Total IgG Research Articles

Elucidating allergic reaction mechanisms in response to SARS-CoV-2 mRNA vaccination in adults.

During the COVID-19 pandemic, novel nanoparticle-based mRNA vaccines were developed. A small number of individuals developed allergic reactions to these vaccines although the mechanisms remain undefined. To understand COVID-19 vaccine-mediated allergic reactions, we enrolled 19 participants who developed allergic events within 2 h of vaccination and 13 controls, nonreactors. Using standard hemolysis assays, we demonstrated that sera from allergic participants induced stronger complement activation compared to nonallergic subjects following exvivo vaccine exposure. Vaccine-mediated complement activation correlated with anti-polyethelyne glycol (PEG) IgG (but not IgM) levels while anti-PEG IgE was undetectable in all subjects. Depletion of total IgG suppressed complement activation in select individuals. To investigate the effects of vaccine excipients on basophil function, we employed a validated indirect basophil activation test that stratified the allergic populations into high and low responders. Complement C3a and C5a receptor blockade in this system suppressed basophil response, providing strong evidence for complement involvement in vaccine-mediated basophil activation. Single-cell multiome analysis revealed differential expression of genes encoding the cytokine response and Toll-like receptor (TLR) pathways within the monocyte compartment. Differential chromatin accessibility for IL-13 and IL-1B genes was found in allergic and nonallergic participants, suggesting that invivo, epigenetic modulation of mononuclear phagocyte immunophenotypes determines their subsequent functional responsiveness, contributing to the overall physiologic manifestation of vaccine reactions. These findings provide insights into the mechanisms underlying allergic reactions to COVID-19 mRNA vaccines, which may be used for future vaccine strategies in individuals with prior history of allergies or reactions and reduce vaccine hesitancy.

Markers of allergy and immunoregulation in children under conditions of aerogenic exposure to aluminum

Introduction. The study of sensitization under conditions of aerogenic exposure to aluminum is relevant for preventing the formation of the risk of disorders of the immunological health in the child population. Materials and methods. Preschool three hundred fifty three children living in Eastern Siberia were examined. Observation group included 199 children living in the zone exposed to emissions from non-ferrous metallurgy enterprises, comparison group – 154 children living in a “conditionally clean” area. In the observation area, the average daily dose of aerogenic exposure to aluminum was 0.292 ∙ 10–3 mg/(kg ∙ day), in the comparison area – 0.0376 ∙ 10–3mg/(kg ∙ day). The work used sanitary-hygienic, chemical-analytical, enzyme-linked immunosorbent and allergosorbent research methods. Results. In children living under conditions of aluminum exposure, a twofold excess of aluminum content was identified in biological environments relative to the comparison group (p = 0.001), hyperproduction of IgG to aluminum, CD19+ and CD3+CD8+ lymphocytes (1.6 times), and NKT lymphocytes (2 times) and CD11a+ lymphocytes 1.4 times (p=0.001) was noted, which reflects an imbalance of immunoregulation and the formation of autoallergy. A significant relationship was established between hyperproduction of total IgE and IgG to aluminum (OR=2.29–5.98; 95% CI 1.76–9.52), (RR=1.93–2.66; 95% CI: 1.41–3.54) Limitations of the study. Limited sample size. Conclusion. As markers of allergy and imbalance of immunoregulation in children under conditions of aerogenic exposure to aluminum and with its increased content in biological media, it is necessary to recommend IgG to aluminum as a marker of sensitivity, as well as CD11a+, reflecting the likelihood of developing a risk of developing immunological disadaptation and autosensitization (OR = 2.29–5.98), (RR=1.93–2.66).

Core fucosylation within the Fc-FcγR degradation pathway promotes enhanced IgG levels via exogenous L-fucose

α1,6-Fucosyltransferase (Fut8) is the enzyme responsible for catalyzing core fucosylation. Exogenous L-fucose upregulates fucosylation levels through the GDP-fucose salvage pathway. This study investigated the relationship between core fucosylation and IgG amounts in serum utilizing wild-type (Fut8+/+), Fut8 heterozygous knockout (Fut8+/−), and Fut8 knockout (Fut8−/−) mice. The IgG levels in serum were lower in Fut8+/− and Fut8−/− mice compared with Fut8+/+ mice. Exogenous L-fucose increased IgG levels in Fut8+/− mice, while the ratios of core fucosylated IgG versus total IgG showed no significant difference among Fut8+/+, Fut8+/−, and Fut8+/− mice treated with L-fucose. These ratios were determined by Western blot, lectin blot, and mass spectrometry analysis. Real-time PCR results demonstrated that mRNA levels of IgG Fc and neonatal Fc receptor, responsible for protecting IgG turnover, were similar among Fut8+/+, Fut8+/−, and Fut8+/− mice treated with L-fucose. In contrast, the expression levels of Fc-gamma receptor Ⅳ (FcγRⅣ), mainly expressed on macrophages and neutrophils, were increased in Fut8+/− mice compared to Fut8+/+ mice. The effect was reversed by administrating L-fucose, suggesting that core fucosylation primarily regulates the IgG levels through the Fc-FcγRⅣ degradation pathway. Consistently, IgG internalization and transcytosis were suppressed in FcγRⅣ-knockout cells while enhanced in Fut8-knockout cells. Furthermore, we assessed the expression levels of specific antibodies against ovalbumin and found they were downregulated in Fut8+/− mice, with potential recovery observed with L-fucose administration. These findings confirm that core fucosylation plays a vital role in regulating IgG levels in serum, which may provide insights into a novel mechanism in adaptive immune regulation.

Serum IgG Immunoglobulin Levels are Associated with Reduced PCR Detection of Mycoplasma bovis in Naturally Infected American Bison (Bison bison).

Mycoplasma bovis (M. bovis) is an important pathogen of American bison (Bison bison), associated with high morbidity and mortality epizootics of respiratory and reproductive disease. Despite the significant negative impact on bison health, little is known about the kinetics of disease and the host immune response to infection. To address these questions, a cohort of bison calves was created and serially sampled 5 times, once every 2-3 mo, over a 12-mo period. At each sampling period nasal swab samples were collected and tested by PCR for the presence of M. bovis. Serum samples were also collected and assessed for M. bovis-specific antibodies using both a commercial and an in-house ELISA. Overall, 19/41 bison (46.3%) had positive PCR tests, and 31/41 (75.6%) were seropositive. Over the course of the study, the frequency of PCR-positive nasal swabs and the ELISA scores decreased, although serum samples remained positive for at least 6 mo following the final positive PCR test. Bison were grouped according to results from the in-house ELISA into high-responder (n=7), low-responder (n=5), and seronegative (n=7) groups. M. bovis-specific IgG antibody levels were significantly elevated in the high-responder group compared to the low-responder and seronegative groups. The differences were statistically significant for 3/5 sampling periods. A trend toward increased IgG2 levels was observed in the high-responder group. High total IgG responses correlated with a decline in positive PCR tests from nasal swabs. These data provide evidence that a strong humoral response is beneficial and is probably involved in the clearance of M. bovis from bison.

Modulation of T-Cell-Dependent Humoral Immune Response to Influenza Vaccine by Multiple Antioxidant/Immunomodulatory Micronutrient Supplementation.

Notwithstanding prevalence gaps in micronutrients supporting immune functions, the significance of their deficits/supplementation for the efficacy of vaccines is underinvestigated. Thus, the influence of supplementation combining vitamins C and D, zinc, selenium, manganese, and N-acetyl cysteine on immune correlates/surrogates of protection conferred by a quadrivalent influenza vaccine (QIV) in mice was investigated. The supplementation starting 5 days before the first of two QIV injections given 28 days apart increased the serum titres of total and neutralizing IgG against each of four influenza strains from QIV. Accordingly, the frequencies of germinal center B cells, follicular CD4+ T helper (Th) cells, and IL-21-producing Th cells increased in secondary lymphoid organs (SLOs). Additionally, the supplementation improved already increased IgG response to the second QIV injection by augmenting not only neutralizing antibody production, but also IgG2a response, which is important for virus clearance, through favoring Th1 differentiation as indicated by Th1 (IFN-γ)/Th2 (IL-4) signature cytokine level ratio upon QIV restimulation in SLO cell cultures. This most likely partly reflected antioxidant action of the supplement as indicated by splenic redox status analyses. Thus, the study provides a solid scientific background for further research aimed at repurposing the use of this safe and inexpensive micronutrient combination to improve response to the influenza vaccine.

Impact of ginger powder (Zingiber officinale) supplementation on the performance, biochemical parameters, antioxidant status, and rumen fermentation in Ossimi rams.

Ginger (Zingiber officinale) has great potential as a growth promoter and immunostimulant in ruminant nutrition. This study assessed the impact of ginger powder supplementation on Ossimi rams' rumen fermentation, biochemical parameters, and antioxidant levels. Fifteen Ossimi rams, aged 10 ± 1.3 months and weighing 30 ± 1.5 kg. Rams were randomly divided into three experimental groups: The control group (G1) received standard feed, while ginger powder (5 g and 7 g/kg body weight [BW] for G2 and G3, respectively) mixed in water was administered to groups G2 and G3 before their standard feed. The control group recorded higher dry matter (DM) intake values (p < 0.05) than the ginger-treated groups. The ginger-treated groups showed superiority (p < 0.05) in weight gain and feed conversion compared to the control group. The digestion coefficients of DM, crude protein, and crude fiber were significantly (p < 0.05) increased by a high dose (7 g/Kg BW) of ginger supplementation, whereas organic matter, ether extract, and nitrogen-free extract digestibility remained unchanged. Compared to the control group, the rams given 5 g of ginger had significantly less (p < 0.05) total protein and globulin in their serum, but the rams given 7 g of ginger had significantly more (p < 0.05) of these proteins. In the ginger groups, these levels were significantly (p < 0.01) lower than those in the control group for serum creatinine, uric acid, urea, total lipids, triglycerides, total cholesterol, glucose, serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase. Rams given ginger had significant growth hormone, insulin-like growth factor-1, total superoxide dismutase, GSH-Px, TAC, immunoglobulin (Ig) A, and IgG enhancement (p < 0.01), and a decrease (p < 0.01) in malondialdehyde concentration compared to the control group. Significant increases in total short-chain volatile fatty acids, acetic, propionic, and isovaleric acids (p < 0.05), and significant decreases in NH3N and protozoa (p < 0.01). Ginger powder (5 g and 7 g) can improve growth, immune responses, antioxidant status, and ruminal parameters in rams. Further study is needed to evaluate the effect of ginger on different types of animals (cow, buffalo, and goat) to develop new feed additives.

Hospitalisations and humoral COVID-19 vaccine response in vaccinated rituximab-treated multiple sclerosis patients

BackgroundPatients with multiple sclerosis (MS) treated with anti-CD20 therapies such as rituximab may have increased risk of severe COVID-19 disease. Vaccination induces protective immunity, but humoral vaccine response is known to be attenuated in rituximab-treated MS-patients-patients, which has indicated a need for real world data on severe morbidity and mortality from COVID-19 after vaccination. MethodsRituximab-treated patients treated at Haukeland University Hospital were identified through the National MS Registry and invited to participate in the study by giving a consent and providing a blood sample 3 weeks or later after ordinary COVID-19- vaccination, i.e. 2 doses given with a standard interval of 3 weeks. Blood samples were analysed with Enzyme-Linked Immunosorbent assay (ELISA) to evaluate humoral vaccine response with screening test against receptor-binding domain (RBD) and confirmatory Spike IgG-specific ELISA. A haemagglutination test (HAT) was performed as a marker of neutralizing antibodies. Patient serum concentration of rituximab were quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS). Registry data from the Norwegian MS registry and information on hospitalization from patient records were collected and linked to laboratory results. Results111 patients were included in the study. A total of 7 (6.3%) were hospitalized due to COVID-19 disease during the observation period. No patient was admitted to ICU and there were no deaths. 34.2% did not have detectable titre of SARS CoV-2 Spike IgG antibodies, 72.1% did not have a detectable titre of SARS CoV-2 RBD antibodies, and 88.2% did not have a detectable HAT titre. There was a correlation between hospitalisation and the absence of SARS CoV-2 Spike IgG antibody titre, and between hospitalisation and MS disease duration, as well as between spike IgG antibody titre and CD19 B-cell count, time since last rituximab infusion, cumulative rituximab treatment time and total IgG level in the patients. ConclusionA substantial proportion of rituximab-treated MS-patients-patients did not have detectable humoral vaccine responses after 2 doses of COVID-19 vaccination. Despite this, the cumulative percentage of patients hospitalized with COVID-19 disease throughout the observation period of 22 months was low, and no patients required ICU treatment. The results support that vaccinated MS-patients treated with rituximab have a protective effect against serious Covid-19 infection.

In silico and in vivo Investigations of the Immunoreactivity of Klebsiella pneumoniae OmpA Protein as a Vaccine Candidate

The growing threat of antibiotic resistance and Klebsiella pneumoniae infection in healthcare settings highlights the urgent need for innovative solutions, such as vaccines, to address these challenges. This study sought to assess the potential of using K. pneumoniae outer membrane protein A (OmpA) as a vaccine candidate through both in silico and in vivo analyses. The study examined the OmpA protein sequence for subcellular localization, antigenicity, allergenicity, similarity to the human proteome, physicochemical properties, B-cell epitopes, MHC binding sites, tertiary structure predictions, molecular docking, and immune response simulations. The ompA gene was cloned into the pET-28a (+) vector, expressed, purified and confirmed using Western blotting analysis. IgG levels in the serum of the immunized mice were measured using ELISA with dilutions ranging from 1:100 to 1:6400, targeting recombinant outer membrane protein A (rOmpA) and K. pneumoniae ATCC 13883. The sensitivity and specificity of the ELISA method were also assessed. The bioinformatics analysis identified rOmpA as a promising vaccine candidate. The immunized group demonstrated significant production of specific total IgG antibodies against rOmpA and K. pneumoniae ATCC1 13883, as compared to the control group (p < 0.0001). The titers of antibodies produced in response to bacterial exposure did not show any significant difference when compared to the anti-rOmpA antibodies (p > 0.05). The ELISA test sensitivity was 1:3200, and the antibodies in the serum could accurately recognize K. pneumoniae cells. This study is a significant advancement in the development of a potential vaccine against K. pneumoniae that relies on OmpA. Nevertheless, additional experimental analyses are required.

Circulating IgG Fragments for Gastric Cancer and Esophageal Cancer.

Blood serum of patients with gastric (n = 68) and esophageal (n = 43) cancer was assessed for proteolytic fragments of IgG. Serum samples of 20 healthy donors were used as a control. We analyzed indicators of hemostasis (prothrombin time, fibrinogen, plasminogen activity, a2-antiplasmin activity, protein C activity) in blood plasma and the level of total IgG in the blood serum. The median IgG-LysK of healthy donors was lower than in esophageal cancer and in patients with gastric cancer. ROC-analysis showed high sensitivity (91%) and specificity (85%) in the group with esophageal cancer but 68% and 85%, respectively, in patients with gastric cancer. Analysis of false negatives IgG-LysK in cancer patients showed that most patients had an advanced stage of cancer accompanied by metastases. Total IgG in the plasma of patients with false-negative IgG-LysK values was 30% lower than in samples with positive values, while the level of a2-antiplasmin was increased and the prothrombin time was shorter. These changes in blood homeostasis may be the reason for an increase in the proportion of false-negative values of the IgG-LysK coefficient. Circulatory IgG-LysK levels increase in the early stages of such cancers as gastric and esophageal cancers. Thus, when used in a panel with other more specific markers for these pathologies, this indicator can significantly increase the early detection of cancer.

Immunoadsorption and Plasma Exchange are Comparable in Anti-Neutrophil Cytoplasmic Antibodies or Anti-Glomerular Basement Membrane Removal Kinetics

IntroductionApheresis allows the fast removal of auto-antibodies in anti-glomerular basement membrane (GBM) disease, and in severe ANCA-associated vasculitis. The CINEVAS study tested whether immunoadsorption (IA) allowed a faster removal of ANCA and/or anti-GBM antibodies than plasma exchanges (PEx). MethodsCINEVAS was a prospective multicenter study comparing IA to PEx in consecutive patients with ANCA and/or anti-GBM vasculitides. The primary objective was the reduction rate in auto-antibody titers between the beginning of the first and the end of the seventh apheresis session. Secondary objectives were: number of sessions needed to obtain desired reduction rates; reduction rates of total immunoglobulin (Ig) levels; tolerance of sessions; and patients’ outcome. ResultsThe results of 38 patients (16 treated with IA and 22 with PEx), and 43 auto-antibodies, were analyzed. There was no difference in the reduction rates in auto-antibody titers over 7 sessions between IA and PEx (respectively 98% vs 96%, p=0.39). The numbers of sessions needed to obtain undetectable auto-antibodies, or 50%, 75% or 90% reductions, did not differ between techniques. Greater reduction rates of auto-antibodies were observed when plasma was separated by filtration compared to centrifugation, with IA and PEx. IA allowed a greater reduction in total IgG levels, and better preservation of total IgA and IgM levels than PEx. PEx sessions required higher volumes of plasma, IA sessions higher volumes of citrate; IA sessions were longer. ConclusionsImmunoadsorption and plasma exchange were comparable in ANCA or anti-GBM removal kinetics, despite a faster reduction in total IgG with IA.

Stability, enrichment, and quantification of total and HPV16-specific IgG present in first-void urine

First-void urine (FVU) samples, containing human papillomavirus (HPV)-specific IgG from female genital tract secretions, provide a non-invasive option for disease monitoring and vaccine impact assessment. This study explores the utility of FVU for IgG quantification, exploring stability and compatibility with DNA preservation methods, alongside various IgG enrichment methods. Healthy female volunteers provided FVU and serum samples. FVU was collected with or without urine conservation medium (UCM) and stored under different conditions before freezing at −80 °C. Four IgG enrichment methods were tested on FVU samples. All samples were analyzed using three total human IgG quantification assays and an in-house HPV16-specific IgG assay. Samples stored with UCM buffer had higher total and HPV16-specific IgG concentrations (p ≤ 0.01) and IgG remained stable for at least 14 days at room temperature. Among IgG enrichment methods, Amicon filtration (AM) and AM combined with Melon Gel purification (AM-MG) provided similar HPV16-IgG concentrations, correlating strongly with serum levels. Protein G magnetic beads methods were incompatible with time-resolved fluorescence-based assays. This study highlights FVU as a reliable and convenient sample for IgG quantification, demonstrating stability for at least 14 days at room temperature and compatibility with UCM DNA preservation. It emphasizes the need to select appropriate IgG enrichment methods and confirms the suitability of both AM and AM-MG methods, with a slightly better performance for AM-MG.

Designing the fusion protein of rotavirus VP8 and hepatitis A virus VP1 and evaluating the immunological response in BALB/c mice.

Rotavirus and Hepatitis A virus are responsible for causing gastroenteritis and jaundice. The current vaccination approaches have proven insufficient, especially in low-income countries. In this study, we presented a novel dual-vaccine candidate that combines the rotavirus VP8 protein and the hepatitis A virus VP1. The VP8*-rotavirus+AAY+HAV-VP1 fusion protein was produced using an Escherichia coli expression system. The recombinant protein had a molecular weight of approximately 45.5 kDa and was purified through affinity chromatography. BALB/c mice were injected subcutaneously with the recombinant protein, VP1, VP8 and vaccines for rotavirus and hepatitis A virus, both with and without ALUM and M720 adjuvants. ELISA assays were used to measure total IgG, IgG1, IgG2, and short-term and long-term IL-5 and IFN-γ responses. The fusion protein, when combined with adjuvants, elicited significantly higher total IgG, IgG1, and IgG2 responses compared to VP1 and VP8 alone, as well as the rotavirus and hepatitis A vaccines. Furthermore, it induced a higher short-term IL-5 and IFN-γ response while demonstrating a higher long-term IL-5 response compared to the rotavirus and hepatitis A vaccines. This study demonstrates that the VP8*-rotavirus+AAY+HAV-VP1 fusion protein is a promising dual vaccine candidate for immunization against hepatitis A and rotaviruses.

Aspergillus fumigatus binding IgA and IgG1 are increased in bronchoalveolar lavage fluid of horses with neutrophilic asthma.

Equine asthma (EA) is a common lower airway disease in horses, but whether its pathogenesis is allergic is ambiguous. Extrinsic stimuli like hay dust induce acute exacerbation of clinical signs and sustained local neutrophilic inflammation in susceptible horses. Aspergillus fumigatus is an EA stimulus, but it is unclear if it merely acts as an IgE-provoking allergen. We aimed to comprehensively analyze immunoglobulin (Ig) isotypes in EA, elucidating their binding to different A. fumigatus antigens, and their quantities systemically in serum and locally in bronchoalveolar lavage fluid (BALF). Serum and BALF from healthy horses (HE, n = 18) and horses with mild-moderate asthma (MEA, n = 20) or severe asthma (SEA, n = 24) were compared. Ig isotype (IgG1, IgG3/5, IgG4/7, IgG6, IgA, and IgE) binding to nine antigens (A.fumigatus lysate, and recombinant Asp f 1, Asp f 7, Asp f 8, dipeptidyl-peptidase 5, class II aldolase/adducin domain protein, glucoamylase, beta-hexosaminidase, and peptide hydrolase) was compared by enzyme-linked immunosorbent assays. Total Ig isotype contents were determined by bead-based assays. MEA and SEA differed from HE but hardly from each other. Compared to HE, asthmatic horses showed increased anti-A. fumigatus binding of IgG (BALF and serum) and IgA (BALF). Serum and BALF IgE binding and total IgE contents were similar between HE and EA. Single antigens, as well as A. fumigatus lysate, yielded similar Ig binding patterns. Serum and BALF IgG1 binding to all antigens was increased in SEA and to several antigens in MEA. Serum IgG4/7 binding to two antigens was increased in SEA. BALF IgA binding to all antigens was increased in SEA and MEA. Total BALF IgG1 and IgG4/7 contents were increased in SEA, and serum IgG4/7 content was increased in MEA compared to HE. Yet, total isotype contents differentiated EA and HE less clearly than antigen-binding Ig. A. fumigatus immunogenicity was confirmed without identification of single dominant antigens here. A. fumigatus provoked elevated BALF IgG1 and IgA binding, and these isotypes appear relevant for neutrophilic EA, which does not support allergy. BALF Ig isotype differentiation beyond IgE is crucial for a comprehensive analysis of immune responses to fungi in EA pathogenesis.

Blood-stage malaria vaccine candidate RH5.1/Matrix-M in healthy Tanzanian adults and children; an open-label, non-randomised, first-in-human, single-centre, phase 1b trial

A blood-stage Plasmodium falciparum malaria vaccine would provide a second line of defence to complement partially effective or waning immunity conferred by the approved pre-erythrocytic vaccines. RH5.1 is a soluble protein vaccine candidate for blood-stage P falciparum, formulated with Matrix-M adjuvant to assess safety and immunogenicity in a malaria-endemic adult and paediatric population for the first time. We did a non-randomised, phase 1b, single-centre, dose-escalation, age de-escalation, first-in-human trial of RH5.1/Matrix-M in Bagamoyo, Tanzania. We recruited healthy adults (aged 18-45 years) and children (aged 5-17 months) to receive the RH5.1/Matrix-M vaccine candidate in the following three-dose regimens: 10 μg RH5.1 at 0, 1, and 2 months (Adults 10M), and the higher dose of 50 μg RH5.1 at 0 and 1 month and 10 μg RH5.1 at 6 months (delayed-fractional third dose regimen; Adults DFx). Children received either 10 μg RH5.1 at 0, 1, and 2 months (Children 10M) or 10 μg RH5.1 at 0, 1, and 6 months (delayed third dose regimen; Children 10D), and were recruited in parallel, followed by children who received the dose-escalation regimen (Children DFx) and children with higher malaria pre-exposure who also received the dose-escalation regimen (High Children DFx). All RH5.1 doses were formulated with 50 μg Matrix-M adjuvant. Primary outcomes for vaccine safety were solicited and unsolicited adverse events after each vaccination, along with any serious adverse events during the study period. The secondary outcome measures for immunogenicity were the concentration and avidity of anti-RH5.1 serum IgG antibodies and their percentage growth inhibition activity (GIA) in vitro, as well as cellular immunogenicity to RH5.1. All participants receiving at least one dose of vaccine were included in the primary analyses. This trial is registered at ClinicalTrials.gov, NCT04318002, and is now complete. Between Jan 25, 2021, and April 15, 2021, we recruited 12 adults (six [50%] in the Adults 10M group and six [50%] in the Adults DFx group) and 48 children (12 each in the Children 10M, Children 10D, Children DFx, and High Children DFx groups). 57 (95%) of 60 participants completed the vaccination series and 55 (92%) completed 22 months of follow-up following the third vaccination. Vaccinations were well-tolerated across both age groups. There were five serious adverse events involving four child participants during the trial, none of which were deemed related to vaccination. RH5-specific T cell and serum IgG antibody responses were induced by vaccination and purified total IgG showed in vitro GIA against P falciparum. We found similar functional quality (ie, GIA per μg RH5-specific IgG) across all age groups and dosing regimens at 14 days after the final vaccination; the concentration of RH5.1-specific polyclonal IgG required to give 50% GIA was 14·3 μg/mL (95% CI 13·4-15·2). 11 children were vaccinated with the delayed third dose regimen and showed the highest median anti-RH5 serum IgG concentration 14 days following the third vaccination (723 μg/mL [IQR 511-1000]), resulting in all 11 who received the full series showing greater than 60% GIA following dilution of total IgG to 2·5 mg/mL (median 88% [IQR 81-94]). The RH5.1/Matrix-M vaccine candidate shows an acceptable safety and reactogenicity profile in both adults and 5-17-month-old children residing in a malaria-endemic area, with all children in the delayed third dose regimen reaching a level of GIA previously associated with protective outcome against blood-stage P falciparum challenge in non-human primates. These data support onward efficacy assessment of this vaccine candidate against clinical malaria in young African children. The European and Developing Countries Clinical Trials Partnership; the UK Medical Research Council; the UK Department for International Development; the National Institute for Health and Care Research Oxford Biomedical Research Centre; the Division of Intramural Research, National Institute of Allergy and Infectious Diseases; the US Agency for International Development; and the Wellcome Trust.

Long-Term Dynamics of Serum α-MSH and α-MSH-Binding Immunoglobulins with a Link to Gut Microbiota Composition in Patients with Anorexia Nervosa

Introduction: Immunoglobulins (Ig) reactive with α-melanocyte-stimulating hormone (α-MSH), an anorexigenic neuropeptide, are present in humans and were previously associated with eating disorders. In this longitudinal study involving patients with anorexia nervosa (AN), we determined whether α-MSH in serum is bound to IgG and analyzed long-term dynamics of both α-MSH peptide and α-MSH-reactive Ig in relation to changes in BMI and gut microbiota composition. Methods: The study included 64 adolescents with a restrictive form of AN, whose serum samples were collected at hospital admission, discharge, and during a 1-year follow-up visit and 41 healthy controls, all females. Results: We found that in both study groups, approximately 40% of serum α-MSH was reversibly bound to IgG and that levels of α-MSH-reactive IgG but not of α-MSH peptide in patients with AN were low at hospital admission but recovered 1 year later. Total IgG levels were also low at admission. Moreover, BMI-standard deviation score correlated positively with α-MSH IgG in both groups studied but negatively with α-MSH peptide only in controls. Significant correlations between the abundance of specific bacterial taxa in the gut microbiota and α-MSH peptide and IgG levels were found in both study groups, but they were more frequent in controls. Conclusion: We conclude that IgG in the blood plays a role as an α-MSH-binding protein, whose characteristics are associated with BMI in both patients with AN and controls. Furthermore, the study suggests that low production of α-MSH-reactive IgG during the starvation phase in patients with AN may be related to altered gut microbiota composition.

Thyroglobulin specific IgE and a possible link to suspected penicillin induced allergic skin manifestations – cross sectional study

Porcine thyroglobulin was important in the discovery of alpha-Gal allergy. Here, the linkage of porcine thyroglobulin-specific IgE with IgE positivity to routinely assessed allergens and to the incoming diagnosis within a population of suspected atopic individuals is explored.IgE, IgA, total IgG and IgG subclasses to porcine thyroglobulin, IgE to bovine, human thyroglobulin and meat extract were measured with ELISA. The following correlations were observed in IgE binding to porcine and bovine thyroglobulin (r = 0.910, p = 1x10−17), porcine and human thyroglobulin (r = 0.635, p = 4x10−6), human and bovine thyroglobulin (r = 0.746, p = 6x10−9) and porcine thyroglobulin and meat extract (r = 0.482, p = 0.0009). Only one out of ten samples which showed binding to porcine thyroglobulin in ELISA tested positive with ImmunoCAP alpha-Gal, implying different epitope/s. Increased IgE binding was detected towards a more electronegative fraction of porcine thyroglobulin separated according to charge and the binding could be partially inhibited by galactose.Anti-thyroglobulin IgE was found in 29.7% of the population, in subjects who were significantly younger, p < 0.0001 and it occurred more frequently in patients referred for testing penicillin specific IgE (OR 2.48, p = 0.0059) and were negative. IgE specific to porcine, bovine and possibly human thyroglobulin may be implicated in post-infectious skin manifestation misinterpreted as penicillin allergy.

Serological Responses of Guinea Pigs and Heifers to Eight Different BoAHV-1 Vaccine Formulations.

Bovine alphaherpesvirus 1 (BoAHV-1) infection affects the production and reproductive performance of dairy and beef livestock, resulting in considerable economic losses. In addition to biosecurity measures, vaccination programs are effective strategies for controlling and preventing BoAHV-1 infection and transmission. We evaluated the serological immune response against BoAHV-1 induced by eight different formulations of commercial vaccines: three modified live vaccines and five killed vaccines containing BoAHV type 1 or types 1 and 5. In the first experiment, 50 BoAHV-1-seronegative guinea pigs were assigned to eight groups; each individual in the treatment groups received two doses (one-fifth of the bovine dose). The second experiment was conducted using 29 crossbred Holstein × Gir heifers in four groups of six to nine animals each. The serological immune response against BoAHV-1 was measured using virus neutralization and enzyme-linked immunosorbent assays to measure the total IgG against BoAHV. We evaluated the effects of the vaccine, time, and interaction of the vaccine and time on neutralizing antibodies against BoAHV-1. Killed vaccines produced low levels of antibodies against BoAHV-1, whereas modified live vaccines produced high levels of antibodies capable of providing neutralizing titers in the vaccinated animals, with the thermosensitive modified live vaccine showing the highest levels of antibodies.

Development of a human papillomavirus (HPV) multiplex immunoassay to profile HPV antibodies.

Neutralizing antibodies (NAbs) are considered the primary mechanism of vaccine-mediated protection against human papillomaviruses (HPV), the causative agent of cervical cancer. However, the minimum level of NAb needed for protection is currently unknown. The HPV pseudovirion-based neutralization assay (PBNA) is the gold standard method for assessing HPV antibody responses but is time-consuming and labor-intensive. With the development of higher valency HPV vaccines, alternative serological assays with the capacity for multiplexing would improve efficiency and output. Here we describe a multiplex bead-based immunoassay to characterize the antibody responses to the seven oncogenic HPV types (HPV16/18/31/33/45/52/58) contained in the current licensed nonavalent HPV vaccine. This assay can measure antibody isotypes and subclasses (total IgG, IgM, IgA1-2, IgG1-4), and can be adapted to measure other antibody features (e.g., Fc receptors) that contribute to vaccine immunity. When tested with serum samples from unvaccinated and vaccinated individuals, we found high concordance between HPV-specific IgG using this multiplex assay and NAbs measured with PBNA. Overall, this assay is high-throughput, sample-sparing, and time-saving, providing an alternative to existing assays for the measurement and characterization of HPV antibody responses.

Natural antibodies targeting LPS in pleural effusions of various etiologies.

Respiratory infection, cancer, and heart failure can cause abnormal accumulation of fluid in the pleural cavity. The immune responses within the cavity are orchestrated by leucocytes that reside in the serosal-associated lymphoid tissue. Natural antibodies (NAbs) are abundant in the serum (S) having a major role in systemic and mucosal immunity; however, their occurrence in pleural fluid (PF) remains an open question. Our aim herein was to detect and measure the levels of NAbs (IgM, IgG, IgA) targeting lipopolysaccharides (LPS) in both the pleural fluid and the serum of 78 patients with pleural effusions (PEs) of various etiologies. The values of anti-LPS NAb activity were extracted through a normalization step regarding the total IgM, IgG, and IgA levels, all determined by in-house ELISA. In addition, the ratios of PF/S values were analyzed further with other critical biochemical parameters from pleural fluids. Anti-LPS NAbs of all Ig classes were detected in most of the samples, while a significant increase of anti-LPS activity was observed in infectious and noninfectious compared with malignant PEs. Multivariate linear regression confirmed a negative correlation of IgM and IgA anti-LPS PF/S ratio with malignancy. Moreover, anti-LPS NAbs PF/S measurements led to increased positive and negative predictive power in ROC curves generated for the discrimination between benign and malignant PEs. Our results highlight the role of anti-LPS NAbs in the pleural cavity and demonstrate the potential translational impact that should be further explored.NEW & NOTEWORTHY Here we describe the detection and quantification of natural antibodies (NAbs) in the human pleural cavity. We show for the first time that IgM, IgG, and IgA anti-LPS natural antibodies are detected and measured in pleural effusions of infectious, noninfectious, and malignant etiologies and provide clinical correlates to demonstrate the translational impact of our findings.

Superior protection against paratuberculosis by a heterologous prime-boost immunization in a murine model

Vaccination is the best strategy to control Paratuberculosis (PTB), which is a significant disease in cattle and sheep. Previously we showed the humoral and cellular immune response induced by a novel vaccine candidate against PTB based on the Argentinian Mycobacterium avium subspecies paratuberculosis (Map) 6611 strain. To improve 6611 immunogenicity and efficacy, we evaluated this vaccine candidate in mice with two different adjuvants and a heterologous boost with a recombinant modified vaccinia Ankara virus (MVA) expressing the antigen 85A (MVA85A). We observed that boosting with MVA85A did not improve total IgG or specific isotypes in serum induced by one or two doses of 6611 formulated with incomplete Freund’s adjuvant (IFA). However, when 6611 was formulated with ISA201 adjuvant, MVA85A boost enhanced the production of IFNγ, Th1/Th17 cytokines (IL-2, TNF, IL-17A) and IL-6, IL-4 and IL-10. Also, this group showed the highest levels of IgG2b and IgG3 isotypes, both important for better protection against Map infection in the murine model. Finally, the heterologous scheme elicited the highest levels of protection after Map challenge (lowest CFU count and liver lesion score). In conclusion, our results encourage further evaluation of 6611 strain + ISA201 prime and MVA85A boost in bovines.