Defense and Immune Response to Severe Acute Respiratory Syndrome Coronavirus 2 in COVID-19 Patients: A Narrative Review

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Khwiter S ◽  
Keyword(s):  
Immune System ◽  
Vaccine Development ◽  
Antibody Test ◽  
Fold Increase ◽  
Test Method ◽  
Igg Antibodies ◽  
Serologic Test ◽  
Production Curve ◽  
Iga Production ◽  
Close Contacts

In the present review, we aim to determine the defense methods, assessment the profile of acute antibodies response in COVID-19 patients, and to provide accurate date for the usage of antibody test in clinical practice. After exposure to COVID-19, the immune system is responded in different ways and particles in different concentrations according on period of infection graduation. While the main response of immune system includes IgM, IgG and IgA antibodies, and, the most serological diagnosis tests and researches were found that “≥4- fold increase in the IgG titer” is suitable for a majority of COVID-19 patients and after three months is disappeared. IgM and IgG antibodies are the best defense methods. Serologic test method is helpful for the diagnosis of SARSCoV- 2 infection in suspects and close contacts. Antibodies determination in SARS Cov-2 is essential for COVID-19 assessment, treatment and vaccine development. In conclusion, we noticed in most of cases the production of IgM is started after 72 hrs. Of symptoms appears and peak up the production curve in 20-22 days then is disappeared in day 56 of infection. While, the production of IgG is started after 8 days of infection and peak up the production curve in 17-19 day then disappeared in day 80 of infection, but IgA production is started in 5th day of infection.

scholarly journals Antibody responses to SARS-CoV-2 in COVID-19 patients: the perspective application of serological tests in clinical practice

2020 ◽  
Author(s):  
Quan-xin Long ◽  
Hai-jun Deng ◽  
Juan Chen ◽  
Jie-li Hu ◽  
Bei-zhong Liu ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Antibody Response ◽  
Antibody Test ◽  
Fold Increase ◽  
Rt Pcr ◽  
Serological Tests ◽  
Positive Rate ◽  
Sequential Samples ◽  
Close Contacts

AbstractBackgroundWe aim to investigate the profile of acute antibody response in COVID-19 patients, and provide proposals for the usage of antibody test in clinical practice.MethodsA multi-center cross-section study (285 patients) and a single-center follow-up study (63 patients) were performed to investigate the feature of acute antibody response to SARS-CoV-2. A cohort of 52 COVID-19 suspects and 64 close contacts were enrolled to evaluate the potentiality of the antibody test.ResultsThe positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of seroconversion for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion. The criteria of ‘IgG seroconversion’ and ‘> 4-fold increase in the IgG titers in sequential samples’ together diagnosed 82.9% (34/41) of the patients. Antibody test aided to confirm 4 patients with COVID-19 from 52 suspects who failed to be confirmed by RT-PCR and 7 patients from 148 close contacts with negative RT-PCR.ConclusionIgM and IgG should be detected simultaneously at the early phase of infection. The serological diagnosis criterion of seroconversion or the ‘>; 4-fold increase in the IgG titer’ is suitable for a majority of COVID-19 patients. Serologic test is helpful for the diagnosis of SARS-CoV-2 infection in suspects and close contacts.

scholarly journals Learning the language of viral evolution and escape

Science ◽  
2021 ◽  
Vol 371 (6526) ◽  
pp. 284-288 ◽  
Author(s):  
Brian Hie ◽  
Ellen D. Zhong ◽  
Bonnie Berger ◽  
Bryan Bryson
Keyword(s):  
Immune System ◽  
Natural Language ◽  
Vaccine Development ◽  
Sequence Data ◽  
Viral Evolution ◽  
Machine Learning Algorithms ◽  
Language Models ◽  
Viral Escape ◽  
Human Immune System ◽  
Influenza Hemagglutinin

The ability for viruses to mutate and evade the human immune system and cause infection, called viral escape, remains an obstacle to antiviral and vaccine development. Understanding the complex rules that govern escape could inform therapeutic design. We modeled viral escape with machine learning algorithms originally developed for human natural language. We identified escape mutations as those that preserve viral infectivity but cause a virus to look different to the immune system, akin to word changes that preserve a sentence’s grammaticality but change its meaning. With this approach, language models of influenza hemagglutinin, HIV-1 envelope glycoprotein (HIV Env), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike viral proteins can accurately predict structural escape patterns using sequence data alone. Our study represents a promising conceptual bridge between natural language and viral evolution.

The role of coinfection with influenza viruses in the pathogenesis of severe infection in patients with COVID-19

2021 ◽  
Vol 21 (3) ◽  
pp. 159-164
Author(s):  
Tamara N. Shvedova ◽  
Olga S. Kopteva ◽  
Polina A. Kudar ◽  
Anna A. Lerner ◽  
Yuliya A. Desheva
Keyword(s):  
Influenza A ◽  
Fold Increase ◽  
Igg Antibodies ◽  
C Reactive Protein ◽  
S Protein ◽  
Neutrophil Lymphocyte Ratio ◽  
Lymphocyte Ratio ◽  
Reactive Protein ◽  
Coronavirus Infection

BACKGROUND: Despite the continuing global spread of the coronavirus infection COVID-19 caused by the SARS-CoV-2 coronavirus, the mechanisms of the pathogenesis of severe infections remain poorly understood. The role of comorbidity with other seasonal viral infections, including influenza, in the pathogenesis of the severe course of COVID-19 remains unclear. MATERIALS AND METHODS: The present study used sera left over from ongoing laboratory studies of patients with varying degrees of severity of COVID-19. The study was approved by the Local Ethics Committee of the Federal State Budgetary Scientific Institution IEM (protocol 3/20 from 06/05/2020). We studied 28 paired samples obtained upon admission of patients to the hospital and after 57 days of hospital stay. Paired sera of patients with COVID-19 were tested for antibodies to influenza A and B viruses. The presence of IgG antibodies specific to the SARS-CoV-2 spike (S) protein was studied using an enzyme-linked immunosorbent assay (ELISA). The serum concentration of C-reactive protein and the neutrophil-lymphocyte ratio on the day of hospitalization were also assessed. RESULTS: At least a 4-fold increase in serum IgG antibodies to SARS-CoV-2 S protein was found both in patients with PCR-confirmed SARS-CoV-2 infection and without PCR confirmation. It was shown that out of 18 patients with moderate and severe forms of COVID-19 infection, six of them showed at least a 4-fold increase in antibodies to influenza A/H1N1, in one to influenza A/H3N2 and in two cases to the influenza B. Laboratory data in these two groups were characterized by significant increases in serum C-reactive protein and neutrophil-lymphocyte ratio concentrations compared with the moderate COVID-19 group. CONCLUSIONS: Serological diagnostics can additionally detect cases of coronavirus infection when the virus was not detected by PCR. In moderate and severe cases of COVID-19, coinfections with influenza A and B viruses have been identified. The results obtained confirm the need for anti-influenza immunization during the SARS-CoV-2 pandemic. Influenza virus screening can significantly improve patient management because recommended antiviral drugs (neuraminidase inhibitors) are available.

scholarly journals SARS-CoV-2 Immunoglobulin g (IgG) Kinetics in Healthcare Workers and Their Close Contacts Reduced Risk of Re-infection: South-East Asian Region

2021 ◽  
Author(s):  
Mradul Kumar Daga ◽  
Govind Mawari ◽  
Vijay Kumar Karra ◽  
Meghachandra Singh ◽  
Siddharth Chand ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Healthcare Workers ◽  
Close Contact ◽  
Antibody Test ◽  
New Delhi ◽  
Igg Antibody ◽  
Symptomatic Infection ◽  
Medical College ◽  
Reduced Risk ◽  
Close Contacts

Abstract BackgroundSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for global pandemic, and it has caused more than 2.3 million deaths. Persistence and stability of immunoglobulin G (IgG) response after recovery from COVID-19 infection is still uncertain. MethodsWe performed a longitudinal cohort study in healthcare workers (HCW) and their close contacts (Non-HCW) with known resolved SARS-CoV-2 infection and undiagnosed infection at Maulana Azad Medical College and associated Lok Nayak hospital, New Delhi. Baseline IgG antibody titers was determined and the participants were followed over a period of six months. We also examined relationship between SARS-CoV-2 immunoglobulin G (IgG) response and new symptomatic infection in HCW and Non-HCW over time. Results176 (70.9%) healthcare workers and 72 (29.0%) non-healthcare workers were recruited from two cohorts. 82 subjects recovered from SARS-CoV-2 infection and 166 undiagnosed for the infection having history of close contact with COVID-19 patients were followed up for a median of 227 days (interquartile range, 166 to 202) after a positive IgG antibody test. In the recovered subjects 70.7% (58) were seropositive for first anti-spike IgG assay at baseline, followed by 80.0%, 90.6% and 82.6% at three visits respectively. In undiagnosed subjects 37.3% (62) were seropositive at baseline, followed by 70.9%, 75.8% and 82.2% respectively. Also, 46.8% (29) were asymptomatic with no symptoms of COVID-19 and were seropositive at baseline. However, presence of IgG antibodies was associated with substantial reduced risk of re-infection over the follow up duration.ConclusionOur data showed that the antibodies levels measured increased over the first three months and decreased slightly after that and remained at a plateau and relatively stable for at least a period of six months.

The Organophosphate Paraoxon Has No Demonstrable Effect on the Murine Immune System following Subchronic Low Dose Exposure

2008 ◽  
Vol 21 (4) ◽  
pp. 891-901 ◽  
Author(s):  
M.J. Fernandez-Cabezudo ◽  
S. Azimullah ◽  
S.M. Nurulain ◽  
M. Mechkarska ◽  
D.E. Lorke ◽  
...  
Keyword(s):  
Body Weight ◽  
Immune System ◽  
Ache Activity ◽  
Body Weight Gain ◽  
Fold Increase ◽  
Spleen Weight ◽  
Host Immune System ◽  
Immunological Parameters ◽  
Subchronic Exposure ◽  
Significant Difference

Paraoxon is the bioactive metabolite of the organophosphate pesticide parathion. Desulphuration of parathion by liver enzymes or sunlight results in the formation of paraoxon which inhibits acetylcholine esterase (AChE) activity. In the present study, we analyzed the effect of a 6-week, subchronic treatment with two different daily intraperitoneal doses (30 or 40 nmol) of paraoxon on the immune system of BALB/c mice. At a dose of 30 nmol/day, body weight of treated animals was unchanged compared to the controls. In contrast, the higher dose (40 nmol/day) induced a reduction in body growth, particularly in the first 3 weeks of treatment, peaking at week 2 when the saline group showed a 14.2-fold increase in body weight gain compared to paraoxon-treated animals. Moreover, mice treated with either dose of paraoxon had a >50% reduction in AChE activity during the first 3 weeks of treatment, but by the end of the treatment (week 6), AChE activity returned to normal. With regard to immunological parameters, there was no significant difference in either total spleen weight or in the ratios of various spleen cell populations between control and paraoxon-treated animals. Furthermore, no changes were observed in mitogen-induced cytokine secretion from splenocytes of paraoxon-treated mice. Finally, subchronic exposure to paraoxon did not alter mortality of mice exposed to a bacterial infection with Salmonella typhimurium. These data suggest that although subchronic exposure to paraoxon induced a transient inhibition in AChE activity, it had no demonstrable effect on the host immune system.

scholarly journals Investigation of Borrelia burgdorferi antibodies in patients with multiple sclerosis

2020 ◽  
Vol 11 (2) ◽  
pp. 21-24
Author(s):  
Nilay Ildız ◽  
İbrahim Halil Özerol ◽  
A. Cemal Özcan ◽  
Hamit Çelik
Keyword(s):  
Multiple Sclerosis ◽  
Borrelia Burgdorferi ◽  
Viral Infections ◽  
Antibody Test ◽  
Elisa Test ◽  
Igg Antibodies ◽  
Number Of Patients ◽  
Seroprevalence Data ◽  
Significant Difference ◽  
Antibody Positivity

Background: Lyme is a disease that is non-compulsory in our country and whose seroprevalence data is less studied. Aims and Objective: Recent studies have shown that bacterial and viral infections are risk factor for various neurodegenerative diseases such as multiple sclerosis and Alzheimer’s disease. Herein, we aim to determine the seroprevalence of Lyme in multiple sclerosis (MS) patients. For this purpose, 100 MS patient’s serums were investigated for Borrelia burgdorferi IgM and IgG positivity. Materials and Methods: The results identified with ELISA as positive antibody was confirmed by Western Blot (WB) test. The correlation between ages, gender, occupation, tick history, existence of erythema chronicum migrans (ECM), antibody positivity, pain, year with MS results were investigated using Kolmogorov-Smirnow and Kruskal-Wallis statistical test. Results: B. burgdorferi IgM and IgG antibodies were positive in 8% patients when using ELISA method, but that were found to be 2% by WB. ELISA IgM antibody test gave a 5 negative result in WB. These results were considered false positive in the ELISA test. So, altogether 5 patients were positive by WB method. None of syphilis positive samples detected that B. burgdorferi positive serum. A significant difference between the parameters in terms of IgM positivity was not detected (p> 0.05). B. burgdorferi IgG antibodies were found significant differences between the MS disease duration (p = 0.03). MS in the group of less than 10 years had higher titers of IgG antibodies to B. burgdorferi. Conclusion: Although a small number of patients with MS is positive with Lyme antibodies. Lyme disease is a treatable.Also, If the patient is MS, clinician should be considered Lyme in the differential diagnosis. This is the first study that the correlation between Lyme and MS from Turkey.

The mucosal immune system: from fundamental concepts to vaccine development

Vaccine ◽  
1992 ◽  
Vol 10 (2) ◽  
pp. 75-88 ◽  
Author(s):  
Jerry R. McGhee ◽  
Jiri Mestecky ◽  
Mark T. Dertzbaugh ◽  
John H. Eldridge ◽  
Masatomo Hirasawa ◽  
...  
Keyword(s):  
Immune System ◽  
Vaccine Development ◽  
Mucosal Immune System

scholarly journals Downmodulation of Vaccine-Induced Immunity and Protection against the Intracellular BacteriumFrancisella tularensisby the Inhibitory Receptor FcγRIIB

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Brian J. Franz ◽  
Ying Li ◽  
Constantine Bitsaktsis ◽  
Bibiana V. Iglesias ◽  
Giang Pham ◽  
...  
Keyword(s):  
Vaccine Development ◽  
Immune Protection ◽  
Fc Gamma Receptor ◽  
Gamma Receptor ◽  
Significant Difference ◽  
Cytokine Levels ◽  
Iga Production ◽  
Protection Against Infection ◽  
The Impact

Fc gamma receptor IIB (FcγRIIB) is the only Fc gamma receptor (FcγR) which negatively regulates the immune response, when engaged by antigen- (Ag-) antibody (Ab) complexes. Thus, the generation of Ag-specific IgG in response to infection or immunization has the potential to downmodulate immune protection against infection. Therefore, we sought to determine the impact of FcγRIIB on immune protection againstFrancisella tularensis(Ft), a Category A biothreat agent. We utilized inactivatedFt(iFt) as an immunogen. Naïve and iFt-immunized FcγRIIB knockout (KO) or wildtype (WT) mice were challenged withFt-live vaccine strain (LVS). While no significant difference in survival between naïve FcγRIIB KO versus WT mice was observed, iFt-immunized FcγRIIB KO mice were significantly better protected than iFt-immunized WT mice.Ft-specific IgA in serum and bronchial alveolar lavage, as well as IFN-γ, IL-10, and TNF-αproduction by splenocytes harvested from iFt-immunized FcγRIIB KO, were also significantly elevated. In addition, iFt-immunized FcγRIIB KO mice exhibited a reduction in proinflammatory cytokine levelsin vivoat 5 days after challenge, which correlates with increased survival followingFt-LVS challenge in published studies. Thus, these studies demonstrate for the first time the ability of FcγRIIB to regulate vaccine-induced IgA production and downmodulate immunity and protection. The immune mechanisms behind the above observations and their potential impact on vaccine development are discussed.

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