Serum IgG Antibody Levels Research Articles

Safety and immunogenicity of NVX-CoV2373 (TAK-019) vaccine in healthy Japanese adults: Interim report of a phase I/II randomized controlled trial

BackgroundWe evaluated the safety and immunogenicity of NVX-CoV2373, a recombinant SARS-CoV-2 nanoparticle vaccine, in healthy Japanese participants. MethodsThis phase 1/2, randomized, observer-blind, placebo-controlled trial conducted in Japan (two sites), enrolled healthy Japanese adults aged ≥ 20 years with no history/risk of SARS-CoV-2 infection and no prior exposure to other approved/investigational SARS-CoV-2 vaccines or treatments. Participants were stratified by age (< 65 or ≥ 65 years) and randomized to receive two doses of either NVX-CoV2373 (5 μg SARS-CoV-2 rS; 50 μg Matrix-M1) or placebo, 21 days apart. Primary outcomes were safety and immunogenicity assessed by serum IgG antibody levels against SARS-CoV-2 rS protein on day 36. Herein, we report the primary data analysis at 4 weeks after the second dose, ahead of 12-month follow-up completion (data cut-off: 8 May 2021). ResultsBetween 12 February 2021 and 17 March 2021, 326 subjects were screened, and 200 participants enrolled and randomized: NVX-CoV2373, n = 150; placebo, n = 50. Solicited adverse events (AEs) through 7 days after each injection occurred in 121/150 (80.7%) and 11/50 (22.0%) participants in the NVX-CoV2373 and placebo arms, respectively. In the NVX-CoV2373 arm, tenderness and injection site pain were the most frequently reported solicited AEs after each vaccination, irrespective of age. Robust immune responses occurred with NVX-CoV2373 (n = 150) by day 36: IgG geometric mean fold rise (95% confidence interval) 259 (219, 306); seroconversion rate 100% (97.6, 100). No such response occurred with placebo (n = 49). ConclusionTwo doses of NVX-CoV2373 given with a 21-day interval demonstrated acceptable safety and induced robust anti-SARS-CoV-2 immune responses in healthy Japanese adults. Funding: Takeda Pharmaceutical Company Limited and Japan Agency for Medical Research and Development (AMED). ClinicalTrials.gov identifier: NCT04712110.

Serological response to SARS-CoV-2 vaccination in patients with inflammatory rheumatic disease treated with disease modifying anti-rheumatic drugs: A cohort study and a meta-analysis

IntroductionVaccination is considered as a cornerstone of the management of COVID-19 pandemic. However, while vaccines provide a robust protection in immunocompetent individuals, the immunogenicity in patients with inflammatory rheumatic diseases (IRD) is not well established.MethodsA monocentric observational study evaluated the immunogenicity of a two-dose regimen vaccine in adult patients with IRD (n = 123) treated with targeted or biological therapies. Serum IgG antibody levels against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins were measured after the second vaccination. In addition, a search for observational studies performed in IRD under biologic or targeted therapies up to September 31, 2021 (PROSPERO registration number: CRD42021259410) was undertaken in publication databases, preprint servers, and grey literature sources. Studies that reported sample size, study date, location, and seroprevalence estimate were included. A meta-analysis was conducted to identify demographic differences in the prevalence of SARS-CoV-2 antibodies.ResultsOf 123 patients (median age 66 IQR 57–75), 69.9% have seroconverted after vaccination. Seroconverted patients were older than non-seroconverted ones in our cohort. Rituximab was associated with a significantly low antibody response. Besides, we identified 20 seroprevalence studies in addition to our cohort including 4423 participants in 11 countries. Meta-analysis confirmed a negative impact of rituximab on seroconversion rate and suggested a less substantial effect of abatacept, leflunomide and methotrexate.ConclusionRituximab impairs serological response to SARS-CoV-2 vaccines in patients with IRD. This work suggests also a negative impact of abatacept, methotrexate or leflunomide especially when associated to biological therapy.

SARS-CoV-2 mRNA Vaccination in People with Multiple Sclerosis Treated with Fingolimod: Protective Humoral Immune Responses May Develop after the Preferred Third Shot.

Evidence suggests limited development of protective IgG responses to mRNA-based vaccines in sphingosine-1-phosphate receptor (S1PR)-modulator treated individuals with multiple sclerosis (MS). We studied the extent of the humoral immune response after the preferred third mRNA SARS-CoV-2 vaccine in S1PR-modulator treated people with MS (pwMS) and insufficient IgG responses after the standard immunization scheme. Eight pwMS that were treated with fingolimod received a third homologous SARS-CoV-2 mRNA vaccine dose, either the Moderna’s mRNA-1273 or Pfizer-BioNTech’s BNT162b2 vaccine. We quantified the serum levels of IgG antibodies against the receptor-binding domain of SARS-CoV-2 four weeks later. An antibody titer of 100 AU/mL or more was considered protective. After the third vaccination, we found clinically relevant IgG titers in four out of eight individuals (50%). We conclude that the humoral immune response may reach protective levels after the third preferred dose of the homologous SARS-CoV-2 mRNA vaccine. Vaccine shots in S1PR-modulator treated pwMS ahead of schedule may be a strategy to overcome insufficient humoral immune responses following the standard vaccination scheme.

Humoral and cellular response to COVID-19 vaccination in patients with autoimmune inflammatory rheumatic diseases under real-life conditions.

ObjectivesSuccessful vaccination is key to overcoming the COVID-19 pandemic. Immunosuppressive medication is known to potentially compromise vaccination responses, and expansion of our knowledge on vaccination efficacy in patients with autoimmune inflammatory rheumatic diseases (AIIRD) is therefore of utmost importance.MethodsWe conducted a single-centre observational study and evaluated the efficacy of approved COVID-19 vaccines in 303 adult AIIRD patients. Serum levels of IgG antibodies against the S1 subunit of SARS-CoV-2 spike proteins (anti-S IgG) were measured at least two weeks after vaccination. In a subgroup of patients without humoral response, T-cell responses were determined using an interferon-γ gamma release assay.ResultsOverall seropositivity rate was 78.5% and was significantly lower in patients under immunosuppressive therapy (75.7 vs 93.2%, P = 0.009). No difference regarding the vaccination type was observed. Glucocorticoids, mycophenolate-mofetil, TNF inhibitors, tocilizumab, abatacept and rituximab were all associated with non-response after proper vaccination. The risk was highest under RTX therapy (OR 0.004, 95% CI 0.001, 0.023, P < 0.0001). A strong negative correlation was observed between time since vaccination with an mRNA vaccine and anti-S antibody levels (r=–0.6149, P < 0.0001). In patients without humoral response, a T-cell response was found in 50%.ConclusionsCOVID-19 vaccination in patients with AIIRD is effective using any approved vaccine. Humoral response might be impaired depending on the individual immunosuppressive medication. The risk of non-response is highest under rituximab therapy. Anti-S IgG antibody levels wane over time after mRNA vaccination. Importantly, 50% of humoral non-responders showed a T-cellular response, suggesting T-cell-mediated protection to a certain extent.

Clinical Evaluation of Serum Levels of SARS-CoV-2 Anti-Spike Protein IgG Antibodies in Infected Patients and Vaccinated Subjects.

The aim was clinical evaluation of immune response against SARS-CoV-2, analyzing serum levels of IgG antibodies against the SARS-CoV-2 protein S in infected and vaccinated patients, as well as in subjects with and without frequent comorbidities (arterial hypertension, diabetes mellitus, heart disease, and chronic respiratory disease). Patients infected by SARS-CoV-2 confirmed by RT-PCR and subjects vaccinated with vaccines based on the mRNA encoding the SARS-CoV-2 protein S were studied. SARS-CoV-2 anti-S IgG serum levels were quantified by chemiluminescent microparticle immunoassay. There were 79 infected patients with a median age of 53.0 years; 35 women and 44 men; 42 patients with any comorbidities and 37 without comorbidities. The median of SARS-CoV-2 anti-S IgG serum level was 203.4 BAU/mL (11.6 - 5,620.6). The median antibody level in the infected patients with any comorbidities was higher than those without comorbidities. The group of vaccinated subjects included 96 subjects with a median age of 49.5 years; 77 women and 19 men; 31 subjects with any comorbidities and 65 without comorbidities. The median of SARS-CoV-2 anti-S IgG serum levels was 1,145.6 BAU/mL (138.3 - 4,828.1). No significant differences were found in terms of specific or global comorbidities in the vaccinated subjects. SARS-CoV-2 anti-S IgG serum levels were 5.6 times higher in vaccinated subjects than infected patients. The vaccination produces higher serum antibody levels than SARS-CoV-2 infection. This reinforces the indication for the vaccine in infected patients. These antibodies did not decrease significantly in patients with frequent comorbidities such as hypertension, diabetes, heart disease or chronic respiratory disease.

Evaluation of neutralizing antibodies after vaccine BNT162b2: Preliminary data.

It is well-known that the Coronavirus Disease 2019, which is caused by the beta-coronavirus severe acute respiratory syndrome (SARS-CoV-2), emerged in December 2019 followed by an outbreak first reported in Wuhan, China. Thus far, vaccination appears to be the only way to bring the pandemic to an end. In the present study, immunogenicity data was evaluated using LIAISON® SARS-CoV-2 TrimericS IgG assay (DiaSorin S.p.A) among a sample of 52 vaccinated healthcare workers, five of whom were previously infected with SARS-CoV-2 and 47 who were seronegative, over a time span of ≤90 days following the second dose of the BNT162b2 mRNA vaccine. The test detects antibodies against the Trimeric complex (S1, S2 and receptor binding domain). The overall mean value of the serum levels of IgG antibodies to SARS-CoV-2 30 days following the second dose of the vaccine was 1,901.8 binding arbitrary unit (BAU)/ml, after 60 days the mean value declined to 1,244.9 BAU/ml. The antibody levels then reached a plateau, as confirmed by the antibody test carried out 90 days following the second dose, which revealed a mean value of 1,032.4 BAU/ml (P<0.0001). A higher level was observed at all three times in male subjects compared with female subjects, and in younger male participants compared with female participants, although these differences did not reach a statistically significant level. Similarly, no significant difference was found in antibody values at different times according to age. After the second dose of the vaccine, two subjects were infected with SARS-CoV-2, and an increase in antibody values in the third assay was observed in both individuals.

Risk factors of impaired humoral response to COVID-19 vaccination in rituximab-treated patients.

ObjectiveTo identify which factors influence humoral response to coronavirus disease 2019 (COVID-19) vaccination in rituximab (RTX)-treated patients.MethodsThis was an observational, prospective, usual care study including consecutive patients with inflammatory rheumatic diseases in maintenance therapy with RTX. All patients received a two-dose regimen COVID-19 vaccination. Serum IgG antibody levels against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins were measured at the time of the new RTX infusion.ResultsFrom the recruited patients, 16/45 (36%) produced antibodies reaching the assay cut-off value of 15 AU/ml and 29/45 (64%) had a negative serology. Within RTX-treated patients, 25 (56%) had undetectable B cells. Negative serology was associated with undetectable B cells (24/25 vs 5/20, P < 0.001). Moreover, SARS-CoV-2 spike antibodies correlated with CD19 counts (r = 0.86, P < 0.001). The effect of RTX and MTX was additive in terms of seroconversion rates (23% vs 50% in patients receiving RTX in monotherapy, P = 0.12) and SARS-CoV-2 spike antibody levels [3.80 (95% CI 3.80, 7.50) vs 75 (95% CI 3.8, 353) AU/ml in patients receiving RTX in monotherapy; P = 0.025]. Multivariate analyses including demographics, disease characteristics, gammaglobulin levels, RTX and other therapies used, CD19 counts, and the time between the last RTX infusion and vaccination identified detectable B cells as the only variable independently associated with seropositivity [odds ratio 35.2 (95% CI 3.59, 344.20)].ConclusionsB cell depletion is the main independent contributing factor of antibody response to SARS-CoV-2 vaccination in RTX-treated patients. Monitoring CD19 may be of interest to identify the most appropriate period to perform vaccination.

Pre-Existing Humoral Immunological Memory Is Retained in Patients with Multiple Sclerosis Receiving Cladribine Therapy.

Cladribine (CLAD) is a lymphodepleting agent approved for active relapsing multiple sclerosis (MS). The impact of CLAD on the adaptive humoral immune system has not sufficiently been studied. This study aimed to assess the influence of CLAD treatment on specific antibody titers to common pathogens. We included 18 MS patients treated with CLAD. Serum IgG antibody levels to measles, mumps, rubella, hepatitis B and varicella zoster virus (VZV), as well as diphtheria and tetanus toxins, were measured prior to the initiation of treatment and at 12 and 24 months after first CLAD administration. Moreover, specimens were longitudinally analyzed regarding absolute blood concentrations of IgG and main lymphocyte subsets. No reduction in antibody levels against measles, mumps, rubella, VZV, hepatitis B, diphtheria toxin and tetanus toxin associated with CLAD treatment was observed. Loss of seroprotection occurred in <1%. We found no significant impact of CLAD on absolute serum IgG levels. Absolute lymphocyte counts were significantly reduced at the end of each treatment year (p < 0.00001 and p < 0.000001). This study suggests that CLAD does not interfere with the pre-existing humoral immunologic memory in terms of pathogen-specific antibody titers.

Estradiol and COVID-19: Does 17-Estradiol Have an Immune-Protective Function in Women Against Coronavirus?

Objective: Female sex hormones have a pro-inflammatory effect, which may help to minimize inflammation. Estrogen's immunoregulatory properties play a significant role in the bi-directional neuroendocrine-immune activity in females. As a result, sex hormones can play a role in men's high mortality rate from coronavirus-2019 (COVID-19). It is aimed to clarify the role of 17-estradiol (E2) in the battle against COVID-19. Materials and methods: Until April 2021, a study on PubMed was performed. COVID-19, 17-estradiol (E2), immunoregulatory properties, pregnancy, menopausal symptoms, hormonal therapy, ER/ expression on immune cells, and mortality were some of the concepts used in the search. Results: Regulation of pro-inflammatory immune processes against COVID-19 appears to be associated with increased immune function (pro-inflammatory), anti-inflammatory regulation, and antiviral defense. Women with a severe coronavirus infection had higher serum IgG antibody levels than men, and their IgG production was faster in the early stages of infection. 17-estradiol (E2) levels of blood will increase by 100-fold during pregnancy. COVID-19 in pregnant women had a 15-fold lower mortality rate than other women. While menopause replacement therapy (MRT) for pre/post-menopausal women and its effectiveness in reducing COVID-19 infection is debatable. Conclusion: MRT may be considered as a viable treatment option for pre/post-menopause women with coronavirus, referring to the fact that sex hormones reduce inflammatory responses and modulate ACE2 expression. The task's difficulty and achieving the desired outcome seem to be challenging.

S100A4 Is Critical for a Mouse Model of Allergic Asthma by Impacting Mast Cell Activation.

BackgroundThe calcium-binding protein S100A4 demonstrates important regulatory roles in many biological processes including tumorigenesis and inflammatory disorders such as allergy. However, the specific mechanism of the contribution of S100A4 to allergic diseases awaits further clarification.ObjectiveTo address the effect of S100A4 on the regulation of mast cell activation and its impact on allergy.MethodsBone marrow-derived cultured mast cells (BMMCs) were derived from wild-type (WT) or S100A4-/- mice for in vitro investigation. WT and S100A4-/- mice were induced to develop a passive cutaneous anaphylaxis (PCA) model, a passive systemic anaphylaxis (PSA) model, and an ovalbumin (OVA)-mediated mouse asthma model.ResultsFollowing OVA/alum-based sensitization and provocation, S100A4-/- mice demonstrated overall suppressed levels of serum anti-OVA IgE and IgG antibodies and proinflammatory cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung exudates. S100A4-/- mice exhibited less severe asthma signs which included inflammatory cell infiltration in the lung tissue and BALF, and suppressed mast cell recruitment in the lungs. Reduced levels of antigen reencounter-induced splenocyte proliferation in vitro were recorded in splenocytes from OVA-sensitized and challenged mice that lacked S100A4-/-. Furthermore, deficiency in the S100A4 gene could dampen mast cell activation both in vitro and in vivo, evidenced by reduced β-hexosaminidase release and compromised PCA and PSA reaction. We also provided evidence supporting the expression of S100A4 by mast cells.ConclusionS100A4 is required for mast cell functional activation, and S100A4 may participate in the regulation of allergic responses at least partly through regulating the activation of mast cells.

Serum levels of IgG antibodies against Aspergillus fumigatus and the risk of hypersensitivity pneumonitis and other interstitial lung diseases

Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) caused by the inhalation of antigens. Antigen-specific IgG antibodies (sIgG) are used as biomarkers of exposure when diagnosing HP, but little is known about the longitudinal relation between antibody levels and risk of HP or other ILD. In a follow-up design, we explored the relationship between sIgG antibodies against Aspergillus fumigatus and the diagnosis of HP in 647 subjects suspected of HP. We showed that IgG levels above the reference value resulted in a hazard ratio of 9.5 for subsequent HP. Our findings support a relationship between high levels of sIgG against A. fumigatus and risk of HP.

Pertussis seroprevalence among adults of reproductive age (20-39 years) in fourteen European countries.

The reported incidence of pertussis in European countries varies considerably. We aimed to study specific Bordetella pertussis seroprevalence in Europe by measuring serum IgG antibody levels to pertussis toxin (anti-PT IgG). Fourteen national laboratories participated in this study including Belgium, Denmark, Finland, Greece, Hungary, Italy, Lithuania, Malta, Norway, Poland, Portugal, Romania, Spain, and Sweden. Each country collected approximately 250 samples (N=7903) from the age groups 20-29years (N=3976) and 30-39years (N=3927) during 2010-2013. Samples were anonymous residual sera from diagnostic laboratories and were analyzed at the national laboratories by a Swedish reference method, a commercial ELISA kit, or were sent to Sweden for analysis. The median anti-PT IgG concentrations ranged from 4 to 13.6IU/mL. The proportion of samples with anti-PT IgG ≥100IU/mL, indicating a recent infection ranged from 0.2% (Hungary) to 5.7% (Portugal). The highest proportion of sera with anti-PT IgG levels between 50 and <100IU/mL, indicating an infection within the last few years, was found in Portugal (12.3%) and Italy (13.9%). This study shows that the circulation of B.pertussis is quite extensive in adults, aged 20-39years, despite well-established vaccination programs in Europe.

Immunogenicity and safety of the BNT162b2 mRNA COVID-19 vaccine in adult patients with autoimmune inflammatory rheumatic diseases and in the general population: a multicentre study

IntroductionVaccination represents a cornerstone in mastering the COVID-19 pandemic. Data on immunogenicity and safety of messenger RNA (mRNA) vaccines in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited.MethodsA multicentre...

Humoral and Mucosal Antibody Response to RSV Structural Proteins in RSV-Infected Adult Hematopoietic Cell Transplant (HCT) Recipients.

Respiratory syncytial virus (RSV) is an important cause of lower respiratory tract infection in infants, the elderly, and immunocompromised patients. RSV antibodies play a role in preventing reinfection and in clearance of RSV, but data regarding the levels of viral protein-specific antibodies elicited and their contribution to patient recovery from RSV-induced disease are limited. We prospectively enrolled a cohort of RSV-infected adult hematopoietic cell transplant (HCT) recipients (n = 40). Serum and nasal-wash samples were obtained at enrollment (acute samples) and convalescence (convalescent samples). We measured (1) humoral IgG and mucosal IgA binding antibody levels to multiple RSV proteins (F, G, N, P, and M2-1) by Western blot (WB); (2) neutralizing antibody (Nt Ab) titers by microneutralization assay; and (3) palivizumab-like antibody (PLA) concentrations by an ELISA-based competitive binding assay developed in the lab. Finally, we tested for correlations between protein-specific antibody levels and duration of viral shedding (normal: cleared in <14 days and delayed: cleared ≥14 days), as well as RSV/A and RSV/B subtypes. Convalescent sera from HCT recipients had significantly higher levels of anti-RSV antibodies to all 5 RSV structural proteins assayed (G, F, N, P, M2-1), higher Nt Abs to both RSV subtypes, and higher serum PLAs than at enrollment. Significantly higher levels of mucosal antibodies to 3 RSV structural proteins (G, N, and M2-1) were observed in the convalescent nasal wash versus acute nasal wash. Normal viral clearance group had significantly higher levels of serum IgG antibodies to F, N, and P viral proteins, higher Nt Ab to both RSV subtypes, and higher PLA, as well as higher levels of mucosal IgA antibodies to G and M2-1 viral proteins, and higher Nt Ab to both RSV subtypes compared to delayed viral clearance group. Normal RSV clearance was associated with higher IgG serum antibody levels to F and P viral proteins, and PLAs in convalescent serum (p < 0.05). Finally, overall antibody levels in RSV/A- and/B-infected HCT recipients were not significantly different. In summary, specific humoral and mucosal RSV antibodies are associated with viral clearance in HCT recipients naturally infected with RSV. In contrast to the humoral response, the F surface glycoprotein was not a major target of mucosal immunity. Our findings have implications for antigen selection in the development of RSV vaccines.

LB0003 IMMUNOGENICITY AND SAFETY OF THE BNT162b2 mRNA COVID-19 VACCINE IN ADULT PATIENTS WITH AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES AND GENERAL POPULATION: A MULTICENTER STUDY

Background:Vaccination represents a cornerstone in mastering the COVID-19 pandemic. Data on immunogenicity, efficacy, and safety of the novel BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited.Objectives:To investigate the immunogenicity, efficacy, and safety of the BNT162b2 mRNA vaccine in patients with AIIRD compared to the general population.Methods:A prospective multicenter study investigated immunogenicity, efficacy, and safety of the two-dose regimen BNT162b2 mRNA vaccine in adult patients with AIIRD including rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthropathy (axSpA), systemic lupus erythematosus (SLE), connective tissues diseases (CTD), systemic vasculitides, and idiopathic inflammatory myositis (IIM), compared to control subjects without rheumatic diseases or immunosuppressive therapies. Serum IgG antibody levels against SARS-CoV-2 spike S1/S2 proteins were measured 2 - 6 weeks after the second vaccine dose. Seropositivity was defined as IgG ≥15 binding antibody units (BAU)/ml. Post-vaccination efficacy defined as post-vaccination COVID-19 infection and safety were assessed. Pre- and post- vaccination disease activity indices were assessed as appropriate for each disease.Results:A total of 686 AIIRD patients and 121 controls participated into the study. AIIRD patients were significantly older than controls, mean age±SD 56.76±14.88 vs 50.76±14.68, respectively, p&lt;0.0001. A total of 95.2% (n=653) AIIRD patients were treated with immunomodulatory medications.The seropositivity rate was 86% (n=590) in patients with AIIRD compared to 100% in controls (p &lt;0.0001) The level of the S1/S2 antibodies was significantly reduced in AIIRD patients compared to controls (mean± SD 132.9±91.7 vs 218.6±82.06, P&lt;0.0001). In patients with PsA, AxSpA, SLE, and LVV, the seropositive rate was above 90%. In RA, the seropositive rate was 82.1% and the lowest seropositive rate (&lt;40%) was observed in patients with AAV and IIM.Anti-CD20 significantly impaired the vaccine’s immunogenicity, with the lowest seropositivity rate of 39%. The use of GC, mycophenolate mofetil (MMF), and abatacept was associated with a significantly lower rate of seropositivity (Figure 1). MTX significantly reduced the seropositivity in patients treated with MTX monotherapy and in combinations with other treatments (92% and 84%, respectively), although at a lesser magnitude than anti-CD20, MMF, and abatacept. More than 97% of patients treated with anti-cytokine therapies including TNFi, interleukin-17 and interleukin-6 inhibitors had an appropriate immunogenic response when used as monotherapy. The combination of TNFi with MTX significantly reduced the rate of seropositivity to 93%, p=0.04. Age over 65 years, a diagnosis of RA, IIM, ANCA-associated vascilitis, and treatment with GC, MMF, anti-CD20, and abatacept were associated with a reduced likelihood of seropositivity.Figure 1.Seropositivity rate by immunosuppressive treatment.There were no post-vaccination symptomatic cases of COVID-19 among AIIRD patients and one mild case in the control group. Major adverse events in AIIRD patients included death (n=2) several weeks after the second vaccine dose, non-disseminated herpes zoster (n=6), uveitis (n=2), and pericarditis (n=1). Post-vaccination disease activity remained stable in the majority of patients.Conclusion:Vaccination with the BNTb262 vaccine resulted in an adequate immunogenic response with an acceptable safety profile in the majority of patients with AIIRD. Treatment with GC, rituximab, MMF, and abatacept may impair BNT162b2-induced immunogenicity. Postponing administration of rituximab, when clinically feasible, seems to be reasonable to improve vaccine-induced immunogenicity. Holding treatment with abatacept and MMF may be considered on an individual basis.Disclosure of Interests:None declared

Protective Efficacy of Rhomboid-Like Protein 3 as a Candidate Antigen Against Eimeria maxima in Chickens.

Avian coccidiosis brings tremendous economic loss to the poultry industry worldwide. The third generation vaccine, including subunit and DNA vaccines, exhibited promising developmental prospects. In a previous study, we found rhomboid-like protein 3 of Eimeria maxima (EmROM3) was involved in infections by Eimeria species. However, the protective efficacy of EmROM3 against Eimeria maxima (E. maxima) remains unknown. In this study, chickens were intramuscularly immunized with the recombinant protein EmROM3 (rEmROM3) or pVAX1-EmROM3 to determine the EmROM3-induced immune response. The induced humoral immune response was determined by measuring serum IgG antibody levels in immunized chickens. The induced cellular immune response was detected by measuring the transcription level of immune related cytokines and the proportion of T cell subsets of the immunized chickens. Finally, the protective efficacy of the EmROM3 vaccine against E. maxima was evaluated by immunization-challenge trials. Results revealed that the purified rEmROM3 reacted with chicken anti-E. maxima serum. The recombinant plasmid of pVAX1-EmROM3 was transcribed and translated in the injected muscle from the vaccinated chickens. In experimental groups, the IgG titers, proportions of CD4+ and CD8+ T cells, and transcription level of splenic cytokines were significantly increased compared with the control groups. The immunization-challenge trial revealed that immunization with rEmROM3 or pVAX1-EmROM3 led to restored weight gain, alleviated enteric lesion, decreased oocyst output as well as the higher anticoccidial index (ACI), indicating partial protection against E. maxima. These results indicate that EmROM3 is an effective candidate antigen for developing novel vaccines against infection by E. maxima.

Distinct Microbial Signatures between Periodontal Profile Classes

Precise classification of periodontal disease has been the objective of concerted efforts and has led to the introduction of new consensus-based and data-driven classifications. The purpose of this study was to characterize the microbiological signatures of a latent class analysis (LCA)–derived periodontal stratification system, the Periodontal Profile Class (PPC) taxonomy. We used demographic, microbial (subgingival biofilm composition), and immunological data (serum IgG antibody levels, obtained with checkerboard immunoblotting technique) for 1,450 adult participants of the Dental Atherosclerosis Risk in Communities (ARIC) study, with already generated PPC classifications. Analyses relied on t tests and generalized linear models with Bonferroni correction. Men and African Americans had higher systemic antibody levels against most microorganisms compared to women and Caucasians (P < 0.05). Healthy individuals (PPC-I) had low levels of biofilm bacteria and serum IgG levels against most periodontal pathogens (P < 0.05). Subjects with mild to moderate disease (PPC-II to PPC-III) showed mild/moderate colonization of multiple biofilm pathogens. Individuals with severe disease (PPC-IV) had moderate/high levels of biofilm pathogens and antibody levels for orange/red complexes. High gingival index individuals (PPC-V) showed moderate/high levels of biofilm Campylobacter rectus and Aggregatibacter actinomycetemcomitans. Biofilm composition in individuals with reduced periodontium (PPC-VI) was similar to health but showed moderate to high antibody responses. Those with severe tooth loss (PPC-VII) had significantly high levels of multiple biofilm pathogens, while the systemic antibody response to these microorganisms was comparable to health. The results support a biologic basis for elevated risk for periodontal disease in men and African Americans. Periodontally healthy individuals showed a low biofilm pathogen and low systemic antibody burden. In the presence of PPC disease, a microbial-host imbalance characterized by higher microbial biofilm colonization and/or systemic IgG responses was identified. These results support the notion that subgroups identified by the PPC system present distinct microbial profiles and may be useful in designing future precise biological treatment interventions.

Circulating antibodies against leukotoxin A as marker of periodontitis Grades B and C and oral infection with Aggregatibacter actinomycetemcomitans.

The facultative bacterium Aggregatibacter actinomycetemcomitans (Aa) is strongly associated with periodontitis and is occasionally found in periodontally healthy subjects. We aimed to determine the prevalence of salivary Aa among patients with either periodontitis Grade B (periodontitis-B) or Grade C (periodontitis-C), periodontally healthy controls (HCs), and to determine if systemic antibodies against Aa or its virulence factor leukotoxin A (LtxA) may serve as biomarkers that reveal the oral presence of the bacterium and discriminate subjects with periodontitis-C, periodontitis-B, or no periodontitis from each other. Serum and unstimulated saliva samples were collected from patients with periodontitis-C (n = 27), patients with periodontitis-B (n = 34), and HCs (n = 28). Serum level of immunoglobulin G antibodies to fragmented whole Aa and to LtxA were quantified using a bead-based assay. Aa was identified in saliva using quantitative polymerase chain reaction (qPCR). All analyses were adjusted for age, sex, and current smoking status. Aa was present in saliva from 11% of HCs, in 32% of patients with periodontitis-B (P = 0.04 versus HCs), and in 37% of patients with periodontitis-C (P = 0.02 versus HCs). Serum antibodies to fragments of Aa associated significantly with periodontitis-C (P = 0.03), while serum anti-LtxA antibodies associated with both periodontitis-B and periodontitis-C (P = 0.002 and P = 9×10-4 , respectively). Moreover, a significant association between serum anti-LtxA antibodies and Aa count in saliva was observed (P = 0.001). On the basis of serum anti-LtxA antibody levels, patients with periodontitis could be discriminated from HCs (AUC = 0.74 in ROC curve-analysis, P = 0.0003), and carriers of Aa could be discriminated from non-carriers (AUC = 0.78, P <0.0001). Aa is highly prevalent in saliva of patients with periodontitis-B or periodontitis-C. Systemic immunoglobulin G antibodies against LtxA distinguish patients with periodontitis, regardless of grade, from HCs, while their quantity reflects the concurrent bacterial burden in the oral cavity.

Low Virus-Specific IgG Antibodies in Adverse Clinical Course and Outcome of Tick-Borne Encephalitis.

Tick-borne encephalitis (TBE) is associated with a range of disease severity. The reasons for this heterogeneity are not clear. Levels of serum IgG antibodies to TBE virus (TBEV) were determined in 691 adult patients during the meningoencephalitic phase of TBE and correlated with detailed clinical and laboratory parameters during acute illness and with the presence of post-encephalitic syndrome (PES) 2–7 years after TBE. Specific IgG antibody levels ranged from below cut-off value (in 32/691 patients, 4.6%), to 896 U/mL (median = 37.3 U/mL). Patients with meningoencephalomyelitis were more often seronegative (24.3%; 9/37) than those with meningoencephalitis (4.7%; 20/428) or meningitis (1.3%; 3/226). Moreover, patients with antibody levels below cut-off had longer hospitalization (13 versus 8 days); more often required intensive care unit treatment (22% versus 8%) and artificial ventilation (71% versus 21%); and had a higher fatality rate (3/32; 9.4% versus 1/659; 0.2%) than seropositive patients. These results were confirmed when antibody levels, rather than cut-off values, were correlated with clinical parameters including the likelihood to develop PES. Low serum IgG antibody responses against TBEV at the onset of neurologic involvement are associated with a more difficult clinical course and unfavorable long-term outcome of TBE, providing a diagnostic and clinical challenge for physicians.

Poria cocos polysaccharide induced Th1-type immune responses to ovalbumin in mice.

In the present study, we evaluated adjuvant potential of Poria cocos polysaccharide (PCP) on the Th1-type immune responses of C57/BL6 mice against ovalbumin (OVA). We first determined the effect of PCP on maturation of murine bone marrow derived dendritic cells (BMDCs), PCP significantly upregulated surface expression of MHCII, CD40, CD80, CD86 and enhanced production of IL-6 and IL-12p40. In addition, PCP affected receptor-mediated endocytosis, but not pinocytosis in BMDCs. Furthermore, OVA + PCP immunization induced specific cytotoxic CD8+ T cell killing of OVA (257–264) peptide pulsed cell. When mice were immunized subcutaneously in a week interval with OVA + PCP. Serum were collected for measuring OVA-specific antibody and splenocytes were harvested for analyzing CD69, IFN-γ ELISpot and cytokines production. The result indicated that OVA-specific IgG, IgG2a and IgG1 antibody levels in serum were significantly elevated by PCP compared with control. PCP increased OVA-specific IFN-γ-secreting CD8+, CD4+ T cells, promoted CD8+ T cell proliferation and up-regulated Th-1 type (IFN-γ, IL-2) cytokine production. In conclusion, data suggest that PCP enhanced cellular immune response and possess potential as a vaccine adjuvant for Th1 immune response.