Immunoglobulins M (IgMs) are the evolutionally oldest class of antibodies in higher eukaryotes. This pool of antibodies is one of the first to appear in humans and begins to be-synthesized at the early stages of the neonatal period. Most of the repertoire of IgMs of the newborns consists of the so-called «natural», or «naive», antibodies synthesized by the body without external antigenic stimulation. In addition to the classical functions of human immunoglobulins M (such as antigen recognition and initiation of innate immune responses), antibodies of this class exhibit a variety of non-canonical functions. The non-canonical functions are the action of antibodies as agonists/antagonists of various receptors, cleavage of antigen due to the catalytic activity of IgM, direct inactivation of pathogens in the absence of effector cells and molecules, etc. The aim of this work was to study and compare the antiviral activity of total preparations of immunoglobulin M of newborns and adults, obtained from umbilical cord and venous blood sera, on the LLC-PK1 cell line model infected with the transmissible gastroenteritis virus (TGEV). In addition, in the course of the studies, a decision was made to investigate the effect of combined preparations of immunoglobulin M on the change in signal transduction in the epidermal growth factor receptor as one of the mechanisms of TGEV internalization during infection of target cells. Methods. Highly purified preparations of total IgM of adults or newborns were obtained using the methodologies of sequential salt fractionation and affinity chromatography. This work used the model of the interaction of the transmissible gastroenteritis virus with cells of the LLC-PK1 line and the monitoring of changes in the phosphorylation state of the epidermal growth factor receptor of these cells during virus infection to study the effect of human IgM on the internalization of the virus and its interaction with the receptor system of the host cell. The degree of cytopathogenic effect of the virus was determined visually by changes in cell morphology. The mean infectious dose for transmissible gastroenteritis virus in the cell culture of the LLC-PK1 line was determined by the Reed-Muench method. Analysis of changes in the phosphorylation of the epidermal growth factor receptor was performed using the Western-blot analysis method. Results. The addition of a total high-purified sample of human IgM reduces the degree of efficiency of TGEV infection of the LLC-PK1 cell line and modulates the phosphorylation levels of these cells. Conclusions. The total preparations of IgM obtained from human venous blood of adults and from umbilical cord blood of newborns can affect the internalization of the transmissible gastroenteritis virus in the LLC-PK1 cell line. The original model of virus (TGEV) — cell line (LLC-PK1) was applied and tested to study the effect of native total preparations of immunoglobulin M on the internalization of the virus into the cell. The obtained data can be useful in further studies for a better understanding of the process of development and functioning of the immune system of newborns.
The first-generation tests targeting a cryptic plasmid for the C. trachomatis diagnostics showed a relatively high sensitivity; however their usefulness has recently been compromised by the discovery of C. trachomatis strains lacking the target DNA segment (e.g. the "Swedish" variant) or variants bearing no plasmid at all and thus escaping the diagnostics. Aim. We propose the addition of a C. trachomatis chromosome gene as a PCR target to back up plasmidbased assays and enhance the overall efficiency of diagnostics. Methods. Two multiplexed PCRs were set up to target C. trachomatis cryptic plasmid and the 16s rRNA gene. The 16s rRNA primers produce PCR signal from a range of Chlamydia species whereas the introduction of a Taqman probe (essential for the real-time PCR) scales the assay down to C. trachomatis. At the same time, our plasmid PCR is specific to C. trachomatis exclusively. Results. The sensitivity of plasmid and 16s rRNA PCRs ranged between one to ten genome-equivalents per reaction (geq/rxn) whereas the efficiency was always ~100%. Multiplexing did not reduce the analytical sensitivity. Addition of DNA prepared from clinical specimens to the reaction mix did not affect PCR with pure C. trachomatis DNA further demonstrating the robustness of this system. The kinetics of the two reactions was compared in 49 DNA samples prepared from C. trachomatis-positive swabs. In 45, reactions showed a good correlation in the threshold cycle of amplification Cq, the main analytical parameter of real-time PCR. Conclusions. The simultaneous detection of chromosomal and plasmid targets in the multiplex PCR offers a high sensitivity and is particularly advantageous for specimens where the plasmid might be lost due to DNA degradation or counter-selection after treatment. The dual PCR strategy constitute the core of a diagnostic test for both in-house and commercial use.
Enterovirus infections remain one of the urgent problems in modern infectious pathology and are represented in numerous publications of domestic and foreign researchers, including publications in the field of veterinary virology. The causative agents of enterovirus infections of viral etiology (enteroviruses) are characterized by relative resistance to adverse environmental conditions, including thermal stability, acid resistance, resistance to proteolytic enzymes, which allows them to survive in the environment and facilitates their transmission by various ecological routes (water, food, aerosols, contaminated objects, etc.). The purpose of this study was to elucidate the changes in the infectious properties of porcine enteroviruses in vitro under conditions of long-term storage at a temperature of minus 32 °C. In the course of this study, a re- cultivation process was carried out with the subsequent adaptation of two variants of viruses: the porcine teschovirus of the first serotype (Teschovirus A), the “Dniprovsky 34” strain and Porcine sapelovirus 1 (porcine enterovirus of serogroup 8), the reference V-13 strain. The re-cultivation was performed on BHK-21 cell cultures / clone 13 and on SPEV, in which they were previously cultivated, in order to determine the infectious activity after storage under negative temperatures (minus 32 °C) for two and twenty years. On the example of porcine enterovirus of serogroup 8 (the causative agent of viral gastroenteritis), it was proved that during long-term storage (20 years) at a temperature of – 32 °C, the virus did not lose its infectious properties, although a change in the cytopathogenic effect in vitro during re-cultivation was found. The infectious properties of the porcine teshovirus of the first serotype are also capable of long-term storage (2 years) under conditions of minus 32 °C temperature.
Infectious rhinitis is a respiratory bacterial disease in poultry that can lead to significant economic losses. The article provides an analysis of literature data on the current epizootic situation on infectious rhinitis in different countries of the world, an analysis of the economic losses that may be caused by the appearance of this pathogen in the poultry farm. For today in Ukraine, the situation for haemophilus infection in poultry is unknown. It is not included to the list of particularly dangerous infectious diseases and therefore infection cases officially are not reported. But this issue exists in poultry farms of Ukraine and therefore, the main goal of our work was to study the occurrence of haemophilus causative agent in poultry farms of different age, with different types of production and in various regions of Ukraine. As the results of PCR studies conducted in 2015-2018, haemophilus causative agent was detected in 8 out of 18 studied farms. Pathogen's circulation was detected in poultry farms in 8 oblasts of Ukraine in Western, Eastern, Central and Southern regions. Herewith, the pathogen was detected both in layer hens, in broilers and in broiler parent flock. The pathogen was detected in Ukraine in poultry of different age groups. The presence of this pathogen in pathological/clinical material was 20-100 %, on average, this index varied 28,28-64,51%. Identification of pathogen in Ukraine testifies to the relevance of this disease for our country, as well as the need for in-depth study of the pathogen, improvement of laboratory diagnostics and specific prevention.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.