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Economic aspects of established antibodies and recently available therapies

Immunotherapies within the German healthcare system : Economic aspects of established antibodies and recently available therapies

 

In the German healthcare system, immunotherapies have been effectively established for years. Currently there are over 100 registrations of monoclonal antibodies (MABs). In current years, new immunotherapeutic approaches turned available, amongst them checkpoint inhibitors and CAR‑T cells in oncology. Increasing expenditures of the German statutory medical health insurance (SHI) system are regarded with issues.

This article presents an summary of the event and standing of prescriptions and gross sales of chosen immunotherapeutics in Germany. Data from 2015-2019 had been analyzed, primarily from the GKV-Arzneimittel-Schnellinformation (GAmSi) and the consultancy IQVIA.In the group of older MABs, corresponding to immunosuppressive and antineoplastic brokers, biosimilars led to a (non permanent) enhance of functions, however reimbursement quantities are lowering.

Instruments of the SHI system like drug agreements, reference costs, and particular person low cost contracts intervene as expenditure management. Checkpoint inhibitors clearly present rising prescriptions and expenditures. Finally, the CAR‑T cells are certainly very costly therapies, however are at the moment not that necessary as a result of restricted quantity of functions. In addition, the exemption from VAT of 19% and the signed low cost agreements between suppliers and illness funds scale back the burden.

In 2015 and 2019, the web expenditures on medicine and surgical dressings accounted for 17.2% of the whole expenditures on advantages of the SHI system. Should the expenditures on medicine enhance overproportionately sooner or later, the German SHI system will be capable to counteract with already available or new devices, supported by the legislator. Manufacturers and the SHI system ought to develop joint actions to realize options for brand new remedy approaches.

 

Analysis of Tumor Depth Invasion With Anti-Smoothelin Antibody in Equivocal Transurethral Resection of Urinary Bladder Tumor Surgical Specimens

 

Objective: To look at the expression and worth of the smoothelin marker in management circumstances, to standardize the working technique, and to investigate its software in pathologic staging course of of problematic transurethral resection of bladder tumor (TURBT) circumstances.

 

Material and strategies: Immunohistochemical (IHC) staining was carried out on tumor-free bladder wall sections, tumor-free giant bowel sections, TURBTs with unequivocal tumor stage, and TURBTs with equivocal stage. The IHC staining of muscularis mucosa (MM), muscularis propria (MP), and blood vessels was evaluated semiquantitatively.

 

Results: Smoothelin IHC staining sample ranged from unfavourable (30% to 67% circumstances) to 2+ (0% to 15% circumstances) in MM and from 1+ (10% to 50% circumstances) to three+ (9% to 48% circumstances) in MP. When in contrast on the identical slide, the smoothelin expression of MP confirmed a stronger staining depth than the one of the MM in all of the analyzed circumstances. Blood vessel muscle cells stained in a relentless depth because the MM (r = 0.9808; r = 0.9604). Smoothelin decided restaging of 33% of the problematic TURBT circumstances.

 

Conclusion: Smoothelin is an IHC marker that reveals differential staining between coexistent MM and MP; nevertheless, variations in staining depth and sample might happen, aspects that may be influenced by completely different method variables. We suggest utilizing this marker as a diagnostic instrument in problematic TURBT circumstances solely when there may be adequate expertise in management circumstances with this antibody.

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Characterization of New Monoclonal PF4-Specific Antibodies as Useful Tools for Studies on Typical and Autoimmune Heparin-Induced Thrombocytopenia

 

Background: Heparin-induced thrombocytopenia (HIT) is usually brought on by platelet-activating immunoglobulin G (IgG) antibodies (Abs) towards platelet issue 4 (PF4) complexed with heparin (H). Much much less frequent “autoimmune” HIT is distinguished from typical HIT by platelet activation with out heparin and the presence of each anti-PF4/H and anti-PF4 IgG. We developed three murine monoclonal anti-PF4 Abs with a human Fc-part, 1E12, 1C12, and 2E1, resembling autoimmune HIT Abs.

 

Objectives: To characterize 1E12, 1C12, and 2E1 compared to the heparin-dependent monoclonal anti-PF4/H Abs 5B9 and KKO, and polyclonal Abs from sufferers with typical HIT (group-2) and autoimmune HIT (group-3).

 

Methods: Interactions of Abs with PF4 and PF4/H had been studied by enzyme-linked-immunosorbent assay, single-molecule drive spectroscopy, isothermal titration calorimetry, and dynamic gentle scattering. Serotonin launch assay and heparin-induced platelet activation assay had been used to evaluate platelet activation. The binding websites of monoclonal Abs on PF4 had been predicted in silico (MAbTope technique).

 

Results: 1C12, 1E12, and 2E1 displayed larger affinity for PF4/H complexes than 5B9 and KKO, akin to human group-3 Abs. Only 1C12, 1E12, 2E1, and group-3 Abs fashioned giant complexes with native PF4, and activated platelets with out heparin. The predicted binding websites of 1C12, 1E12, and 2E1 on PF4 differed from these of KKO and 5B9, however had been shut to one another. 2E1 exhibited distinctive bivalent binding, involving its antigen recognition web site to PF4 and charge-dependent interactions with heparin.

 

Antibodies towards human neutrophil antigens in non-transfused girls with purple blood cell alloimmunisation induced by being pregnant

 

Background: Alloantibodies towards human neutrophil antigens (HNA) ensuing from allogeneic publicity could also be related to transfusion-related acute lung harm and immune neutropenia. Understanding the danger components for the formation of such antibodies may have an incredible affect on the adoption of measures to forestall probably deadly transfusion reactions. The purpose of the research was to find out the prevalence of anti-HNA alloantibodies in non-transfused pregnant girls with and with out purple blood cell (RBC) alloantibodies.

 

Materials and strategies: HNA alloantibodies had been investigated in blood samples from 147 pregnant girls with RBC alloimmunisation induced by being pregnant as the one allogeneic stimulus (group 1). The management group (group 2) consisted of 563 girls with not less than one being pregnant with out RBC alloimmunisation. Both teams had been investigated for the presence and id of HNA alloantibodies utilizing granulocyte agglutination checks, white blood cell immunofluorescence testing, and the bead-based LABScreen Multi Kit. Genotyping was carried out to verify the specificity of the HNA alloantibodies.

 

Results: Group 1 girls had a statistically larger quantity of HNA alloantibodies in comparison with group 2 girls (9/147 [6.1%] vs 9/563 [1.6%]; p=0.005, OR=4.01; 95% CI 1.5-10.3). Considering solely multiparous girls, there was the next statistical significance for the distinction within the presence of HNA alloantibodies between the 2 teams (7/82 [8.5%] vs 9/493 [1.8%]; p=0.002, OR=5.02; 95% CI 1.8-13.9).

 

Characterization of G-quadruplex antibody reveals differential specificity for G4 DNA varieties

 

  • Accumulating proof means that human genome can fold into non-B DNA buildings, when applicable sequence and beneficial situations are current. Among these, G-quadruplexes (G4-DNA) are related to gene regulation, chromosome fragility and telomere upkeep. Although a number of strategies are utilized in detecting such buildings in vitro, understanding their intracellular existence has been difficult.
  • Recently, an antibody, BG4, was described to check G4-structures inside cells. Here, we characterize BG4 for its affinity in direction of G4-DNA, utilizing a number of biochemical and biophysical instruments. BG4 certain to G-rich DNA derived from a number of genes that type G-quadruplexes, not like complementary C-rich or random sequences. BLI research revealed sturdy binding affinity (Kd = 17.Four nM).
  • Gel shift assays present BG4 binds to inter and intramolecular G4-DNA, when it’s in parallel orientation. Mere presence of G4-motif in duplex DNA is inadequate for antibody recognition. Importantly, BG4 can bind to G4-DNA inside telomere sequence in a supercoiled plasmid. Finally, we present that BG4 binds to type environment friendly foci in 4 cell traces, irrespective of their lineage, demonstrating presence of G4-DNA in genome.
  • Importantly, quantity of BG4 foci inside the cells could be modulated, upon knockdown of G4-resolvase, WRN. Thus, we set up specificity of BG4 in direction of G4-DNA and talk about its potential functions.

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Impact of Immune Priming, Vaccination and Infection on Influenza A

Impact of Immune Priming, Vaccination and Infection on Influenza A(H3N2) Antibody Landscapes in Children

Background: Pre-existing antibodies to influenza, formed by early an infection and subsequent exposures, might affect responses to influenza vaccination.

Methods: We enrolled 72 youngsters (7-17 years) in 2015-16, all obtained inactivated influenza vaccines. Forty-one have been additionally vaccinated in 2014-15 with 12 grew to become contaminated with A(H3N2) in 2014-15. Thirty-one youngsters didn’t have documented influenza exposures within the prior 5 seasons. Sera have been collected pre- and post-vaccination in each seasons. We constructed antibody landscapes utilizing hemagglutination inhibition antibody titers towards 16 A(H3N2) viruses consultant of main antigenic clusters that circulated between 1968 and 2015.

Results: The breadth of the antibody landscapes elevated with age. Vaccine-induced antibody responses correlated with boosting of titers to beforehand encountered antigens. Post-vaccination titers have been highest towards vaccine antigens reasonably than the historic A(H3N2) viruses beforehand encountered. Pre-vaccination titers to the vaccine have been the strongest predictors of post-vaccination titers. Responses to vaccine antigens didn’t differ by doubtless priming virus. Influenza A(H3N2) contaminated youngsters in 2014-15 had narrower antibody landscapes than these uninfected, however prior season an infection standing had little impact on antibody landscapes following 2015-16 vaccination.

Conclusions: A(H3N2) antibody landscapes in youngsters have been largely decided by age-related immune priming, reasonably than current vaccination or an infection.

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Adsorption of non-ionic surfactant and monoclonal antibody on siliconized floor studied by neutron reflectometry

  • The adsorption of monoclonal antibodies (mAbs) on hydrophobic surfaces is understood to trigger protein aggregation and degradation. Therefore, surfactants, comparable to Poloxamer 188, are extensively utilized in therapeutic formulations to stabilize mAbs and defend mAbs from interacting with liquid-solid interfaces. Here, the adsorption of Poloxamer 188, one mAb and their aggressive adsorption on a mannequin hydrophobic siliconized floor is investigated with neutron scattering coupled with distinction variation to find out the molecular construction of adsorbed layers for every case.
  • Small angle neutron scattering measurements of the affinity of Poloxamer 188 to this mAb point out that there’s negligible binding at these answer circumstances. Neutron reflectometry measurements of the mAb present irreversible adsorption on the siliconized floor, which can’t be washed off with neat buffer. Poloxamer 188 will be adsorbed on the floor already occupied by mAb, which allows partial elimination of some adsorbed mAb by washing with buffer.
  • The adsorption of the surfactant introduces vital conformational adjustments for mAb molecules that stay on the floor. In distinction, if the siliconized floor is first saturated with the surfactant, no adsorption of mAb is noticed. Competitive adsorption of mAb and Poloxamer 188 from answer results in a floor dominantly occupied with surfactant molecules, whereas solely a minor quantity of mAb absorbs. These findings clearly point out that Poloxamer 188 can defend towards mAb adsorption in addition to modify the adsorbed conformation of beforehand adsorbed mAb.

Antibody kinetics and serologic profiles of SARS-CoV-2 an infection utilizing two serologic assays

Background: Coronavirus illness 2019 (COVID-19) is an rising risk worldwide. This research goals to evaluate the serologic profiles and time kinetics of antibodies towards extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in sufferers with COVID-19 utilizing two immunoassays.

Methods: A complete of 97 samples serially collected from 17 sufferers with COVID-19 and 137 adverse management samples have been analyzed for IgM and IgG towards SARS-CoV-2 utilizing the AFIAS COVID-19 Ab (Boditech Med Inc., Chuncheon, Republic of Korea) and the EDI™ Novel Coronavirus COVID-19 ELISA Kit (Epitope Diagnostics, Inc., San Diego, CA).

Results: With each assays, IgM and IgG quickly elevated after 7 days submit symptom onset (PSO). IgM antibody ranges reached a peak at 15-35 d PSO and regularly decreased. IgG ranges regularly elevated and remained at comparable ranges after 22-35 d. The diagnostic sensitivities of IgM/IgG for ≤14d PSO have been 21.4%/35.7~57.1% and elevated to 41.2~52.9%/88.2~94.1% at >14 d PSO with specificities of 98.5%/94.2% for AFIAS COVID-19 Ab and 100.0%/96.4% for EDI™ Novel Coronavirus COVID-19 ELISA Kit. Among 137 adverse controls, 12 samples (8.8%) confirmed constructive or indeterminate outcomes.

Conclusions: The antibody kinetics towards SARS-CoV-2 are just like widespread findings of acute viral infectious ailments. Antibody testing is helpful for ruling out SARS-CoV-2 an infection after 14 d PSO, detecting previous an infection, and epidemiologic surveys.

A cancer-specific anti-podocalyxin monoclonal antibody (60-mG 2a-f) exerts antitumor results in mouse xenograft fashions of pancreatic carcinoma

  • Overexpression of podocalyxin (PODXL) is related to development, metastasis, and poor outcomes in a number of cancers. PODXL additionally performs an vital position within the growth of regular tissues. For antibody-based remedy to focus on PODXL-expressing cancers utilizing monoclonal antibodies (mAbs), cancer-specificity is important to scale back the danger of hostile results to regular tissues.
  • In this research, we developed an anti-PODXL cancer-specific mAb (CasMab), named as PcMab-60 (IgM, kappa) by immunizing mice with soluble PODXL, which is overexpressed in LN229 glioblastoma cells. The PcMab-60 reacted with the PODXL-overexpressing LN229 (LN229/PODXL) cells and MIA PaCa-2 pancreatic most cancers cells in move cytometry however didn’t react with regular vascular endothelial cells (VECs), whereas considered one of non-CasMabs, PcMab-47 confirmed excessive reactivity for not solely LN229/PODXL and MIA PaCa-2 cells but in addition VECs, indicating that PcMab-60 is a CasMab.
  • Next, we engineered PcMab-60 right into a mouse IgG2a-type mAb, named as 60-mG2a, so as to add antibody-dependent mobile cytotoxicity (ADCC). We additional developed a core fucose-deficient kind of 60-mG2a, named as 60-mG2a-f, to increase its ADCC exercise. In vivoevaluation revealed that 60-mG2a-f exerted antitumor exercise in MIA PaCa-2 xenograft fashions at a dose of 100 μg/mouse/week administered thrice. These outcomes steered that 60-mG2a-f might be helpful for antibody-based remedy towards PODXL-expressing pancreatic cancers.

Factors Involved within the Development of Inhibitory Antibodies in Patients with Hemophilia in Colombia: A Case-Control Study

Background: The look of inhibitory antibodies towards antihemophilic components is likely one of the most severe issues associated to hemophilia.

Objective: The goal of this research was to establish variables and components associated to the event of inhibitory antibodies in a gaggle of sufferers present process antihemophilic remedy in Colombia.

Methods: A case-control research in sufferers with hemophilia handled in Specialized Healthcare Provider Institutions (IPS-E) in 21 cities of Colombia of any age and with a analysis of inhibitory antibodies towards issue VIII or IX throughout 2016. Four controls per case paired by age and kind of hemophilia have been used. Sociodemographic, medical, and pharmacological variables have been recognized and analyzed.

Results: Seventeen sufferers with inhibitory antibodies and 68 controls with hemophilia have been recognized. The imply age was 28.3 ± 17.Eight years. A complete of 94.1% had hemophilia A, and 88.2% of the circumstances and 50.0% of the controls had extreme hemophilia; 47.1% of the circumstances and 54.4% of the controls have been receiving prophylaxis with coagulation components. Multivariate evaluation confirmed that having extreme hemophilia (OR:17.0, 95%CI:1.32-219.60) and lack of understanding of the coagulation issue with which the affected person was handled earlier than coming into the care program within the IPS-E (OR:8.9, 95%CI:1.82-43.75) have been considerably related to the next likelihood of growing inhibitory antibodies.

Conclusion and relevance: Coagulation components related to the event of inhibitory antibodies have been extreme hemophilia and lack of understanding of the kind of issue used previous to coming into the follow-up cohort.


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Systemic phenotype associated to major Sjögren’s syndrome in 279 sufferers

Systemic phenotype associated to major Sjögren’s syndrome in 279 sufferers carrying remoted anti-La/SSB antibodies

 

Objectives: To consider the systemic phenotype related to the presence of remoted anti-La/SSB antibodies in a big worldwide registry of sufferers with major Sjögren’s syndrome (pSS) fulfilling the 2002 classification standards.

 

Methods: The Big Data Sjögren Project Consortium is a world, multicentre registry created in 2014. Baseline scientific info from main centres on scientific analysis in SS of the 5 continents was collected. Combination patterns of anti-Ro/SSA-La/SSB antibodies on the time of analysis outlined the next 4 immunological phenotypes: double optimistic (mixed Ro/SSA and La/SSB,) remoted anti-Ro/SSA, remoted anti-La/SSB, and immunonegative.

 

Results: The cohort included 12,084 sufferers (11,293 females, imply 52.Four years) with recorded ESSDAI scores out there. Among them, 279 (2.3%) had remoted anti-La/SSB antibodies. The imply whole ESSDAI rating at analysis of sufferers with pSS carrying remoted anti-La/SSB was 6.0, and 80.4% of sufferers had systemic exercise (international ESSDAI rating ≥1) at analysis. The domains with the very best frequency of lively sufferers had been the organic (42.8%), glandular (36.8%) and articular (31.2%) domains.

 

Patients with remoted anti-La/SSB confirmed the next frequency of lively sufferers in all ESSDAI domains however two (articular and peripheral nerve) as compared with immune-negative sufferers, and even the next absolute frequency in six scientific ESSDAI domains as compared with sufferers with remoted anti-Ro/SSA.

In addition, sufferers with remoted anti-La/SSB confirmed the next frequency of lively sufferers in two ESSDAI domains (pulmonary and glandular) with respect to essentially the most lively immunological subset (double-positive antibodies). Meanwhile, systemic exercise detected in sufferers with remoted anti-La/SSB was overwhelmingly low. Even in ESSDAI domains the place sufferers with remoted anti-La/SSB had the very best frequencies of systemic exercise (lymphadenopathy and muscular), the share of sufferers with average or excessive exercise was decrease as compared with the mixed Ro/SSA and La/SSB group.

 

Conclusions: Patients carrying remoted La/SSB antibodies symbolize a really small subset of sufferers with a systemic SS phenotype characterised by a big frequency of lively sufferers in most scientific ESSDAI domains however with a relative low frequency of the very best extreme organ-specific involvements. Primary SS nonetheless stays the most effective scientific analysis for this subset of sufferers.

 

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Seroprevalence of Specific Antibodies in opposition to SARS-CoV-2 from Hotspot Communities within the Dominican Republic

 

  • Seroprevalence surveys are of utmost significance to evaluate the proportion of a inhabitants that has developed antibodies in opposition to a newly launched virus and will subsequently probably exhibit immunologic safety in opposition to subsequent an infection. This research goals to know the distribution of IgM and IgG antibodies within the Dominican Republic.
  • We surveyed a complete of 12,897 contributors between April and June 2020 in 10 provinces of the Dominican Republic. Survey efforts in rising hotspots yielded a positivity for all contributors of anti-SARS-CoV-2 IgM of three.8% and IgG of 5.4%, indicating that the pathogen was in circulation earlier than the identification of these specific communities as hotspots.
  • We discovered vital age variations between contributors who participated within the serological research the place the next imply age is related IgM positivity and a decrease age with IgG positivity. Our outcomes spotlight the necessity for methods that contain community-based seroprevalence monitoring. These ought to preclude syndromic case identification.
  • Also, the upper imply age of IgM-positive contributors means that methods primarily based on syndromic surveillance may establish hotspots at later phases, primarily based on the variety of instances detected on the healthcare heart, as such community-based seroprevalence monitoring could also be an efficient intervention for future outbreaks.

SARS-CoV-2 antibody prevalence, titres and neutralising exercise in an antenatal cohort, United Kingdom, 14 April to 15 June 2020

 

SARS-CoV-2 IgG screening of 1,000 antenatal serum samples within the Oxford space, United Kingdom, between 14 April and 15 June 2020, yielded a 5.3% seroprevalence, mirroring contemporaneous regional knowledge. Among the 53 optimistic samples, 39 confirmed in vitro neutralisation exercise, correlating with IgG titre (Pearson’s correlation p<0.0001). While SARS-CoV-2 seroprevalence in being pregnant cohorts may probably inform inhabitants surveillance, scientific correlates of an infection and immunity in being pregnant, and antenatal epidemiology evolution over time want additional research.

Coronavirus Disease 2019 in a Premature Infant: Vertical Transmission and Antibody Response or Lack Thereof

With the worldwide unfold of extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) an infection, a number of studies spotlight its results on pregnant ladies. Based on scant out there knowledge, vertical transmission is taken into account unlikely. We current right here a preterm neonate born to a critically sick mom with SARV-CoV-2 with early proof of an infection with a optimistic reverse transcription polymerase chain response on day 1.

Lack of parental contact previous to testing and strict adherence to really helpful airborne precautions perinatally recommend vertical transmission of an infection. Critical maternal sickness and medicines might have contributed to the necessity for intensive resuscitation at beginning and spotlight the significance of shut fetal monitoring. Infant lacked immunoglobulin G antibody response by Three weeks, presumably secondary to delicate scientific course and prematurity. Effects of SARS-CoV-2 in preterm infants, their antibody response and potential for asymptomatic carriage stay unsure.

 

Towards middle-up evaluation of polyclonal antibodies: subclass-specific N-glycosylation profiling of murine immunoglobulin G (IgG) by the use of HPLC-MS

 

  • In current years, superior HPLC-MS methods primarily based on intact protein (“top-down”) or protein subunit (“middle-up/middle-down”) evaluation have been carried out for the characterization of therapeutic monoclonal antibodies. Here, we assess feasibility of middle-up/middle-down evaluation for polyclonal IgGs exhibiting intensive sequence variability. Specifically, we addressed IgGs from mouse, representing an vital mannequin system in immunological investigations.
  • To receive Fc/2 parts as conserved subunits of IgGs, we made use of the bacterial protease SpeB. For this goal, we initially decided SpeB cleavage websites in murine IgGs. The ensuing Fc/2 parts attribute of various subclasses had been subsequently analysed by ion-pair reversed-phase HPLC hyphenated to high-resolution mass spectrometry.
  • This enabled simultaneous relative quantification of IgG subclasses and their N-glycosylation variants, each of which affect IgG effector capabilities. To assess methodology capabilities in an immunological context, we utilized the analytical workflow to polyclonal antibodies obtained from BALB/c mice immunized with the grass pollen allergen Phl p 6.
  • The research revealed a shift in IgG subclasses and Fc-glycosylation patterns in whole and antigen-specific IgGs from totally different mouse cohorts, respectively. Eventually, Fc/2 characterization might reveal different protein modifications together with oxidation, amino acid exchanges, and C-terminal lysine, and should thus be carried out for high quality management of useful antibodies.

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Moxifloxacin-Induced Thrombocytopenia Mediated by Moxifloxacin

Moxifloxacin-Induced Thrombocytopenia Mediated by Moxifloxacin-Dependent IgM and IgG Antiplatelet Antibodies: A Case Report

 

  • Moxifloxacin is a rare but important cause of drug-induced immune thrombocytopenia (DIT). We describe a patient who presented with an acute onset of severe thrombocytopenia complicated by petechial rash, epistaxis, and melena. Recent new drug exposures included moxifloxacin and two proton pump inhibitors.

 

  • On presentation to the hospital, all recently initiated medications were discontinued and the patient’s thrombocytopenia was treated with platelet transfusions, intravenous immunoglobulin, and high-dose corticosteroids. Her thrombocytopenia improved over the next seven days and she was discharged on hospital day 8.

 

  • Serologic testing revealed strongly positive moxifloxacin-dependent IgM and IgG antiplatelet antibodies, confirming a diagnosis of moxifloxacin-induced immune thrombocytopenia. DIT has been reported with other fluoroquinolone antibiotics, especially ciprofloxacin. This case documents a rare but potentially fatal complication of exposure to moxifloxacin and is the first to demonstrate objective evidence of acute sensitization with IgM antibody positivity.

 

  • It highlights the need to consider this potential reaction when choosing antibiotic therapy, particularly in patients who are at high risk for bleeding, have hematologic disorders, or are receiving myelosuppressive therapies, and perhaps in those with a history of multiple drug allergies.

 

Inhibitory anti ADAMTS13 antibodies with a new rapid fully automated CLiA assay

 

Background: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disorder characterized by severe ADAMTS13 deficiency. The acquired form is associated with autoantibodies directed against ADAMTS13. Both noninhibitory and inhibitory autoantibodies can be detected by ELISA assay, while only inhibitory autoantibodies are detected by Bethesda assay. Due to its short TAT and good performance, chemiluminescence (CliA) ADAMTS13 activity (HemosIL Acustar) has proven to be a good choice in the diagnosis of TTP in emergency settings. Aim of this study was to analyse the performance of the CliA ADAMTS13 activity assay in detecting inhibitory ADAMTS13 antibodies using the Bethesda assay.

 

Methods: A method comparison study was performed on 69 stored samples: 11 acute TTPs, 38 TTP follow-ups, 5 TTP relapses, 1 congenital TTP, 10 HUS, 4 suspected TTPs. We retrieved the results of tests previously run in ELISA for both activity and autoantibodies. At the same time, we reran new tests including ELISA and CliA activity, ELISA autoantibodies, and ELISA and CliA Bethesda assays on thawed frozen samples.

 

Results: Very good correlation was observed between ELISA and CliA activity assay results (r = 0.96) and between archived ELISA and CliA activity results (r = 0.93). Agreement between the anti-ADAMTS13 assays ranged from good (k = 0.63) to very good (k = 0.92).

 

Conclusions: CliA and ELISA Bethesda assays showed very good agreement with samples run at the same time using ELISA ADAMTS13-autoantibody assay. Albeit more expensive, the CliA Bethesda assay identified inhibitory anti-ADAMTS13 within almost the same TAT as ELISA, but with better automation and limited operator involvement.

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Development of a multiplex microsphere immunoassay for the detection of antibodies against highly pathogenic viruses in human and animal serum samples

 

Surveillance of highly pathogenic viruses circulating in both human and animal populations is crucial to unveil endemic infections and potential zoonotic reservoirs. Monitoring the burden of disease by serological assay could be used as an early warning system for imminent outbreaks as an increased seroprevalance often precedes larger outbreaks.

However, the multitude of highly pathogenic viruses necessitates the need to identify specific antibodies against several targets from both humans as well as from potential reservoir animals such as bats. In order to address this, we have developed a broadly reactive multiplex microsphere immunoassay (MMIA) for the detection of antibodies against several highly pathogenic viruses from both humans and animals.

To this aim, nucleoproteins (NP) of Ebola virus (EBOV), Marburg virus (MARV) and nucleocapsid proteins (NP) of Crimean-Congo haemorrhagic fever virus, Rift Valley fever virus and Dobrava-Belgrade hantavirus were employed in a 5-plex assay for IgG detection. After optimisation, specific binding to each respective NP was shown by testing sera from humans and non-human primates with known infection status.

The usefulness of our assay for serosurveillance was shown by determining the immune response against the NP antigens in a panel of 129 human serum samples collected in Guinea between 2011 and 2012 in comparison to a panel of 88 sera from the German blood bank. We found good agreement between our MMIA and commercial or in-house reference methods by ELISA or IIFT with statistically significant higher binding to both EBOV NP and MARV NP coupled microspheres in the Guinea panel.

Finally, the MMIA was successfully adapted to detect antibodies from bats that had been inoculated with EBOV- and MARV- virus-like particles, highlighting the versatility of this technique and potentially enabling the monitoring of wildlife as well as human populations with this assay. We were thus able to develop and validate a sensitive and broadly reactive high-throughput serological assay which could be used as a screening tool to detect antibodies against several highly pathogenic viruses.

Maternal Epstein-Barr virus-specific antibodies and risk of infection in Ugandan infants

 

Background: Epstein-Barr virus (EBV) infection is a major cause of malignancy worldwide. Maternal antibody is thought to prevent EBV infection because it is uncommon in early infancy. Maternal HIV infection is associated with an increased incidence of EBV infection in exposed infants, which we hypothesized results from impaired transfer of EBV-neutralizing maternal antibodies.

 

Methods: Among Ugandan infants followed for EBV acquisition from birth, we measured antibody binding to EBV glycoproteins (e.g., gp350, gH/gL) involved in B cell and epithelial cell entry, as well as viral neutralization and antibody-dependent cellular cytotoxicity (ADCC) activity in plasma samples prior to infection. These serologic data were analyzed for differences between HIV-exposed uninfected (HEU) and unexposed (HUU) infants, and for associations with incident infant EBV infection.

 

Results: HEU infants had significantly higher titers than HUU infants for all EBV-binding and neutralizing antibodies measured (p<0.01), but not ADCC activity, which was similar between groups. No antibody measure was associated with a decreased risk of EBV acquisition in the cohort.

 

Conclusions: Our findings indicate that in this cohort maternal antibody did not protect infants against EBV infection through viral neutralization. The identification of protective non-neutralizing antibody functions would be invaluable for the development of an EBV vaccine