scholarly journals Characterization of IgG Antibody Response against SARS-CoV-2 (COVID-19) in the Cypriot Population

2021 ◽  
Vol 10 (1) ◽  
pp. 85
Author(s):  
George Krashias ◽  
Elie Deeba ◽  
Astero Constantinou ◽  
Maria Hadjiagapiou ◽  
Dana Koptides ◽  
...  
Keyword(s):  
Marked Decrease ◽  
Herd Immunity ◽  
Steady Increase ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Second Year ◽  
Serological Data ◽  
First Time

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has hit its second year and continues to damage lives and livelihoods across the globe. There continues to be a global effort to present serological data on SARS-CoV-2 antibodies in different individuals. As such, this study aimed to characterize the seroprevalence of SARS-CoV-2 antibodies in the Cypriot population for the first time since the pandemic started. Our results show that a majority of people infected with SARS-CoV-2 developed IgG antibodies against the virus, whether anti-NP, anti-S1RBD, or both, at least 20 days after their infection. Additionally, the percentage of people with at least one antibody against SARS-CoV-2 in the group of volunteers deemed SARS-CoV-2 negative via RT-PCR or who remain untested/undetermined (14.43%) is comparable to other reported percentages worldwide, ranging anywhere from 0.2% to 24%. We postulate that these percentages reflect the underreporting of true infections in the population, and also show the steady increase of herd immunity. Additionally, we showed a significantly marked decrease in anti-NP IgG antibodies in contrast to relatively stable levels of anti-S1RBD IgG antibodies in previously infected individuals across time.

scholarly journals Prevalence of SARS-CoV-2 Infection at the University of Barcelona during the Third COVID-19 Pandemic Wave in Spain

2021 ◽  
Vol 18 (12) ◽  
pp. 6526
Author(s):  
Sebastián Videla ◽  
Aurema Otero ◽  
Sara Martí ◽  
M. Ángeles Domínguez ◽  
Nuria Fabrellas ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Venous Blood ◽  
Herd Immunity ◽  
Cross Sectional Study ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Cross Sectional ◽  
Total Prevalence ◽  
The University ◽  
The Impact

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic started in December 2019 and still is a major global health challenge. Lockdown measures and social distancing sparked a global shift towards online learning, which deeply impacted universities’ daily life, and the University of Barcelona (UB) was not an exception. Accordingly, we aimed to determine the impact of the SARS-CoV-2 pandemic at the UB. To that end, we performed a cross-sectional study on a sample of 2784 UB members (n = 52,529). Participants answered a brief, ad hoc, online epidemiological questionnaire and provided a nasal swab for reverse transcription polymerase chain reaction (RT-PCR) SARS-CoV-2 analysis and a venous blood sample for SARS-CoV-2 IgG antibody assay. Total prevalence of SARS-CoV-2 infection (positive RT-PCR or positive IgG) was 14.9% (95%CI 13.3 to 17.0%). Forty-four participants (1.6%, 95%CI: 1.2–2.1%) were positive for SARS-CoV-2 RT-PCR. IgG against SARS-CoV-2 was observed in 12.8% (95%CI: 11.6–14.1%) of participants. Overall, while waiting for population vaccination and/or increased herd immunity, we should concentrate on identifying and isolating new cases and their contacts.

scholarly journals A herd immunity to measles and rubella viruses in the population of the Republic of Serbia

2021 ◽  
Vol 11 (1) ◽  
pp. 171-176
Author(s):  
M. A. Bichurina ◽  
S. Filipovic-Vignjevic ◽  
A. Yu. Antipova ◽  
M. Bancevic ◽  
I. N. Lavrentieva
Keyword(s):  
Measles Virus ◽  
Herd Immunity ◽  
Age Groups ◽  
Age Group ◽  
Igg Antibodies ◽  
Mmr Vaccine ◽  
Igg Antibody ◽  
Group I ◽  
Study Results ◽  
The Republic

According to the WHO Strategic Plan, measles should be eradicated in 2020 in the five WHO Regions including European Region. However, large measles outbreaks are being periodically registered in diverse European countries. In the Republic of Serbia (SRB), 5,076 measles cases were detected in 2018, among which 15 cases were fatal.Aim of the study was to examine herd immunity to measles and rubella viruses in the population of the Republic of Serbia.Materials and methods. Blood serum samples obtained in 2018 and 2019 from conditionally healthy residents of the Republic of Serbia were tested for the presence of IgG antibodies to measles and rubella viruses in five age groups: I — children from 2 to 6 years old, II — children from 8 to 14 years old, III — 15 to 24 years old, IV — 25 to 49 years old and V — over 50 years old. A total of 1000 samples were obtained, 200 sera in each group. Enzygnost® Anti-Measles virus/IgG and Enzygnost® Anti-Rubella virus/IgG ELISA test systems (Siemens Healthcare Diagnostics Products GmbH, Germany) were used according to the manufacturer's instructions.Results. Overall, around 23.0% and 33.7% of the surveyed persons had no or low level of anti-measles IgG antibody (≥ 275.0 — ≤ 1000.0 IU/1). In age group I, 60% children contained no or “low” anti-measles antibodies titer (29.5% and 30.5%, respectively). In addition, low antibody titer level was mainly detected in individuals from age group II and III (p < 0.05). A third of children under 8—14 contained high IgG-antibodies titer against measles (> 3000.0 IU/l) that might serve as an evidence that such subjects recently recovered after measles. Similar results were obtained for IgG antibodies to rubella in the same age groups.Discussion. The study results evidence about altered routine immunization against measles and rubella in children aged 12—15 months (first vaccination) and those at age of 6—7 years (revaccination) with MMR vaccine. The data obtained correlate with official data on coverage with measles and rubella vaccines in the Republic of Serbia.

scholarly journals Seroepidemiological Study of Novel Corona Virus (CoVID-19) in Tehran, Iran

2021 ◽  
Author(s):  
Zeinab Tabanejad ◽  
Sorena Darvish ◽  
Zeinab Borjian Boroujeni ◽  
Seyed Saeed Asadi ◽  
Morteza Mesri ◽  
...  
Keyword(s):  
False Negative ◽  
Underlying Disease ◽  
Population Based ◽  
Immunological Methods ◽  
Age Group ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Cross Sectional ◽  
Exposed Population

AbstractA novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now spread to all countries of the world, including Iran. Although new anti-coronavirus antibodies in patients may be identified by immunological methods with sufficient sensitivity and specificity, the conclusive diagnosis of the disease is by the molecular RT-PCR process. We used a population-based seroepidemiological survey to quantify the proportion of the exposed population with SARS-CoV-2 antibodies and evaluated whether the antibodies are a marker of total or partial immunity to the proportion of the population that remains susceptible to the virus. This cross-sectional study was conducted to investigate the seroprevalence of CoVID-19 in Tehran, the capital of Iran, between April and end of October 2020. Specimens of clotted and heparinized blood (2ml) were collected from the patients. The serum and plasma were separated and stored at − 80LJ°C until use. We examined serum anti-SARS-CoV-2 IgG and IgM antibodies from 1375 in-patients admitted to our hospitals using ELISA kits. In total, 1375 participants were enrolled in this study, and SARS-CoV-2 antibodies were detected using IgM-IgG antibody assay in 291 patients. Among the seropositive patients studied, 187 were men (64.3%), and 104 were women (35.7%) (P<0.05). The mean age of the patients was 49±8.4 years; the majority (27%) were in age group 31-40 years. Also, the lowest frequency of cases was reported in the age group of 1-10 years (P <0.05). We determined the seroprevalence of SARS-CoV-2 for IgM or IgG antibodies to be 21.2%. Diabetes mellitus was the most common underlying disease among SARS-CoV-2 patients [P=0.05; Odd Ratio=1.61(0.90-2.91)]. Conventional serological assays in SARS-CoV-2 cases, such as the enzyme-linked immunoassay (ELISA) for specific IgM and IgG antibodies, have a high-throughput advantage and minimize false-negative rates that occur with the RT-PCR method. This study determined the seroprevalence of SARS-CoV-2 antibodies to be 21%. Control of diabetes among other cases factors shall play important role in management and control of COVID-19.

A Human Lymphoid Progenitor Capable of Circulating and Seeding the Thymus.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2216-2216
Author(s):  
Emmanuelle M. Six ◽  
Delphine Bonhomme ◽  
Marta Monteiro ◽  
Kheira Beldjord ◽  
Alexandrine Garrigue ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
T Cell ◽  
T Cell Development ◽  
Human Bone ◽  
Human Bone Marrow ◽  
Rt Pcr ◽  
Pcr Assay ◽  
First Time

Abstract Identification of a thymus-seeding progenitor originating from human bone marrow constitutes a key milestone in understanding and correcting defects in T-cell development. Here, we report the characterization of a novel human bone marrow lymphoid-restricted subpopulation which is part of the lineage-negative CD34+CD10+ progenitor population and which can be distinguished from B-cell-committed precursors by the absence of CD24 expression. We demonstrated that these Lin-CD34+CD10+CD24- progenitors lack myeloid and erythroid potential but can generate B, T and NK lymphocytes following culture on MS5 or OP9-hDelta1 stroma. The gene expression profile of this population, analyzed by a multiplex RT-PCR assay, revealed co-expression of RAG1, TdT, PAX5, CD3ε and IL-7Rα. These progenitors are not only present in the bone marrow but also in the blood throughout life, suggesting an ability to circulate. Moreover we showed that the Lin-CD34+CD10+CD24- cells also correspond to the most immature population of the thymus which gives rise to Lin-CD34+CD7+ T-cell precursors. Taken as a whole these findings unravel for the first time the existence of a postnatal lymphoid-restricted population which is capable of migrating from the bone marrow to the thymus.

scholarly journals The molecular characterization of the coat protein sequence and differentiation of CMV- subgroup I on tobacco from native flora in Turkey

2020 ◽  
Vol 48 (2) ◽  
pp. 523-534
Author(s):  
Mustafa USTA ◽  
Abdullah GÜLLER ◽  
Abidin GÜNAY
Keyword(s):  
Coat Protein ◽  
Sequence Similarity ◽  
Coat Protein Sequence ◽  
Rt Pcr ◽  
Plant Host ◽  
Native Flora ◽  
Subgroup Ii ◽  
Escherichia Coli Jm109 ◽  
First Time

Cucumber mosaic virus (CMV) has a broad plant-host range and a wide ecological zone distribution. Virus-like symptoms were observed on tobacco fields of Adiyaman province (Turkey) showing conspicuous mottling, greenish mosaic patterns and severe malformations of leaves. A total of forty tobacco samples tested positive against CMV by reverse transcription polymerase chain reaction (RT-PCR) using coat protein gene specific primers. Five randomly chosen CMV isolates were cloned into pGEM T-Easy vector and transformed into Escherichia coli JM109 strain. The recombinant bacterial clones containing insert-DNA were further purified and sequenced bidirectionally. In multiplex-RT-PCR studies carried out, it was found that all 40 CMV isolates belong to Subgroup I by resulting a 593 bp long DNA fragments. CMV subgroup IA was found to predominate in 4 out of 5 tobacco samples and CMV subgroup IB was found in 1 out of 5 CMV-positive samples by comparing the isolates with CMV reference isolates in phylogenetic tree. However, no Subgroup II sequences were found by multiplex RT-PCR using discriminating primers. The nucleic acid sequences were analyzed for the investigation of diversity of coat protein (CP) sequences of 5 CMV isolates. The sequence similarity ranged from 94.2-100% with the CMV subgroup I isolates infecting diverse plants in other regions of the world. The evolutionary tree revealed that the CMV IA Adiyaman isolates exhibited a genetic affinity with Australian and Spanish isolates. However, the CMV IB Adiyaman isolate showed a close genetic relationship with only the Australian isolates. To our knowledge, this study shows for the first time the occurrence of CMV IA and IB isolates infecting cultured tobacco plants in Adiyaman province.

scholarly journals Evaluation of Anti-SARS-CoV-2 IgG Antibody in Healthcare Professionals Infected with COVID-19

2021 ◽  
Vol 14 (11) ◽  
Author(s):  
Borhan Moradveisi ◽  
Shirin Behzadi ◽  
Farima Zakaryaei ◽  
Ali Jalili ◽  
Khaled Rahmani ◽  
...  
Keyword(s):  
Healthcare Professionals ◽  
Total Population ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Disease Symptoms ◽  
Positive Antibody ◽  
Antibody Titers ◽  
Polymerase Chain ◽  
And Gender

Background: The knowledge of antibody’s significance and frequency in patients cured of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is extremely limited. Objectives: This study aimed to evaluate anti-SARS-CoV-2 IgG antibodies in patients exposed to SARS-CoV-2. Methods: Healthcare professionals infected with SARS-CoV-2 were enrolled in this study. The levels of anti-SARS-CoV-2 IgG antibodies were detected 15 days after the onset of symptoms and five months later. Results: A total of 167 patients with coronavirus disease 2019 (COVID-19) were evaluated, including 119 (71.3%) females and 48 (28.7%) males. Of the 88 polymerase chain reaction (PCR)-positive patients, 55 (62.5%) had IgG-positive antibodies, and of the 79 reverse transcriptase (RT)-PCR-negative patients, 12 (16.9%) had IgG-positive antibodies. Out of 23 anosmia cases, 19 (82.6%) had positive antibodies. There was a significant relationship between anosmia and positive antibody (P  =  0.001), but there was no correlation between antibody titers and gender and other disease symptoms. Immortally, 63 (94%) cases demonstrated high levels of anti-SARS-CoV-2 IgG antibodies after five months of infection. Moreover, 6.5% (N  =  11) of the total population were re-infected with COVID-19 six months later. Conclusions: Overall, anti-SARS-CoV-2 IgG antibodies detection may be an appropriate method to identify suspected patients with a negative RT-PCR test. Antibodies can remain high in most infected patients for up to five months after infection. Moreover, anosmia seems to be a valuable diagnostic factor, and the healthcare system should implement isolation measures for patients with anosmia.

scholarly journals Changes in SARS-CoV-2 Antibody Responses Impact the Estimates of Infections in Population-Based Seroprevalence Studies

2020 ◽  
Author(s):  
Craig Fenwick ◽  
Antony Croxatto ◽  
Alix T. Coste ◽  
Florence Pojer ◽  
Cyril Andre ◽  
...  
Keyword(s):  
General Population ◽  
Acute Infection ◽  
Population Based ◽  
Antibody Responses ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Igg Antibody ◽  
S Protein ◽  
N Protein ◽  
Total Cohort

We have determined SARS-CoV-2-specific antibody responses in a cohort of 96 individuals with acute infection and in 578 individuals enrolled in a seroprevalence population study in Switzerland including three groups, i.e. subjects with previous RT-PCR confirmed SARS-CoV-2 infections (n=90), positive patient contacts (n=177) and random selected subjects (n=311). SARS-CoV-2 antibody responses specific to the Spike (S), in the monomeric and native trimeric forms, and/or the nucleocapsid (N) proteins were equally sensitive in the acute infection phase. Interestingly, as compared to anti-S antibody responses, those against the N protein appear to wane in the post-infection and substantially underestimated the proportion of SARS-CoV-2 infections in the groups of patient positive contacts, i.e. 10.9 to 32.2% reduction and in the random selected general population, i.e. up to 45% reduction. The overall reduction in seroprevalence targeting only anti-N IgG antibodies for the total cohort ranged from 9.4 to 31%. Of note, the use of the S protein in its native trimer form was more sensitive as compared to monomeric S proteins. These results indicate that the assessment of anti-S IgG antibody responses against the native trimeric S protein should be implemented to estimate SARS-CoV-2 infections in population-based seroprevalence studies.

scholarly journals Multiplexed, Microscale, Microarray-based Serological Assay for Antibodies Against All Human-Relevant Coronaviruses

2020 ◽  
Author(s):  
Erica D Dawson ◽  
Laura R Kuck ◽  
Rebecca H Blair ◽  
Amber W Taylor ◽  
Evan Toth ◽  
...  
Keyword(s):  
Vaccine Development ◽  
Clinical Performance ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Average Precision ◽  
Serum Samples ◽  
Igg Antibody ◽  
Protein Capture ◽  
Lower Limits ◽  
Microarray Format

Rapid, sensitive, and precise multiplexed assays for serological analysis during candidate COVID-19 vaccine development would streamline clinical trials. The VaxArray Coronavirus (CoV) SeroAssay quantifies IgG antibody binding to 9 pandemic, potentially pandemic, and endemic human CoV spike antigens in 2 hours with automated results analysis. IgG antibodies in serum bind to the CoV spike protein capture antigens printed in a microarray format and are labeled with a fluorescent anti-species IgG secondary label. The assay demonstrated excellent lower limits of quantification ranging from 0.3 to 2.0 ng/mL and linear dynamic ranges of 76 to 911-fold. Average precision of 11% CV and accuracy (% recovery) of 92.5% over all capture antigens were achieved over 216 replicates representing 3 days and 3 microarray lots. Clinical performance on 263 human serum samples (132 SARS-CoV-2 negatives and 131 positives based on donor-matched RT-PCR and/or date of collection) produced 98.5% PPA (sensitivity) and 100% NPA (specificity).

scholarly journals Molecular Characterization of LRB7 Gene and a Water Channel Protein TIP2 inChorispora bungeana

2016 ◽  
Vol 2016 ◽  
pp. 1-11
Author(s):  
Ming Li ◽  
Zhaoxu Liang ◽  
Cuixia Di ◽  
Weikuan Fang ◽  
Kaichao Wu ◽  
...  
Keyword(s):  
Water Channel ◽  
Integral Membrane Proteins ◽  
Rt Pcr ◽  
Major Intrinsic Protein ◽  
Channel Protein ◽  
Signature Sequence ◽  
Rapid Amplification ◽  
First Time ◽  
Water Channel Protein

Background. Water channel proteins, also called aquaporins, are integral membrane proteins from major intrinsic protein (MIP) family and involved in several pathways including not only water transport but also cell signaling, reproduction, and photosynthesis. The full cDNA and protein sequences of aquaporin inChorispora bungeanaFisch. & C.A. Mey (C. bungeana) are still unknown.Results. In this study, PCR and rapid amplification of cDNA ends approaches were used to clone the full cDNA of LRB7 (GenBank accession number: EU636988) ofC. bungeana. Sequence analysis indicated that it was 1235 bp, which had two introns and encoded a protein of 250 amino acids. Structure analysis revealed that the protein had two conserved NPA motifs, one of which is MIP signature sequence (SGxHxNPAVT), six membrane helix regions, and additional membrane-embedded domains. Phylogenetic analysis suggested that the protein was from TIP2 subgroup. Surprisingly, semiquantitative RT-PCR experiment and western blot analysis showed that LRB7 and TIP2 were only detectable in roots, unlikeArabidopsisandRaphanus. Connecting with our previous studies, LRB7 was supported to associate with chilling-tolerance inC. bungeana.Conclusion. This is the first time to characterize the full sequences of LRB7 gene and water channel protein inC. bungeana. Our findings contribute to understanding the water transports in plants under low temperatures.

Sero-molecular evaluation of Toxoplasma gondii infection among HIV-positive patients

2019 ◽  
Vol 113 (12) ◽  
pp. 771-775 ◽  
Author(s):  
Ehsan Ahmadpour ◽  
Reza Pishkarie-Asl ◽  
Adel Spotin ◽  
Hossein Samadi Kafil ◽  
Hasan Didarlu ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Mortality Rate ◽  
Hiv Positive ◽  
Igg Antibodies ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Cross Sectional ◽  
Igm Antibodies ◽  
Northwest Iran ◽  
Toxoplasma Gondii Infection

Abstract Background Toxoplasmosis is one of the most common comorbidities in HIV-positive patients with CD4+ T lymphocytes below 200 cells/μl. Early diagnosis and treatment of toxoplasmosis reduces the mortality rate in HIV-positive people. The aim of this study was to estimate the seroprevalence of Toxoplasma gondii infection in HIV-positive patients in northwest Iran using serological and molecular methods. Methods This prospective cross-sectional study included 124 HIV-positive outpatients and was conducted from January to May 2016. Anti-T. gondii IgM and IgG antibodies were detected from sera samples by chemiluminescence, while buffy coat samples were analyzed by RT-PCR for DNA detection. Patients’ socioepidemiological data were collected. Results Using chemiluminescence, 47/124 samples (37.9%) were positive for anti-Toxoplasma IgG antibodies, 2/124 samples (1.62%) were positive for IgM antibodies while 2/124 samples (1.62%) contained both IgM and IgG. There were no IgM-positive or IgG-negative patients. RT-PCR revealed four (3.22%) positive samples. On the basis of the results, a statistically significant relationship was found between anti-Toxoplasma IgG antibody seropositivity and residence (p=0.012). Conclusions The study showed a relatively low seroprevalence of anti-T. gondii IgG and IgM antibodies in HIV-positive patients in northwest Iran, while the prevalence was much higher in other regions of Iran. However, regular screening for T. gondii antibodies and early initiation of therapy are very important to decrease the mortality rate in HIV-positive patients.

Sign in / Sign up

Export Citation Format

Share Document