic pain (less frequently as peripheral or nociceptive pain). The most frequent symptoms include dysesthetic extremity pain, painful tonic spasms, Lhermitte's sign, trigeminal neuralgia, headaches and low back pain. This paper discusses the probable mechanisms behind the development of pain in MS, the prevalence, classification, types of pain, as well as the most effective treatment methods

Recombinant Flag-tagged E1E2 glycoproteins from three hepatitis C virus genotypes are biologically functional and elicit cross-reactive neutralizing antibodies in mice

Hepatitis C virus (HCV) is a globally disseminated human pathogen for which no vaccine is currently available. HCV is highly diverse genetically and can be classified into 7 genotypes and multiple sub-types. Due to this antigenic variation, the induction of cross-reactive and at the same time neutralizing antibodies is a challenge in vaccine production. Here we report the analysis of immunogenicity of recombinant HCV envelope glycoproteins from genotypes 1a, 1b and 2a, with a Flag tag inserted in the hypervariable region 1 of E2. This modification did not affect protein expression or conformation or its capacity to bind the crucial virus entry factor, CD81. Importantly, in immunogenicity studies on mice, the purified E2-Flag mutants elicited high-titer, cross-reactive antibodies that were able to neutralize HCV infectious particles from two genotypes tested (1a and 2a). These findings indicate that E1E2-Flag envelope glycoproteins could be important immunogen candidates for vaccine aiming to induce broad HCV-neutralizing responses

Wybrane aspekty epidemiologiczne stwardnienia rozsianego w Polsce – wieloośrodkowe badanie pilotażowe

Background and purpose The aim was to conduct a pilot study of selected epidemiological aspects of multiple sclerosis (MS) in Poland. Material and methods Cross-sectional data were collected in 21 centres providing MS treatment. The demographic profile of the patients, medical history of MS, disability status, comorbidity, and diagnostic and treatment modalities were analysed. Results Data on 3581 patients were obtained, including 2494 women (69.6%) and 1030 men (28.8%) – sex ratio 2.4 : 1. The mean age was 40.7 ± 11.9 years. Monofocal onset was reported in 80.8% of cases – the most frequently reported location of lesions was supratentorial (36.1%), followed by optic nerves (26.5%) and spinal cord (20.1%). The mean disease duration was 10.2 ± 8.8 years (range 0.04–53 years), and the mean time from the first symptoms to MS diagnosis was 2.6 years. Relapsing-remitting MS was reported in 70.5% of patients, secondary progressive in 16.8%, primary progressive in 8.4%, and ‘benign MS’ in 2.5%. The mean EDSS score was 3.3 ± 2.2 (range 0–9.5). The family history of MS was positive in 6.4% of cases. Comorbidity mainly applied to the musculoskeletal system (6.5%), the urinary system (5.8%) and psychiatric disturbances (5.5%). Brain magnetic resonance studies were available in 96.3% of the patients, evoked potentials in 54%, and cerebrospinal fluid testing in 63.1% – of whom only 41.2% were tested for oligoclonal bands, with 84% of samples being positive. Immunomodulatory drugs were used in 842 patients (24%), predominandy interferon beta (81%) and glatiramer (13%). Mitoxantrone was the most commonly used immunosuppressant. Conclusions This project is the first countrywide large-scale MS survey, covering approximately 18% of patients, according to our estimates. The results identify the clinical condition of the patients, as well as diagnostic and treatment modalities.Wstęp i cel pracy Celem badania była pilotażowa analiza wybranych aspektów epidemiologicznych stwardnienia rozsianego (SR) w Polsce. Materiał i metody Przekrojowe dane zebrano w 21 ośrodkach prowadzących leczenie SR. Analizowano profil demograficzny chorych, wywiad chorobowy SR, stopień niepełnosprawności, choroby współwystępujące, metody diagnostyczne i stosowane leczenie. Wyniki Uzyskano dane 3581 pacjentów, w tym 2494 kobiet (69,6%) i 1030 mężczyzn (28,8%) – proporcja płci 2,4 : 1. Średni wiek wynosił 40,7 ± 11,9 roku. Początek jednoogniskowy odnotowano w 80,8% przypadków – najczęściej wskazywano na nadnamiotową lokalizację uszkodzeń (36,1%), w dalszej kolejności zajęte były nerwy wzrokowe (26,5%) i rdzeń kręgowy (20,1%). Choroba trwała średnio 10,2 ± 8,8 roku (zakres 0,04–53 lat), a od pierwszych objawów do ustalenia rozpoznania mijało średnio 2,6 roku. Postać nawra-cająco-zwalniającą SR miało 70,5% chorych, wtórnie postępującą – 16,8%, pierwotnie postępującą – 8,4%, u 2,5% rozpoznano zaś „łagodne” SR. Średni stopień niesprawności w skali EDSS wyniósł 3,3 ±2,2 (zakres 0–9,5). Rodzinne występowanie SR odnotowano w 6,4% przypadków. Wśród chorób współwystępujących najczęstsze były schorzenia narządu ruchu (6,5%), układu moczowego (5,8%) i zaburzenia psychiczne (5,5%). Rezonans magnetyczny mózgu wykonano u 96,3% pacjentów, potencjały wywołane u 54%, badanie płynu mózgowo-rdzeniowego u 63,1% – z czego zaledwie w 41,2% przypadków oznaczano prążki oligoklonalne (ich obecność stwierdzono w 84% próbek). Leki immunomodulujące otrzymywało 842 chorych (24%), najczęściej były to interferon β (81%) i glatiramer (13%). W immunosupresji najczęściej stosowano mitoksantron. Wnioski Zrealizowany projekt jest pierwszym ogólnopolskim badaniem populacji chorych na SR na tak szeroką skalę – wg naszych szacunków obejmującym ok. 18% populacji chorych. Zgromadzone wyniki informują o stanie klinicznym chorych, najczęstszych metodach diagnostyki i leczenia

Peripheral and central compensatory mechanisms for impaired vagus nerve function during peripheral immune activation

Background Determining the etiology and possible treatment strategies for numerous diseases requires a comprehensive understanding of compensatory mechanisms in physiological systems. The vagus nerve acts as a key interface between the brain and the peripheral internal organs. We set out to identify mechanisms compensating for a lack of neuronal communication between the immune and the central nervous system (CNS) during infection. Methods We assessed biochemical and central neurotransmitter changes resulting from subdiaphragmatic vagotomy and whether they are modulated by intraperitoneal infection. We performed a series of subdiaphragmatic vagotomy or sham operations on male Wistar rats. Next, after full, 30-day recovery period, they were randomly assigned to receive an injection of Escherichia coli lipopolysaccharide or saline. Two hours later, animal were euthanized and we measured the plasma concentration of prostaglandin E2 (with HPLC-MS), interleukin-6 (ELISA), and corticosterone (RIA). We also had measured the concentration of monoaminergic neurotransmitters and their metabolites in the amygdala, brainstem, hippocampus, hypothalamus, motor cortex, periaqueductal gray, and prefrontal medial cortex using RP-HPLC-ED. A subset of the animals was evaluated in the elevated plus maze test immediately before euthanization. Results The lack of immunosensory signaling of the vagus nerve stimulated increased activity of discrete inflammatory marker signals, which we confirmed by quantifying biochemical changes in blood plasma. Behavioral results, although preliminary, support the observed biochemical alterations. Many of the neurotransmitter changes observed after vagotomy indicated that the vagus nerve influences the activity of many brain areas involved in control of immune response and sickness behavior. Our studies show that these changes are largely eliminated during experimental infection. Conclusions Our results suggest that in vagotomized animals with blocked CNS, communication may transmit via a pathway independent of the vagus nerve to permit restoration of CNS activity for peripheral inflammation control

Comprehensive linker-scanning mutagenesis of the hepatitis C virus E1 and E2 envelope glycoproteins reveals new structure–function relationships

Despite extensive research, many details about the structure and functions of hepatitis C virus (HCV) glycoproteins E1 and E2 are not fully understood, and their crystal structure remains to be determined. We applied linker-scanning mutagenesis to generate a panel of 34 mutants, each containing an insertion of 5 aa at a random position within the E1E2 sequence. The mutated glycoproteins were analysed by using a range of assays to identify regions critical for maintaining protein conformation, E1E2 complex assembly, CD81 receptor binding, membrane fusion and infectivity. The results, while supporting previously published data, provide several interesting new findings. Firstly, insertion at amino acid 587 or 596 reduced E1E2 heterodimerization without affecting reactivity with some conformation-sensitive mAbs or with CD81, thus implicating these residues in glycoprotein assembly. Secondly, insertions within a conserved region of E2, between amino acid residues 611 and 631, severely disrupted protein conformation and abrogated binding of all conformation-sensitive antibodies, suggesting that the structural integrity of this region is critical for the correct folding of E2. Thirdly, an insertion at Leu-682 specifically affected membrane fusion, providing direct evidence that the membrane-proximal ‘stem’ of E2 is involved in the fusion mechanism. Overall, our results show that the HCV glycoproteins generally do not tolerate insertions and that there are a very limited number of sites that can be changed without dramatic loss of function. Nevertheless, we identified two E2 insertion mutants, at amino acid residues 408 and 577, that were infectious in the murine leukemia virus-based HCV pseudoparticle system

Varicellovirus UL 49.5 proteins differentially affect the function of the transporter associated with antigen processing, TAP

Cytotoxic T-lymphocytes play an important role in the protection against viral infections, which they detect through the recognition of virus-derived peptides, presented in the context of MHC class I molecules at the surface of the infected cell. The transporter associated with antigen processing (TAP) plays an essential role in MHC class I–restricted antigen presentation, as TAP imports peptides into the ER, where peptide loading of MHC class I molecules takes place. In this study, the UL49.5 proteins of the varicelloviruses bovine herpesvirus 1 (BHV-1), pseudorabies virus (PRV), and equine herpesvirus 1 and 4 (EHV-1 and EHV-4) are characterized as members of a novel class of viral immune evasion proteins. These UL49.5 proteins interfere with MHC class I antigen presentation by blocking the supply of antigenic peptides through inhibition of TAP. BHV-1, PRV, and EHV-1 recombinant viruses lacking UL49.5 no longer interfere with peptide transport. Combined with the observation that the individually expressed UL49.5 proteins block TAP as well, these data indicate that UL49.5 is the viral factor that is both necessary and sufficient to abolish TAP function during productive infection by these viruses. The mechanisms through which the UL49.5 proteins of BHV-1, PRV, EHV-1, and EHV-4 block TAP exhibit surprising diversity. BHV-1 UL49.5 targets TAP for proteasomal degradation, whereas EHV-1 and EHV-4 UL49.5 interfere with the binding of ATP to TAP. In contrast, TAP stability and ATP recruitment are not affected by PRV UL49.5, although it has the capacity to arrest the peptide transporter in a translocation-incompetent state, a property shared with the BHV-1 and EHV-1 UL49.5. Taken together, these results classify the UL49.5 gene products of BHV-1, PRV, EHV-1, and EHV-4 as members of a novel family of viral immune evasion proteins, inhibiting TAP through a variety of mechanisms

The effect of glycan shift on antibodies against HCV E2 412-425 epitope elicited by chimeric sHBsAg-based virus-like particles

Two of the most important mechanisms of hepatitis C virus (HCV) immune evasion are the high variability of the amino acid sequence and epitope shielding via heavy glycosylation of the envelope (E) proteins. Previously, we showed that chimeric sHBsAg (hepatitis B virus [HBV] small surface antigen)-based virus-like particles (VLPs) carrying highly conserved epitope I from the HCV E2 glycoprotein (sHBsAg_412–425) elicit broadly neutralizing antibodies (bnAbs). However, many reports have identified escape mutations for such bnAbs that shift the N-glycosylation site from N417 to N415. This shift effectively masks the recognition of epitope I by antibodies raised against the wild-type glycoprotein. To investigate if glycan-shift-mediated immune evasion could be overcome by targeted vaccination strategies, we designed sHBsAg-based VLPs carrying epitope I with an N417S change (sHBsAg_N417S). Studies in BALB/c mice revealed that both sHBsAg_412–425 and sHBsAg_N417S VLPs were immunogenic, eliciting antibodies that recognized peptides encompassing epitope I regardless of the N417S change. However, we observed substantial differences in E1E2 glycoprotein binding and cell culture-derived HCV (HCVcc) neutralization between the sera elicited by sHBsAg_412–425 and those elicited by sHBsAg_N417S VLPs. Our results suggest a complex interplay among antibodies targeting epitope I, the E1E2 glycosylation status, and the epitope or global E1E2 conformation. Additionally, we observed striking similarities in the E1E2 glycoprotein binding patterns and HCVcc neutralization between sHBsAg_412–425 sera and AP33, suggesting that the immunization of mice with sHBsAg_412–425 VLPs can elicit AP33-like antibodies. This study emphasizes the role of antibodies against epitope I and represents an initial effort toward designing an antigen that elicits an immune response against epitope I with a glycan shift change

Decreased Doublecortin (DCX) immunoreactivity in hippocampus after profound sensorineural hearing loss and vestibular dysfunction in adult mice

Objective: sensorineural hearing loss (SNHL) and bilateral vestibulopathy (BV) have been associated with cognitive decline and incident dementia. Our aim was to investigate the combined effect of profound SNHL and BV on spatial cognition and hippocampal neurogenesis in adult mice. Methods: Single oral intake of allylnitrile produces otovestibular failure in less than a week. Behavioral assessment included recording of spontaneous activity, motor activity, spatial cognition, etc. Evaluation of hippocampal neurogenesis was performed 8 weeks after treatment by quantification of neural precursor cells and proliferating cells in the dentate gyrus by staining with doublecortin (Dcx) and Ki67, respectively. Results: Profound SNHL and BV were confirmed in the allylnitrile-treated mice respectively by means of auditory brainstem response (ABR) and acoustic startle response, and several vestibular tests. Spatial cognitive deficits, i.e. higher latency to target, were observed with the Barnes maze. In the right hemisphere, no statistically significant difference was observed between groups. In the left hemisphere, the difference in mean cell densities of Dcx positive cells was statistically significant when compared to the control group, whereas the difference in mean cell density of Ki67 positive cells did not differ significantly. Conclusion: Spatial cognitive deficits and decreased immunoreactivity to DCX in the left hippocampus were observed 8 weeks after adult mice acquired profound SNHL and BV

The use of spa and phage typing for characterization of clinical isolates of methicillin-resistant Staphylococcus aureus in the University Clinical Center in Gdańsk, Poland

The emergence of spa types and spa–clonal complexes (CC) among clinical methicillin-resistant Staphylococcus aureus isolates collected from the University Clinical Center in Gdańsk between 2008 and 2009 were investigated. Phage typing was used as the initial screening in the study. The basic set of phages and the additional set of phages were used. Most of the isolates (56 %) belonged to the phage group III. With the additional set of phages, eight types were found, with predominant one MR8 (50 %). Sixteen distinct spa types were observed. The most frequent were t003 (22 %), t151 (16 %), and t008 (12 %). The spa types were clustered into two spa-CC and eight singletons. The predominant CC010 (50 %) consisted of six types, with the most common t003 (36.7 %) and t151(26.7 %), and in 80 % was identified as staphylococcal chromosomal casette mec (SCCmec) type II. The second cluster has no founder (12 %) with only two spa types: t037 belonging to SCCmec type III and t029. In the most frequent singleton, spa type t008 alone was clustered in 12 % of the isolates. All singletons correspond to SCCmec type IV. The CC010 was distributed in most of the hospital wards, corresponded to Multilocus sequence typing type ST5/ST225 and was constantly present throughout the observed period. The isolates of CC010 generally belonged to the phage group III, and most of them (53.3 %) were resistant to erythromycin, clindamycin, and ciprofloxacin. The concordance between spa-clone and phage type was very high, but the same phage type MR8 was observed within different spa types of the predominant clone