Immunoglobulin G Antibodies Research Articles

Detection of Toxoplasmosis in Pregnant Women’s In Sabratha City of Using VIDS

Toxoplasmosis is usually asymptomatic, but can have severe consequences if It occurs in immunodeficient subject or fetuses. The diagnosis of toxoplasmosis during pregnancy is often based on maternal serological testing for IgM and IgG Anti- Toxoplasma antibodies. Persistence of IgM for long periods, posses' problems in distinguishing acute from chronic infection. The evaluation of specific IgG avidity enables more accurate dating, since avidity rises progressively during the course of infection. Test that measures immunoglobulin G (IgG) is used to determine if a person has been infected. If it is necessary to try to estimate the time of infection, which is of particular importance for pregnant women, a test which measures immunoglobulin M (IgM) is also used along with other tests such as an avidity test. Toxoplasma-specific IgG antibodies are detectable 1-3 weeks after infection and remain detectable for the life of the individual. Toxoplasma-specific IgM antibodies are also detectable 1-3 weeks after infection but generally decline to nil by one year after infection. The VIDAS® TOXO IgM (TXM) assay is intended for use on the instruments of the VIDAS family (VITEK® Immunodiagnostic Assay System) as an automated enzyme-linked fluorescent immunoassay (ELFA) for the presumptive qualitative detection of anti-Toxoplasma gondii IgM antibodies in human serum. Seventy-six (76) women in the first 16 weeks of pregnancy were tested for VIDAS IgM, IgG antibodies and VIDAS Toxo-IgG avidity. Low avidity antibodies were demonstrated in 2 (33.3%) of 6 sera positive with IgM assay and 4 (12.12%) of sera positive with IgG assay. Low avidity was also detected in 2 (3.27%) of 61 sera negative with IgM. The low avidity suggesting a recent infection, while high avidity in 3 (50%) of the 6 positive IgM and 24 (72.72%) of 33 positive IgG indicating that the Infection acquired in the distant past. These findings highlight the value of VIDAS IgG avidity when used in combination with the VIDAS IgM and IgG assays to provide a confirmatory evidence of an acute infection with a single serum specimen for pregnant women.

Seroprevalence and Potential Risk Factors of Toxocariasis among General Population in Southwest Iran: Implications on the One Health Approach.

Toxocariasis is one of the most common zoonotic diseases distributed worldwide. This study aimed to estimate the seroprevalence of anti-Toxocara immunoglobulin G (IgG) antibodies and the associated risk factors among general populations living in urban and rural areas of Abadan and Khorramshahr cities in Khuzestan Province, Southwest Iran. This cross-sectional study was conducted between March and September 2022. There were 363 participants (190 females and 173 males) aged from <20 to ≥60 years old. Anti-Toxocara IgG antibodies in serum samples were measured using a commercially available enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was employed to collect information regarding sociodemographic status and probable risk factors associated with toxocariasis. It was found that the seroprevalence rate in males (15.0%, 95% CI = 10.47-21.11) was higher than in females (10.5%, 95% CI = 6.92-15.70). Moreover, we observed that the seroprevalence was higher in participants at younger ages compared to other age ranges (COR = 2.55, 95% CI = 0.92-7.12, p =0.073). The findings of the univariate analysis revealed that residency in rural areas (p < 0.001), using unpurified water (p < 0.001), contact with dog (p =0.002), contact with soil (p < 0.001), consumption of improperly washed vegetables (p < 0.001), and history of drinking untreated water (p < 0.001) were risk factors associated with toxocariasis. Further comprehensive studies with a focus on humans and animals should be designed in different areas of the Province. The data represented by the current study are useful to health policymakers to consider precise surveillance and effective prevention measures to control this zoonotic infection among general populations.

LIPOSOMAL DELIVERY OF IMMUNOMODULATORY ANTIGEN OF B. MALAYI: ISOLATION, PREPARATION, CHARACTERIZATION, AND IMMUNE RESPONSES ASSESSMENT

Objective: The present study was aimed on developing and characterizing liposomal delivery system loaded with antigen of filaria parasite Brugia malayi extracted protein for assessment of humoral immune responses of antigen. Methods: Liposomes were prepared by reverse-phase evaporation method with slight modification using molar ratio of Soya PC: PE:Cholesterol in different molar concentrations. Results: The levels of F6 specific immunoglobulin (Ig) G1, IgG2a and IgG2b antibodies were found to be elevated in immunized animals over non-immunized controls. Analysis of IgG-subclasses revealed that all the subclasses at (1:25dilution) increased several folds over the controls with IgG1 showing the greatest increase (25.0-fold) followed by IgG2b (3.0-fold). Antibodies titers showed the many fold increment of titers on liposomized antigen groups (Gr.I; without booster dose and Gr.IV; with booster dose). IgG showed about 2.2 fold increment in Gr.IV than control group (Gr.V). IgG1 after booster dose showed about 25-fold increment followed by IgG2b than IgG2a. Conclusion: These results suggest that the liposomal antigen delivery system shows 25-fold IG-G responses in comparison to plain administrated antigen.

Have we attended herd immunity against COVID? A cross-sectional analytical study of seroprevalence among blood donors

Abstract BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (COVID-19) is one of the worst health-care problem humankind has faced in the last few centuries. Understanding the population’s antibody responses is crucial for effective decision-making while implementing public health interventions in view of the COVID-19 pandemic. The study was done to know the immune status of healthy donors to COVID-19 infections and to know the duration of persistence of immunoglobulin G (IgG) antibodies with respect to infections and vaccination. AIMS: This study aimed to determine the prevalence of SARS-CoV-2 IgG antibodies in healthy blood donors in our tertiary care center. MATERIALS AND METHODS: This was a cross-sectional analytical study conducted for a period of 1 year in our blood center. Our study had a sample size of 809 healthy blood donors. Samples of the first 81 donors of each month were chosen. Donor details such as previous COVID positivity, symptoms, hospitalization, comorbidities, contact history, and vaccination status were collected using a structured questionnaire. A 5-ml sample was collected and was tested using Qualisa COVID-19 IgG enzyme-linked immunosorbent assay detection kits. The antigens used for coating the kits were recombinant antigens representing SARS-CoV-2 S1 protein. Data were analyzed using SPSS version 21. The prevalence of positive IgG seroprevalence of COVID-19 antibodies was reported using proportion along with 95% confidence interval. Association between all the categorical variables and the presence of seropositive status for IgG antibodies was assessed using the Chi-square test. P &lt;0.05 was considered statistically significant. RESULTS: The seroprevalence of COVID-19 antibodies in our study participants was 82.3%. There is a significant association between COVID-19 infectivity, vaccination, with seroprevalence. There was a seropositivity of 51% among those who were neither infected nor vaccinated, which may be due to the development of herd immunity in our population. CONCLUSIONS: Population who were neither vaccinated nor had a history of infection also had a significant prevalence of antibodies suggesting the development of herd immunity in our community. The present study will add to the knowledge and better understanding of COVID-19 antibodies in the existing literature. Further studies will be required to verify our findings and to know the persistent nature of COVID antibodies.

Determination of SARS-CoV-2 IgG antibody levels in hematology-oncology patients after COVID-19 vaccination.

Cancer patients are among the high-risk groups where COVID-19 infection tends to be severe and can lead to increased mortality. Therefore, they are included in the priority groups for COVID-19 vaccination. This study aimed to compare the levels of SARS-CoV-2 immunoglobulin G (IgG) antibodies following two different COVID-19 vaccinations between hematology-oncology patients and healthcare personnel and to identify factors associated with these antibody levels. A prospective study was conducted with 91 hematology-oncology patients (cancer group) and 75 healthcare personnel (control group) from January 2020 to June 2023. The cancer and control groups comprised adults who had received a booster dose, with either a single dose of BNT162b2 or two doses of CoronaVac™ spaced one month apart, following their primary vaccination with two doses of either CoronaVac™ or BNT162b2. Four weeks after the administration of the booster dose, levels of SARS-CoV-2 IgG antibodies were assessed using an ELISA kit. Antibody levels above 50 AU/mL were accepted as signifying seropositivity. The median SARS-CoV-2 IgG antibody level was lower in the cancer group compared to the control group (4,509 vs. 7,268, p = 0.004), while the rate of seroconversion was similar between the groups (97.8% vs. 100%, p = 0.564). In the cancer group, no association was found between SARS-CoV-2 IgG antibody levels and age, sex, comorbidity, type of malignancy, stage and duration, or type of vaccine. In cancer patients, the seroconversion positivity rate was about 98%. However, antibody responses were still lower compared to the control group. No difference was detected in antibody levels among cancer patients based on the type of vaccine.

Detection of Chlamydial Heat Shock Protein 60 and 10 Antibody among Female Infertility.

Of the many sexually transmitted pathogens, Chlamydia trachomatis is increasingly being associated with long-term sequelae such as infertility, apart from causing genital tract infections. Many inflammatory responses directed against chlamydial infection can cause tubal damage resulting in infertility. For example, chlamydial heat shock protein 60 (cHSP60) and cHSP10 along with humoral immune response. The aim of our study is to detect the presence of immunoglobulin G (IgG) antibodies against Major Outer Membrane Protein (MOMP), cHSP60, and cHSP10 among female infertility. A total number of 230 female infertility patients attending the Outpatient Department of Reproductive Medicine, SRIHER, were included in the study. Detailed history documented in the proforma. Serological detection of C. trachomatis IgG antibody against MOMP, cHSP60, and cHSP10 antibody was done by enzyme-linked immunosorbent assay (ELISA). C. trachomatis IgG antibody against MOMP was detected in 15 (6.5%) of 230 females. High seropositivity to cHSP60 antibodies was detected among females of tubal factor infertility (TFI). Our study showed that cHSP60 antibodies (3.4%) were more common than cHSP10 (2.6%). Our study suggest cHSP60 or cHSP10 antibody detection by ELISA along with TFI is helpful for diagnosis and early institution of therapy. The accuracy of TFI prediction could be increased by the detection of anti-MOMP and cHSP60 over cHSP10 among secondary infertility than primary. The most probable reason for high seropositivity among secondary infertility patients may be due to repeated infection and chronicity because of longer active sexual life.

Impact of structural modifications of IgG antibodies on effector functions.

Immunoglobulin G (IgG) antibodies are a critical component of the adaptive immune system, binding to and neutralizing pathogens and other foreign substances. Recent advances in molecular antibody biology and structural protein engineering enabled the modification of IgG antibodies to enhance their therapeutic potential. This review summarizes recent progress in both natural and engineered structural modifications of IgG antibodies, including allotypic variation, glycosylation, Fc engineering, and Fc gamma receptor binding optimization. We discuss the functional consequences of these modifications to highlight their potential for therapeutical applications.

Safety and Efficacy of Inactivated SARS-CoV-2 Vaccine in Patients with Rheumatic Diseases and Serum Antibody Changes Post-Omicron Variant Infection.

The purpose of this study was to investigate whether the inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine has a similar effectiveness and safety profile in patients with rheumatic and musculoskeletal diseases (RMDs) and healthy controls (HCs). Between August 10, 2021 and September 30, 2021, 134 HCs and 269 patients with RMDs were recruited. All participants who tested negative for COVID-19 were vaccinated with SARS-CoV-2 inactivated vaccine. Next, 150 patients with RMDs and 30 HCs infected with the SARS-CoV-2 Omicron variant within the previous 12weeks were recruited between February 20, 2023 and March 1, 2023. Serum samples were collected from each participant, and the serum immunoglobulin G (IgG) and immunoglobulin M (IgM) antibody titers against SARS-CoV-2 were determined using a chemiluminescence assay. No statistically significant difference was found in the titer of anti-SARS-CoV-2 IgG and IgM antibodies, or in the incidence of vaccination-related adverse events between the RMD and HC groups (P = 0.183, P = 0.903, and P = 0.27, respectively). Serum IgG titers of SARS-CoV-2 neutralizing antibodies were significantly higher in patients who received two or more doses of inactivated vaccine than in patients who were unvaccinated or had received one dose of vaccine (244.36 ± 109.79 vs. 66.20 ± 82.50; P < 0.001). SARS-CoV-2 inactivated vaccines have similar protective effects in HCs and patients with RMDs, with an appreciable safety profile. Fully vaccinated patients with RMDs infected with the Omicron variant were able to produce effective neutralizing antibody concentrations.

Seroprevalence of Chlamydia trachomatis among Infertile Female Patients : A Cross-sectional Study

Introduction: Among many sexually transmitted pathogens, Chlamydia trachomatis (C.trachomatis) is increasingly being connected with long-term sequelae like infertility, in addition to its ability to cause genital tract infection. Aim: To determine the seroprevalence of C.trachomatis Infection (CTI) among the infertile female patients at a tertiary care centre. Materials and Methods: This was a cross-sectional study conducted from March 2019 to February 2020 at the Outpatient Department (OPD) of Reproductive Medicine and Surgery, Sri Ramachandra Hospital, SRIHER, Chennai, Tamil Nadu, India. Women with primary and secondary infertility were included in the study and their clinical history was collected in a proforma. Estimation of Immunoglobulin G (IgG) antibody by Enzyme Linked Immunosorbent Assay (ELISA) to C.trachomatis was done in the patient’s serum. Results: Out of the 130 female patients with infertility, 10 (7.6%) of them were positive for C.trachomatis IgG antibody. Among the 10 patients, five were primary infertility and the rest were secondary infertility. The most common risk factors were lack of awareness of contraceptive usage, young age, use of Intrauterine Device (IUD) and multiple sexual partners were generally associated with genital Chlamydial infection. Conclusion: The prevalence of C.trachomatis was 7.6% in the present study and was found to vary based upon the culture, hygiene and education. Hence, the present study recommends screening of IgG antibody by ELISA for C.trachomatis, which plays a significant role in the diagnosis of infertility.

A Case of Celiac Disease with Pericardial Effusion

Celiac disease is a unique enteropathic immune disorder and is now considered a distinct disease entity with protein manifestation and worldwide distribution. The deposition of immune complexes in the small intestine could be a possible reason for the extraintestinal autoimmune manifestations of Celiac disease. Pericardial effusion, though rare in adults, is likely a result of these autoimmune disorders related to Celiac disease. In present study case report, the authors present the case of a 67-year-old female patient with generalised oedema, anasarca, and pitting oedema in the lower extremities. Due to multiple episodes of vomiting, upper gastrointestinal endoscopy was performed, which revealed atrophic duodenal mucosa, and duodenal biopsies were taken from the second part of the duodenum (D2 biopsies). The possibility of Celiac disease was considered, and anti-deamidated gliadin peptide, Immunoglobulin A (IgA), and Immunoglobulin G (IgG) antibodies were sent. Celiac disease was diagnosed based on elevated serum levels of anti-deamidated gliadin peptide, IgA, and IgG antibodies, as well as histologic findings in the small bowel (duodenal biopsies D2). During the thorough evaluation, pericardial effusion was incidentally detected. Celiac disease is an autoimmune disorder in which exposure to gluten triggers inflammation in genetically predisposed individuals. The illness is estimated to have a prevalence of 2%, and most affected people remain undiagnosed. Pericardial effusion is a possible manifestation of Celiac disease, but there is currently no evidence that the disease directly causes the effusion.

A Case of Celiac Disease with Pericardial Effusion

Celiac disease is a unique enteropathic immune disorder and is now considered a distinct disease entity with protein manifestation and worldwide distribution. The deposition of immune complexes in the small intestine could be a possible reason for the extraintestinal autoimmune manifestations of Celiac disease. Pericardial effusion, though rare in adults, is likely a result of these autoimmune disorders related to Celiac disease. In present study case report, the authors present the case of a 67-year-old female patient with generalised oedema, anasarca, and pitting oedema in the lower extremities. Due to multiple episodes of vomiting, upper gastrointestinal endoscopy was performed, which revealed atrophic duodenal mucosa, and duodenal biopsies were taken from the second part of the duodenum (D2 biopsies). The possibility of Celiac disease was considered, and anti-deamidated gliadin peptide, Immunoglobulin A (IgA), and Immunoglobulin G (IgG) antibodies were sent. Celiac disease was diagnosed based on elevated serum levels of anti-deamidated gliadin peptide, IgA, and IgG antibodies, as well as histologic findings in the small bowel (duodenal biopsies D2). During the thorough evaluation, pericardial effusion was incidentally detected. Celiac disease is an autoimmune disorder in which exposure to gluten triggers inflammation in genetically predisposed individuals. The illness is estimated to have a prevalence of 2%, and most affected people remain undiagnosed. Pericardial effusion is a possible manifestation of Celiac disease, but there is currently no evidence that the disease directly causes the effusion.

Clinical Significance of IgG4 Serum Concentration in Graves' Disease.

Elevated immunoglobulin G4 (IgG4) serum antibodies are an important feature of IgG4-related disease. However, IgG4 antibodies can play a role in autoimmune thyroid disorders. In this study, we aimed to evaluate the impact of serum IgG4 levels on clinical features of Graves' disease (GD). We recruited 60 patients with GD (48 patients without thyroid eye disease, 12 patients with moderate-to-severe Graves' orbitopathy [GO], and 25 healthy control subjects). The prevalence of high IgG4 serum concentration was 4.2% among GD patients without GO and 33.33% in patients with moderate-to-severe GO. The group with GO had significantly higher median IgG4 levels (87.9 mg/dL) than the control group (41.2 mg/dL, P = 0.034) and the GD without GO group (30.75 mg/dL, P < 0.001). Patients with thyroid nodules had lower IgG4 levels than patients without thyroid nodules, but the difference was not statistically significant (35.7 [24.8; 41.53] mg/dL vs. 43 [30.1; 92.7] mg/dL, P = 0.064). IgG4 as a diagnostic tool for moderate-to-severe GO had the following parameters: area under the curve (AUC): 0.851 (P < 0.001), at the cut-off value of 49 mg/dL, negative predictive value: 100%, positive predictive value: 48%, sensitivity: 100%, specificity: 73%. There were no significant differences between the high and normal IgG4 groups in thyroid hormones, antithyroid antibodies, and ultrasound features. Serum IgG4 levels are associated with some of the clinical features of GD and can help in the diagnostic process of the disease. More research is needed to better understand the pathophysiology of IgG4 involvement in GD.

Survey of the present health & nutritional status of Shompen tribe of Great Nicobar Island.

Shompens are one of the two mongoloid tribes of Nicobar district. There is little information about their recent health status since the last survey which was conducted in 1998. Hence, a comprehensive health and nutritional survey was conducted in March 2017 to assess the changes. The survey was carried out by a joint team of various organizations including the ICMR-Regional Medical Research Centre and Tribal Welfare and Health Department both located in Port Blair. A detailed health and nutrition survey of the Shompen community was planned by deputing a field research team. The survey included demographic data, anthropometric data, clinical examination, screening for the markers of infectious diseases, respiratory pathogens, tuberculosis and haemoglobinopathies. About half of the Shompen adults (both males and females) had a body mass index (BMI) of ≥23. However, Shompen children had a good nutritional status with no child suffering from undernutrition. As per BMI for age, none of the children <5 yr were under-nourished, while in the 5-17 yr group, 12 per cent of children were undernourished. Anaemia prevalence was about 48.3 per cent, with 54 per cent prevalence in females and 43.8 per cent in males. Fungal infection of the skin, acute respiratory infection and abdominal pain were the common morbidities observed. None had active pulmonary tuberculosis. Of 38 Shompens screened for IgG (immunoglobulin G) antibodies, 42.1 and 18.4 per cent were positive for measles and rubella, respectively. Seroprevalence of Leptospira was 35.5 per cent. The prevalence of hypertension was 13.2 per cent, whereas another 28.9 per cent were pre-hypertensive. The population structure of the Shompen is not skewed and under nutrition was not widely prevalent among the children of <5 yr. The other positive observations were the absence of malaria, filariasis and dengue. However, there was natural infection of measles and rubella. Fungal skin infection and intestinal parasitic infestations were widely prevalent. Although cardiovascular risk profile was low, there were signs of emerging risk of over-weight, hypertension and dyslipidaemia. These together with the high prevalence of smokeless tobacco use may have a serious effect on the cardiovascular disease susceptibility of the Shompen population in the future.

High diagnostic accuracy of quantitative SARS-CoV-2 spike-binding-IgG assay and correlation with in vitro viral neutralizing activity

BackgroundAntibody testing can easily evaluate the clinical status of patients, aid in the diagnosis of multisystem inflammatory syndrome, and monitor the immunity level in the population. However, the applicability of serological tests in detecting antibodies against the severe acute respiratory syndrome 2 (SARS-CoV-2) spike-binding protein remains limited. This study aimed to quantify both serum-derived neutralizing immunoglobulin-G (IgG) antibody activity and the amount of anti-SARS-CoV-2 Spike-IgG (S-IgG) in convalescent sera/plasmas and evaluate the direct correlation between the in vitro IgG-EC50 values and S-IgG values. MethodsWe evaluated the neutralizing activity of purified IgG (IgG-EC50), quantified S-IgG in the serum/plasma of consecutive COVID-19 convalescent individuals using a cell-based virus-neutralizing assay, and determined the correlation between IgG-EC50 and S-IgG. In addition, we evaluated rational cut-off values using the receiver operating characteristic (ROC) curve and calculated the sensitivity and specificity of the quantitative S-IgG assay for moderate and high IgG-EC50. ResultsA high correlation was observed between S-IgG and IgG-EC50 with a Spearman's ρ value of −0.748 (95 % confidence interval [CI]: −0.804–0.678). Using an IgG-EC50 of 50 μg/mL and 20 μg/mL as the cut-off values for moderate and high in vitro neutralizing activity, respectively, the Youden's index values of 287.5 binding antibody units (BAU)/mL and 454.1 BAU/mL determined from the ROC curve showed the highest diagnostic accuracy, with Kappa values of 0.884 (95 % CI: 0.823–0.946) and 0.920 (95 % CI: 0.681–0.979), respectively. ConclusionsQuantitative S-IgG tests are a useful and convenient tool for estimating in vitro virus-neutralizing activity, with a high correlation with IgG-EC50 when the rational cut-off value is carefully determined.

Safety and immunogenicity of PIKA-adjuvanted recombinant SARS-CoV-2 spike protein subunit vaccine as a booster against SARS-CoV-2: a phase II, open-label, randomized, double-blinded study.

This study evaluated the safety and immunogenicity of the PIKA-adjuvanted recombinant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein subunit vaccine as a booster dose for healthy adults who had previously received two or more doses of an inactivated coronavirus disease 2019 (COVID-19) vaccine. The study was a phase II multicenter, double-blinded, comparator-controlled, randomized trial. Participants were randomly assigned to receive either the PIKA COVID-19 vaccine booster dose or an inactivated COVID-19 vaccine (Sinovac, China). Safety was assessed based on adverse events, while immunogenicity was measured by neutralizing antibodies against SARS-CoV-2 and serum immunoglobulin G (IgG) levels. Data on safety and immunogenicity were collected in the short-term (within 14 days after the booster dose) and long-term (from 90 to 365 days after the booster dose). The PIKA-adjuvanted vaccine demonstrated a significant increase in neutralizing antibodies against the Omicron variant (geometric mean ratio [GMR]=2.0 on day 7, p-value <0.001; GMR=2.7 on day 14, p-value <0.001) and the wild type SARS-CoV-2 virus (GMR=2.3 on day 7, p-value <0.001; GMR=2.8 on day 14, p-value<0.001) in the early post-vaccination period when compared to the inactivated vaccine. Additionally, the PIKA COVID-19 vaccine showed higher seroconversion rates for neutralizing antibodies against both variants during the first 14 days post-vaccination. However, there were no significant differences in neutralizing antibody levels between the two vaccines from day 90 to day 360 post-vaccination. Serum IgG antibody levels for the PIKA COVID-19 vaccine were also higher throughout the study period. The incidence of adverse events was slightly higher in the PIKA COVID-19 group, with the most common events being pain at the injection site and headache. All adverse events were mild or moderate, with no reports of severe or life-threatening adverse events in either group. The PIKA COVID-19 vaccine, when administered as a booster dose, showed promising short- and long-term immunogenicity with no emergent safety issues identified. The booster dose of the PIKA COVID-19 vaccine elicited a robust immune response against various SARS-CoV-2 variants and provided some seroprotection for up to 360 days (ClinicalTrials.gov registration number: NCT05463419).

A Prospective Analysis of Sustained Immunity Following Covishield Vaccination

Introduction: The outbreak of Coronavirus Disease 2019 (COVID-19) affected a large number of people worldwide within a short period of time. The mortality rate was high, and there was no specific medicine available to cure it. Therefore, the situation demanded the rapid development of a vaccine. When the vaccines were introduced, there was limited knowledge about their efficacy, side-effects, and duration of protection. Hence, a detailed study was conducted in these areas. Aim: To study the immunological responses following Covishield vaccination and determine the duration of protection offered by the vaccine. Materials and Methods: The present study is a prospective observational study conducted at Sree Balaji Medical College and Hospital, Chennai, Tamil Nadu, India from March 2021 to May 2023, involving the staff members of the hospital and college who were above 18-year-old. Individuals with immunodeficiency, those on immunosuppressive medication, or anyone with proof of COVID-19 were excluded. The total sample size was 56. Blood samples were collected before administering the vaccine, at 0, 3, and 12 months, and tested for Complete Blood Count (CBC), COVID-19-specific Immunoglobulin G (IgG), Cluster of Differentiation (CD) 45, CD3, CD4, CD8, etc. The findings were statistically analysed using Statistical Packages of Social Sciences (SPSS) software version 22.0 and STATA software version 10. Results: A total of 154 volunteers initially provided the first blood samples. However, only 129 of them provided blood samples 2nd time and received two doses of the vaccine. Out of these, only 56 participants completed the fourth time blood test. The results consistently demonstrated a rise in IgG levels over time, with consistently higher levels observed in females. Participants above 45 years exhibited higher IgG levels. Individuals with co-morbidities also showed an increase in IgG levels. The research revealed that individuals who were initially IgG negative experienced a greater fold increase in IgG levels after the first dose of vaccination. The incidence and duration of side-effects post-vaccination reduced with each successive vaccine dose. Conclusion: All the volunteers developed adequate IgG antibodies. Two doses of Covishield effectively resulted in lasting immunity in 94.64% of cases, and three doses achieved 100% immunity. Females and participants above 45 years consistently exhibited higher antibody levels. Individuals with co-morbidities also developed antibodies, albeit at slightly lower levels. The side-effects were mild and short-lived. No long-term after effects were detected even after two years and two months following vaccination.

Elevated Interleukin-6 (IL-6) Levels with Ig (G &amp; M) Antibodies in the Recovery Phase of Patients with COVID-19: Indication of Cytokine Storm and Re-infection

The innate immune response to coronavirus disease (COVID-19) by inflammatory cytokines, such as interleukin 6 (IL-6), has been described as an early response, followed by an adaptive immune response with the production of antibodies. IL-6 is produced in response to viral infections and is crucial for the activation of T cells and the differentiation of B cells, which produce antibodies. Immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies are produced during the initial acute period of infection and the recovery period from the period of onset of symptoms. There has been some relationship between the innate response of the cytokine and the adaptive response of the antibodies in patients with COVID-19 infection. There has been a positive correlation between IL-6 levels and the presence of COVID-19 antibodies, suggesting that higher IL-6 levels may be associated with a stronger immune response and studies have confirmed that patients with higher IL-6 levels have a higher antibody response. High IL-6 levels on admission observed within 2 weeks after onset of symptoms were positively correlated with high concentrations of IgG seen 5 weeks after onset of symptoms. We have previously described elevated IL-6 levels in the sera of 68% of COVID-19 convalescent patients (40–93 days) post-onset of symptoms (recovery phase). In this study we decided to investigate whether there was some relationship between the IL-6 levels in patients 40–93 days post-onset of symptom in the recovery phase and their antibody response using a wide range of antibody assays (iCHROMA IgG, GOLD IgG &amp; IgM, Abbott SARS-CoV-2 IgG II Quant-test (Abbott S IgG), Diasorin Liaison SARS-CoV-2 S1/2 (Diasorin S1/2 IgG). The patients were divided into two groups, those with normal IL-6 levels (&lt;7 pg/ml) and those with elevated IL-6 levels (&gt;7 pg/ml). All patients (100%) had positive IgG antibodies, only 8 out the 28 patients (29%) were positive for IgM antibodies. The mean antibodies concentrations of the patients (n = 9) with normal IL-6 levels (&lt;7 pg/ml) for iCHROMA IgG (20.0 Units), GOLD IgG (34.4 AU/mL), Abbott IgG (4175 AU/mL), Diasorin Liaison IgG (75.8 AU/mL) and GOLD IgM (4.7 AU/mL), respectively. The mean antibodies concentrations of the patients (n = 19) with elevated IL-6 levels (&gt;7 pg/ml) for iCHROMA IgG (20.9 Units), GOLD IgG, (34.9 AU/mL), Abbott IgG (2287 AU/mL), Diasorin Liaison IgG (121.7 AU/mL) and GOLD IgM (11.2 AU/mL), respectively. The antibodies of the patients with the elevated IL-6 levels were significantly higher for Diasorin Liaison IgG (p = 0.02) and GOLD IgM (p = 0.003) but lower for Abbott IgG (p = 0.02). In conclusion, this study using a panel of antibody assays highlights that increased levels of IL-6 in the convalescent phase (recovery phase) indicate an active immune response leading to higher concentrations of antibodies especially IgM, suggesting that cytokine storms and re-infection occur in the recovery phase.

Single ChAdOx1 nCoV-19 dose elicits stronger immune response in previously infected individuals than in SARS-CoV2 naive persons.

Current vaccines against COVID-19 effectively reduce morbidity and mortality and are vitally important for controlling the pandemic. Between December 2020 and February 2021, adenoviral vector vaccines such as ChAdOx1 (AstraZeneca-Oxford) were put in use. Recent reports demonstrate robust serological responses to a single dose of messenger RNA vaccines in individuals previously infected with SARS-CoV-2. We aimed to study the association between previous COVID-19 infection and antibody levels after a single dose of ChAdOx1 nCoV-19. This cross-sectional study was conducted on 657 individuals who were either convalescent or SARS-CoV-2 naive and had received one dose of ChAdOx1 (AstraZeneca). A questionnaire was used to collect data on age, sex, and self-reported history of COVID-19 infection. We then compared the average levels of immunoglobulin G (IgG) between the previously infected and COVID-19-naive participants. We compared the antibody responses of individuals with confirmed prior COVID-19 infection with those of individuals without prior evidence of infection. The mean antibody levels in those who reported no history of COVID-19 infection were substantially lower than in those who were previously infected, in both males and females. Sex-related differences were observed when we compared antibody levels between men and women. In males, anti-S IgG antibody levels were higher in those who had been previously infected (156.1 vs. 87.69 AU/mL, p = .009), compared with the same pattern was observed in females (113.5 vs. 90.69 AU/mL, p = .005). Previous COVID-19 infection is associated with higher levels of SARS-CoV-2 antibodies following ChAdOx1 (AstraZeneca) vaccination. Our finding supports the notion that a single dose of ChAdOx1 nCoV-19 administered post-SARS-CoV-2 infection serves as an effective immune booster. This provides a possible rationale for a single-dose vaccine regimen for previously infected individuals.

Protective antibody concentrations in primary immunodeficiency following infusion with 5% or 10% intravenous immunoglobulin.

Inadequate production of immunoglobulin G (IgG) antibodies renders patients with primary immunodeficiencysusceptible to infection by numerous pathogens, some of which can lead to severe asthma exacerbation and possible death. These patients who are immunocompromised are often reliant on intravenous immunoglobulin (IVIG) therapies, which provide passive antibodies against various respiratory pathogens, including measles virus and encapsulated bacteria. We conducted a subanalysis of data from a multicenter, multinational, phase III, open-label bioequivalencestudy to compare protective concentrations of IgG antibodies provided by a 5% and a 10% IVIG product in patients with primaryimmunodeficiency. Patients on stable 21- or 28-day regimens of previous IVIG products were assigned to receive study treatment (adults: 5% IVIG and 10% IVIG; children: 10% IVIG) at doses of 300-800 mg/kg per infusion. Trough concentrations of total IgG, IgG subclasses, measles-neutralizing antibodies, and IgG against Haemophilus influenzae type b and Streptococcus pneumoniae serotypes were evaluated. A total of 48 patients (33 adults ages 16-55 years; 15 children ages 2-15 years) were enrolled and received treatment.No statistically significant differences in trough concentrations of total IgG, IgG subclasses, measles neutralizing antibodies, or IgG directed at encapsulated bacteria were observed between the 5% and 10% formulations in analyses by age (adult or pediatric) or infusion schedule (every 21 or 28 days). All evaluated patients had trough IgG concentrations above accepted thresholds for protection against disease. These findings support the conclusion that, at dose levels and infusion schedules prescribed in clinical practice,this 5% and 10% IVIG product provided consistent, predictable, and bioequivalent IgG concentrations for adult and pediatricpatients with primary immunodeficiency disease. Both formulations delivered trough antibody concentrations of total IgG, measles- neutralizing antibodies, and antibodies against encapsulated bacteria that are above thresholds accepted as protective.

Immunoglobulin G (IgG) specific responses to recombinant Qβ displayed MSP3 and UB05 in plasma of asymptomatic Plasmodium falciparum-infected children living in two different agro-ecological settings of Cameroon.

in areas with intense perennial malaria transmission, limited data is available on the impact of environmental conditions especially rainfall on naturally acquired immunity against promising malaria vaccine candidates. For this reason, we have compared IgG antibody responses specific to Plasmodium spp. derived MSP3 and UB05 vaccine candidates, in plasma of children living in two areas of Cameroon differing in rainfall conditions. data about children less than 5 years old was collected during the years 2017 and 2018. Next malaria asymptomatic P. falciparum (Pf) infected children were selected following malaria test confirmation. MSP3 and UB05 specific IgG antibody responses were measured in participant´s plasma using enzyme-linked immunosorbent assay (ELISA). interestingly, IgG antibody responses specific to UB05 were significantly higher (p<0.0001) in Pf-negative children when compared to their asymptomatic Pf-infected counterparts living in monomodal rainfall areas. In contrast, a significantly higher (p<0.0001) IgG response to MSP3 was observed instead in asymptomatic Pf-infected children in the same population. In addition, IgG responses specific to UB05 remained significantly higher in bimodal when compared to monomodal rainfall areas irrespective of children´s Pf infection status (p<0.0055 for Pf-positive and p<0.0001 for negative children). On the contrary, IgG antibody responses specific to MSP3 were significantly higher in bimodal relative to monomodal rainfall areas (P<0.0001) just for Pf-negative children. thus IgG antibody responses specific to UBO5 are a better correlate of naturally acquired immunity against malaria in Pf-negative Cameroonian children especially in monomodal rainfall areas.