Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
3,576 result(s) for "Complement System Proteins - immunology"
Sort by:
Randomized trial showing persistence of hSBA titers elicited by a pentavalent meningococcal MenABCWY vaccine for up to 4 years following a primary series and safety and immunogenicity of a booster dose
Vaccination against 5 prominent meningococcal serogroups (A/B/C/W/Y) is necessary for broad disease protection. We report immunopersistence through 4 years after a 2-dose (6-month interval) pentavalent MenABCWY primary vaccine series and safety and immunogenicity of a booster administered 4 years after primary vaccination. This randomized, active-controlled, observer-blinded study was conducted in the United States and Europe. In stage 1, healthy MenACWY vaccine-naive or -experienced 10- to 25-year-olds were randomized 1:2 to receive MenABCWY and placebo or MenB-fHbp and MenACWY-CRM. Eligible participants were randomly selected to participate in stage 2, which was an open-label immunopersistence and booster extension. Immunogenicity was assessed through serum bactericidal antibody using human complement (hSBA) assays with serogroups A/C/W/Y (MenA/C/W/Y) and 4 primary serogroup B (MenB) test strains. Immunogenicity endpoints included hSBA seroprotection rates through 48 months after primary vaccination and 1 month after the booster. Safety endpoints included booster reactogenicity events and adverse events (AEs). Of 1379 eligible participants, 353 entered stage 2; 242 completed the 48-month blood draw after primary vaccination and 240 completed the booster vaccination phase. MenA/C/W/Y seroprotection rates remained high for 4 years following a 2-dose MenABCWY primary series (MenACWY-naive, 62.0 %–100.0 %; MenACWY-experienced, 98.7 %–100.0 %) and trended higher than those after a single MenACWY-CRM dose (MenACWY-naive, 38.1 %–95.2 %; MenACWY-experienced, 89.7 %–100.0 %). Corresponding seroprotection rates against MenB remained stable and generally higher than baseline (MenABCWY, 18.2 %–36.6 %; MenB-fHbp, 16.2 %–31.9 % across strains). Following a booster, seroprotection rates against all 5 serogroups were ≥ 93.8 % across groups. Most booster dose reactogenicity events were mild or moderate in severity, and AEs were infrequent. Immune responses remained high for MenA/C/W/Y and above baseline for MenB through 4 years after the MenABCWY primary series, with robust responses for all 5 serogroups observed following a booster. The MenABCWY booster had an acceptable safety and tolerability profile consistent with the primary series. NCT03135834. •Broad protection against meningococcal disease requires serogroup ABCWY vaccination•Immunopersistence up to 4y post MenABCWY primary and booster responses are reported•Seroprotection stayed high (ACWY) and largely >baseline (B) for 4y postvaccination•A MenABCWY booster at 4y induced anamnestic immune responses for all 5 serogroups•The booster had acceptable safety and tolerability, similar to the primary series
A bivalent Neisseria meningitidis recombinant lipidated factor H binding protein vaccine in young adults: Results of a randomised, controlled, dose-escalation phase 1 trial
► A first-in-human study of a bivalent rLP2086 N. meningitidis serogroup B vaccine. ► Healthy adults received placebo or ascending dose levels of bivalent rLP2086. ► Bivalent rLP2086 induced robust serum bactericidal activity against 6 diverse MnB strains. ► Most recipients (75–100%) of 60μg or 200μg doses had seroprotective (≥1:4) hSBA titres. ► The vaccine was well tolerated; adverse events were rare and generally mild or moderate. Neisseria meningitidis is a leading cause of meningitis and septicaemia, but a broadly-protective vaccine against endemic serogroup B disease is not licensed and available. The conserved, outer-membrane lipoprotein factor H binding protein (fHBP, also known as LP2086) is expressed as one of two subfamily variants in virtually all meningococci. This study investigated the safety, tolerability, and immunogenicity of a recombinant-expressed bivalent fHBP (r-fHBP) vaccine in healthy adults. Participants (N=103) aged 18–25 years were recruited into three ascending dose level cohorts of 20, 60, and 200μg of a bivalent r-fHBP vaccine formulation and randomised to receive vaccine or placebo at 0, 1, and 6 months. The vaccine was well tolerated. Geometric mean titres (GMTs) for r-fHBP subfamily-specific IgG antibodies increased 19–168-fold from pre-vaccination to post-dose 2 in a dose level-dependent manner. In addition, robust serum bactericidal assay using human complement (hSBA) responses for strains expressing both homologous and heterologous fHBP variants were observed. After three vaccinations, 16–52% of the placebo group and 47–90%, 75–100%, and 88–100%, of the 20, 60, and 200μg dose levels, respectively, had seroprotective (≥1:4) hSBA titres against six serogroup B strains. The bivalent r-fHBP vaccine was well tolerated and induced robust bactericidal activity against six diverse serogroup B strains in young adults at the 60 and 200μg dose levels.
Phase III Comparison of an Investigational Quadrivalent Meningococcal Conjugate Vaccine with the Licensed Meningococcal ACWY Conjugate Vaccine in Adolescents
Background. Neisseria meningitidis is an important cause of invasive bacterial infection in the United States, and disease rates are higher for adolescents than for the general population. Quadrivalent meningococcal conjugate vaccine is recommended for routine vaccination of adolescents and high-risk groups. This study compares the safety and immunogenicity of the Novartis Vaccines investigational quadrivalent meningococcal CRM197conjugate vaccine, MenACWY-CRM, with the licensed meningococcal conjugate vaccine, Menactra. Methods. In this multicenter phase III study, 2180 adolescents 11–18 years of age were randomly assigned to 4 groups (1:1:1:1) to receive a single dose of 1 of 3 lots of MenACWY-CRM or a single dose of Menactra. Serum samples obtained before vaccination and 1 month after vaccination were tested for serogroup-specific serum bactericidal activity using human complement (hSBA). The hSBA titers after vaccination with MenACWY-CRM or Menactra were compared in noninferiority and superiority analyses. Results. The hSBA geometric mean titers after MenACWY-CRM vaccination were higher than the hSBA geometric mean titers after Menactra vaccination, and criteria for superiority were met for this end point for all 4 serogroups. Also, the criteria for superiority of MenACWY-CRM, compared with Menactra, were met for the end points of proportion of subjects with postvaccination hSBA titers ⩾1:8 and proportion of seroresponders for serogroups A, W-135, and Y. MenACWY-CRM was noninferior to Menactra for serogroup C for these end points. Reactogenicity was similar, with 64% of the MenACWY-CRM recipients and 70% of the Menactra recipients reporting mild and/or moderate solicited reactions. Neither vaccine was associated with a serious adverse event. Conclusions. MenACWY-CRM vaccine is well tolerated in adolescents and generates a stronger immune response than Menactra for all 4 serogroups. Trial registration. Clinicaltrials.gov identifier: NCT00450437.
Therapeutic antitumor efficacy of monoclonal antibody against Claudin-4 for pancreatic and ovarian cancers
Claudin‐4 (CLDN4) is a tetraspanin transmembrane protein of tight junction structure and is highly expressed in pancreatic and ovarian cancers. In this study, we aimed to generate an anti‐Claudin‐4 monoclonal antibody (mAb) and evaluate its antitumor efficacy in vitro and in vivo. To isolate specific mAb, we generated CLDN3, 4, 5, 6, and 9, expressing Chinese hamster ovary (CHO) cells, and then used them as positive and negative targets through cell‐based screening. As a result, we succeeded in isolating KM3900 (IgG2a), which specifically bound to CLDN4, from BXSB mice immunized with pancreatic cancer cells. Immunoprecipitation and flow cytometry analysis revealed that KM3900 recognized the conformational structure and bound to extracellular loop 2 of CLDN4. Furthermore, binding of KM3900 was detected on CLDN4‐expressing pancreatic and ovarian cancer cells, but not on negative cells. Next, we made the mouse–human chimeric IgG1 (KM3934) and evaluated its antitumor efficacy. KM3934 induced dose‐dependent antibody‐dependent cellular cytotoxicity and complement‐dependent cytotoxicity in vitro, and significantly inhibited tumor growth in MCAS or CFPAC‐1 xenograft SCID mice in vivo (P < 0.05). These results suggest that mAb therapy against CLDN4 is promising for pancreatic and ovarian cancers. (Cancer Sci 2009; 100: 1623–1630)
Novel mechanisms and functions of complement
Lambris and colleagues discuss new and previously unanticipated functions of complement and how these affect immunity and disease pathogenesis. Progress at the beginning of the 21st century transformed the perception of complement from that of a blood-based antimicrobial system to that of a global regulator of immunity and tissue homeostasis. More recent years have witnessed remarkable advances in structure–function insights and understanding of the mechanisms and locations of complement activation, which have added new layers of complexity to the biology of complement. This complexity is readily reflected by the multifaceted and contextual involvement of complement-driven networks in a wide range of inflammatory and neurodegenerative disorders and cancer. This Review provides an updated view of new and previously unanticipated functions of complement and how these affect immunity and disease pathogenesis.
Complement in neurological disorders and emerging complement-targeted therapeutics
The complement system consists of a network of plasma and membrane proteins that modulate tissue homeostasis and contribute to immune surveillance by interacting with the innate and adaptive immune systems. Dysregulation, impairment or inadvertent activation of complement components contribute to the pathogenesis of some autoimmune neurological disorders and could even contribute to neurodegenerative diseases. In this Review, we summarize current knowledge about the main functions of the complement pathways and the involvement of complement in neurological disorders. We describe the complex network of complement proteins that target muscle, the neuromuscular junction, peripheral nerves, the spinal cord or the brain and discuss the autoimmune mechanisms of complement-mediated myopathies, myasthenia, peripheral neuropathies, neuromyelitis and other CNS disorders. We also consider the emerging role of complement in some neurodegenerative diseases, such as Alzheimer disease, amyotrophic lateral sclerosis and even schizophrenia. Finally, we provide an overview of the latest complement-targeted immunotherapies including monoclonal antibodies, fusion proteins and peptidomimetics that have been approved, that are undergoing phase I–III clinical trials or that show promise for the treatment of neurological conditions that respond poorly to existing immunotherapies.In this Review, Dalakas et al. discuss the complement system, the role it plays in autoimmune neurological disease and neurodegenerative disease, and provide an overview of the latest therapeutics that target complement and that can be used for or have potential in neurological disorders.
Antibody persistence 5 years after vaccination at 2 to 10 years of age with Quadrivalent MenACWY-CRM conjugate vaccine, and responses to a booster vaccination
•We assessed persistence 5 years after vaccinating 2–10 years-olds with MenACWY-CRM (84).•hSBA titers against serogroups CWY persisted for 5 years after MenACWY-CRM vaccine (85).•Revaccination elicited booster responses to all serogroups 5 years after priming (82).•Robust immune responses were observed after primary vaccination in 7–15 years-olds (84).•All vaccinations were generally well-tolerated with no safety concern raised (78). In a multi-center extension study, children 2–10 years of age, initially vaccinated with one or two doses (2–5 year-olds) or one dose (6–10 year-olds) of quadrivalent meningococcal CRM197-conjugate vaccine (MenACWY-CRM), were assessed five years later for antibody persistence and booster response using serum bactericidal assay with human complement (hSBA). Children 7–10 and 11–15 years of age, who received MenACWY-CRM in the original study, and age-matched vaccine-naïve children, were enrolled in this extension study. After an initial blood draw, children received one dose of MenACWY-CRM as booster or primary dose, with a second blood draw 28 days later. hSBA titers decreased five years after primary vaccination, but were higher than in non-vaccinated controls against serogroups C, W and Y, with substantial proportions having titers ≥8: 7–22% for A, 32–57% for C, 74–83% for W, and 48–54% for Y. Previously-vaccinated children demonstrated booster responses to revaccination against all four serogroups. Responses to primary vaccination in vaccine-naïve controls were lower and similar to primary responses observed in the original study. All vaccinations were generally well tolerated, with no safety concern raised. Approximately half the children vaccinated as 2–10 year-olds maintained protective antibodies against serogroups C, W and Y five years later, but fewer did against serogroup A. Declining titers five years after vaccination and robust booster responses suggest that five years may be an appropriate interval to revaccinate children, subject to epidemiology and delivery considerations.
Safety and immunogenicity of a CRM or TT conjugated meningococcal vaccine in healthy toddlers
MenACWY-CRM (Menveo®; GlaxoSmithKline) and MenACWY-TT (Nimenrix®; Pfizer) are two meningococcal vaccines licensed in the European Union for use in both children and adults. While both vaccines target meningococcal serogroups A, C, W and Y, immunogenicity and reactogenicity of these quadrivalent meningococcal conjugate vaccines may differ due to differences in formulation processes and chemical structure. Yet data on the comparability of these two vaccines are limited. The reactogenicity and immunogenicity of one dose of either MenACWY-CRM or MenACWY-TT were evaluated in healthy toddlers aged 12–15 months. Immunogenicity was assessed using serum bactericidal antibody assays (SBA) with human (hSBA) and rabbit (rSBA) complement. A total of 202 children aged 12–15 months were enrolled to receive one dose of MenACWY-CRM or MenACWY-TT. Similar numbers of subjects reported solicited reactions within 7 days following either vaccination. Tenderness at the injection site was the most common local reaction. Systemic reactions reported were similar for both vaccines and mostly mild to moderate in severity: irritability, sleepiness and change in eating habits were most commonly reported. Immunogenicity at 1 month post-vaccination was generally comparable for both vaccines across serogroups. At 6 months post-vaccination antibody persistence against serogroups C, W, and Y was substantial for both vaccines, as measured by both assay methodologies. For serogroup A, hSBA titers declined in both groups, while rSBA titers remained high. Despite differences in composition, the MenACWY-CRM and MenACWY-TT vaccines have comparable reactogenicity and immunogenicity profiles. Immediate immune responses and short-term antibody persistence were largely similar between groups. Both vaccines were well-tolerated and no safety concerns were identified.
Depletion of complement system immunity in patients with myocardial infarction
The aim of the present study was to evaluate differences in the expression of complement system genes, and serum levels of CH50, C3 and C4 in peripheral blood mononuclear cells from patients with myocardial infarction (AMI), stable angina pectoris (SA) and controls. A total of 100 patients with AMI, 100 with SA and 100 clinical controls were recruited in the present study. In each group, 20 randomly selected individuals were examined using whole human genome microarray analysis to detect the expression of genes of the complement system. The serum levels of CH50, C3 and C4 were measured in all 300 subjects. In the patients with AMI, the expression levels of genes encoding C1qα, C1qβ, C1qγ, C1r, Factor P, C5a (complement component), CR1, integrin αM, integrin αX, integrin β2, C5aR, CRIg (complement receptors) and CD46, CD55 and CD59 (complement regulators) were significantly higher, compared with the respective genes in the SA patients and controls (P<0.05), whereas the mRNA levels of C1s, C7, C8β and C9 were the lowest in this group (P<0.05). No statistically significant differences were found in the gene expression levels of complement components or regulators between the SA and control groups. The serum levels of CH50, C3 and C4 were significantly increased in the AMI and SA groups, compared with the controls. In the AMI and SA groups, the complement system was activated. However, the differential mRNA expression of complement components, receptors and regulators in the AMI group suggested the dysfunction of the C5b-9 complex. The depression of complement system immunity in the patients with AMI may be associated with the pathogenesis of AMI.
Immunogenicity and safety of a multicomponent meningococcal serogroup B vaccine in healthy adolescents in Korea—A randomised trial
Neisseria meningitidis serogroup B is a significant cause of septicaemia and meningitis worldwide. This phase 3 randomised, controlled study assessed the immunogenicity and safety of a multicomponent meningococcal serogroup B vaccine, 4CMenB, in healthy Korean adolescents. 264 adolescents (11–17 years old) were randomised to receive two doses, one month apart, of 4CMenB or control vaccines [placebo followed by one dose of a quadrivalent meningococcal ACWY glycoconjugate vaccine (MenACWY-CRM)]. Immunogenicity was evaluated by serum bactericidal assay with human complement (hSBA) against three serogroup B test strains specific for individual vaccine antigens (fHbp, NadA or PorA P1.4), and by enzyme-linked immunosorbent assay (ELISA) against the NHBA antigen. Solicited reactions and adverse events (AEs) were assessed. One month post-second vaccination, 98%, 97%, and 97% of subjects in the 4CMenB group achieved hSBA titres ≥4 against the fHbp, NadA and PorA test strains, respectively, while percentages in the Control group were comparable to baseline (27%, 16%, and 17%, respectively). Geometric mean ELISA concentrations (GMCs) against NHBA increased 52-fold relative to baseline in the 4CMenB group, while there was no substantial increase in GMCs in the Control group (1.05-fold). Frequencies of solicited reactions after any vaccination were higher in the 4CMenB group than in the Control group, although most reactions were of short duration and mild to moderate intensity. There were no vaccine-related serious AEs. Two doses of 4CMenB induced robust immune responses against the vaccine antigens and were well tolerated, with no safety concerns identified, in Korean adolescents (NCT01973218).