Higher Antibody Concentrations Research Articles

Biochemical rationale for transfusion of high titre COVID-19 convalescent plasma

We aimed to model binding of donor antibodies to virus that infects COVID-19 patients following transfusion of convalescent plasma (CCP). An immunosorbent assay was developed to determine apparent affinity (Kd, app). Antibody binding to virus was modelled using antibody concentration and estimations of viral load. Assay and model were validated using reference antibodies and clinical data of monoclonal antibody therapy. A single Kd, app or two resolvable Kd, app were found for IgG in 11% or 89% of CCP donations, respectively. For IgA this was 50%-50%. Median IgG Kd, app was 0.8nM and 3.6nM for IgA, ranging from 0.1-14.7nM and 0.2-156.0nM respectively. The median concentration of IgG was 44.0nM (range 8.4-269.0nM) and significantly higher than IgA at 2.0nM (range 0.4-11.4nM). The model suggested that a double CCP transfusion (i.e. 500 mL) allows for > 80% binding of antibody to virus provided Kd, app was < 1nM and concentration > 150nM. In our cohort from the pre-vaccination era, 4% of donations fulfilled these criteria. Low and mid-range viral loads are found early post exposure, suggesting that convalescent plasma will be most effective then. This study provides a biochemical rationale for selecting high affinity and high antibody concentration CCP transfused early in the disease course.

TRLR-02 TARGETING GLIOBLASTOMA MICROENVIRONMENT TO UNLEASH IMMUNE FORCES

Abstract Brain cancer has persistently eluded therapeutic advances over the past three decades. Here, we aim to raise awareness of the potential differences between the cancer microenvironment within the brain vs. peripheral organ cancers, which may contribute to the therapeutic setbacks observed in brain cancer treatment. While the blood-brain barrier has long been implicated in drug impermeability, its impact on brain cancer may extend far beyond mere drug exclusion. Studies have shown that soluble factors such as VEGF are more concentrated in brain cancer than in any other malignancies. Moreover, recent studies revealed that VEGF, TWEAK, and others can also press on the immune brakes. Therefore, we hypothesize that normalizing the tumor microenvironment could pave the way for effective therapeutic interventions, especially immunotherapy. Our in vitro studies confirmed abundant production of VEGF by glioblastoma 1 (GBM1) cell line, which is exceptionally well scavenged by the anti-VEGF antibody – bevacizumab. Moreover, in vitro, co-culture of T cells and GBM1 cell line without vascular component demonstrated no therapeutic activity of bevacizumab or typical immunotherapeutic drug – anti-PD1 checkpoint inhibitor – nivolumab given in monotherapies. However, a combination of both antibodies revealed therapeutic efficacy in a dose-dependent manner in our experimental system. Currently, intravenous delivery of bevacizumab is the standard of care in patients with glioblastoma recurrence, but its effectiveness has not been proven in this group of patients. Intravenous nivolumab failed in clinical trials. Based on our observations and the negligible penetration of antibodies to the brain, we hypothesize that transiently opening the blood-brain barrier may be necessary to enhance antibody delivery to the tumor microenvironment, alleviate immune suppression, and unlock immune cell activity. Therefore, achieving high antibody concentrations in brain cancer tissue, coupled with a combination of classic checkpoint inhibitors with scavengers of soluble immunosuppressive molecules, could herald a new era of brain cancer therapy.

Severe acute respiratory syndrome coronavirus-2 seroprevalence in non-vaccinated people living with HIV in Uganda during 2022

A cross-sectional study on severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) seroprevalence among unvaccinated people living with HIV (PLWH) was conducted in Kampala, Uganda, in 2022. Data collection was done using a structured questionnaire. SARS-CoV-2 serologies were done using the Roche Elecsys Anti-SARS-CoV-2 S immunoassay, which assesses the adaptive humoral immune response to the SARS-CoV-2 Spike protein. A total of 575 PLWH (female n=355, 61.7%) with a median age of 49 years (IQR 39-55) were included. SARS-CoV-2 seroprevalence was 93%. The majority had antibody concentration levels ≥ 250 U/ml (n=383, 66.6%). Participants aged &amp;gt;55 years were significantly more likely to have lower antibody concentrations compared to younger participants (p-value &amp;lt; 0.001). A high BMI (≥ 30 kg/m2) was significantly associated with higher antibody concentrations (p-value 0.001). Concerning COVID-19 history, a small proportion of participants (n=79, 13.6%) reported contact with a known COVID-19 patient. Only 8.1% (n=47) had ever had a nasopharyngeal swab for SARS-CoV-2 RT-PCR done, and 3.1% (n=18) actually had a laboratory-confirmed SARS-CoV-2 infection in the past. SARS-CoV-2 seroprevalence was high among our study population, which may be attributed to the fact that the study took place right after all restrictions were lifted and the population was exposed to the dominant Omicron variant. Interestingly, only a small proportion of infections had been laboratory-confirmed.

Factors Associated With Hepatitis A Seropositivity at 23 Years After Childhood Vaccination.

We evaluated factors associated with the presence of hepatitis A virus antibodies 23 years after initiating vaccination at ages 6-15 months. Among 67 participants, 86% (42/49) of those vaccinated at ages 12-15 months and 61% (11/18) of those vaccinated at 6 months remained seropositive at 23 years. Lack of maternal antibodies at enrollment and higher initial vaccine response were independently associated with higher antibody concentrations at 23 years. Further research is needed to assess the duration of hepatitis A vaccine protection and possible need for a booster dose.

Quantitative proteomics reveals cellular responses to individual mAb expression and tunicamycin in CHO cells

Chinese hamster ovary (CHO) cells are popular in the pharmaceutical industry for their ability to produce high concentrations of antibodies and their resemblance to human cells in terms of protein glycosylation patterns. Current data indicate the relevance of CHO cells in the biopharmaceutical industry, with a high number of product commendations and a significant market share for monoclonal antibodies. To enhance the production capabilities of CHO cells, a deep understanding of their cellular and molecular composition is crucial. Genome sequencing and proteomic analysis have provided valuable insights into the impact of the bioprocessing conditions, productivity, and product quality. In our investigation, we conducted a comparative analysis of proteomic profiles in high and low monoclonal antibody–producing cell lines and studied the impact of tunicamycin (TM)-induced endoplasmic reticulum (ER) stress. We examined the expression levels of different proteins including unfolded protein response (UPR) target genes by using label-free quantification techniques for protein abundance. Our results show the upregulation of proteins associated with protein folding mechanisms in low producer vs. high producer cell line suggesting a form of ER stress related to specific protein production. Further, Hspa9 and Dnaja3 are notable candidates activated by the mitochondria UPR and play important roles in protein folding processes in mitochondria. We identified significant upregulation of Nedd8 and Lgmn proteins in similar levels which may contribute to UPR stress. Interestingly, the downregulation of Hspa5/Bip and Pdia4 in response to tunicamycin treatment suggests a low-level UPR activation.Key points• Proteome profiling of recombinant CHO cells under mild TM treatment.• Identified protein clusters are associated with the unfolded protein response (UPR).• The compared cell lines revealed noticeable disparities in protein expression levels.

MRNA Vaccine for Alzheimer's Disease: Pilot Study.

The escalating global healthcare challenge posed by Alzheimer's Disease (AD) and compounded by the lack of effective treatments emphasizes the urgent need for innovative approaches to combat this devastating disease. Currently, passive and active immunotherapies remain the most promising strategy for AD. FDA-approved lecanemab significantly reduces Aβ aggregates from the brains of early AD patients administered biweekly with this humanized monoclonal antibody. Although the clinical benefits noted in these trials have been modest, researchers have emphasized the importance of preventive immunotherapy. Importantly, data from immunotherapy studies have shown that antibody concentrations in the periphery of vaccinated people should be sufficient for targeting Aβ in the CNS. To generate relatively high concentrations of antibodies in vaccinated people at risk of AD, we generated a universal vaccine platform, MultiTEP, and, based on it, developed a DNA vaccine, AV-1959D, targeting pathological Aβ, completed IND enabling studies, and initiated a Phase I clinical trial with early AD volunteers. Our current pilot study combined our advanced MultiTEP technology with a novel mRNA approach to develop an mRNA vaccine encapsulated in lipid-based nanoparticles (LNPs), AV-1959LR. Here, we report our initial findings on the immunogenicity of 1959LR in mice and non-human primates, comparing it with the immunogenicity of its DNA counterpart, AV-1959D.

High Concentration of Anti-SARS-CoV-2 Antibodies 2 Years after COVID-19 Vaccination Stems Not Only from Boosters but Also from Widespread, Often Unrecognized, Contact with the Virus.

This study follows 99 subjects vaccinated with Pfizer/BioNTech COVID-19 vaccines over two years, with particular focus on the last year of observation (between days 360 and 720). The response to the vaccination was assessed with Diasorin's SARS-CoV-2 TrimericSpike IgG. Screening for SARS-CoV-2 infection was performed with Abbott's SARS-CoV-2 Nucleocapsid IgG immunoassay. Data from questionnaires were also analyzed. Two years after the first vaccine dose administration, 100% of the subjects were positive for anti-spike SARS-CoV-2 IgG and the median antibody level was still high (3600 BAU/mL), dropping insignificantly over the last year. Simultaneously, a substantial increase in seropositivity in anti-nucleocapsid SARS-CoV-2 IgG was noted, reaching 33%. There was no statistically significant agreement between anti-N seropositivity and reported COVID-19. Higher anti-spike concentrations and lower COVID-19 incidence was seen in the older vaccinees. It was noted that only subjects boosted between days 360 and 720 showed an increase in anti-spike IgG concentrations. The higher antibody concentrations (median 7440 BAU/mL) on day 360 were noted in participants not infected over the following year. Vaccination, including booster administrations, and natural, even unrecognized, contact with SARS-CoV-2 entwined two years after the primary vaccination, leading to high anti-spike antibody concentrations.

Exploring the possible link between the spike protein immunoglobulin G4 antibodies and cancer progression

Repeated inoculation with messenger RNA (mRNA) vaccines elicits immunoglobulin G4 (IgG4) antibody production. Such an increase in the concentration of specific and non-specific IgG4 antibodies allows the growth of some types of cancer by blocking the activation of effector immune cells. This work proposes the hypothesis that cancer growth may be indirectly promoted by increased concentrations of non-specific IgG4 antibodies by the following mechanisms: 1) IgG4 antibodies can bind to anti-tumor IgG1 antibodies and block their interaction with receptors located on effector cells, thus preventing the destruction of cancer cells, 2) IgG4 can interact with fragment crystallizable gamma receptor IIb (FcγRIIB) inhibitory receptors, thus reducing effector functions of innate immune cells, and 3) targeting of specific epitopes by IgG4 could be oncogenic by inducing the production of a microenvironment that can promote cancer development. This article reviews the supporting literature and suggests several experimental protocols to evaluate this hypothesis in the context of repeated inoculation with mRNA vaccines. Additionally, this work proposes some management options aimed at reducing the unfavorable molecular consequences that could mediate cancer development when encountering high concentrations of IgG4 antibodies.

Concentration-Dependent Diffusion of Monoclonal Antibodies: Underlying Mechanisms of Anomalous Diffusion.

The development, storage, transport, and subcutaneous delivery of highly concentrated monoclonal antibody formulations pose significant challenges due to the high solution viscosity and low diffusion of the antibody molecules in crowded environments. These issues often stem from the self-associating behavior of the antibody molecules, potentially leading to aggregation. In this work, we used a dissipative particle dynamics-based coarse-grained model to investigate the diffusion behavior of IgG1 antibody molecules in aqueous solutions with 15 and 32 mM NaCl and antibody concentrations ranging from 10 to 400 mg/mL. We determined the coarse-grained interaction parameters by matching the calculated structure factor with the computational and experimental data from the literature. Our results indicate Fickian diffusion for antibody concentrations of 10 and 25 mg/mL and anomalous diffusion for concentrations exceeding 50 mg/mL. The anomalous diffusion was observed for ∼0.33 to 0.4 μs, followed by Fickian diffusion for all antibody concentrations. We observed a strong linear correlation between the diffusion behavior of the antibody molecules (diffusion coefficient D and anomalous diffusion exponent α) and the amount of aggregates present in the solution and between the amount of aggregates and the Coulomb interaction energy. The investigation of underlying mechanisms for anomalous diffusion revealed that in crowded environments at high antibody concentrations, the attractive interaction between electrostatically complementary regions of the antibody molecules could further bring the neighboring molecules closer to one another, ultimately resulting in aggregate formation. Further, the Coulomb attraction can continue to draw more molecules together, forming larger aggregates.

Flow Cytometry-Based Measurement of Antibodies Specific for Cell Surface-Expressed Folded SARS-CoV-2 Receptor-Binding Domains.

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has now become endemic and is currently one of the important respiratory virus infections regularly affecting mankind. The assessment of immunity against SARS-CoV-2 and its variants is important for guiding active and passive immunization and SARS-CoV-2-specific treatment strategies. We here devised a novel flow cytometry-based diagnostic platform for the assessment of immunity against cell-bound virus antigens. This platform is based on a collection of HEK-293T cell lines which, as exemplified in our study, stably express the receptor-binding domains (RBDs) of the SARS-CoV-2 S-proteins of eight major SARS-CoV-2 variants, ranging from Wuhan-Hu-1 to Omicron. RBD-expressing cell lines stably display comparable levels of RBD on the surface of HEK-293T cells, as shown with anti-FLAG-tag antibodies directed against a N-terminally introduced 3x-FLAG sequence while the functionality of RBD was proven by ACE2 binding. We exemplify the usefulness and specificity of the cell-based test by direct binding of IgG and IgA antibodies of SARS-CoV-2-exposed and/or vaccinated individuals in which the assay shows a wide linear performance range both at very low and very high serum antibody concentrations. In another application, i.e., antibody adsorption studies, the test proved to be a powerful tool for measuring the ratios of individual variant-specific antibodies. We have established a toolbox for measuring SARS-CoV-2-specific immunity against cell-bound virus antigens, which may be considered as an important addition to the armamentarium of SARS-CoV-2-specific diagnostic tests, allowing flexible and quick adaptation to new variants of concern.

Clinical consequences of infliximab immunogenicity and the effect of proactive therapeutic drug monitoring: exploratory analyses of the randomised, controlled NOR-DRUM trials

Antidrug antibodies to TNF inhibitors might affect clinical outcomes. Proactive therapeutic drug monitoring allows for early detection of antidrug antibodies and might reduce negative clinical consequences. We aimed to explore how antidrug antibodies to the TNF inhibitor infliximab influence treatment outcomes, and to assess the effect of proactive therapeutic drug monitoring. This was a predefined exploratory analysis of data from the randomised, controlled NOR-DRUM trials. The trials were conducted in rheumatology, gastroenterology, and dermatology departments at 21 Norwegian hospitals. Adult patients (aged 18-75 years) with immune-mediated inflammatory diseases were randomly assigned to proactive therapeutic drug monitoring or standard infliximab dosing in the NOR-DRUM A trial (30-week follow-up) and the NOR-DRUM B trial (52-week follow-up). Antidrug antibodies were assessed with a drug-sensitive assay before each infusion. The outcomes of remission (at week 30), disease worsening (during 52 weeks), infusion reactions, and infliximab discontinuation were assessed according to the presence of antidrug antibodies and use of therapeutic drug monitoring. Between March 1, 2017, and Dec 12, 2019, 616 patients were included in the NOR-DRUM trials, of whom 615 had at least one serum infliximab and antidrug antibody assessment and were included in the present analyses. Mean age was 45 years (IQR 32-56), 305 (50%) patients were women, and 310 (50%) patients were men. Antidrug antibodies were detected in 147 (24%) patients. Remission at week 30 occurred in 25 (35%) of 72 patients with antidrug antibodies and 180 (54%) of 335 without antidrug antibodies (risk ratio 0·62 [95% CI 0·45-0·86]; p=0·0037). In patients with antidrug antibodies compared with patients without antidrug antibodies, higher rates were found for: disease worsening over 52 weeks (0·76 per person-year vs 0· 35 per person-year, hazard ratio [HR] 2·02 [95% CI 1·33-3·07]; p=0·0009), infusion reactions (0·16 per person-year vs 0·03 per person-year, HR 17·02 [6·98-41·47]; p<0·0001), and infliximab discontinuation (1·00 per person-year vs 0·20 per person-year, HR 6·64 [4·84-9·11]; p<0·0001). These associations were more pronounced in patients with high concentrations of antidrug antibodies than in those with low concentrations of antidrug antibodies. Independent of antibody status, therapeutic drug monitoring was associated with a lower risk of disease worsening (HR 0·41 [0·29-0·59]; p=0·0001) or an infusion reaction (HR 0·30 [0·12-0·73]; p=0·0076), and was associated with an increase in the rate of infliximab discontinuation (HR 1·37 [1·02-1·83]; p=0·037). In patients where antidrug antibodies were detected, remission was less likely to be reached and sustained, and infusion reaction or discontinuation of infliximab was more likely. Timely detection of antidrug antibodies by proactive therapeutic drug monitoring facilitated treatment decisions that reduced the negative consequences, both regarding infliximab effectiveness and safety. This highlights the role of proactive therapeutic drug monitoring in optimising infliximab therapy. Inter-regional KLINBEFORSK grants and South-Eastern Norway Regional Health Authority grants.

Anti-RBD antibody quantitation after vaccination against Covid-19 among the elderly in 2021-2022

ABSTRACT Background: The study aims to describe the concentration of binding antibodies after COVID-19 vaccination in the elderly in Hanoi and Hung Yen in 2021-2022 and evaluate some related factors. Methods: A prospective cohort study of 205 people aged &gt;= 60 vaccinated with AstraZeneca was conducted in COVID-19 vaccination facilities at Hanoi Medical University Hospital, ALH Nursing Home, Xuan Quan in Van Giang district, Hung Yen province from 9/2021 to 5/2022. The sCOVG test was used to evaluate the concentration of anti-RBD IgG binding antibodies at 7-time points. Results: Antibod concentrations peaked 14 days after the second dose (14.8 IU/ml), and gradually decreased until 3 months after the second dose. However, after the third dose, antibody concentrations increased again (60.24 IU/ml). Women had higher antibody concentrations than men when comparing the median antibody concentration 14 days after the first injection (7.08 vs 3.95 IU/ml) and 14 days after the second injection (32.27 vs. 16.60 IU/ml). People without a history of allergies had higher antibody concentrations than those with a history of allergies when comparing the median at 56 days after the second dose (7 vs. 5 IU/ml). Conclusion: Therefore, we recommend that people pay attention to vaccinating the third dose of the COVID-19 vaccine for elderly people who have not been vaccinated with this vaccine, especially men and elderly with allergies, to minimize the prevalence and mortality. Keywords: Anti-RBD, COVID-19 vaccine, AstraZeneca, Pfizer, elderly

Development of AAV-delivered broadly neutralizing anti-human ACE2 antibodies against SARS-CoV-2 variants

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in the emergence of new variants that are resistant to existing vaccines and therapeutic antibodies, has raised the need for novel strategies to combat the persistent global COVID-19 epidemic. In this study, a monoclonal anti-human angiotensin-converting enzyme 2 (hACE2) antibody, ch2H2, was isolated and humanized to block the viral receptor-binding domain (RBD) binding to hACE2, the major entry receptor of SARS-CoV-2. This antibody targets the RBD-binding site on the N terminus of hACE2 and has a high binding affinity to outcompete the RBD. Invitro, ch2H2 antibody showed potent inhibitory activity against multiple SARS-CoV-2 variants, including the most antigenically drifted and immune-evading variant Omicron. Invivo, adeno-associated virus (AAV)-mediated delivery enabled a sustained expression of monoclonal antibody (mAb) ch2H2, generating a high concentration of antibodies in mice. A single administration of AAV-delivered mAb ch2H2 significantly reduced viral RNA load and infectious virions and mitigated pulmonary pathological changes in mice challenged with SARS-CoV-2 Omicron BA.5 subvariant. Collectively, the results suggest that AAV-delivered hACE2-blocking antibody provides a promising approach for developing broad-spectrum antivirals against SARS-CoV-2 and potentially other hACE2-dependent pathogens that may emerge in the future.

Viral Encephalitis (Human Herpes Virus Type 6) after COVID-19 in a Child: Clinical Case

Background. Immune system disorders early after COVID-19 are associated with high risk of other infections development, including viral ones. Their diagnosis is complicated especially in the absence of clinical symptoms of primary infection and alongside with serious disease course. There are no reports on encephalitis development due to reactivation of latent viral infection.Clinical case description. Girl, 4 years-old, had psycho-neurological symptoms followed by tonic seizures on the next day. The child was hospitalized on the 3rd day after disease onset with preliminary diagnosis of viral encephalitis. The child has contacted with patients with laboratory-confirmed new coronavirus infection 3-4 weeks before the disease onset, later she had signs of mild respiratory infection (no examination of SARS-CoV-2 was carried out). Autoimmune nature of central nervous system injury was suspected after excluding a wide range of infections (negative PCR results for SARS-CoV-2, cytomegalovirus, herpes simplex virus, Epstein-Barr virus, toxoplasma, enterovirus), however it was not confirmed later on. Human herpes virus type 6 was revealed via blood tests and oropharyngeal swаb on the 15th day of disease. High concentration of IgG antibodies to SARS-CoV-2 was found was revealed as well. Treatment (antibacterial, anticonvulsant, anticoagulant, antiviral, immunosupportive, and sedative therapy, glucocorticosteroids) did not achieve significant improvement. Brain MRI (on the 23rd day of the disease) has shown leukoencephalopathy zones in subcortical white matter of convexital surfaces of parietal and occipital lobes, subatrophic changes in white matter of cerebral hemispheres with moderate vicarious enlargement of the subarachnoid spaces. Disease progression led to patient’s death on the 32nd day after first signs appearance.Conclusion. The development of severe viral encephalitis (as a result of primary herpes virus infection or its reactivation) in the early period after mild COVID-19 is shown. Its cause-effect relations require further examination.

Postinfectious and Postvaccinal Humoral Immune Response to SARS-CoV-2 in Adults: Qualitative and Quantitative Assessment

Relevance. Serological studies play an important role in assessing the spread of SARS-CoV-2 and formation of post-infection and post-vaccination immune response.The Aims aim of the study was a comparative assessment of seroprevalence and concentration of antibodies to SARS-CoV-2 at 3–6 months after infection or vaccination.Materials &amp; Methods. For the presence of total IgM and IgG antibodies to RBD fragment of the SARS-CoV-2 S protein, the blood sera of 1331 people aged 18-70 years were examined, of which 334 had COVID-19 3–6 months before the study, 305 did not have COVID-19 and were vaccinated (using Sputnik V, Russia, or Sinopharm, PRC) 3–6 months before the study, 692 people were not ill and were not vaccinated. A quantitative assessment of IgG antibodies to the full-size S-protein of SARS-CoV-2 was performed for 435 samples.Results. The proportion of seropositive individuals 3–6 months after COVID-19 or after vaccination did not differ: 92.5% and 93.8% of the corresponding group had antibodies. Among the non-ill and unvaccinated, 45.7% also had specific antibodies, which indicates a high level of asymptomatic infection with SARS-CoV-2. The group of vaccinated was also examined immediately before the introduction of the vaccine, and 39.7% of them already had specific antibodies due to asymptomatic infection with SARS-CoV-2. The median concentration of antibodies in the group of COVID-19 was statistically significantly higher than in asymptomatically infected (50.9 AE/ml versus 29.1 AE/ml). The largest proportion of seropositive individuals (100.0%) and the highest concentration of antibodies (110 AE/ml) were detected in the group of vaccinated who had pre-existing antibodies.Conclusion. Infection with the SARS-CoV-2 is characterized by a high frequency of subclinical course. Asymptomatic infection induced a weaker immune response compared to symptomatic COVID-19 or vaccination. Hybrid immunity caused by natural infection with SARS-CoV-2 and subsequent vaccination was the most persistent and pronounced.

Prevalence of anti‐egg albumin antibodies in cerebrospinal fluid of patients with mild and severe Alzheimer’s Disease. Correlation with gender and incidence of anti‐casein antibodies and AGEs.

AbstractBackgroundAlzheimer’s Disease (A.D.) is a multifactorial process. Advanced glycation end products (AGEs) have been correlated with disease development1. Additionally, high concentrations of antibodies against the food derived antigens egg‐albumin and bovine casein, have been detected in patients with Alzheimer’s disease in preliminary research presented by our team, previously (AAIC 2018).In the present study, antibodies against egg‐albumin and bovine casein as well as AGEs were detected in the cerebrospinal fluid of 36 patients with mild and 35 patients with severe Alzheimer’s Disease and 13 healthy individuals and a correlation between the measured parameters and sample properties was attempted.MethodELISA plates pre‐treated with highly hydrophilic microlon resin were used for the purpose of this study2. Egg‐albumin or bovine casein antigens were attached at the ELISA plates for the measurement of antibodies. Additionally, polyclonal antibodies against multiple AGE products were used to detect attached sample CSF AGEs.ResultAccording to the results, 48,6% of of the samples of patients with severe AD had anti‐egg albumin concentration higher than mean concentration of healthy idividuals+2SD (characterized as positive) compared to 8.3% of positive samples in patients with mild disease. An overall 265% increase in mean concentration was observed in severe compared to mild patients, indicating association with severity. The observed difference was significant at p = 0.01 according to mann witney U test. Lower anti‐egg albumin concentrations were observed in female samples of either mild or severe disease (Figure 1). Much lower incidence of anti‐casein antibody positive samples was found in in severe AD (5.7% positive in severe versus 0% in mild AD). A slight, not statisticaly significant, increase in mean anti‐casein antibodies concentration (23.7%) and AGEs (16.2%) was observed in severe compared to mild disease with the higher concentrations also detected in the most positive to anti‐egg albumin samples.ConclusionThe results indicated a potential correlation of antibodies against egg‐albumin with the severity of Alzheimer’s disease with increased incidence in male patients. A lower correlation was observed in case of anti‐casein antibodies and AGEs.

Effect of immunization during pregnancy and pre-existing immunity on diphtheria-tetanus-acellular pertussis vaccine responses in infants

ABSTRACT Immunization during pregnancy (IP) against pertussis is recommended in many countries to protect infants. Although maternal antibodies can influence the infants’ antibody responses to primary vaccinations, their effect on the development of functional antibodies and B cells remain poorly studied. We investigated the maternal immune response to IP and the effect of IP and pre-existing antibodies on infants’ primary vaccine responses in an open-label, non-randomized trial. Forty-seven mothers received tetanus-diphtheria-acellular pertussis (Tdap) vaccine during pregnancy, and 22 mothers were included as controls. Sixty-nine infants received primary doses of DTaP at three and five months of age. Geometric mean concentrations of antibodies to pertussis toxin, filamentous haemagglutinin, pertactin, diphtheria, and tetanus toxins, pertussis toxin neutralizing antibodies (PTNAs), and plasma and memory B-cell frequencies were studied at delivery, and at three, five and six months. Levels of antibodies, PTNAs, and frequencies of memory B-cells were significantly increased at delivery and up to six months after in mothers with IP compared to those without IP (all p < 0.05, except for PT-specific memory B-cells). In vaccinated pregnant women, high pre-existing antibody levels were positively correlated with higher antibody responses after IP. IP blunted the infants’ antibody and plasma B-cell responses to all vaccine antigens, except for tetanus toxin. This blunting effect was the strongest in infants with high concentrations of maternal antibodies. In conclusion, IP resulted in significantly higher concentrations of antibodies in infants up to three months of age (all p < 0.05); but was associated with blunting of various infants’ vaccine responses.

The humoral and cellular response to mRNA SARS-CoV-2 vaccine is influenced by HLA polymorphisms.

Host genetic variability contributes to susceptibility to SARS-CoV-2 infection and COVID-19 evolution and the role of HLA system has not clearly emerged, suggesting the involvement of other factors. Studying response to vaccination with Spyke protein mRNA represents an ideal model to highlight whether the humoral or cellular responses are influenced by HLA. Four hundred and sixteen workers, vaccinated with Comirnaty beginning 2021, were selected within the Azienda Ospedaliera Universitaria "Città della Salute e della Scienza di Torino." The humoral response was determined with the LIAISON® kit, while the analysis of the cellular response was performed with the Quantiferon SARS-CoV-2 assay, for the S1 (receptor-binding domain; Ag1) and S1 and S2 (Ag2) subunits of the Spyke protein. Six HLA loci were typed by next-generation sequencing. Associations between HLA and vaccine response were performed with univariate and multivariate analyses. An association was found between A*03:01, B*40:02 and DPB1*06:01 and high antibody concentration and between A*24:02, B*08:01 and C*07:01 and low humoral responses. The haplotype HLA-A*01:01 ~ B1*08:01 ~ C*07:01 ~ DRB1*03:01 ~ DQB1*02:01 conferred an increased risk of low humoral response. Considering cellular responses, 50% of the vaccinated subjects responded against Ag1 and 59% against Ag2. Carriers of DRB1*15:01 displayed a higher cellular response both to Ag1 and Ag2 compared to the rest of the cohort. Similarly, DRB1*13:02 predisposed to a robust cellular response to Ag1 and Ag2, while DRB1*11:04 showed an opposite trend. Cellular and humoral responses to Comirnaty are influenced by HLA. Humoral response is mainly associated to class I alleles, with A*03:01, previously associated to protection against severe COVID-19, and response to vaccination, standing out. Cellular response predominantly involves class II alleles, with DRB1*15:01 and DPB1*13:01 prevailing. Affinity analysis for Spyke peptides is generally in line with the association results.

Hashimoto's Encephalopathy: Case Series and Literature Review.

To describe the clinical manifestations of Hashimoto's encephalopathy (HE) and discuss its pathogenesis in light of recent research. The pathogenesis of HE is uncertain. Available evidences point towards an autoimmune etiology due to vasculitis or other inflammatory process. Detection of thyroid antibodies - antithyroid peroxidase and anti-thyroglobulin are essential for diagnosis. Autoimmune encephalitis including Anti-IgLON5 disease needs to be excluded in suspected cases with appropriate tests for neuronal surface antibodies. Detection of thyroid autoantibodies is nonspecific, as these can be detected in some normal individuals and in other autoimmune diseases. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels in younger males with very high levels of thyroid antibodies. The role of the thyroid autoantibodies in the central nervous system (CNS) tissue damage remains unclear and these can act only as markers for diagnosis. Conversely, they have a role to play in determining the thyroid pathology - more glandular fibrosis associated with thyro-peroxidase antibody than with the thyroglobulin antibody. HE is a syndrome characterized by altered mental status, confusion, hallucinations, delusions, and sometimes seizures, in association with high serum anti-thyroid antibody concentration that is usually responsive to glucocorticoid therapy. Diagnosis requires the exclusion of other causes of encephalopathies and encephalitis including autoimmune encephalitis associated with neuronal surface antibodies and paraneoplastic ones. Diagnosis also is dependent on the demonstration of thyroid autoantibodies in serum. Since there is no direct pathophysiologic link between antithyroid antibodies, Hashimoto thyroiditis and the cerebral syndrome, the nomenclature HE could be misleading. The response to steroids led to a renaming of the syndrome to steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), though some cases do not respond to steroids. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels (IgG4-related disease). This is characterized by a higher incidence in men (5:1) than in women, onset at a younger age, more intense thyroid inflammation and higher antithyroid antibody titters. Such patients have excessive production of IgG4 + plasmacytes, which infiltrate various organs leading to their fibrosis and sclerosis, sometimes resulting in inflammatory tumors. HE is treated with corticosteroids along with treatment of the dysthyroid condition, if any. There are yet no guidelines regarding steroid dose and/or duration.

Persistence of Antibodies Six Months after Three COVID-19 mRNA Vaccine Doses in Patients with Inflammatory Bowel Disease.

Lay Summary We evaluated antibody concentrations 6 months after a third coronavirus disease 2019 messenger RNA vaccine dose in patients with inflammatory bowel diseases. Almost all patients had an antibody response, and those with a previous SARS-CoV-2 infection had higher antibody concentrations.