Low Antibody Levels Research Articles

Risk of low levels of blood group antibodies mediating hemolysis in ABO-incompatible neonates with negative three hemolysis tests.

To explore the risk of low-level blood group antibody-mediated hemolysis in ABO-incompatible newborns with negative three hemolysis tests, aiming to assist in the identification and management of neonatal jaundice. A retrospective case-control study was performed in 892 children with jaundice. The patients were divided into three groups: group I, ABO compatible, negative three hemolysis tests; group II, ABO incompatible, negative three hemolysis tests; and group III, ABO incompatible, positive three hemolysis tests. We analyzed the differences in clinical data, blood routine and biochemical laboratory results. (1) Patients in group II had higher levels of mean corpuscular volume (MCV), standard deviation of red blood cell volume distribution width (RDW-SD), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and bile acid (BA) than those in group I (P < 0.05). However, there were no statistically significant differences in the MCV, ALT, ALP and BA levels between groups II and III (P > 0.05). (2) Mean corpuscular hemoglobin concentration (MCHC) >359.5 g/L, cell volume distribution width (RDW-CV) >15.95%, and reticulocyte count (RET) >4.235% were identified as independent predictors of positive hemolysis test results (P < 0.001). The combination of MCHC, RDW-CV, and RET% yielded an AUC of 0.841. Low-level blood group antibody-mediated hemolysis may occur in ABO-incompatible neonates even when three hemolysis tests are negative. Changes in liver function parameters must be monitored. The combination of MCHC, RDW-CV, and RET% can be used to improve the detection rate of HDN.

Low Salivary IgA Levels Against PAc (361-386) as a Risk Factor for Root Caries in Older Adults.

This study aimed to assess the intricate relationship between salivary IgA antibody levels to PAc (361-386) (PPA), mutans streptococci colonization, and root caries development in older adults. This study included 307 participants aged 76 years residing in Niigata city, Japan. Clinical oral examinations were performed at baseline in 2004 and 1 year later, during which the total number of untreated and treated root caries was assessed using the root decayed, filled tooth (DFT) index. The stimulated saliva samples were collected using the spitting method during the baseline survey. Salivary IgA antibody levels to amino acid residues 361-386 of Streptococcus mutans PAc were quantified using an enzyme-linked immunosorbent assay. Statistical analyses, including the χ2 test, Mann-Whitney U test, and logistic regressions, were performed to examine the association of increased root DFT with the independent variables. Among the 307 participants (53.1% men), the mean root DFT at baseline was 3.77 ± 3.66, and 36.5% of the study sample exhibited increased root DFT after 1 year with a mean increment of 0.36 ± 0.48. Participants with increase in root DFT after 1 year had significantly higher rates of low PPA levels (≤ 25th percentile) than those without increased root DFT (p = 0.020). Low PPA levels (≤ 25th percentile) were significantly more likely to have an increased risk of root caries development compared with PPA levels > 25th percentile (adjusted OR: 1.88, 95% CI: 1.09-3.25). Low PPA levels and root caries incidence correlated significantly, suggesting that low levels of salivary IgA antibody to PAc (361-386) may serve as a risk factor for increased root caries in older adults.

Maternal Pertussis Immunization and Immunoglobulin G Levels in Early- to Late-Term and Preterm Infants

Maternal tetanus, diphtheria, and acellular pertussis (Tdap) vaccination protects newborns against severe pertussis. Data on transplacental antibody transfer on Tdap vaccination before 24 weeks' gestation remain scarce and are particularly relevant for preterm infants to increase the time interval for maternal antibody transfer. To assess noninferiority of anti-pertussis toxin (anti-PT) immunoglobulin G (IgG) antibody levels at age 2 months in early- to late-term infants following Tdap vaccination between 20 0/7 and 24 0/7 weeks' gestation compared with 30 0/7 and 33 0/7 weeks' gestation and compared with preterm infants. This prospective, multicenter cohort study included pregnant women aged 18 years or older in birthing centers and hospitals in the Netherlands between August 2019 and November 2021 who received Tdap vaccination between 20 0/7 and 24 0/7 weeks' gestation. Women with imminent premature birth were recruited if they had received maternal Tdap vaccination between 20 and 24 weeks' gestation. Blood samples were collected from mothers at delivery, from the umbilical cord, and from infants at age 2 months. Data from infants' blood samples at age 2 months were compared with a reference cohort (recruited between January 2014 and February 2016) of early- to late-term infants of the same age whose mothers had received Tdap vaccination between 30 0/7 and 33 0/7 weeks' gestation. Maternal Tdap vaccination between 20 0/7 and 24 0/7 weeks' gestation or 30 0/7 and 33 0/7 weeks' gestation. The primary outcome was the geometric mean concentration (GMC) of anti-PT IgG antibodies in early- to late-term infants (≥37 0/7 weeks' gestation) at age 2 months, comparing maternal Tdap vaccination between 20 0/7 and 24 0/7 weeks' vs 30 0/7 and 33 0/7 weeks' gestation (reference cohort). Anti-PT GMC in 2-month-old infants born preterm (<35 0/7 weeks' gestation) compared with early- to late-term infants after maternal Tdap vaccination between 20 and 24 weeks' gestation was a secondary outcome. In total, 221 women who delivered 239 offspring were enrolled in the study; 66 early- to late-term infants (median gestational age [GA], 40.6 weeks [IQR, 39.8-41.0 weeks]; 38 [57.6%] male) and 73 preterm infants (median GA, 32.1 weeks [IQR, 29.5-33.0 weeks]; 42 [54.5%] female) had blood samples collected at 2 months of age. Anti-PT GMC was 14.7 IU/mL (95% CI, 10.6-20.4 IU/mL) in early- to late-term infants following maternal Tdap vaccination between 20 0/7 and 24 0/7 weeks' gestation compared with 27.3 IU/mL (95% CI, 20.1-37.1 IU/mL) in 55 infants in the reference group (median GA, 40.3 [IQR, 39.1-41.0]; 33 [60.0%] female). The mean anti-PT GMC in preterm infants in the study group was 11.2 IU/mL (95% CI, 8.1-15.3 IU/mL) (P = .23 compared with early- to late-term infants). In this cohort study, 2-month-old preterm and early- to late-term infants showed significantly lower anti-PT antibody levels following maternal Tdap vaccination between 20 0/7 and 24 0/7 weeks' gestation compared with 30 0/7 and 33 0/7 weeks' gestation; preterm and early- to late-term infants had similar anti-PT antibody levels, but both groups showed significantly lower antibody levels compared with the reference group. Epidemiological research should investigate whether maternal Tdap vaccination before 24 weeks' gestation provides sufficient protection against clinical pertussis, particularly in preterm infants, as long as no correlate of protection is available.

Predictors of Therapy Success in Weekly Adalimumab for Refractory Uveitis: A Retrospective Cohort Study

PurposeTo determine predictors of treatment success after dose escalation of adalimumab, including measurement of anti-adalimumab antibodies as a predictor of success DesignRetrospective clinical cohort study SettingSingle-center academic institution Study PopulationPatients with noninfectious uveitis who were inadequately controlled or developed recurrent disease on biweekly adalimumab and required dose escalation or therapy modification Observation ProceduresPatients who had anti-adalimumab antibodies checked with resultant low to intermediate levels were compared to patients who had no testing performed prior to adalimumab dose escalation. Of note, patients with testing and resultant high levels of anti-adalimumab antibodies were not escalated. Predictors of escalation success and utility of antibody testing prior to escalation were analyzed using Kaplan Meier survival analysis and Cox proportional hazard models. Main Outcome MeasuresTreatment success defined as anterior chamber grade ≤0.5+ cell, topical corticosteroids ≤1 drop/day, oral prednisone ≤5 mg/day, resolution of macular edema, and resolution of angiographic signs of inflammation without any addition or escalation of therapy. Results24 patients had antibodies tested with low to intermediate levels (average: 32.3 ng/mL, range: 0 – 154), while 41 did not have antibody testing. A greater treatment success rate post escalation was observed among the “low antibody” group compared to the “no testing” group (HR: 2.63, standard error: 1.19, p=0.031, 95% CI 1.09 – 6.37). Among the entire cohort, patients with panuveitis (n = 14) had a lower treatment success rate compared to the reference of anterior uveitis (n = 26) (HR: 0.09, standard error: 0.11, p = 0.05, 95% CI 0.01 – 0.99). ConclusionsPatients with low anti-adalimumab antibodies had a greater treatment success compared to patients in whom antibodies were not checked. This suggests a utility to checking antibodies prior to dose escalation and that low levels of antibodies may confer a success advantage. Overall, patients with panuveitis had a lower rate of success after escalation while patients with anterior uveitis patients had a very high rate of success suggesting that certain disease characteristics may guide clinicians when determining who to escalate versus changing therapy.

Pediatric antibody responses to SARS-CoV-2 after infection and vaccination in Calgary, Canada

BackgroundThere are few reports of longitudinal serologic responses in children following Sars-CoV-2 infection and vaccination. This study describes longitudinal SARS-CoV-2 antibody responses following infection, vaccination, or both (hybrid immunity) in a cohort of Canadian children. The objectives of our study were to compare antibody levels following SARS-CoV-2 infection, vaccination, and hybrid immunity and to examine antibody decline after final antigen exposure.MethodsThe Alberta Childhood COVID-19 Cohort (AB3C) study was a prospective longitudinal cohort study conducted from July 2020 to September 2022 with repeat sampling across 5 visits. Children under 18 years of age were enrolled for serial measurement of antibody responses to SARS-CoV-2 virus vaccine and infection.ResultsThe final sample size was 919; participants were 50.5% female, 48.2% were > 12 years and 88.5% were white ethnicity. The median peak spike IgG level of those with only infection was not different from those with no vaccination or infection (233 AU/mL (IQR: 99–944 AU/mL) vs. 3 AU/mL (IQR: 1–5 AU/mL; P = 0.1765). Participants with infections after vaccination had higher IgG levels than those where infection preceded vaccination (median: 36,660 (IQR: 22,084 − 40,000 AU/mL) vs. 17,461 AU/mL (IQR: 10,617 − 33,212 AU/mL); P < 0.0001). In a linear mixed methods model, children with infection-only had low levels of antibody that stayed stable over the study duration without further antigen exposures. Those with infection after vaccination had the slowest rate of antibody decline over time at 4% (95%CI: 2-5%) per week, compared with children where infection preceded vaccine 7% (95%CI: 6-8%) per week.ConclusionsChildren with hybrid immunity conferred through vaccination (2 + doses) followed by a SARS-CoV-2 infection had the highest and longest lasting antibody levels, compared to children who had an infection followed by vaccination, vaccination-only, or infection-only. The longer-term clinical importance of these findings, related to prevention of repeated infections and severe outcomes and need for further vaccine doses, is not yet known.

Hepatitis B screening in hematology patients receiving intravenous immunoglobulin.

Transient positivity for hepatitis B core antibody (Anti-HBc) following intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin exposure is a well-described phenomenon. The aim of this study was to retrospectively review Hepatitis B viral screening practices in IVIG recipients in a hematology specific cohort at a single center. Electronic databases were analyzed to identify all hematology patients who received IVIG from September 2022 to March 2022 at a single Irish center (n = 43). The proportion of patients that had a baseline anti-HBc tested prior to IVIG receipt was assessed as well as the proportion of patients that developed a transiently positive anti-HBc following IVIG exposure. Data were also collected relating to signal cut-off ratios in patients with detectable anti-HBc post-IVIG. 58.1% of patients had at least one serological hepatitis B viral test sent prior to IVIG exposure. Anti-HBc was the least common serological investigation performed prior to IVIG exposure (21% of recipients). A positive or equivocal "low level antibody" was identified in 15% of recipients and this was proven to be transient in all cases. The minority of hematology patients had a baseline anti-HBc assessed prior to IVIG exposure. All patients in this study had the potential to require further immunosuppressive therapies, which could be limited by a misleading anti-HBc result. We therefore advocate for baseline anti-HBc testing to be performed prior to IVIG exposure in hematology patients and for cautious interpretation of anti-HBc results taking into account signal cut-off ratios post-IVIG exposure.

IL-4 acts on skin-derived dendritic cells to promote the TH2 response to cutaneous sensitization and the development of allergic skin inflammation

Atopic dermatitis is characterized by scratching and a TH2-dominated local and systemic response to cutaneously encountered antigens. Dendritic cells (DCs) capture antigens in the skin and rapidly migrate to draining lymph nodes (dLNs) where they drive the differentiation of antigen-specific naive T cells. We sought to determine whether non-T-cell-derived IL-4 acts on skin-derived DCs to promote the TH2 response to cutaneously encountered antigen and allergic skin inflammation. DCs from dLNs of ovalbumin (OVA)-exposed skin were analyzed by flow cytometry and for their ability to polarize OVA-specific naive CD4+ T cells. Skin inflammation following epicutaneous sensitization of tape-stripped skin was assessed by flow cytometry of skin cells and real-time quantitative PCR of cytokines. Cytokine secretion and antibody levels were evaluated by ELISA. Scratching upregulated IL4 expression in human skin. Similarly, tape stripping caused rapid basophil-dependent upregulation of cutaneous Il4 expression in mouse skin. Invitro treatment of DCs from skin dLNs with IL-4 promoted their capacity to drive TH2 differentiation. DCs from dLNs of OVA-sensitized skin of Il4-/- mice and CD11c-CreIl4rflox/- mice, which lack IL-4Rα expression in DCs (DCΔ/Δll4ra mice), were impaired in their capacity to drive TH2 polarization compared with DCs from controls. Importantly, OVA-sensitized DCΔ/Δll4ra mice demonstrated impaired allergic skin inflammation and OVA-specific systemic TH2 response evidenced by reduced TH2 cytokine secretion by OVA-stimulated splenocytes and lower levels of OVA-specific IgE and IgG1 antibodies, compared with controls. Mechanical skin injury causes basophil-dependent upregulation of cutaneous IL-4. IL-4 acts on skin DCs that capture antigen and migrate to dLNs to promote their capacity for TH2 polarization and drive allergic skin inflammation.

Combination of high anti-SKI and low anti-TMED5 antibody levels is preferable prognostic factor in esophageal carcinoma.

Given that esophageal cancer is highly malignant, the discovery of novel prognostic markers is eagerly awaited. We performed serological identification of antigens by recombinant cDNA expression cloning (SEREX) and identified SKI proto-oncogene protein and transmembrane p24 trafficking protein 5 (TMED5) as antigens recognized by serum IgG antibodies in patients with esophageal carcinoma. SKI and TMED5 proteins were expressed in Escherichia coli, purified by affinity chromatography, and used as antigens. The serum anti-SKI antibody (s-SKI-Ab) and anti-TMED5 antibody (s-TMED5-Ab) levels were significantly higher in 192 patients with esophageal carcinoma than in 96 healthy donors. The presence of s-SKI-Abs and s-TMED5-Abs in the patients' sera was confirmed by western blotting. Immunohistochemical staining showed that the TMED5 protein was highly expressed in the cytoplasm and nuclear compartments of the esophageal squamous cell carcinoma tissues, whereas the SKI protein was localized predominantly in the nuclei. Regarding the overall survival in 91 patients who underwent radical surgery, the s-SKI-Ab-positive and s-TMED5-Ab-negative statuses were significantly associated with a favorable prognosis. Additionally, the combination of s-SKI-Ab-positive and s-TMED5-Ab-negative cases showed an even clearer difference in overall survival as compared with that of s-SKI-Ab-negative and s-TMED5-Ab-positive cases. The s-SKI-Ab and s-TMED5-Ab biomarkers are useful for diagnosing esophageal carcinoma and distinguishing between favorable and poor prognoses.

Comparison of Hepatitis B Surface Antibody Levels After Vaccination With Combined One Dose of Hexavalent Vaccine and Two Doses of Pentavalent Vaccine Versus Three Doses of Pentavalent Vaccine.

Vaccination can effectively prevent hepatitis B virus (HBV) infection. Vaccination with 3 doses of hexavalent HBV-containing vaccines led to a higher Hepatitis B surface antibody (anti-HBs) antibody level than vaccination with 3 doses of pentavalent HBV-containing vaccines. Whether the substitution of one dose of hexavalent HBV-containing vaccine in the pentavalent regimen could lead to a higher anti-HBs antibody level remains unknown. A randomized, open-label controlled trial was conducted. Infants aged 30-120 days were randomly assigned to either a combined hexavalent/pentavalent regimen (hexavalent HBV-containing vaccine at 2 months of age and pentavalent HBV-containing vaccine at 4 and 6 months of age) or a 3-dose pentavalent regimen (pentavalent HBV-containing vaccine at 2, 4, and 6 months of age). Anti-HBs antibody levels were measured 3-6 months after the last vaccination. Seventy-six infants were enrolled, 38 in each group. The geometric mean of anti-HBs antibody levels in the combined hexavalent/pentavalent group was significantly higher than that of the 3-dose pentavalent group [316.2 mIU/mL (95% CI: 173.8-575.4 mIU/mL) versus 81.3 mIU/mL (95% CI: 38.9-169.8 mIU/mL), P = 0.006]. By multivariate analysis, the combined hexavalent/pentavalent regimen (coefficient 0.57; P = 0.003) was associated with higher anti-HBs antibody levels, while body weight <10th percentile (coefficient -0.85; P = 0.006) and receiving concomitant pneumococcal conjugated vaccines (coefficient -0.65; P = 0.001) were associated with lower anti-HBs antibody levels. Substituting the first dose with a hexavalent HBV-containing vaccine in the pentavalent regimen for HBV vaccination led to higher anti-HBs antibody levels in infants. Concomitant pneumococcal conjugated vaccine administration may have an adverse impact on anti-HBs antibody level.

Survey on colostrum management by German dairy farmers focusing on frozen colostrum storage

Because calves are born with low levels of antibodies, effective colostrum management is one of the most critical factors for successful calf rearing. A timely and adequate supply of sufficiently high-quality colostrum immediately after birth is essential to ensure the passive immunization of calves. Frozen colostrum reserves are recommended to fulfill the immunological and nutrient requirements of newborn calves, even in exceptional situations; however, the implementation rates on German dairy farms and challenges of realization remain unclear. A 33-question online survey, focused on frozen colostrum reserves, was developed to obtain an overview of colostrum management practices on German dairy farms. The questionnaire was divided into 3 sections: 1. personal data; 2. farm characteristics; 3. colostrum management. Of the 155 responses we received, 63.9% were from female farmers, and 35.5% were from male farmers. Conventional farming was practiced on 89.0% of farms, and organic farming was practiced on 7.1% of farms. Of the respondents, 89.0% froze colostrum. The main reasons for freezing colostrum were: 1. the dam does not produce enough colostrum; 2. the dam cannot be milked; or 3. in cases where the dam dies during birth. Farmers primarily froze colostrum from cows during their third to fifth lactation. Before freezing, 33.1% of the respondents measured indicators in the colostrum to estimate Ig concentrations, whereas 2.3% determined the colostrum quality after freezing. Reusable and disposable PET deposits (23.1%, 22.3%) and ColostroBags (20.0%) were the primary containers used to freeze colostrum. The main reasons for not freezing colostrum were the high labor intensity and the availability of fresh colostrum from other cows. Thawing methods included buckets (47.7%) and professional water baths (13.8%). The survey identified areas in which improved knowledge transfer could enhance colostrum management. Furthermore, there appeared to be a lack of specific, feasible instructions for employees concerning the practical implementation of colostrum management. Most importantly, the regular determination and documentation of Ig concentrations should be emphasized. The added value of stored colostrum, relative to a greater workload, should also be promoted, particularly on smaller farms.

Quantity and Quality of Naturally Acquired Antibody Immunity to the Pneumococcal Proteome Throughout Life.

Young children and older adults are susceptible for invasive pneumococcal disease (IPD) caused by Streptococcus pneumoniae. Pneumococcal protein-specific antibodies play a protective role against IPD; however, not much is known about the pace of acquisition, maturation, and maintenance of these antibodies throughout life. Immunoglobulin G (IgG) and IgA levels, avidity, and/or specificity to the pneumococcal proteome in serum and saliva from healthy young children, adults, and older adults, with known carriage status, were measured by enzyme-linked immunosorbent assay (ELISA) and 2-dimensional western blotting against ΔcpsTIGR4. Eleven-month-old children, the youngest age group tested, had the lowest pneumococcal proteome-specific IgG and IgA levels and avidity in serum and saliva, followed by 24-month-old children and were further elevated in adult groups. Among adult groups, the parents had the highest serum and saliva IgG and IgA antibody levels. In children, antibody levels and avidity correlated with daycare attendance and presence of siblings, posing as proxy for exposure and immunization. Immunodominance patterns slightly varied throughout life. Humoral immunity against the pneumococcal proteome is acquired through multiple episodes of pneumococcal exposure. Low-level and low-avidity antiproteome antibody profiles in young children may contribute to their IPD susceptibility, while in overall antiproteome antibody-proficient older adults other factors likely play a role.

Seroepidemiology of measles and rubella among Hong Kong young adults and the humoral responses of an MMR booster among participants with low antibody levels.

Some individuals may not retain adequate immunity against measles and rubella years after two doses of measles, mumps, and rubella (MMR) vaccination due to vaccine failure. This study aimed to investigate the rates of vaccine failure and seroconversion by administering an MMR booster to young adults. We first assessed measles and rubella antibody levels using the Luminex multiplex assay, VIDAS IgG assay, and plaque reduction neutralization test (PRNT) among individuals aged 18-30 years old who had received two doses of MMR vaccine. Participants with low measles and/or rubella antibody levels as confirmed by VIDAS received an MMR booster. Antibody levels were measured at 1-month post-booster. Among 791 participants, the measles and rubella seroprevalence rates were 94.7% (95% CI: 92.9%-96.0%) and 97.3% (95% CI: 96.0%-98.3%), respectively. Lower seroprevalence rates were observed among older participants. 113 participants who received an MMR booster acquired higher measles and rubella antibody levels at 1-month post-booster compared to baseline. Although measles and rubella vaccine failures were observed among 5.3% and 2.7% of young adults, respectively, an MMR booster triggered a significant antibody response.

Exploring the Impact of mRNA Modifications on Translation Efficiency and Immune Tolerance to Self-Antigens.

Therapeutic modified mRNAs are being developed for a broad range of human diseases. However, the impact of potential miscoding of modified mRNAs on self-tolerance remains unknown. Additionally, more studies are needed to explore the effects of nucleoside alkylation on translation. While all six tested modifications are tolerated as substrates by T7 RNA polymerase and inhibited mRNA immunogenicity, the translation efficiency varied significantly depending on the type of modification. In contrast to methylation, ethylation at the N1 position of pseudouridine (Ψ) hindered translation, suggesting that the C5-C1' glycosidic bond alone is not a critical element for high translation. Inhibition of mRNA translation was also observed with 5-methoxyuridine modification. However, this inhibition was partially alleviated through the optimization of mRNA coding sequences. BALB/c mice immunized with syngeneic ψ-modified mRNA encoding for Wilms' tumor antigen-1 (WT1) developed a low but significant level of anti-WT1 IgG antibodies compared to those immunized with either unmodified or N1-methyl ψ-modified mRNA. Overall, the data indicate that adding a simple ethyl group (-CH2CH3) at the N1 position of ψ has a major negative effect on translation despite its reduced immunogenicity. Additionally, mRNA containing Ψ may alter translation fidelity at certain codons, which could lead to a breakdown of immune tolerance to self-antigens. This concern should be taken into account during gene replacement therapies, although it could benefit mRNA-based vaccines by generating a diverse repertoire of antigens.

Reference Material Production and Milk Protein Concentration as Elements to Improve Bluetongue Serological Diagnosis in Bulk Tank Milk.

The serological surveillance of bluetongue in bulk tank milk is an efficient and cost-effective method for the early detection of bluetongue virus incursions in unvaccinated free areas of the disease. In addition, the availability of standardized and reliable reagents and refined diagnostic procedures with high sensitivity and specificity are essential for surveillance purposes. However, no available reference materials for bluetongue virus serological surveillance in bulk tank milk exist. This study shows the production and characterization of reference material for the implementation of a commercially available bluetongue milk ELISA test in official laboratories, as well as the evaluation of a procedure to increase the sensitivity in samples with low levels of antibodies. This procedure, based on milk protein concentration, allowed us to notably increase the ELISA test's analytical sensitivity, which is useful for milk samples from farms with low within-herd prevalence or pools of bulk tank milk samples. The standardized milk reference material produced here, together with the evaluated procedure to improve analytical sensitivity, could be applied as tools to ensure an accurate diagnosis by official laboratories in bluetongue unvaccinated free areas.

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.

Immunogenicity, Immunological Memory and Monitoring of Disease Activity Following an Anamnestic Immunization With the 13-Valent Pneumococcal Conjugate Vaccine in Children With Idiopathic Nephrotic Syndrome.

Anamnestic 13-valent pneumococcal conjugate vaccine immunization did not affect the relapse risk in pediatric idiopathic nephrotic syndrome. Pneumococcal serotype (PS)-specific antibody titers increased significantly in all groups. Children receiving immunomodulatory treatments (IMTs) displayed significantly lower levels of PS-specific antibodies for 3/8 serotypes tested. PS-specific B-cell counts significantly increased only in healthy controls and patients receiving corticosteroids.

Antibody responses to respiratory syncytial virus: a population-based cross-sectional serological study in Southern China, 2021

ObjectivesWith remarkable progress in the field of respiratory syncytial virus (RSV) prophylaxis, it is critical to understand population immunity against RSV. We aim to describe the RSV pre-F IgG antibodies across all age groups in Southern China and to evaluate the risk factors associated with lower antibody levels. MethodsWe performed a community-based cross-sectional sero-epidemiological study in Anhua County, Hunan Province, Southern China, from July 15, 2021, to November 5, 2021. Serum samples were tested for IgG antibodies against the RSV prefusion F (pre-F) protein using an enzyme-linked immunosorbent assay. We estimated the geometric mean titres (GMTs) and seropositivity rates across all age groups. The generalized linear models were built to identify factors associated with antibody levels. ResultsA total of 890 participants aged 4 months to older than 89 years were enrolled. The lowest RSV pre-F IgG GMTs were observed in infants and toddlers aged 4 months to younger than 2 years (3.0; 95% CI, 2.6–3.5). With increasing age, the RSV pre-F IgG GMT increased to 4.3 (95% CI, 4.1–4.4) between the ages of 2 and younger than 5 years and then stabilized at high levels throughout life. All the children had serological evidence of RSV infection by the age of 5 years. Age was associated with RSV pre-F antibody levels in children, with an estimated 1.9-fold (95% CI, 0.8–3.6) increase in titre per year before 5 years of age, although it was not significantly associated with antibody levels in adults aged older than 60 years. DiscussionOur findings could provide a comprehensive understanding of the gaps in RSV immunity at the population level and inform the prioritization of immunization platforms.

The use of anti-transglutaminase and anti-gliadin antibodies to compare the effect of gluten active and gluten-free diet patients suffering from celiac disease in child and adult

Celiac disease is an autoimmune disorder triggered by the ingestion of gluten in genetically susceptible individuals. The current study aimed to compare the levels of these antibodies in celiac disease patients on active gluten-containing diets and those on gluten-free diets to demonstrate the ability to get rid of Celiac Disease by Gluten-Free Diet. The study involved 100 participants, divided into 60 CD patients and 40 controls, where all participant match in age and gender. The patient group was further divided into two subgroups 40 active celiac and 20 GFD. Blood samples were obtained from all participants, and levels of anti-tTG and anti-gliadin antibodies were using Enzyme-Linked Immunosorbent Assay (ELISA) technology. The results showed The F test indicated a significant difference in the levels of anti-tTG and anti-gliadin antibodies between the active group (G1) and the diet group (G2) in comparison to the control group (G3), with a p-value less than 0.001. Upon conducting a deeper analysis using the least significant difference (LSD) on on anti-tTG IgA and IgG indicate that there are no significant differences between the patient groups G1 and G2, as evidenced by p-values of 0.120 for IgA. However, a significant difference was observed between G1 and G2 for IgG, with a p-value of 0.018. When comparing G1 with G3, and G2 with G3, significant differences were observed, with p-values less than 0.001. In the case of anti-gliadin IgA and IgG, the LSD test revealed a highly significant difference between G1 and G2, as indicated by a p-value less than 0.001. However, no significant differences were found between G1 and G3, with p-values of 0.499 for IgA and 0.110 for IgG. A highly significant difference was none the less observed between G2 and G3, with a p-value less than 0.001.In conclusion, This study highlights the importance of dietary adherence in celiac disease management. Patients on gluten-free diets had significantly lower levels of anti-TG and anti-gliadin antibodies, indicating better control of the autoimmune response. Monitoring these antibody levels can be a valuable tool in assessing the effectiveness of dietary interventions in celiac disease patients.

Intranasal Vaccination with a Respiratory-Syncytial-Virus-Based Virus-like Particle Displaying the G Protein Conserved Region Induces Severe Weight Loss and Pathology upon Challenge with Wildtype Respiratory Syncytial Virus.

Respiratory syncytial virus (RSV) is a major cause of severe respiratory tract disease worldwide, and a pediatric vaccine is not available. We generated a filamentous RSV-based virus-like particle (VLP) that presents the central conserved region of the attachment protein G. This was achieved by co-expressing the matrix protein, phosphoprotein, nucleoprotein, and a hybrid fusion protein in which the F ectodomain was replaced with the G central region (GCR). The latter is relatively conserved and contains a receptor binding site and hence is a logical vaccine target. The immunogenicity and efficacy of the resulting VLP, termed VLP-GCR, were examined in mice using intranasal application without adjuvant. VLP-GCR induced substantial anti-N antibody levels but very low anti-G antibody levels, even after three vaccinations. In contrast, a VLP presenting prefusion-stabilized fusion (preF) protein instead of GCR induced both high anti-F and anti-nucleoprotein antibody levels, suggesting that our GCR antigen was poorly immunogenic. Challenge of VLP-GCR-vaccinated mice caused increased weight loss and lung pathology, and both VLPs induced mucus in the lungs. Thus, neither VLP is suitable as a vaccine for RSV-naive individuals. However, VLP-preF enhanced the proportion of preF antibodies and could serve as a multi-antigen mucosal booster vaccine in the RSV-experienced population.

Original COVID-19 priming regimen impacts the immunogenicity of bivalent BA.1 and BA.5 boosters.

Waning antibody responses after COVID-19 vaccination combined with the emergence of the SARS-CoV-2 Omicron lineage led to reduced vaccine effectiveness. As a countermeasure, bivalent mRNA-based booster vaccines encoding the ancestral spike protein in combination with that of Omicron BA.1 or BA.5 were introduced. Since then, different BA.2-descendent lineages have become dominant, such as XBB.1.5, JN.1, or EG.5.1. Here, we report post-hoc analyses of data from the SWITCH-ON study, assessing how different COVID-19 priming regimens affect the immunogenicity of bivalent booster vaccinations and breakthrough infections (NCT05471440). BA.1 and BA.5 bivalent vaccines boosted neutralizing antibodies and T-cells up to 3 months after boost; however, cross-neutralization of XBB.1.5 was poor. Interestingly, different combinations of prime-boost regimens induced divergent responses: participants primed with Ad26.COV2.S developed lower binding antibody levels after bivalent boost while neutralization and T-cell responses were similar to mRNA-based primed participants. In contrast, the breadth of neutralization was higher in mRNA-primed and bivalent BA.5 boosted participants. Combined, our data further support the current use of monovalent vaccines based on circulating strains when vaccinating risk groups, as recently recommended by the WHO. We emphasize the importance of the continuous assessment of immune responses targeting circulating variants to guide future COVID-19 vaccination policies.