Protein Antibody Levels Research Articles

Exploring the Relationship Between Humoral and Cellular T Cell Responses Against SARS-CoV-2 in Exposed Individuals From Emilia Romagna Region and COVID-19 Severity.

COVID-19 remains a significant global health problem with uncertain long-term consequences for convalescents. We investigated the relationships between anti-N protein antibody levels, severe acute respiratory syndrome (SARS)-CoV-2-associated TCR repertoire parameters, HLA type and epidemiological information from three cohorts of 524 SARS-CoV-2-infected subjects subgrouped in acute phase, seronegative and seropositive convalescents from the Emilia Romagna region. Epidemiological information and anti-N antibody index were associated with TCR repertoire data. HLA type was inferred from TCR repertoire using the HLA3 tool and its association with clonal breadth (CB) and clonal depth (CD) was assessed. Age above 58 years, male and COVID-19 hospitalisation were significantly and independently associated with seropositivity (p = 0.004; p = 0.004; p = 0.04), suggesting an association between high antibody titres and symptoms' severity. As for the TCR repertoire analysis, we found no difference in CB among the cohorts, while CD was higher in seronegative than acute (p = 0.04). However, clustering analysis supported that seronegative patients are endowed with broader CB and deeper CD indicating a compensatory mechanism without effective seroconversion. The CD calculated on the TCRs associated with the single SARS-CoV-2 ORFs in convalescents is higher when compared to the acute. Lastly, we identified and reported on novel HLAs significantly associated with increased risk of hospitalisation such as HLA-C*07:02 carriers (OR = 3.9, CI = 1.1-13.4, p = 0.03) and on HLAs that associate significantly with lower or higher TCR repertoire parameters in a population exposed for the first time to SARS-CoV-2.

Natural Boosting and the Immunogenicity of the XBB.1.5 Monovalent Vaccine in the Coronavirus Disease 2019 Endemic Era: A Longitudinal Observational Study.

With the transition from the coronavirus disease 2019 (COVID-19) pandemic into endemicity, changes in group immunity and the effect of updated XBB.1.5 monovalent vaccine (MonoV) need to be investigated. A multicenter vaccine cohort was followed for 3 years, and the investigation period was classified into the pre-Omicron, Omicron, and endemic eras. Thirteen sampling points were assessed, including pre- and post-MonoV administration. Specimens were classified as vaccinated, molecularly or serologically diagnosed breakthrough infection (BI), natural boosting (NB), or waned. A total of 327 healthcare workers contributed 2645 blood samples from March 2021 to December 2023. The log10 anti-spike protein antibody (SAb) levels, elevated by vaccination, declined linearly in the pre-Omicron era, were maintained during the Omicron era due to BIs, and increased in the endemic era (slope = 0.02, P = .02) without additional vaccination. NB cases increased significantly across the epidemiologic eras. The incidence rate ratios were 2.72 (P < .001) for Omicron/pre-Omicron and 3.39 (P < .001) for endemic/Omicron. Plaque reduction neutralization test (PRNT) titers against circulating strains (XBB.1.5 and XBB.1.9.1) in the NB group maintained previous levels, but ratios to wild-type PRNT and fold changes exhibited significantly enhanced activity. The XBB.1.5 MonoV increased PRNT by 5.8-fold against XBB.1.5 and 6.6-fold against JN.1, showing stronger enhancement against subsequent epidemic strains than the bivalent vaccine. Group immunity in the COVID-19 endemic era exhibited maintained SAb levels and adjusted neutralizing activities through BI and NB. The XBB.1.5 MonoV significantly enhanced neutralizing activity against the vaccine strain and robust immunity against the subsequent epidemic JN.1 strain.

Helicobacter pylori upregulates PAD4 expression via stabilising HIF-1α to exacerbate rheumatoid arthritis

ObjectiveHelicobacter pylori infection has been reported to aggravate rheumatoid arthritis (RA), but the relevant mechanism remains unclear. This study aimed to investigate the underlying pathogenic mechanism of H. pylori infection...

Causal associations between Helicobacter Pylori infection and the risk and symptoms of Parkinson's disease: a Mendelian randomization study.

Increasing evidence suggests an association between Helicobacter pylori (HP) infection and Parkinson's disease (PD) and its clinical manifestations, but the causal relationship remain largely unknown. To investigate the causal relationship between HP infection and PD risk, PD symptoms, and secondary parkinsonism, we conducted two-sample Mendelian randomization (MR). We obtained summary data from genome-wide association studies for seven different antibodies specific to HP proteins and five PD-related phenotypes. The inverse-variance weighted (IVW), weighted median, weighted mode, and MR-Egger methods were used to assess the causal relationships. Sensitivity analyses were performed to examine the stability of the MR results and reverse MR analysis was conducted to evaluate the presence of reverse causality. Genetically predicted HP antibodies were not causally associated with an increased risk of PD. However, HP cytotoxin-associated gene-A (CagA) and outer membrane protein (OMP) antibody level were causally associated with PD motor subtype (tremor to postural instability/gait difficulty score ratio; β = -0.16 and 0.46, P = 0.002 and 0.048, respectively). HP vacuolating cytotoxin-A (VacA) antibody level was causally associated with an increased risk of PD dementia [odds ratio (OR) = 1.93, P = 0.040]. Additionally, HP OMP antibody level was identified as a risk factor for drug-induced secondary parkinsonism (OR = 2.08, P = 0.033). These results were stable, showed no evidence of heterogeneity or directional pleiotropy, and no evidence of a reverse causal relationship. Our findings indicate that HP infection does not increase the risk of PD, but contributes to PD motor and cognitive symptoms. Different types of HP antibodies affect different symptoms of PD. Eradication of HP infection may help modulate and improve symptoms in PD patients.

Joint Damage and Low Lean Body Mass in a Cohort of Peruvian Patients With Rheumatoid Arthritis.

To determine the association between radiologic joint damage (JD) and a lower lean body mass (LBM) in rheumatoid arthritis (RA) patients. A cross-sectional study from a single center established RA cohort. JD and appendicular LBM (arms and legs) were measured with the Sharp/van der Heijde (SvdH) score and dual x-ray absorptiometry expressed as kg/m 2 , respectively. A univariable analysis was used to determine the association between JD an LBM; then, a multivariable regression model was performed to evaluate the persistence of this association, adjusted by age, gender, disease duration, socioeconomic status (by the Graffar method), tobacco use, anticitrullinated protein antibody levels, Disease Activity Score in 28 joints for RA with erythrocyte sedimentation rate, glucocorticoid use (as prednisone equivalent), disease-modifying antirheumatic drug use, body mass index, and disability (by the multidimensional Health Assessment Questionnaire). Two hundred forty-seven patients were included; the average (SD) age was 63.0 (12.8) years, disease duration 20 (15.00) years, the total SvdH was 66 (86.75), and the aLBM was 13.6 (3.82) kg/m 2 . In the univariable analysis, a lower appendicular LBM was associated with higher SvdH score on the female population, in terms of the total ( B = -8.6, p < 0.01), bone erosion (-4.4, p < 0.01), and joint space narrowing (-4.2, p < 0.01) scores; this correlation remained in the multivariable analysis in terms of total SvdH ( B = -9.5, p < 0.01), bone erosion (-5.2, p < 0.01), and joint space narrowing (-4.3, p < 0.01). A lower LBM in female patients was associated with more severe JD independently of other variables examined. Strategies aimed at preserving LBM could have a favorable impact on the course of disease.

Elucidating the Immune Response to SARS-CoV-2: Natural Infection versus Covaxin/Covishield Vaccination in a South Indian Population.

A natural infection or a vaccination can initially prime the immune system to form immunological memory. The immunity engendered by vaccination against COVID-19 versus natural infection with SARS-CoV-2 has not been well studied in the Indian population. In this study, we compared the immunity conferred by COVID-19 vaccines to naturally acquired immunity to SARS-CoV-2 in a South Indian population. We examined binding and neutralizing antibody (NAb) levels against the ancestral and variant lineages and assessed the ex vivo cellular parameters of memory T cells, memory B cells, and monocytes and finally measured the circulating cytokine response. COVID-19 vaccination stimulates heightened levels of IgG antibodies against the original strain of SARS-CoV-2, as well as increased binding to the spike protein and neutralizing antibody levels. This enhanced response extends to variant lineages such as B.1.617.2 (Delta, India), B.1.1.529 (Omicron, India), B.1.351 (Beta, South Africa), and B.1.1.7 (Alpha, UK). COVID-19 vaccination differs from SARS-CoV-2 infection by having increased frequencies of classical memory B cells, activated memory B and plasma cells, CD4/CD8 T cells of effector memory, effector cells, stem cell-like memory T cells, and classical and intermediate monocytes and diminished frequencies of CD4/CD8 T cells of central memory and non-classical monocytes in vaccinated individuals in comparison to those with natural infection. Thus, COVID-19 vaccination is characterized by enhanced humoral responses and robust activation of innate and memory T cell responses in comparison to natural infection in a South Indian population.

Characteristics of Lung Cancer Patients With Asymptomatic or Undiagnosed SARS-CoV-2 Infections

IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be spread by individuals unaware they are infected. Such dissemination has heightened ramifications in cancer patients, who may need to visit healthcare facilities frequently, be exposed to immune-compromising therapies, and face greater morbidity from coronavirus disease 2019 (COVID-19). We determined characteristics of (1) asymptomatic, clinically diagnosed, and (2) serologically documented but clinically undiagnosed SARS-CoV-2 infection among individuals with lung cancer. Patients and methodsIn a multicenter registry, individuals with lung cancer (regardless of prior SARS-CoV-2 vaccination or documented infection) underwent collection of clinical data and serial blood samples, which were tested for antinucleocapsid protein antibody (anti-N Ab) or IgG (N) levels. We used multivariable logistic regression models to investigate clinical characteristics associated with the presence or absence of symptoms and the presence or absence of a clinical diagnosis among patients with their first SARS-CoV-2 infection. ResultsAmong patients with serologic evidence or clinically documented SARS-CoV-2 infection, 80/142 (56%) had no reported symptoms at their first infection, and 61/149 (40%) were never diagnosed. Asymptomatic infection was more common among older individuals and earlier-stage lung cancer. In multivariable analysis, non-white individuals with SARS-CoV-2 serologic positivity were 70% less likely ever to be clinically diagnosed (P = .002). ConclusionsIn a multicenter lung cancer population, a substantial proportion of SARS-CoV-2 infections had no associated symptoms or were never clinically diagnosed. Because such cases appear to occur more frequently in populations that may face greater COVID-19-associated morbidity, measures to limit disease spread and severity remain critical.

Addressing dispersion in mis-measured multivariate binomial outcomes: A novel statistical approach for detecting differentially methylated regions in bisulfite sequencing data.

Motivated by a DNA methylation application, this article addresses the problem of fitting and inferring a multivariate binomial regression model for outcomes that are contaminated by errors and exhibit extra-parametric variations, also known as dispersion. While dispersion in univariate binomial regression has been extensively studied, addressing dispersion in the context of multivariate outcomes remains a complex and relatively unexplored task. The complexity arises from a noteworthy data characteristic observed in our motivating dataset: non-constant yet correlated dispersion across outcomes. To address this challenge and account for possible measurement error, we propose a novel hierarchical quasi-binomial varying coefficient mixed model, which enables flexible dispersion patterns through a combination of additive and multiplicative dispersion components. To maximize the Laplace-approximated quasi-likelihood of our model, we further develop a specialized two-stage expectation-maximization (EM) algorithm, where a plug-in estimate for the multiplicative scale parameter enhances the speed and stability of the EM iterations. Simulations demonstrated that our approach yields accurate inference for smooth covariate effects and exhibits excellent power in detecting non-zero effects. Additionally, we applied our proposed method to investigate the association between DNA methylation, measured across the genome through targeted custom capture sequencing of whole blood, and levels of anti-citrullinated protein antibodies (ACPA), a preclinical marker for rheumatoid arthritis (RA) risk. Our analysis revealed 23 significant genes that potentially contribute to ACPA-related differential methylation, highlighting the relevance of cell signaling and collagen metabolism in RA. We implemented our method in the R Bioconductor package called "SOMNiBUS."

Integrated microbiome and metabolome analysis reveals that new insight into Radix pseudostellariae polysaccharide enhances PRRSV inactivated vaccine.

In this study, we investigated how Radix pseudostellariae polysaccharide (RPP) enhances the immune response of the inactivated porcine reproductive and respiratory syndrome virus (PRRSV) vaccine through interactions with the microbiome and metabolome. We pretreated sows with 10 mg/kg body weight of RPP via drinking water for 7 days prior to intramuscular injection of the PRRSV vaccine. This significantly increased the concentrations of PRRSV GP5 protein antibody, interleukin (IL)-2, IL-4, IL-10, and interferon (IFN)-γ. Oral administration of RPP also significantly improved the abundance of beneficial bacteria in the stool, such as Parabacteroides distasonis, Prevotella_copri, Eubacterium_sp., and Clostridium_sp._CAG:226, and decreased the levels of potentially pathogenic bacteria, such as Paraeggerthella and [Clostridium] innocuum, compared to the vaccine alone. These bacterial changes were confirmed using quantitative real-time polymerase chain reaction (Q-PCR). Moreover, RPP treatment significantly increased the blood concentrations of L-theanine, taurodeoxycholic acid (TDCA), and N-arachidonoyl proline, and decreased the levels of L-glutamine, oclacitinib, lipoxin C4, and leukotriene C5 in sows after immunization (p< 0.05). The concentrations of various blood metabolites were validated using sandwich enzyme-linked immunosorbent assay (ELISA), confirming the accuracy of the metabolomics data. Intriguingly, the integration of microbiome and metabolome analyses highlighted the significance of Prevotella_copri and TDCA. We consequently developed a mouse immunity model using GP5 protein and discovered that oral administration of RPP significantly enhanced the levels of GP5 protein antibodies, IL-2, IL-4, IL-10, and IFN-γ in mouse serum. It also increased the number of CD3+ and CD3+CD4+ cells in the spleen. Additionally, Prevotella_copri was administered into the large intestine via the anus for 7 days prior to the intramuscular injection of the PRRSV GP5 protein. The results demonstrated a significant increase in TDCA and GP5 antibody concentration in the mouse serum, indicating that RPP modulates Prevotella_copri to elevate its metabolite TDCA, thereby enhancing the GP5 antibody level. In conclusion, oral administration of 10 mg/kg RPP optimizes gut flora diversity and blood metabolites, particularly Prevotella_copri and TDCA, thereby improving the immune response to the inactivated PRRSV vaccine.

Longitudinal dynamic single-cell mass cytometry analysis of peripheral blood mononuclear cells in COVID-19 patients within 6 months after viral RNA clearance

This study investigates the longitudinal dynamic changes in immune cells in COVID-19 patients over an extended period after recovery, as well as the interplay between immune cells and antibodies. Leveraging single-cell mass spectrometry, we selected six COVID-19 patients and four healthy controls, dissecting the evolving landscape within six months post-viral RNA clearance, alongside the levels of anti-spike protein antibodies. The T cell immunophenotype ascertained via single-cell mass spectrometry underwent validation through flow cytometry in 37 samples. Our findings illuminate that CD8 + T cells, gamma-delta (gd) T cells, and NK cells witnessed an increase, in contrast to the reduction observed in monocytes, B cells, and double-negative T (DNT) cells over time. The proportion of monocytes remained significantly elevated in COVID-19 patients compared to controls even after six-month. Subpopulation-wise, an upsurge manifested within various T effector memory subsets, CD45RA + T effector memory, gdT, and NK cells, whereas declines marked the populations of DNT, naive and memory B cells, and classical as well as non-classical monocytes. Noteworthy associations surfaced between DNT, gdT, CD4 + T, NK cells, and the anti-S antibody titer. This study reveals the changes in peripheral blood mononuclear cells of COVID-19 patients within 6 months after viral RNA clearance and sheds light on the interactions between immune cells and antibodies. The findings from this research contribute to a better understanding of immune transformations during the recovery from COVID-19 and offer guidance for protective measures against reinfection in the context of viral variants.

Impact of Circulating Anti-Spike Protein Antibody Levels on Multi-Organ Long COVID Symptoms.

Patients with long COVID syndrome present with various symptoms affecting multiple organs. Vaccination before or after SARS-CoV-2 infection appears to reduce the incidence of long COVID or at least limit symptom deterioration. However, the impact of vaccination on the severity and extent of multi-organ long COVID symptoms and the relationship between the circulating anti-spike protein antibody levels and the severity and extent of multi-organ symptoms are unclear. This prospective cohort study included 198 patients with previous PCR-verified SARS-CoV-2 infection who met the criteria for long COVID syndrome. Patients were divided into vaccinated (n = 138, 69.7%) or unvaccinated (n = 60, 30.3%) groups. Anti-spike protein antibody levels were determined at initial clinical presentation and compared between the groups. Long COVID symptoms were quantified on the basis of the number of affected organs: Class I (mild) with symptoms in three organs, Class II (moderate) with symptoms in four to five organs, and Class III (severe) with symptoms in six or more organ systems. Associations between time to infection and vaccination with anti-spike protein antibody levels were assessed. The anti-spike protein antibody levels were 1925 ± 938 vs. 481 ± 768 BAU/mL (p < 0.001) in the vaccinated vs. unvaccinated patients. The circulating anti-spike antibody cutoff of 665.5 BAU/mL allowed us to differentiate the vaccinated from the unvaccinated patients. Vaccinated patients had fewer class II and class III multi-organ symptoms (Class II 39.9% vs. 45.0%; Class III 10.1% vs. 23.3%, p-value 0.014). Anti-spike antibody level correlated negatively with multi-organ symptom classes (p = 0.016; 95% CI -1.229 to -0.126). Anti-spike antibody levels in unvaccinated patients declined markedly with time, in contrast to the persistence of high anti-spike antibody levels in the vaccinated patients. Multi-organ symptoms were lower in vaccinated long-COVID patients, especially in those with higher anti-spike antibody levels (≥665.5 BAU/mL). Classifying the symptoms on the basis of the number of affected organs enables a more objective symptom quantification.

Racial Differences in Plasma Microbial Translocation and Plasma Microbiome, Implications in Systemic Lupus Erythematosus Disease Pathogenesis.

Black groups have increased prevalence and accelerated pathogenicity of systemic lupus erythematosus (SLE) compared to other ethnic/racial groups. The microbiome and systemic microbial translocation are considered contributing factors to SLE disease pathogenesis. However, racial differences in the plasma microbiome and microbial translocation in lupus remain unknown. In the current study, we investigated plasma levels of microbial translocation (lipopolysaccharide [LPS] and zonulin) and the plasma microbiome using microbial 16S RNA sequencing of Black and White patients with SLE and Black and White healthy controls. Plasma microbial translocation was increased in Black patients versus in White patients and in patients with SLE versus healthy controls regardless of race. Compared to sex, age, and disease status, race had the strongest association with plasma microbiome differences. Black groups (Black controls and Black patients) had lower α-diversity than White groups (White controls and White patients) and more distinct β-diversity. Black and White patients demonstrated differences in plasma bacterial presence, including Staphylococcus and Burkholderia. Compared to White patients, Black patients had higher SLE Disease Activity Index (SLEDAI) scores and urinary protein levels as well as a trend for increased anti-double-stranded DNA (dsDNA) antibody levels consistent with the known increased severity of lupus in Black patients overall. Certain plasma bacteria at the genus level were identified that were associated with the SLEDAI score, urinary protein, and anti-dsDNA antibody levels. This study reveals racial differences in both quality and quantity of plasma microbial translocation and identified specific plasma microbiome differences associated with SLE disease pathogenesis. Thus, this study may provide new insights into future potential microbiome therapies on SLE pathogenesis.

Evaluation of Antibody Response After COVID-19 Vaccination in Healthcare Workers: A Turkish Tertiary Hospital Experience

Objective: It was aimed to explore the correlation between demographic characteristics and the presence of comorbidity in the antibody response after the second dose of vaccination in healthcare workers in this study. In addition, the third and fourth dose approaches of the participants and the protection of the antibody levels formed by the two doses of vaccine against COVID-19 were examined observationally.&#x0D; Materials and Methods: Health workers, whose NCP and S protein antibody levels were detected on the 30th day after the second dose of the CoronaVac vaccine, were followed up in terms of being vaccinated for the third and fourth doses and having COVID-19.&#x0D; Results: Higher levels of S antibodies were detected in women after two doses of vaccination (p=0.001). It was pointed out that smoking has a negative effect on the antibody response after vaccination (p=0.008). People who had pre-vaccine COVID-19 had higher NCP antibody levels after two doses of vaccination (p=0.013). Of the participants, 152 (97.4%) were vaccinated with the third dose and 110 (70.5%) with the fourth dose.&#x0D; Conclusion: The antibody response after two doses of inactivated CoronaVac® vaccination probe is significantly higher in women, younger people, non-smokers, and people who have not been previously infected with the SARS-CoV-2.

Humoral and cellular immune responses against SARS-CoV-2 post-vaccination in immunocompetent and immunocompromised cancer populations.

The study was prompted by a desire to better assess the immune status of patients among our cancer host cohort, one of the largest in the New York metropolitan region. Hackensack Meridian Health is the largest healthcare system in New Jersey and cared for more than 75,000 coronavirus disease 2019 patients in its hospitals. The John Theurer Cancer Center sees more than 35,000 new cancer patients a year and performs more than 500 hematopoietic stem cell transplants. As a result, the work was undertaken to assess the effectiveness of vaccination in inducing humoral and cellular responses within this demographic.

Impact of Antenatal SARS-CoV-2 Exposure on SARS-CoV-2 Neutralization Potency.

A pregnancy booster dose significantly reduces the risk and severity of COVID-19, and it is widely recommended. A prospective cohort study was conducted to compare the transplacental passage of maternal antibodies from vaccination or infection during three trimesters against both the vaccine-targeted Wuhan strain and the Omicron strain of SARS-CoV-2. Maternal-infant dyads from vaccinated mothers were collected between 6 June 2022 and 20 September 2022. We analyzed 38 maternal-infant dyads from mothers who had been infected with COVID-19 and 37 from mothers without any previous infection. Pregnant women who received their last COVID-19 vaccine dose in the third trimester exhibited the highest anti-spike protein antibody levels and neutralizing potency against both the Wuhan strain and Omicron BA.2 variant in their maternal and cord plasma. Both second- and third-trimester vaccination could lead to a higher level of neutralization against the Wuhan and Omicron strains. COVID-19 infection had a negative effect on the transplacental transfer ratio of SARS-CoV-2 antibodies. A booster dose during the second or third trimester is encouraged for the maximum transplacental transfer of humoral protection against COVID-19 for infants.

P1080 Real-world Study on Early Predictors of Infliximab Treatment Efficacy in Crohn's disease

Abstract Background Infliximab (IFX) can effectively induce and maintain the clinical remission of Crohn's disease (CD). However, a substantial number of CD patients experience primary or secondary nonresponse to IFX during treatment. Therefore, it is essential to identify early predictors of IFX treatment efficacy. Methods This study included 147 CD patients. Based on clinical outcomes, patients were categorized into IFX nonresponse and response group. We collected and compared laboratory data on blood routine examination, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fecal calprotectin and post-induction IFX drug concentration and antibody levels in both groups. Logistic regression models were employed to identify potential factors associated with the risk of IFX nonresponse. Machine learning using random forest analysis was utilized to quantitatively assess the predictive features for IFX treatment efficacy and ROC curves was used to evaluate the model’s accuracy. Additionally, we performed HE staining and double immunofluorescence staining for CD64 and CD206 on intestinal biopsy tissues obtained before IFX treatment to compare the difference of macrophage subtypes between the nonresponse and response groups. Results Data from both cohorts revealed that patients in the IFX nonresponse group had lower drug concentration (P &amp;lt; 0.001), higher antibody levels (P &amp;lt; 0.001), and increasing ESR during the induction therapy (P &amp;lt; 0.001). Univariate and multivariate Logistic regression models demonstrated that IFX drug concentration and the ratio of ESR before and after induction therapy were associated with the risk of nonresponse. After the induction period, for each unit increase in drug concentration (1 μg/ml), the risk of IFX nonresponse decreased by 23% (RR= 0.77, 95% CI = 0.68-0.89), while each doubling of the ESR ratio after induction was associated with a 1.43-fold increase in the risk of nonresponse (RR= 2.43, 95% CI = 1.48-4.00). After combining data from the two cohorts, random forest machine learning analysis revealed that drug concentration below 1.5 μg/ml and an increase in ESR during induction could predict IFX nonresponse, with ROC curve areas of 0.740 and 0.651, respectively. Furthermore, immunofluorescence staining of intestinal mucosal biopsy tissues before IFX treatment showed a higher proportion of M1-type macrophages in the nonresponse group compared to the response group (P &amp;lt; 0.05). Conclusion Our study suggests that lower post-induction IFX drug concentrations and an increase in ESR during the induction phase are predictive of IFX nonresponse. Additionally, a higher proportion of M1-type macrophages in the intestinal mucosa before IFX treatment is associated with IFX nonresponse.

Protective effects of a novel chimeric virus–like particle vaccine against virulent NDV and IBDV challenge

Newcastle disease (ND) and infectious bursal disease (IBD) pose significant threats to the chicken industry, causing substantial economic losses. Currently, immunization through vaccination is the most effective strategy to prevent ND and IBD but currently used traditional vaccines, including inactivated or attenuated vaccines, face challenges in achieving a balance between immunogenicity and safety. To develop a green and efficient novel vaccine for ND and IBD, we developed a bivalent chimeric virus-like particle vaccine (ND-IBD cVLPs) displaying the ND virus (NDV) HN protein and the IBD virus (IBDV) VP2 protein based on the ND VLPs carrier platform and insect baculovirus expression system. This study aimed to evaluate the immunogenicity and protective efficacy of ND-IBD cVLPs in specific pathogen-free chickens. Chickens were immunized with 50 µg of purified ND-IBD cVLPs at 7 days old, boosted at 21 days old, and challenged at 42 days old. The results demonstrated that ND-IBD cVLPs stimulated highly effective hemagglutination inhibition antibody levels against NDV HN protein and enzyme-linked immunosorbent assay antibody levels against the IBDV VP2 protein. Furthermore, ND-IBD cVLPs provided complete protection against virulent NDV and IBDV challenges and mitigated pathological damage to the lung caused by NDV infection and the bursa of Fabricius caused by IBDV infection. These findings suggest that ND-IBD cVLPs hold promise as a safe and efficient novel vaccine candidate for the effective prevention of ND and IBD, extending the development of a foreign protein delivery platform of ND VLPs.

Post-acute sequelae of COVID-19 and longitudinal antibody levels in a community-based cohort.

Coronavirus disease 2019 (COVID-19) infection invokes variable immune responses and poses a risk of post-acute sequelae SARS-CoV-2 infection (PASC) symptoms; however, most data on natural history are derived from patients with severe infection. Further data are needed among patients with mild infection, who comprise most cases. The Dallas Fort-Worth (DFW) COVID-19 Prevalence Study included 21,597 community-dwelling adults (ages 18-89) who underwent COVID-19 PCR and anti-nucleocapsid antibody testing between July 2020 and March 2021. We invited participants with positive COVID-19 results (cases) and a subset with negative results (controls), matched on age, sex, race/ethnicity, and ZIP code, to complete a follow-up questionnaire for PASC symptoms and repeat anti-nucleocapsid testing, and anti-spike antibody testing between July and December 2021. Of 3,917 adults invited to participate, 2260 (57.7%) completed the questionnaire- 1150 cases and 1110 controls. Persistent symptoms were reported in 21.1% of cases, with the most common being shortness of breath, fatigue, and loss of taste or smell. Among 292 cases with asymptomatic infection, >15% reported new fatigue and 8-10% reported new loss of taste/smell, myalgias, or headache. Median anti-nucleocapsid levels in cases decreased from 3.5U to 0.7U over a median follow-up of 8.6 months. Anti-spike antibody levels at 6-7 months post-vaccination in cases were similar to that of controls. More than 1 in 5 patients with COVID-19 infection, including those with mild infection, reported persistent symptoms during follow-up. Both nucleocapsid and spike protein antibody levels decreased within six months following a COVID-19 infection and vaccination.

Immunization of children with inflammatory bowel disease against SARS-CoV-19 infection: A prospective single centre cohort study

BackgroundReal-world data of children with inflammatory bowel disease (IBD) after SARS-CoV-2 vaccination are needed. MethodThis prospective, observational study evaluate antibody kinetics of children with IBD 6 months after immunization with COVID-19 mRNA vaccine. Results24 children with IBD were included, 22 received immunosuppressive treatment. After five weeks the spike protein antibody level was positive in 95% of the cases. After six months all participants had seropositivity results, though the titre was decreasing. ConclusionThese data show the effectiveness of SARS-CoV2 immunization and the antibody decay over time, that highlight the importance of booster vaccines.

Immunocompetent and immunocompromised cancer populations: Post-vaccination humoral and cellular immune responses against SARS-CoV-2.

e18779 Background: Cancer patients are at risk for severe COVID-19 outcomes due to an impaired immune response amongst other factors. However, the immunogenicity of SARS-CoV-2 vaccination is poorly characterized in this population. We hypothesized that cancer versus non-cancer individuals would mount less robust humoral and/or cellular immune SARS-CoV-2 responses. Methods: Among 594 vaccinated individuals with varying COVID-19 statuses (ie, not known to have been infected, previously infected, or with Long COVID), receptor binding domain (RBD) and total spike protein antibody levels, as well as T cell responses were assessed in non-cancer healthy individuals (n=479), non-cancer immunocompromised individuals (n=35), and cancer patients with hematologic malignancies or carcinomas (n=80). Among cancer patients, 85% (n=68) had an underlying hematologic malignancy with 62% (n=42) receiving B-cell depleting treatments at one point pre-blood collection and 43% (n=18) ≤30 days pre-blood collection. RBD antibody responses were measured using the HMH-CDI RUO SARS-CoV-2 RBD ELISA Assay. CD4+ and CD8+ T cell reactivity was measured with the QuantiFERON SARS-CoV-2 RUO Starter and Extended Pack Test. Results: 98% (n=469) of non-cancer and 76% (n=61) of cancer individuals had RBD antibody titers &gt;999 U/mL, and of these, 60% (n=282) non-cancer and 43% (n=26) cancer individuals had elevated T cell responses - indicating most vaccinated individuals mounted robust cellular and/or humoral responses. Robust antibody and elevated T cell responses strongly correlated in the non-cancer cohort but not in the cancer cohort. Composite T cell responses were higher in individuals previously infected with SARS-CoV-2 or diagnosed with Long-COVID compared to uninfected individuals. A difference ( P&lt;0.001) was found between T cell responses in non-cancer healthy (n=479) and carcinoma (n=12) cohorts but not between non-cancer healthy and hematologic malignancy (n=68) cohorts, with the highest T cell responses observed in the non-cancer healthy cohort followed by the hematologic malignancy cohort, and lastly the carcinoma cohort. Conclusions: No prominent correlation was seen between antibody and T cell levels in the cancer cohort likely due to the effect of B-cell targeted therapies that suppress antibody responses. The study supports a suppressive role of B cell targeted therapies in blood cancer patients on antibody responses, but not on T cell responses to SARS-CoV-2 vaccination. Interestingly, we found T cell responses to have wide variation in the hematologic malignancy cohort, likely reflective of the highly dysregulated T cell phenotype in certain liquid tumors such as CLL patients. SARS-CoV-2 vaccination continues to be an effective way to induce humoral and cellular immune responses, a key preventive measure against infection and/or subsequent more severe adverse outcomes.