Presence Of Specific Antibodies Research Articles

A serological survey of canine leptospirosis in the city of Belgrade, Serbia

Canine leptospirosis is a zoonosis caused by bacteria belonging to the genus Leptospira. Dogs are one of the animal species involved in the cycle of preservation and transmission of leptospirosis in urban areas. Serological testing for the presence of specific antibodies against Leptospira spp. in dogs was continuously performed between 2010 and 2020 in the city of Belgrade. At the request of the owners themselves, other veterinary laboratories or laboratory clinics, 179 blood sera from 179 dogs were examined in the Laboratory for Immunology, Scientific Institute of Veterinary Medicine of Serbia. Blood sera samples from dogs were examined using the standard microscopic agglutination test (MAT) for the presence of specific antibodies against seven different serovars of Leptospira: Pomona, Icterohaemorrhagiae, Grippotyphosa, Sejroe, Canicola, Bataviae, and Australis. The number of seropositive dogs was 17/179 (9.5%). Among all examined sera, the highest titre of seropositive samples was to serovar Icterohaemorrhagiae (10/17, 58.8%), followed by Pomona (4/17, 23.5%), and serovar Canicola (3/17, 17.6%). Specific antibodies for serovars Grippotyphosa, Sejroe, Bataviae and Australis were not detected in any of the dog sera. Cross-reaction (the presence of two or three titres with different values where one of them was higher than others) between different serovars was diagnosed in a low number of sera (n=4), with the following serovars: Icterohaemorrhagiae and Pomona (n=3) and Pomona and Canicola (n=1). The confirmed specific antibody titres for Leptospira spp. were between 1:100 to 1:3000 (5 sera had titres of 1:100, 7 had titres of 1:300, 4 had titres of 1:1000, and 1 serum had a titre 1:3000). Monitoring canine leptospirosis is a useful tool in preventing leptospirosis in Belgrade.

Viruses in food products

Data on viral food contaminants that are actually or potentially capable of realizing the food route of infection are presented. The main sources of infection of food with viruses are named: human waste / faeces, contaminated food processing facilities, animals-carriers of zooanthroponotic infections. The groups of viruses transmitted through food are characterized: 1) gastroenteritis pathogens – Sapporo and Norwalk viruses from the family Caliciviridae; Rotavirus A from the family Reoviridae; Mammastroviruses 1, 6, 8 and 9 from the family Astroviridae; Human mastadenovirus F from the family Adenoviridae; Aichivirus A from the family Picornaviridae; 2) Hepatovirus A from the family Picornaviridae and Orthohepevirus A from the family Hepeviridae (with replication in the liver); 3) viruses with replication in the human intestine, which after generalization of the infection affect the CNS – Еnteroviruses B and C from the family Picornaviridae. The stability and survival time of viruses in the environment and food are shown. The main ways of transmission of viruses that are able to enter the human body through infected foods are considered. Influenza A (H1N1) virus has been identified as a possible contaminant in pork and chicken, which without heat treatment can pose a potential risk of human infection. The ability of classical and African swine fever pathogens to remain viable after industrial processing of meat or raw meat has been shown. Families of viruses whose zoopathogenic representatives can contaminate meat products (beef, pork, chicken) are named: Parvoviridae, Anelloviridae, Circoviridae, Polyomaviridae, Smacoviridae. To determine the possible latent infection of people with these viruses, it is necessary to test sera for the presence of specific antibodies. The detection of gyroviruses of the family Anelloviridae and huchismacoviruses of the family Smacoviridae in human faeces may be due to the consumption of infected chicken meat. Data on extraction and concentration methods and methods of virus detection in contaminated food products: PCR (reverse transcription and real-time), ELISA, IСA, electron microscopy, virus isolation in transplanted cell cultures with subsequent identification in serological reactions, NR, IFА, ELISA) or PCR.

Identification of Immunogenic Linear B-Cell Epitopes in C. burnetii Outer Membrane Proteins Using Immunoinformatics Approaches Reveals Potential Targets of Persistent Infections.

Coxiella burnetii is a global, highly infectious intracellular bacterium, able to infect a wide range of hosts and to persist for months in the environment. It is the etiological agent of Q fever—a zoonosis of global priority. Currently, there are no national surveillance data on C. burnetii’s seroprevalence for any South American country, reinforcing the necessity of developing novel and inexpensive serological tools to monitor the prevalence of infections among humans and animals—especially cattle, goats, and sheep. In this study, we used immunoinformatics and computational biology tools to predict specific linear B-cell epitopes in three C. burnetii outer membrane proteins: OMP-H (CBU_0612), Com-1 (CBU_1910), and OMP-P1 (CBU_0311). Furthermore, predicted epitopes were tested by ELISA, as synthetic peptides, against samples of patients reactive to C. burnetii in indirect immunofluorescence assay, in order to evaluate their natural immunogenicity. In this way, two linear B-cell epitopes were identified in each studied protein (OMP-H(51–59), OMP-H(91–106), Com-1(57–76), Com-1(191–206), OMP-P1(197–209), and OMP-P1(215–227)); all of them were confirmed as naturally immunogenic by the presence of specific antibodies in 77% of studied patients against at least one of the identified epitopes. Remarkably, a higher frequency of endocarditis cases was observed among patients who presented an intense humoral response to OMP-H and Com-1 epitopes. These data confirm that immunoinformatics applied to the identification of specific B-cell epitopes can be an effective strategy to improve and accelerate the development of surveillance tools against neglected diseases.

The production of hyperimmune pseudotuberculosis sera

Background . Pseudotuberculosis remains a serious public health problem, which dictates the need to develop simple and rapid diagnostic methods for this disease. The effectiveness of the latter largely depends on the activity and specificity of the diagnostic sera. Currently, in our country, a diagnostic serum for Yersinia pseudotuberculosis O-monovalent (serotype I, III) is produced with a regulated area of application: for an approximate agglutination reaction on glass (Pasteur NIIEM, St. Petersburg). Preparation of pseudotuberculosis sera for a wider scope of their use, in particular, as a source of specific antibodies in the design of diagnostic immunobiological preparations and test systems for pseudotuberculosis, is relevant and in demand in healthcare practice. Aims . To obtain hyperimmune pseudotuberculosis sera, promising for use in the practice of laboratory studies for pseudotuberculosis. Materials and methods. Chinchilla rabbits aged 3–6 months, weighing 2.5–3.0 kg served as animal producers of pseudotuberculosis sera. As immunogens, we used a corpuscular antigen (CAg) - a suspension of cells of the epidemically significant Yersinia pseudotuberculosis 3704 O: 1b strain isolated by an outbreak of pseudotuberculosis in the town of Zima, Irkutsk region, inactivated by boiling, and a preparation obtained from the outer membranes, containing the main surface immunogen of the strain. For the adsorption of experimental sera, in order to minimize the nonspecific response, we used heterologous microorganisms Escherichiacoli, Salmonella typhimurium, Shigella flexneri and Y. enterocolitica O:3, which have a similarity of surface antigenic structures with the causative agent of pseudotuberculosis. The presence of specific antibodies in experimental pseudotuberculosis sera was determined in a volumetric agglutination reaction. Results . Optimal schemes of rabbit immunization were selected, which made it possible to obtain hyperimmune sera against Y. pseudotuberculosis 3704 O:1b antigens with an agglutination activity of 1:3200-1:6400. In low dilutions of experimental sera (1:100–1:400), obtained against corpuscular antigen and outer membrane antigens (Escherichia coli, Salmonella typhimurium, Shigella flexneri , Y. enterocolitica О:3, S . enteritidis Gartnery) was observed in the agglutination reaction (AR). After the adsorption of experimental pseudotuberculosis sera by cells of heterologous strains, there was no cross-reaction with the indicated microorganisms in the agglutination reaction. Conclusions . The obtained hyperimmune adsorbed sera against the boiling-inactivated Y. pseudotuberculosi s 3704 O: 1b corpuscular antigen and outer membrane antigens can be used as a source of specific antibodies in the design of diagnostic immunobiological preparations for the detection of pseudotuberculosis microbe, as well as in the monitoring of the epidemic situation.

Serological Evidence of Common Equine Viral Infections in a Semi-Isolated, Unvaccinated Population of Hucul Horses.

Simple SummaryThe aim of the following research was an analysis of the occurrence of common equine viral infections in a Hucul herd, based on serological studies. This study provides epidemiological data concerning animals representing a semi-isolated herd, devoid of any specific prophylaxis. The obtained results provide a source of information on a primitive breed of horses, as well as giving an insight into viruses (among them, arboviruses) circulating within a local ecosystem.Huculs (Equus caballus) are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal secretion swabs as a specimen source, isolation attempts were negative regarding ERAV, EHV-1, EAV, and EIV. According to the virus neutralisation method, in the sera obtained from the animals, antibodies against the following viruses were detected: EHV-1 in 12 horses (60%; with titres from 1:8 to 1:64), EIV A/H7N7 in 13 (65%; titres from 1:20 to 1:80), EIV A /H3N8 in 12 (60%; titres from 1:20 to 1:80), USUV in 5 (25%; titres from 1:10 to 1:80), and ERAV in 1 (5%; titre 1:32). Antibodies against EAV, EIAV, and WNV were not present in the tested sera. The detected presence of specific antibodies associated with five out of the eight equine viruses investigated indicates that the Hucul herd, due to its partial separation and lack of specific prophylaxis, could serve as a sentinel animal group for the detection of equine viruses/arboviruses present within the local ecosystem. The detection of common equine viral infections within the herd provides additional epidemiological data concerning the breed.

Performance of five rapid serological tests in mild-diseased subjects using finger prick blood for exposure assessment to SARS-CoV-2.

ObjectivesAssess the performance of five SARS-CoV-2 rapid serological tests (RST) using finger prick (FP) blood on-site to evaluate their usability for exposure assessment in population-based seroprevalence studies.Study designSince cross-reactivity with common cold human coronaviruses occurs, serological testing includes a risk of false-positive results. Therefore, the selected cohort for RST-validation was based on combined immunoassay (presence of specific antibodies) and RT-qPCR (presence of SARS-CoV-2) data. RST-performance for FP blood and serum was assessed by performing each RST in two groups, namely SARSCoV- 2 positive (n=108) and negative healthcare workers (n=89). Differences in accuracy and positive and negative predictive values (PPV, NPV) were calculated for a range (1-50%) of SARS-CoV-2 prevalence estimates.ResultsThe OrientGene showed overall acceptable performance, with sensitivities of 94.4% and 100%, and specificities of 96.6% and 94.4%, using FP blood and serum, respectively. Although three RST reach optimal specificities (100%), the OrientGene clearly outperforms in sensitivity. At a SARS-CoV-2 prevalence rate of 40%, this RST outperforms the other tests in NPV (96.3%) and reaches comparable PPV (94.9%). Although the specificity of the Covid-Presto is excellent when using FP blood or serum (100% and 97.8%, respectively), its sensitivity decreases when using FP blood (76.9%) compared to serum (98.1%).ConclusionsPerformances of the evaluated RST differ largely. Only one out of five RST (OrientGene) had acceptable sensitivity and specificity using FP blood. Therefore, the latter could be used for seroprevalence studies in a high-prevalence situation. The OrientGene, which measures anti-RBD antibodies, can be valuable after vaccination as well.

Epidemiology of SARS-CoV-2 Infection Evaluated by Immunochromatographic Rapid Testing for the Determination of IgM and IgG Against SARS-CoV-2 in a Cohort of Mask Wearing Workers in the Metal-Mechanical Sector in an Area With a High Incidence of COVID-19.

Background: Although the diagnosis of new coronavirus 2019 (COVID-19) is made through the identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in respiratory secretions by means of molecular methods, a more accurate estimation of SARS-CoV-2 circulation can be obtained by seroprevalence studies. The main aim of this study was to evaluate the true epidemiology of SARS-CoV-2 infection among workers in the metal-mechanical sector who never stopped working during the pandemic period in an area with a high incidence of COVID-19 and to define whether and how they could continue the work without appreciable risks during a second wave.Methods: A total of 815 metal-mechanical workers who had never stopped working even during the pandemic period in three different factories in the Emilia-Romagna Region, Italy, and who had always used face masks during working hours, underwent a capillary blood rapid test for the determination of IgM and IgG against SARS-CoV-2 (COVID-19 IgG/IgM Rapid test, PrimaLab, Modena, Italy). In the event of a positive test, a nasopharyngeal was performed and tested for the presence of SARS-CoV-2.Results: The detection of serum IgG/IgM against SARS-CoV-2 was significantly more common among workers employed in Parma (21/345, 6.1%) than among those employed in Calerno (7/242, 2.9%) or in Spilamberto (3/228, 1.3%) (p <0.001). The analysis of the role of the different variables as predictors of seropositivity for IgG/IgM against SARS-CoV-2 revealed that the presence of specific antibodies was strictly associated with a previous history of COVID-19-like symptoms (odds ratio [OR] 3.95, 95% confidence interval [CI] 1.9–8.2) and household members with COVID-19-like symptoms (OR 2.20, 95% CI 1.04–4.82).Conclusion: This study shows that seropositivity to SARS-CoV-2 is low even among employees who did not interrupt their work during the lockdown phase in a region with a high incidence of COVID-19. The use of face masks appears effective in the avoidance of the transmission of SARS-CoV-2 in factories even in the presence of asymptomatic or mildly symptomatic workers, suggesting that work activities can continue if adequate infection control measures are used during a second wave.

Development of a Diagnostic Biosensor Method of Hypersensitivity Pneumonitis towards a Point-of-Care Biosensor.

In spite of a current increasing trend in the development of miniaturized, standalone point-of-care (PoC) biosensing platforms in the literature, the actual implementation of such systems in the field is far from being a reality although deeply needed. In the particular case of the population screenings for local or regional diseases related to specific pathogens, the diagnosis of the presence of specific antibodies could drastically modify therapies and even the organization of public policies. The aim of this work was to develop a fast, cost-effective detection method based on the manipulation of functionalized magnetic beads for an efficient diagnosis of hypersensitivity pneumonitis (HP), looking for the presence of anti-pigeon antigen antibodies (APAA) in a patient’s serum. We presented a Diagnostic Biosensor Method (DBM) in detail, with validation by comparison with a traditional high-throughput platform (ELISA assay). We also demonstrated that it was compatible with a microfluidic chip that could be eventually incorporated into a PoC for easy and broad deployment using portable optical detectors. After standardization of the different reaction steps, we constructed and validated a plastic chip that could easily be scaled to high-volume manufacturing in the future. The solution proved comparable to conventional ELISA assays traditionally performed by the clinicians in their laboratory and should be compatible with other antibody detection directly from patient samples.

Widespread Prevalence of Antibodies Against Swine Influenza A (pdm H1N1 09) Virus in Pigs of Eastern Uttar Pradesh, India.

Swine influenza virus (SIV) belongs to family Orthomyxoviridae and can cause acute respiratory infection in pigs. Several pandemic H1N1 human fatal influenza cases were reported in India. Though pigs are predisposed to both avian and human influenza virus infections with the potential to generate novel reassortants, there are only a few reports of SIV in Indian pigs. We conducted a serological survey to assess the status of H1N1 infection in pigs of various states in India, between 2009 and 2016. Based on Haemagglutination inhibition (HI) assay, seroprevalence rate of H1N1 virus ranged between 5.2% (2009) and 36.3% (2011). Widespread prevalence of antibody was observed in eastern Uttar Pradesh from 6.2 to 37.5% during the study period. Co-circulation of seasonal H1N1 virus along with pandemic H1N1 virus was indicated by the presence of specific antibodies against seasonal H1N1 virus in eastern part of Uttar Pradesh. Seroprevalence rate in pigs and influenza infection trend in human shows the possible spill over transmission of influenza to pigs from human. Hence, besides serological surveillance, continuous and systematic molecular surveillance should be implemented in pig population to reduce/quantify the risk and emergence of pandemic influenza.

Analysis of Autoantibodies against Promyelocytic Leukemia Nuclear Body Components and Biochemical Parameters in Sera of Patients with Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease characterized by immune-mediated destruction of intrahepatic bile ducts and the presence of specific antibodies. The aim of the study was to examine the diagnostic significance of antibodies against promyelocytic leukemia nuclear body (PML NB) components such as Sp100, Sp140, and PML in a cohort of PBC patients and compare the results with biochemical and histological parameters. Serum samples were collected from 93 PBC patients. Anti-Sp100 and anti-PML antibodies were assessed using commercially available kits, anti-Sp140 using developed “in-house” ELISA test. Anti-Sp140, anti-Sp100, and anti-PML antibodies were present in 25 (27%), 37 (40%), and 29 (31%) PBC patients, respectively. Anti-PML NB positive patients also showed increased concentration of bilirubin and alkaline phosphatase (p < 0.05). In the group with the presence of at least two types of these antibodies, more frequent deaths or transplantations were observed. A correlation between the presence of antibodies and histological grade (OR = 2.55 p = 0.039) was established. Patients with bilirubin > 1.1 mg/dL at the time of diagnosis had a significantly shorter time of survival than patients with bilirubin ≤ 1.1 mg/dL (HR 5.7; 95% C.I., 2.7, 12.3; p < 0.001). Our data confirm very high specificity of anti-PML NB antibodies, which can expand the laboratory diagnostic capabilities of PBC. We found an association between positive reactivity of autoantibodies directed against components of PML nuclear bodies and higher concentrations of bilirubin and alkaline phosphatase, but the main prognostic marker of survival remains serum bilirubin.

Serological Evidence of Exposure to Peste des Petits Ruminants in Small Ruminants in Rwanda.

The status of Peste des Petits Ruminants (PPR) in Rwanda is unknown, despite its prevalence in neighboring countries. A cross-sectional sampling of goats and sheep was carried out in five districts of Rwanda located closer to neighboring countries endemic to PPR. Serum samples were analyzed using a commercial ELISA, to detect antibodies to PPR virus (PPRV). Sixty-eight samples [14.8, 95% Confidence Interval (CI): 11.7–18.4] were seropositive for PPR, of which 17.4% (95% CI: 11.6–24.6; 25/144) were from sheep, whereas 13.6% (95% CI: 10.0–17.9; 43/316) were from goats. Seropositivity ranged from 8.9 to 17.3% (goats) and from 10.5 to 25.8% (sheep) in sampled districts. Seropositivity was slightly higher in males than females in both goats (15.7 vs. 12.4%) and sheep (17.7 vs. 17.1%), and were significantly marked in goats and sheep aged more than 15 months (goats: 17.9, 95% CI: 12.9–24.0; sheep: 22.2, 95% CI: 14.1–32.2) than those between 6 and 15 months (goats: 6.1, 95% CI: 2.5–12.1; sheep: 9.3, 95% CI: 3.1–20.3). Sampling was non-randomized and results are not representative of the true prevalence of PPR antibody in small ruminants. Thus, data does not allow to fully discuss the findings beyond the presence/absence certitude and the comparisons made must be interpreted with caution. The presence of specific antibodies to PPRV may, however, be linked to one or a combination of following scenarios: (1) prevalence and persistence of PPRV in sampled regions which would cause low level of clinical cases and/or mortalities that go unnoticed; (2) introduction of PPRV to herds through movements of livestock from neighboring infected countries, and/or (3) events of disease outbreaks that are underreported by farmers and veterinarians. In addition to strengthen veterinary surveillance mechanisms, further studies using robust sampling methods and integrating livestock and wildlife, should be carried out to fully elucidate PPR epidemiology in Rwanda.

A Freedom of Coxiella burnetii Infection Survey in European Bison (Bison bonasus) in Poland.

Simple SummaryQ fever is one of the important diseases transmissible from animals to humans. The source of infection can be numerous species of animals including mammals, birds, reptiles, amphibians as well as ticks. The role of wildlife in its epidemiology is poorly understood. Therefore, we examined 523 sera samples obtained from European bison for the presence of specific antibodies to assess whether infection occurs in this species and whether European bison may be an important source of infection in the natural environment as suggested by historical reports. The antibodies were found only in one free-living bull, while two other samples were doubtful. The results suggest the transmission of infection to the European bison was rather accidental and its role as an important source of infection nowadays is unlikely.Q fever is an important zoonosis caused by the intracellular Gram-negative bacteria Coxiella burnetii. The source of infection are numerous species of mammals, birds, reptiles and amphibians, as well as ticks. The disease is widespread throughout Europe, but the role of wildlife in its epidemiology is poorly understood. The European bison (Bison bonasus) population has been growing European-wide quite dynamically over the last few years. The aim of this study was to determine whether C. burnetii infection occurs in European bison and whether it can be considered an important bacterial reservoir in the natural environment. Five hundred and twenty three samples of European bison sera originating from 14 (out of the 26 existing) Polish populations were examined for the presence of specific antibodies using an ID Screen Q Fever Indirect Multi-species ELISA test. Only one (0.19%) serum sample was positive in ELISA, and two other samples were doubtful. The only seropositive animal found in this study was a free-living bull. It suggests possible transmission from domestic cattle by sharing pastures. The transmission of C. burnetii into the European bison was rather accidental in the country and its role as an important wild reservoir is unlikely. Since no tests are available for wildlife ruminants there is a need for the adaptation of the available tests.

Clinical and immunological comparisons of the results of testing for COVID-19 of employees of an outpatient medical organization of a large industrial centre during a pandemic

Aim. To determine the presence or absence of specific IgG antibodies against SARS-CoV-2 antigens in outpatient clinic staff and to compare clinical and immunological features from April to August 2020.Materials and Methods. The control group comprised 386 employees of the Novosibirsk City Clinical Polyclinic №13.The determination of IgG antibodies against SARS-CoV-2 antigens in blood serum was performed by using the ELISA method. A real time method of reverse transcription and polymerase chain reaction was used to extract RNA SARS-CoV-2 from nasopharyngeal and oropharyngeal swabs.Results. Specific IgG antibodies against SARS-CoV-2 antigens were detected in 32 (8.42%) employees of the polyclinic. Antibodies were not detected in 91.58% of employees. 9 members (28.12%) had clinical symptoms of varying degrees of disease severity in the group of employees with the presence of antibodies, 4 members of this group (12,51%) had bilateral community-acquired pneumonia with signs of COVID infection, another 5 members (15.61%) with antibodies had signs of ARVI of mild and moderate severity. RNA SARS-CoV-2 in the group of employees with the presence of antibodies and clinical implications was not detected in any case; 23 (71.88%) members with the presence of IgG-antibodies did not have clinical implications of the disease.Conclusion. The presence of specific antibodies against SARS-CoV-2 in employees with clinical implications of COVID-19 without detection of the RNA virus in the biological material is a retrospective confirmation of the etiology of the transferred infection. The detection of specific antibodies in persons who did not have clinical implications can serve as confirmation of the asymptomatic course of the transferred coronavirus infection.

LOOP-MEDIATED ISOTHERMAL AMPLIFICATION FOR DETECTION OF C. BURNETII IN BULGARIA

Q fever, which is caused by Coxiella burnetii, a small, pleomorphic intracellular bacterium, is the most widespread zoonosis in the world. The chronic form of the disease can lead to disability and death. Rapid diagnosis of Q fever is needed in order that effective treatment can be initiated. The conventional retrospective diagnosis of Q fever, based on serology, is useless for the treatment of afflicted patients. Thus, molecular methods have been created to close the diagnostic gap between the onset of the disease and the presence of specific antibodies in serum. A polymerase chain reaction is a suitable and reliable method with high sensitivity and specificity, but it requires expensive equipment and post-amplification protocol. Loop-mediated isothermal amplification (LAMP) is an isothermal technique, conducted at constant temperature that can amplify a negligible amount of DNA to more than 109 copies within one hour, using special primers and polymerase. We have tested the sensitivity and specificity of LAMP in the detection of C. burnetii. The mean positive rate of LAMP and polymerase chain reaction in patients was 100% and 74%, respectively. LAMP reacted negatively with non-C. burnetii pathogens and non-infected blood samples. We conclude that LAMP is a sensitive and specific technique for the detection of C. burnetii and has advantages over serological methods and PCR that make it attractive for diagnosing Q fever in countries around the world.

The Preparation of Convencent Plasma and Recruiting of Donors during the COVID-19 Pandemic

Background. The pandemic of the new coronavirus infection has challenged the medical community for quickly finding and implementing effective methods of treatment. In the absence of a vaccine or specific therapy with proven effectiveness, the usage of convalescent plasma can be the one of perspective methods. An important aspect of this technology is the efficient and safe preparation of convalescent plasma. To date, in the world literature there are practically no publications about donor recruitment and the specifics of the preparation of convalescent plasma.&#x0D; Purpose of the research. Presentation of the experience of organizing a workflow for recruiting donors and stockpiling of convalescent plasma with a high titer of virus-neutralizing antibodies to SARS-CoV-2.&#x0D; Methods. The analysis of the work of the Blood Service of the Moscow Department of Health for stockpiling of COVID-19 convalescent plasma has been executed. In total it has been stockpiled 1240 doses. The normative documentation has been developed by a working group on the basis of the current federal legislation of Russian federation and been approved by the Moscow Department of Health. The titer of neutralizing antibodies (VNA) has been determined as the basic method for assessing the immunological viability of convalescent plasma. The main characteristics of donors, the characteristics of the disease course, the results of preliminary testing for the presence of specific antibodies by ELISA and CLIA methods has been compared with VNA titers in the stockpiled convalescent plasma.&#x0D; Results. Due to a Moscow Health Departments order No. 325 dated 01.04.2020 (a basic local regulatory document) it has been developed a regulation for the stockpiling, examination, storage, safety and transfering of fresh frozen pathogen-reduced plasma of COVID-19 convalescent donors to medical organizations of the Moscow Health Department. For arranging an interaction with donors it has been created a call-center. For effective preliminary selection, it has been formed a donor characteristics list, which has been combined with screening of specific antibodies by ELISA and CLIA methods.&#x0D; Conclusions. Developed a system of recruiting donors and procurement process of convalescent plasma for treatment СOVID-19, which includes the necessary regulations, algorithms for the selection and recruitment of donors, the registry of donors and recipients, algorithms, efficiency and safety of convalescent plasma.

HANTAVIRUS CARDIOMYOPATHY IN A PATIENT WITH NEWLY DIAGNOSED SYSTEMIC LUPUS ERYTHEMATOSUS

SESSION TITLE: Medical Student/Resident Chest Infections Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Hantavirus infection, traditionally associated with Hantavirus Pulmonary Syndrome in critically ill adults, has been described in less severe illness with resultant cardiopulmonary consequences, particularly in strains endemic to Texas. Characterized by pulmonary infiltrates and azotemia, cardiomyopathy is a feared complication of acute disease. Systemic Lupus Erythematosus (SLE), a pathology of diffuse inflammation, may serve as a predisposition to the development of viral sequelae. CASE PRESENTATION: A 37-year-old healthy female with occupational lumber exposure presented with one week of persistent, positional and pleuritic pain and dyspnea following self-limited upper respiratory symptoms.She was afebrile and hypertensive (140/100) with tachycardia (102) and ambulatory pulse oximetry 88%. Auscultation was limited due to pain with inspiration but exam yielded no murmurs or rubs. Electrocardiogram revealed no PR or ST segment changes and CT angiogram demonstrated bilateral ground glass opacities and reactive lymphadenopathy without pulmonary embolism.Laboratory analysis returned significant for creatinine 1.28, albumin 2.7, troponin <.03, negative HIV and respiratory virus panel and normal complements. Urine studies had subnephrotic range proteinuria without casts. Serologic studies reported ANA >1:2560, elevated RNP, Rheumatoid Factor, Smith and SS-A antibodies and positive IgM testing for hantavirus. Echocardiogram verified an ejection fraction of 25-30% without pericardial effusion. Coronary and pulmonary artery catheterization were negative for ischemic heart disease or pulmonary hypertension. DISCUSSION: She was treated with colchicine, prednisone and furosemide with improvement. Given the presence of specific antibodies, negative cardiac catheterization, characteristic echocardiographic findings and clear viral trigger, the patient was clinically diagnosed with hantavirus cardiomyopathy in the setting of newly diagnosed SLE serving as a predisposition to a worsening inflammatory cascade. Due to high pretest probability and invasive nature of the procedure, endomyocardial biopsy was deferred. Ejection fraction recovered after three months following therapy with carvedilol and lisinopril. Hantavirus has been described as a precipitant of functional, often reversible, cardiomyopathy without myocardial structure disruption. Given the rapid return of cardiac function following guideline directed medical optimization, we posit a significant viral contribution. CONCLUSIONS: This case contributes to the body of literature identifying hantavirus as a cause of functional cardiomyopathy. In the setting of co-morbid SLE, it lends to the importance of considering infectious etiologies in tandem with underlying inflammatory physiology. We believe the incidence of hantavirus to be underreported and must be considered in a patient with pulmonary infiltrates, renal involvement and cardiomyopathy. Reference #1: Knust B, Rollin PE. Twenty-year summary of surveillance for human hantavirus infections, United States. Emerg Infect Dis. 2013;19(12):1934–1937 Reference #2: Fabiano P. Saggioro, Marcos A. Rossi, Maria Irma S. Duarte, Carmen Cinira S. Martin, Venâncio A. F. Alves, Marcos L. Moreli, Luis Tadeu M. Figueiredo, Jorge E. Moreira, Alessandra A. Borges, Luciano Neder, Hantavirus Infection Induces a Typical Myocarditis That May Be Responsible for Myocardial Depression and Shock in Hantavirus Pulmonary Syndrome, The Journal of Infectious Diseases, Volume 195, Issue 10, 15 May 2007, Pages 1541–1549, https://doi.org/10.1086/513874 Reference #3: Machado, A. M., De Figueiredo, G. G., Sabino dos Santos Jr, G., & Figueiredo, L. T. M. (2009). Laboratory diagnosis of human hantavirus infection: novel insights and future potential. Future Virology, 4(4), 383-389. DISCLOSURES: No relevant relationships by Molly Horstman, source=Web Response No relevant relationships by Christopher Nemeh, source=Web Response No relevant relationships by Thiennga Vo, source=Web Response

Do we have serological evidences that chilblain-like lesions are related to SARS-CoV-2? A review of the literature.

The outbreak of chilblain‐like lesions (CLL) coincidentally to the COVID‐19 pandemic is a topic of great concern. SARS‐CoV‐2 was initially hypothesized as the etiologic agent of CLL, but, since nasopharyngeal swabs seldom resulted positive, dermatologists' attention focused on the search for specific SARS‐CoV‐2 antibodies. Many papers were published contemporarily on this topic, reporting limited case series. We reviewed the English literature up to the first July 2020 and, excluding single case reports, we considered 13 studies that serologically investigated 220 patients. The presence of specific antibodies was detected in 18 subjects (8.2%): isolated IgA were found in 6 patients, IgA and IgG in 1, isolated IgG in 5, and IgM in 2. In 4 patients, isotypes were not specified. Our review demonstrated a high prevalence of negative serological results in CLL: antibodies were observed only in a few patients, that are even less excluding those with positive IgA, not clearly involved in the pathogenesis of the disease. In conclusion, although it is still uncertain whether CLL are related to SARS‐CoV‐2 infection, patients affected by CLL seem not to be prone to shedding the virus, hence, if they are asymptomatic, we can reassure them, thus avoiding hospital referral.

Human cytomegalovirus pp65 peptide-induced autoantibodies cross-reacts with TAF9 protein and induces lupus-like autoimmunity in BALB/c mice

Human cytomegalovirus (HCMV) has been linked to the triggering of systemic lupus erythematosus (SLE). We proposed that B cell epitope region of HCMV phosphoprotein 65 (HCMVpp65)422–439 mimics an endogenous antigen and initiates lupus-like autoimmunity. Amino acid homology between HCMVpp65422-439 and TAF9134-144 (TATA-box binding protein associated factor 9, TAF9) was investigated using a similarity search in NCBI protein BLAST program (BLASTP). A murine model was used to confirm their antigenicity and ability to induce lupus-like symptoms. HCMVpp65422-439 induced immune responses with the presence of specific antibodies against HCMVpp65422-439 and TAF9134-144, as well as anti-nuclear and anti-double-stranded (ds)DNA antibodies that are characteristic of SLE. In addition, the majority of HCMVpp65422-439 and TAF9134-144 immunized mice developed proteinuria, and their renal pathology revealed glomerulonephritis with typical abnormalities, such as mesangial hypercellularity and immune complex deposition. Immunoglobulin eluted from the glomeruli of HCMVpp65422-439 immunized mice showed cross-reactivity with TAF9134-144 and dsDNA. Increased anti-TAF9 antibody activity was also observed in the sera from SLE patients compared with healthy people and disease controls. Molecular mimicry between HCMVpp65 peptide and host protein has the potential to drive lupus-like autoimmunity. This proof-of-concept study highlights the mechanisms underlying the link between HCMV infection and the induction of SLE.

A study of Neospora caninum antibody seroprevalence ın dairy cows in Turkey

Neospora caninum is a intracellular protozoan parasite and is one of the major causes of repeated abortions, foetal malformations, pre-term deliveries, stillbirth and possible loss of milk yield in livestock. The presence of specific antibodies against N. caninum in the blood serum of dairy cows is investigated in the present study. A total of 184 blood serum samples of dairy cows were examined in Bursa province in the Marmara Region. N. caninum antibodies were measured using an indirect enzyme-linked immunosorbent assay (ELISA) (The Svanovir Neospora-Ab ELISA). From the total sample, antibodies to N. caninum were detected in 62 of the 184 examined cows (33.3%) and neurological findings were seen in a calf.

IMPACT OF NITRIC OXIDE SYNTHESIS MODULATORS ON THE CYTOKINES PROFILE IN EXPERIMENTAL ANTIPHOSPHOLIPID SYNDROME

Background. Antiphospholipid syndrome (APS) is an autoimmune disease characterized by the presence of specific antibodies. Objective. The aim of the study was to investigate the effect of combined use of L-arginine and aminoguanidine on cytokine profile (IL-1β, IL-6, TNF-α, IL-4, IL-10) in experimental APS. Methods. The study was performed on BALB/c female mice. L-arginine (25 mg/kg) and aminoguanidine (10 mg/kg) were used for correction. Serum cytokines concentrations were assessed using an ELISA test. Results. It was found that in APS the concentration of proinflammatory cytokines IL-1β, IL-6 and TNF-a increases in 3.2, 2.3 and 4.5 times respectively, compare to the control. At the same time a decrease of the IL-4 and IL-10 in 1.9 and 2.2 times was evidenced. Aminoguanidine, a selective iNOS inhibitor, caused a significant decrease of TNF-α by 57% (p&lt;0.001), but there were no changes in IL-1β, IL-6, IL-4 and IL-10 compare to the APS-group. L-arginine combined with aminoguanidine caused a significant decrease in the concentration of IL-1β by 30% (p&lt;0.01), IL-6 – by 16% (p&lt;0.05), TNF-a – by 59% (p&lt;0.001) compare to the control. At the same time, the concentration of IL-4 increased by 35% (p &lt;0.01), IL-10 – by 25% (p&lt;0.005). Conclusions. Combined use of the precursor of the NO synthesis L-arginine and aminoguanidine, a selective iNOS inhibitor, leads to a decrease in the concentrations of IL-1β, IL-6, TNF-a and an increase of IL-4 and IL-10 compare to the group of the BALB/c mice with APS and the group of animals administered with aminoguanidine.