Novel monoclonal antibodies against house dust mite allergen Der p 21 and their application to analyze allergen extracts.

Background: Allergen extracts and recombinant allergens are used in allergy diagnostics and immunotherapy. Since allergen extracts from different manufacturers lack proper standardization regarding their composition, monoclonal antibodies (MAbs) against specific allergen components can be used for their identification and quantification in allergen extracts. This study aimed to generate MAbs against allergen Der p 21 of for the analysis of allergen extracts.

Molecular characteristics of Neisseria meningitidis carriage strains in university students in Lithuania.

Background: Neisseria meningitidis can be carried asymptomatically in the human oropharynx without causing symptoms. Meningococcal carriage is relevant to the epidemiology of invasive meningococcal disease (IMD). No carriage studies have been performed among the general population in Lithuania, whereas the incidence of IMD in Lithuania was among the highest in European countries from 2009 to 2019.

Molecular characterization of invasive isolates collected in Lithuania (2009-2019) and estimation of serogroup B meningococcal vaccine 4CMenB and MenB-Fhbp coverage.

causes invasive meningococcal disease (IMD), which is associated with significant mortality and long-term consequences, especially among young children. The incidence of IMD in Lithuania was among the highest in European Union/European Economic Area countries during the past two decades; however, the characterization of meningococcal isolates by molecular typing methods has not yet been performed. In this study, we characterized invasive meningococcal isolates (n=294) recovered in Lithuania from 2009 to 2019 by multilocus sequence typing (MLST) and typing of antigens FetA and PorA.

Cross-reactive monoclonal antibodies against fish parvalbumins as a tool for studying antigenic similarity of different parvalbumins and analysis of fish extracts.

Fish parvalbumins are heat-stable calcium-binding proteins that are highly cross-reactive in causing allergy symptoms in fish-sensitized patients. The reactivities of parvalbumin-specific monoclonal or polyclonal antibodies with parvalbumins of different fish species allowed their application for development of various immunoassays for allergen identification in fish samples. In this study, monoclonal antibodies (MAbs) were generated against two parvalbumins - natural Atlantic cod parvalbumin and recombinant common carp β-parvalbumin expressed in E.

Discrimination of Species by Combining MALDI-TOF Protein Profile, Chaperonin Sequences, and Phenotypic Characteristics.

The description of was recently updated and three new species, including nine genome species within , were defined using whole genome sequences and matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry. A fast and simple method based on readily available techniques would be of immense use to identify species in research and clinical practice. Here we show that 34 previously characterized isolates were assigned to the species using partial chaperonin sequences.

Human granulocyte-colony stimulating factor (G-CSF)/stem cell factor (SCF) fusion proteins: design, characterization and activity.

Background: Stem cell factor (SCF) and granulocyte-colony stimulating factor (G-CSF) are well-characterized vital hematopoietic growth factors that regulate hematopoiesis. G-CSF and SCF synergistically exhibit a stimulatory effect on hematopoietic progenitors. The combination of G-CSF and SCF has been used for mobilization of peripheral blood progenitor cells in cancer and non-cancerous conditions.

Type II Restriction-Modification System from ATCC 14018.

Intensive horizontal gene transfer may generate diversity and heterogeneity within the genus . Restriction-modification (R-M) systems and CRISPR-Cas are the principal defense tools against foreign DNA in bacteria. Nearly half of the tested spp.

Mapping of Recognition Sites of Monoclonal Antibodies Responsible for the Inhibition of Pneumolysin Functional Activity.

The pathogenicity of many bacteria, including depends on pore-forming toxins (PFTs) that cause host cell lysis by forming large pores in cholesterol-containing cell membranes. Therefore, PFTs-neutralising antibodies may provide useful tools for reducing pathogenic effects. This study aimed at the development and characterisation of monoclonal antibodies (MAbs) with neutralising activity to PFT pneumolysin (PLY).

Cholesterol-Dependent Cytolysins Produced by Vaginal Bacteria: Certainties and Controversies.

Bacterial vaginosis (BV) is a vaginal anaerobic dysbiosis that affects women of reproductive age worldwide. BV is microbiologically characterized by the depletion of vaginal lactobacilli and the overgrowth of anaerobic bacterial species. Accumulated evidence suggests that spp.

Inerolysin and vaginolysin, the cytolysins implicated in vaginal dysbiosis, differently impair molecular integrity of phospholipid membranes.

The pore-forming toxins, inerolysin (INY) and vaginolysin (VLY), produced by vaginal bacteria Lactobacillus iners and Gardnerella vaginalis were studied using the artificial cholesterol-rich tethered bilayer membranes (tBLMs) by electrochemical techniques. The electrochemical impedance spectroscopy (EIS) of tBLMs attested for the toxin-induced impairment of the integrity of phospholipid membranes. This observation was in line with the atomic force microscopy data demonstrating formation of oligomeric protein assemblies in tBLMs.

Phenotypic characterization of Gardnerella vaginalis subgroups suggests differences in their virulence potential.

The well-known genotypic and phenotypic diversity of G. vaginalis resulted in its classification into at least four subgroups (clades) with diverse genomic properties. To evaluate the virulence potential of G.

Construction, Purification, and Characterization of a Homodimeric Granulocyte Colony-Stimulating Factor.

Granulocyte colony-stimulating factor (G-CSF) has found widespread clinical application, and modified forms with improved biopharmaceutical properties have been marketed as well. PEGylation, the covalent modification of G-CSF with polyethylene glycol (PEG), has a beneficial effect on drug properties, but there are concerns connected to the immunogenicity of PEGylated compounds and bioaccumulation of the synthetic polymer. To overcome challenges connected with chemical modifications, we developed fusion proteins composed of two G-CSF molecules connected via different peptide linkers.

Prevalence and distribution of Gardnerella vaginalis subgroups in women with and without bacterial vaginosis.

Background: Bacterial vaginosis (BV) is one of the leading causes of vaginal complaints among women of childbearing age. The role of Gardnerella vaginalis remains controversial due to its presence in healthy and BV-type vaginal microflora. The phenotypic and genotypic heterogeneity of G.

Gardnerella vaginalis bacteremia associated with severe acute encephalopathy in a young female patient.

Gardnerella vaginalis is a facultative anaerobic bacterium that inhabits the genitourinary tract of both healthy women and those with bacterial vaginosis. We report a case of G. vaginalis bacteremia associated with severe toxic encephalopathy in a young woman.

New broadly reactive neutralizing antibodies against hepatitis B virus surface antigen.

Hepatitis B virus (HBV) surface antigen (HBsAg) is considered to be the most important target for the diagnosis and immune prophylaxis of HBV infection. HBsAg-specific monoclonal antibodies (MAbs) are extensively used for studying the complex structure of the HBsAg, mapping the neutralizing epitopes and development of HBV diagnostic tests. However, the efficiency of anti-HBV binding strongly depends on the epitope structure and MAb capability to recognize different HBV variants.

Construction of polyomavirus-derived pseudotype virus-like particles displaying a functionally active neutralizing antibody against hepatitis B virus surface antigen.

Background: Virus-like particles (VLPs) can be efficiently produced by heterologous expression of viral structural proteins in yeast. Due to their repetitive structure, VLPs are extensively used for protein engineering and generation of chimeric VLPs with inserted foreign epitopes. Hamster polyomavirus VP1 represents a promising epitope carrier.

The cytolytic activity of vaginolysin strictly depends on cholesterol and is potentiated by human CD59.

Gardnerella vaginalis produces cytolysin vaginolysin (VLY), which has been suggested to be a contributor to bacterial vaginosis pathogenesis. VLY along with intermedilysin (ILY) from Streptococcus intermedius have been attributed to a group of cholesterol-dependent cytolysins (CDCs) whose pore-forming activity depends on human CD59 (hCD59). Here, we show that different types of cells lacking hCD59 are susceptible to VLY-mediated lysis, albeit to different extents.

Reconstitution of cholesterol-dependent vaginolysin into tethered phospholipid bilayers: implications for bioanalysis.

Functional reconstitution of the cholesterol-dependent cytolysin vaginolysin (VLY) from Gardnerella vaginalis into artificial tethered bilayer membranes (tBLMs) has been accomplished. The reconstitution of VLY was followed in real-time by electrochemical impedance spectroscopy (EIS). Changes of the EIS parameters of the tBLMs upon exposure to VLY solutions were consistent with the formation of water-filled pores in the membranes.

Insights into the CRISPR/Cas system of Gardnerella vaginalis.

Background: Gardnerella vaginalis is identified as the predominant colonist of the vaginal tracts of women diagnosed with bacterial vaginosis (BV). G. vaginalis can be isolated from healthy women, and an asymptomatic BV state is also recognised.

Genetic and biochemical diversity of Gardnerella vaginalis strains isolated from women with bacterial vaginosis.

Gardnerella vaginalis is considered a substantial player in the progression of bacterial vaginosis (BV). We analysed 17 G. vaginalis strains isolated from the genital tract of women diagnosed with BV to establish a potential link between genotypes/biotypes and the expression of virulence factors, vaginolysin (VLY) and sialidase, which are assumed to play a substantial role in the pathogenesis of BV.

Production in yeast of pseudotype virus-like particles harboring functionally active antibody fragments neutralizing the cytolytic activity of vaginolysin.

Background: Recombinant antibodies can be produced in different formats and different expression systems. Single chain variable fragments (scFvs) represent an attractive alternative to full-length antibodies and they can be easily produced in bacteria or yeast. However, the scFvs exhibit monovalent antigen-binding properties and short serum half-lives.

Generation of recombinant single-chain antibodies neutralizing the cytolytic activity of vaginolysin, the main virulence factor of Gardnerella vaginalis.

Background: Gardnerella vaginalis is identified as the predominant colonist of the vaginal tract in women with bacterial vaginosis. Vaginolysin (VLY) is a protein toxin released by G. vaginalis.

Production and characterization of monoclonal antibodies against vaginolysin: mapping of a region critical for its cytolytic activity.

Vaginolysin (VLY) is a protein toxin released by Gardnerella vaginalis. VLY belongs to the group of cholesterol-dependent cytolysins (CDCs). We have generated a panel of novel monoclonal antibodies (MAbs) against VLY.

[Alzheimer's disease: a molecular mechanism, new hypotheses, and therapeutic strategies].

Human diseases involving protein misfolding and aggregation have received increasing attention in recent years. Alzheimer's disease and other diseases associated with aging are sweeping the developed countries whose populations are rapidly aging. Recent progress has improved our knowledge about molecular and cellular pathogenesis of these diseases.

Mapping of an antigenic site on the nucleocapsid protein of human parainfluenza virus type 3.

Human parainfluenza virus type 3 (hPIV3) is a respiratory tract pathogen. The current study aimed to investigate immunodominant regions of hPIV3 nucleocapsid (N) protein by using monoclonal antibodies (mAbs) raised against recombinant N protein and human serum specimens from hPIV3-infected individuals. A panel of murine mAbs was generated following immunization with yeast-expressed hPIV3 N protein self-assembled to nucleocapsid-like particles.