anti-RBD IgG Research Articles

STAR LIGHT Study: XBB.1.5 COVID-19 mRNA Vaccines Boost Systemic but Not Mucosal Immunity Against the SARS-CoV-2 JN.1 Variant in Patients with Chronic Liver Disease

Background: Patients with chronic liver disease (CLD) have impaired vaccine immunogenicity and an excess risk of severe COVID-19. While variant-adapted COVID-19 mRNA vaccines are recommended for vulnerable individuals, their efficacy in patients with CLD has not been studied. Methods: We present the first evaluation of XBB.1.5 COVID-19 vaccine immunogenicity against the SARS-CoV-2 JN.1 variant in patients with CLD. Serum anti-receptor binding domain (RBD) IgG, neutralization, and saliva anti-RBD IgG and IgA against wild-type SARS-CoV-2 (WT) and the XBB.1.5, EG.5.1, BA.2.86, and JN.1 variants were quantified before and 2–4 weeks following a fourth dose of XBB.1.5 mRNA vaccines. Results: Vaccination boosted anti-RBD IgG and neutralization against all tested variants including JN.1 (each p < 0.001). Following immunization, neutralization was lower against JN.1 compared to WT, XBB.1.5, and EG.5.1 (p < 0.001, p < 0.001, and p < 0.01, respectively). Vaccination reduced neutralization failure rates against BA.2.86 and JN.1 (each p < 0.05). The evasion of vaccine-induced antibodies by the tested variants was low, indicated by the positive correlation between anti-RBD IgG and neutralization. At mucosal sites, vaccination boosted anti-RBD IgG (each p < 0.01) but failed to induce infection-blocking IgA (each p > 0.05). Conclusion: XBB.1.5 vaccines protect CLD patients against recent SARS-CoV-2 variants, but developing vaccines with optimized mucosal immunogenicity is required to prevent SARS-CoV-2 transmission and recurrent seasonal COVID-19 outbreaks.

The results of vaccination against novel coronavirus infection in adolescents with allergic diseases

Novel coronavirus infection requires analyzing its course in patients with allergic diseases. Patients with atopic allergic diseases remain insufficiently studied with regard to the peculiarities of the course of both the underlying allergic disease and infectious processes caused by viruses and bacteria. Epithelial cells in bronchial asthma do not respond sufficiently to interferons, suggesting that SARS-CoV-2 infection may suppress spontaneous upregulation of angiotensin-converting enzyme expression, which ultimately reduces disease severity, but at the same time makes patients with allergic atopic diseases susceptible to other viral infections. The results obtained indicate statistically significant differences in the formation of anti-RBD IgG antibodies to SARS-CoV-2 between the group of adolescents with bronchial asthma vaccinated against a new coronavirus infection and those not vaccinated against it. During the follow-up period after 6 months, a statistically significant increase in anti-RBD IgG titer to SARS-CoV-2 due to novel coronavirus infection was observed among the unimmunized children. Clinical parameters indicated a favorable course of atopic process and control of bronchial asthma exacerbations in adolescents who received vaccination against both new coronavirus infection and influenza, while those who did not receive vaccination against these viral infections had bronchial asthma exacerbations due to respiratory infection. Also among patients with bronchial asthma who received influenza vaccination, there were no cases of influenza A and bronchial asthma exacerbations due to respiratory infections. In this regard, influenza vaccination is an important intervention to maintain control of asthma exacerbations. It is noteworthy that no new coronavirus infection was reported among vaccinated adolescents within a year after immunization. At the same time, 6 months after vaccination against a new coronavirus infection, we observed a statistically significant increase in antibody levels in unvaccinated adolescents, indicating the presence of high viral neutralizing activity. Vaccination against novel coronavirus infection in patients with bronchial asthma may be considered a possibility.

COVID-19 mRNA booster vaccination induces robust antibody responses but few adverse events among SARS-CoV-2 naïve nursing home residents

Residents in nursing homes face heightened COVID-19 risks. We aimed to assess the adverse events (AEs) rates and antibody responses after the first to the fifth dose of COVID-19 mRNA vaccination in a nursing home cohort. Ninety-five SARS-CoV-2 naïve participants consisted of 26 staff (median age, 51 years) and 69 residents (median age, 88 years). Life-threatening AEs were reported in neither residents nor staff. The severity of non-life-threatening AEs was graded, and severe AEs were reported only in staff. The AEs rates were considerably lower in residents, compared to those in staff. Anti-RBD IgG and the neutralizing titers (NTs) against Wuhan and Omicron BA.4/BA.5 did not differ significantly between those with ‘any AE’ and ‘no AE’ among both staff and residents two months after the second, third and fifth doses, while the anti-RBD IgG significantly differed between two groups after third dose in residents. These findings suggest that the anti-RBD IgG and the NTs increase regardless of the occurrence of AEs. Our study underscores a robust antibody response in both in staff and residents, and fewer AEs following COVID-19 vaccination in SARS-CoV-2 naïve residents than staff, supporting the recommendation for mRNA booster doses in older adults at high-risk care facilities.

Methotrexate treatment hampers induction of vaccine-specific CD4 T cell responses in patients with IMID

ObjectivesMethotrexate (MTX) is one of the most commonly used medications to treat rheumatoid arthritis (RA). However, the effect of MTX treatment on cellular immune responses remains incompletely understood. This raises...

Monitoring humoral responses against three SARS-CoV-2 vaccines in a university population from Chihuahua, Mexico.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has spread worldwide since 2019. Survey of the antibodies against SARS-CoV-2 is one of the most important measures of immunity since it can give an idea on the effectiveness of administered vaccines and the serologic status of individuals. We determined the concentrations of blood IgM and IgG against three SARS-CoV-2 proteins in vaccinated teachers and students among a university population from Chihuahua, Mexico. Humoral response surveillance against the 3C-like proteinase (3CLpro), nuclear protein (NP), and receptor binding domain (RBD) of SARS-CoV-2 was carried out. A total of 239 samples were analyzed: 67 from teachers who were vaccinated with CanSino and 172 from students (27.9% were vaccinated with AstraZeneca, 32.6% with Sinovac, 24.4% with Pfizer-BioNTech, 15.1% with other vaccines). Significant differences in the levels of IgG were observed between serum from individuals prior to vaccination (preimmunization serum) and from those that were vaccinated with CanSino. However, samples from asymptomatic individuals did not show differences between the preimmunization and post-immunization serum. The three vaccinated groups (AstraZeneca, Pfizer and Sinovac) did not show significant differences in anti-RBD IgG antibody titers compared to the positive control group, except for a Pfizer non-COVID-19 subgroup where the level of antibodies in the Pfizer group was 1.7 times higher. Neither vaccine group showed significant differences between those individuals who previously had COVID-19 and uninfected individuals. These results provide a picture of the situation at the time when in-person classes resumed.

Association between humoral serological markers levels and risk of SARS-CoV-2 infection after the primary COVID-19 vaccine course among ANRS0001S COV-POPART cohort participants

BackgroundWe assessed the prognostic value of serological humoral markers measured one month after the last dose of the primary COVID-19 vaccine course for predicting the risk of severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 infection over the following six months in specific populations.MethodsANRS0001SCOV-POPART is a French nationwide multicenter prospective observational cohort study assessing the immune response to Covid-19 vaccines routinely administered to 11 subgroups of patients with chronic disease and a control group. Participants from the ANRS0001S COV-POPART were included if they received at least two doses of Covid-19 vaccine for the primary vaccine course, had measurements of anti-Spike, anti-receptor binding domain (RBD) IgG-specific or neutralizing antibodies one month after the end of the primary vaccine course, without being infected by SARS-CoV-2 before the measurement. SARS-CoV-2 infections defined by a positive PCR/antigenic test or seroconversion to detectable anti nucleocapsid antibodies were evaluated until the first COVID-19 booster injection. Cox proportional hazards models taking into account interval-censored data were implemented to estimate the association between each antibody level and the risk of SARS-CoV-2 infection. Predictive performances were evaluated by the area under the receiving operating characteristic curve (AUROC).ResultsTwo thousand five hundred seventy adults from a specific population and 1,123 from the control group were included. The cumulative probabilities of SARS-CoV-2 infections at five months after serological measurement were 6.0% 95% confidence interval: [5.0; 7.9] and 10.1% 95% confidence interval: [8.3; 11.9], respectively. Higher levels of anti-Spike IgG antibody were associated with a lower risk of SARS-CoV-2 infections in the control group, but not in the specific populations. Among the specific populations, AUROC were 74.5%, 74.9%, and 72.4% for anti-Spike IgG, anti-RBD IgG, and neutralizing antibodies, respectively. AUROC were superior in the specific populations, 82.0%, 81.2%, and 81.4% for anti-Spike IgG, anti-RBD IgG, and neutralizing antibodies, respectively.ConclusionsVaccine-induced antibody response after the primary course of Covid-19 infection only moderately discriminated between participants developing a SARS-CoV-2 infection during the Omicron wave.Trial registrationNCT04824651 (first posted: 2021-04-01).

Reassuring humoral and cellular immune responses to SARS-CoV-2 vaccination in participants with systemic sclerosis

Individuals with systemic sclerosis (SSc) are particularly susceptible to SARS-CoV-2 infections, yet it remains to be determined if they generate humoral and cellular responses comparable to controls following SARS-CoV-2 vaccinations. Herein, we collected blood and serum after second, third, and fourth SARS-CoV-2 vaccinations in patients with SSc and controls. Following each dose, participants with SSc mounted comparable serum anti-RBD IgG, anti-RBD IgA, and spike-specific CD4+ and CD8+T cell responses to those found in controls. At 3 months post dose 2, the frequencies of Th1, Th2, Th17, and Treg spike-specific CD4+T cells in participants with SSc did not differ from controls. At 2-6 weeks post dose 3, participants with SSc displayed reduced frequencies, but not numbers, of Th17-polarized spike-specific CD4+T cells. Thus, participants with SSc did not display significantly weaker humoral or cellular responses to SARS-CoV-2 vaccination than controls, enabling reassurance of vaccine immunogenicity in participants with SSc.

Longevity of hybrid immunity against SARS-CoV-2 in adults vaccinated with an adenovirus-based COVID-19 vaccine

BackgroundHybrid immunity provides better protection against COVID-19 than vaccination or prior natural infection alone. It induces high magnitude and broadly cross-reactive neutralising anti-Spike IgG antibodies. However, it is not clear how long these potent antibodies last, especially in the context of adenovirus-based COVID-19 vaccines.MethodsWe conducted a longitudinal cohort study and enrolled 20 adults who had received an adenovirus-based COVID-19 vaccine before a laboratory-confirmed SARS-CoV-2 infection. We followed up the study participants for 390 days post the initial breakthrough infection. We assessed the longevity and cross-reactive breadth of serum antibodies against SARS-CoV-2 variants of concern (VOCs), including Omicron.ResultsThe binding anti-Spike IgG antibodies remained within the reported putative levels for at least 360 days and were cross-neutralising against Beta, Gamma, Delta, and Omicron. During the follow up period, a median of one SARS-CoV-2 re-infection event was observed across the cohort, but none resulted in severe COVID-19. Moreover, the re-exposure events were associated with augmented anti-Spike and anti-RBD IgG antibody titres.ConclusionsThis study confirms that hybrid immunity provides durable broadly cross-reactive antibody immunity against SARS-CoV-2 variants of concern for at least a year (360 days), and that it is further augment by SARS-CoV-2 re-exposure.

Long-Term Immunity against SARS-CoV-2 Wild-Type and Omicron XBB.1.5 in Indonesian Residents after Vaccination and Infection.

In the post-pandemic era, evaluating long-term immunity against COVID-19 has become increasingly critical, particularly in light of continuous SARS-CoV-2 mutations. This study aimed to assess the long-term humoral immune response in sera collected in Makassar. We measured anti-RBD IgG levels and neutralization capacity (NC) against both the Wild-Type (WT) Wuhan-Hu and Omicron XBB.1.5 variants across groups of COVID-19-vaccinated individuals with no booster (NB), single booster (SB), and double booster (DB). The mean durations since the last vaccination were 25.11 months, 19.24 months, and 16.9 months for the NB, SB, and DB group, respectively. Additionally, we evaluated the effect of breakthrough infection (BTI) history, with a mean duration since the last confirmed infection of 21.72 months. Our findings indicate fair long-term WT antibody (Ab) titers, with the DB group showing a significantly higher level than the other groups. Similarly, the DB group demonstrated the highest anti-Omicron XBB.1.5 Ab titer, yet it was insignificantly different from the other groups. Although the level of anti-WT Ab titers was moderate, we observed near-complete (96-97%) long-term neutralization against the WT pseudo-virus for all groups. There was a slight decrease in NC against Omicron XBB.1.5 compared to the WT among all groups, as DB group, SB group, and NB group showed 80.71 ± 3.9%, 74.29 ± 6.7%, and 67.2 ± 6.3% neutralization activity, respectively. A breakdown analysis based on infection and vaccine status showed that booster doses increase the NC against XBB.1.5, particularly in individuals without BTI. Individuals with BTI demonstrate a better NC compared to their counterpart uninfected individuals with the same number of booster doses. Our findings suggest that long-term immunity against SARS-CoV-2 persists and is effective against the mutant variant. Booster doses enhance the NC, especially among uninfected individuals.

Interim safety and immunogenicity analysis of the EuCorVac-19 COVID-19 vaccine in a Phase 3 randomized, observer-blind, immunobridging trial in the Philippines.

EuCorVac-19 (ECV-19) is a recombinant receptor binding domain (RBD) COVID-19 vaccine that displays the RBD (derived from the SARS-CoV-2 Wuhan strain) on immunogenic liposomes. This study compares the safety and immunogenicity of ECV-19 to the COVISHIELDTM (CS) adenoviral-vectored vaccine. Interim analysis is presented of a randomized, observer-blind, immunobridging Phase 3 trial in the Philippines in 2600 subjects, with treatment and biospecimen collection between October 2022 and January 2023. Healthy male and female adults who received investigational vaccines were 18 years and older, and randomly assigned to ECV-19 (n = 2004) or CS (n = 596) groups. Immunization followed a two-injection, intramuscular regimen with 4 weeks between prime and boost vaccination. Safety endpoints were assessed in all participants and immunogenicity analysis was carried out in a subset (n = 585 in ECV-19 and n = 290 in CS groups). The primary immunological endpoints were superiority of neutralizing antibody response, as well as noninferiority in seroresponse rate (defined as a 4-fold increase in RBD antibody titers from baseline). After prime vaccination, ECV-19 had a lower incidence of local solicited adverse events (AEs) (12.0% vs. 15.8%, p < 0.01), and solicited systemic AEs (13.1 vs. 17.4%, p < 0.01) relative to CS. After the second injection, both ECV-19 and CS had lower overall solicited AEs (7.8% vs. 7.6%). For immunological assessment, 98% of participants had prior COVID-19 exposure (based on the presence of anti-nucleocapsid antibodies) at the time of the initial immunization, without differing baseline antibody levels or microneutralization (MN) titers against the Wuhan strain in the two groups. After prime vaccination, ECV-19 induced higher anti-RBD IgG relative to CS (1,464 vs. 355 BAU/mL, p < 0.001) and higher neutralizing antibody response (1,303 vs. 494 MN titer, p < 0.001). After boost vaccination, ECV-19 and CS maintained those levels of anti-RBD IgG (1367 vs. 344 BAU/mL, p < 0.001) and neutralizing antibodies (1128 vs. 469 MN titer, p < 0.001). ECV-19 also elicited antibodies that better neutralized the Omicron variant, compared to CS (763 vs. 373 MN titer, p < 0.001). Women displayed higher responses to both vaccines than men. The ECV-19 group had a greater seroresponse rate compared to CS (83% vs. 30%, p < 0.001). In summary, both ECV-19 and CS had favorable safety profiles, with ECV-19 showing diminished local and systemic solicited AE after prime immunization. ECV-19 had significantly greater immunogenicity in terms of anti-RBD IgG, neutralizing antibodies, and seroresponse rate. These data establish a relatively favorable safety and immunogenicity profile for ECV-19. The trial is registered on ClinicalTrials.gov (NCT05572879).

Safety and Immunogenicity of the Intranasal Vaccine Candidate Mambisa and the Intramuscular Vaccine Abdala Used as Booster Doses for COVID-19 Convalescents: A Randomized Phase 1-2 Clinical Trial.

A phase 1-2, prospective, multicenter, randomized, open-label clinical trial (Code RPCEC00000382), with parallel groups, involving 1161 participants, was designed to assess the safety and immunogenicity of two Cuban COVID-19 vaccines (Mambisa and Abdala) in boosting COVID-19 immunity of convalescent adults after receiving one dose of either vaccine. The main safety outcome was severe vaccination adverse events occurring in <5% of vaccinees. Main immunogenicity success endpoints were a ≥4-fold anti-RBD IgG seroconversion or a ≥20% increase in ACE2-RBD inhibitory antibodies in >55% of vaccinees in Phase 1 and >70% in Phase 2. Neutralizing antibody titers against SARS-CoV-2 variants were evaluated. Both vaccines were safe-no deaths or severe adverse events occurred. Mild intensity adverse events were the most frequent (>73%); headaches predominated for both vaccines. Phase 1 responders were 83.3% (p = 0.0018) for Abdala. Mambisa showed similar results. Phase 2 responders were 88.6% for Abdala (p < 0.0001) and 74.2% for Mambisa (p = 0.0412). In both phases, anti-RBD IgG titers, inhibition percentages and neutralizing antibody titers increased significantly after the booster dose. Both vaccines were safe and their immunogenicity surpassed the study endpoints.

Cellular and humoral response to SARS-CoV-2 vaccine BNT162b2 in adults with Chronic Kidney Disease G4/5.

The mRNA vaccines have proven to be very effective in preventing severe disease and death from SARS-CoV-2 in the general population. However, in patients with chronic kidney disease (CKD) in dialysis or with kidney transplants (KT) the vaccine responses vary, with severe breakthrough infections as a consequence. In this intervention study we investigated the magnitude and quality of the responses to mRNA vaccination administered prior to kidney replacement therapy (KRT). Twenty patients with CKD G4/5 and nine healthy controls were followed for 12 months after receiving two doses of BNT162b2 four weeks apart and a booster dose after 3–6 months. Induction of anti-Spike and anti-RBD IgG in plasma followed the same kinetics in CKD patients and controls, with a trend towards higher titers in controls. In accordance, there was no differences in the establishment of Spike-specific memory B-cells between groups. In contrast, the CKD patients showed lower levels of anti-Spike IgG in saliva and Spike-specific CD8+ T-cells in blood, possibly influencing the capacity of viral clearance which can contribute to an elevated risk of severe breakthrough infections. In conclusion, we found that CKD patients, despite having a reduced mucosal and cytotoxic immunity to BNT162b2, demonstrated a serological response in plasma similar to healthy controls. This suggests that immunization prior to RRT is efficient and motivated. (EudraCT-nr 2021-000988-68).

Influenza virus strains expressing SARS-CoV-2 receptor binding domain protein confer immunity in K18-hACE2 mice

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease (COVID-19), rapidly spread across the globe in 2019. With the emergence of the Omicron variant, COVID-19 shifted into an endemic phase. Given the anticipated rise in cases during the fall and winter seasons, the strategy of implementing seasonal booster vaccines for COVID-19 is becoming increasingly valuable to protect public health. This practice already exists for seasonal influenza vaccines to combat annual influenza seasons. Our goal was to investigate an easily modifiable vaccine platform for seasonal use against SARS-CoV-2. In this study, we evaluated the genetically modified influenza virus ΔNA(RBD) as an intranasal vaccine candidate for COVID-19. This modified virus was engineered to replace the coding sequence for the neuraminidase (NA) protein with a membrane-anchored form of the receptor binding domain (RBD) protein of SARS-CoV-2. We designed experiments to assess the protection of ΔNA(RBD) in K18-hACE2 mice using lethal (Delta) and non-lethal (Omicron) challenge models. Controls of COVID-19 mRNA vaccine and our lab’s previously described intranasal virus like particle vaccine were used as comparisons. Immunization with ΔNA(RBD) expressing ancestral RBD elicited high anti-RBD IgG levels in the serum of mice, high anti-RBD IgA in lung tissue, and improved survival after Delta variant challenge. Modifying ΔNA(RBD) to express Omicron variant RBD shifted variant-specific antibody responses and limited viral burden in the lungs of mice after Omicron variant challenge. Overall, this data suggests that ΔNA(RBD) could be an effective intranasal vaccine platform that generates mucosal and systemic immunity towards SARS-CoV-2.

Safety and antibody responses of Omicron BA.4/5 bivalent booster vaccine among hybrid immunity with diverse vaccination histories: A cohort study

This cohort study, conducted between July and August 2023, evaluated the adverse events (AEs) and immune response to a bivalent mRNA-1273.222 (containing sequences of the original Wuhan-H1 strain and the Omicron BA.4/5 variant) booster vaccine in 122 participants. The study included individuals with diverse vaccination histories, and their responses were assessed based on anti-receptor binding domain (RBD) IgG levels and neutralizing antibodies against the wild-type, Omicron BA.5, and XBB.1.16 variants. Following administration of the BA.4/5 bivalent vaccine, AEs were generally mild to moderate and well-tolerated within a few days. There were no reports of vomiting and no serious AEs or death. The findings demonstrated robust immune responses, with significant increases in anti-RBD IgG levels, particularly in groups that had received 3 –6 doses before the booster dose. The BA.4/5 bivalent booster effectively induced neutralizing antibodies against the vaccine strains, providing robust neutralization, including the XBB.1.16 strain. The study also highlighted that individuals with hybrid immunity, especially those assumed infected with the BA.5 strain or who had been infected twice, showed higher levels of robust neutralizing activity against Omicron XBB.1.16. Overall, these results indicate that the BA.4/5 bivalent booster vaccines can induce potent and good antibody responses in emerging Omicron subvariants, supporting its efficacy as a booster in individuals with diverse vaccination histories.

Real World Use of Tixagevimab/Cilgavimab Pre-Exposure Prophylaxis of COVID-19 in Immunocompromised Individuals: Data from the OCTOPUS Study.

Objective. We aimed to report the real-world use and outcomes over time in immunocompromised individuals receiving tixagevimab/cilgavimab (T/C) pre-exposure prophylaxis (PrEP). Methods. This observational study included participants who received T/C PrEP, categorized into three groups: (i) No COVID-19 (NoC), i.e., participants who never had COVID-19; (ii) Hybrids (H), i.e., participants who had COVID-19 before PrEP; and (iii) Break-through Infections (BTIs), i.e., participants who had COVID-19 after PrEP. The study measured several immune markers at the administration of T/C (T0) at 3 (T1), 6 (T2), and 9 (T3) months afterward. These markers included: anti-receptor-binding domain (RBD) IgG antibodies; BA.5-neutralizing antibodies (nAbs); mucosal IgG; and T cell immunity. The incidence rate ratios for BTIs were analyzed using a Poisson regression model. Results. A total of 231 participants with a median age of 63 years (IQR 54.0-73.0). were included. Among these, 84% had hematological diseases and received a median of three vaccine doses. N = 72 participants belonged to the NoC group, N = 103 to the H group, and n = 56 to the BTI group (24%), with most BTIs being mild/moderate. The incidence rate (IR) of BTIs was 4.2 per 100 patient-months (95% CI 3.2-5.4), with no associated risk factors identified. There was a significant increase in anti-RBD IgG levels 3 months after the T/C administration in all groups, followed by a decline at 6 months, whereas at the same time points, geometric mean titers (GMTs) of anti-BA.5 nAbs were low for all groups and were around or below the detection threshold. No significant changes were observed in IFN-γ levels. The mucosal immune response was observed only 3 months after the PrEP administration. Conclusion. We provided a real-world experience model on the clinical efficacy of T/C PrEP in preventing severe COVID-19 during the Omicron wave through a comprehensive virological and immunological study. While waiting for the arrival of new monoclonal antibodies that can effectively neutralize the most recent variants, T/C PrEP remains the only viable strategy in the available armamentarium today to prevent COVID-19 complications in an extremely fragile population with suboptimal immune responses to COVID-19 vaccines.

Systemic and Mucosal Immunogenicity of Monovalent XBB.1.5-Adapted COVID-19 mRNA Vaccines in Patients with Inflammatory Bowel Disease.

Recently updated COVID-19 mRNA vaccines encode the spike protein of the omicron subvariant XBB.1.5 and are recommended for patients with inflammatory bowel disease (IBD) on immunosuppressive treatment. Nonetheless, their immunogenicity in patients with IBD against rapidly expanding virus variants remains unknown. This prospective multicenter cohort study is the first study to investigate the immunogenicity of XBB.1.5-adapted vaccines in patients with IBD. Systemic and mucosal antibodies targeting the receptor-binding domains (RBDs) of the omicron subvariants XBB.1.5, EG.5.1, and BA.2.86, as well as their neutralization were quantified before and two to four weeks after vaccination with monovalent XBB.1.5-adapted mRNA vaccines. Vaccination increased levels of serum anti-RBD IgG targeting XBB.1.5, EG.5.1, and BA.2.86 (1.9-fold, 1.8-fold, and 2.6-fold, respectively) and enhanced corresponding neutralization responses (2.3-fold, 3.1-fold, and 3.5-fold, respectively). Following vaccination, anti-TNF-treated patients had reduced virus neutralization compared to patients on treatments with other cellular targets. 11.1% and 16.7% of patients lacked EG.5.1 and BA.2.86 neutralization, respectively; all these patients received anti-TNF treatment. At mucosal sites, vaccination induced variant-specific anti-RBD IgG but failed to induce RBD-targeting IgA. Our findings provide a basis for future vaccine recommendations while highlighting the importance of frequent booster vaccine adaptation and the need for mucosal vaccination strategies in patients with IBD.

Immunogenicity, reactogenicity, and safety of a second booster with BNT162b2 or full-dose mRNA-1273: A randomized VACCELERATE trial in adults aged ≥75 years (EU-COVAT-1-AGED Part B)

ObjectivesTo assess the safety and immunogenicity of a fourth vaccination (second booster) in individuals aged ≥75 years. MethodsParticipants were randomized to BNT162b2 (Comirnaty, 30 µg) or messenger RNA (mRNA)-1273 (Spikevax, 100 µg). The primary end point was the rate of two-fold antibody titer increase 14 days after vaccination, targeting the receptor binding domain (RBD) region of wild-type SARS-CoV-2. The secondary end points included changes in neutralizing activity against wild-type and 25 variants. Safety was assessed by monitoring solicited adverse events (AEs) for 7 days. ResultsA total of 269 participants (mean age 81 years, mRNA-1273 n = 135/BNT162b2 n = 134) were included. Two-fold anti-RBD immunoglobulin (Ig) G titer increase was achieved by 101 of 129 (78%) and 116 of 133 (87%) subjects in the BNT162b2 and the mRNA-1273 group, respectively (P = 0.054). A second booster of mRNA-1273 provided higher anti-RBD IgG geometric mean titer: 21.326 IU/mL (95% confidence interval: 18.235-24.940) vs BNT162b2: 15.181 IU/mL (95% confidence interval: 13.172-17.497). A higher neutralizing activity was noted for the mRNA-1273 group. The most frequent AE was pain at the injection site (51% in mRNA-1273 and 48% in BNT162b2). Participants in the mRNA-1273 group had less vaccine-related AEs (30% vs 39%). ConclusionsA second booster of either BNT162b2 or mRNA-1273 provided substantial IgG increase. Full-dose mRNA-1273 provided higher IgG levels and neutralizing capacity against SARS-CoV-2, with similar safety profile for subjects of advanced age.

Monitoring of adaptive immune responses in healthcare workers who received a Coronavirus disease 2019 vaccine booster dose.

Coronavirus disease 2019 (COVID-19) has become a global pandemic and led to increased mortality and morbidity. Vaccines against the etiologic agent; severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) were approved for emergency use on different platforms. In the early phase of the pandemic, Thai healthcare workers (HCWs) received CoronaVac, an inactivated vaccine, as the first vaccine against SARS-CoV-2, followed by ChAdOx1 nCoV-19, a viral vector-based vaccine, or BNT162b2, an mRNA vaccine, as a booster dose. This preliminary study evaluated the immunogenicity of ChAdOx1 nCoV-19 and BNT162b2 as a booster dose in HCWs who previously received two doses of CoronaVac. Ten HCW participants received ChAdOx1 nCoV-19 and another 10 HCWs received BNT162b2 as a booster dose after two doses of CoronaVac. Anti-RBD IgG, neutralizing antibodies (NAb), and cellular immunity, including interferon-gamma (IFN-γ)-releasing CD4, CD8, double negative T cells, and NK cells, were measured at 3 and 5 months after the booster dose. There was no significant difference in anti-RBD IgG levels at 3 and 5 months between the two different types of booster vaccine. The levels of anti-RBD IgG and NAb were significantly decreased at 5 months. HCWs receiving BNT162b2 had significantly higher NAb levels than those receiving ChAdOx1 nCoV-19 at 5 months after the booster dose. IFN-γ release from CD4 T cells was detected at 3 months with no significant difference between the two types of booster vaccines. However, IFN-γ-releasing CD4 T cells were present at 5 months in the ChAdOx1 nCoV-19 group only. ChAdOx1 nCoV-19 or BNT162b2 can be used as a booster dose after completion of the primary series primed by inactivated vaccine. Although the levels of immunity decline at 5 months, they may be adequate during the first 3 months after the booster dose.

Humoral immune response and safety of Sars-Cov-2 vaccine in people with multiple sclerosis

BackgroundFor the past three years, the pandemic has had a major effect on global public health, mainly on those with underlying medical conditions, such as people living with Multiple Sclerosis. Vaccination among this group is of great importance, and the long-term impacts of vaccination and its safety on the health of these patients will continue to be revealed. Therefore, risks related to vaccination and immune response need to be assessed. The objective here was to characterize the immune response, short-term safety, and the effects of multiple variables on these factors after COVID-19 vaccination (mainly Sinopharm) among people with Multiple Sclerosis. We assessed the short-term safety and humoral SARS-COV-2 anti-RBD IgG response using a data collection form and Immunoassay, respectively.ResultsNo severe adverse events or MS relapse was observed. Myalgia/body pain (26.7%), low-grade fever (22.2%), and mild headache (15.6%) were the most common adverse events. The use and type of vaccine influenced the frequency of side effects with a p-value < 0.0001. Regarding immune response, patients on rituximab and fingolimod had a lower antibody titer compared to other medications. With a significant difference, hybrid immunity (p-value: 0.047) and type of DMTs (p-value: 0.017) affected the humoral response.ConclusionThere is a low incidence of serious adverse effects, MS worsening or relapse after COVID-19 vaccination, and mainly, side effects are similar to that of the general population. It appears that treatment with various disease-modifying therapies does not induce or worsen the post-vaccination side effects, although some, including Rituximab and fingolimod, may affect the immunity induced after vaccination.

Humoral response superiority of the monovalent XBB.1.5 over the bivalent BA.1 and BA.5 mRNA COVID-19 vaccines

JN.1, the dominating SARS-CoV-2 variant, is antigenically distinct from ancestral BA.1, BA.5 and XBB.1.5 variants, raising concern about effectiveness of updated COVID-19 vaccines. Here, we compared the neutralizing antibody response against JN.1, 1-month after receipt of the three available Moderna mRNA vaccines. Sera obtained from 37, 30 and 30 XBB.1.5, BA.1 and BA.4-5 -vaccine recipients, respectively, were tested for anti-RBD IgG and for JN-1 specific neutralizing antibody levels. Geometric mean fold rise (GMFR) in JN.1 specific neutralizing titers was 27 (95 % CI: 17–43.1), 10.1 (95 % CI: 6.48–15.7) and 8.77 (95 % CI: 5.69–13.5) following XBB.1.5, BA.1 and BA.4-5 vaccines, respectively, translating into a 64 % lower adjusted response (geometric mean ratio [GMR] = 0.36, 95 % CI: 0.21–0.6) in the BA.1 arm, and a 75 % lower response (GMR = 0.25, 95 % CI: 0.15–0.43) in the BA.4-5 arm. This suggests that XBB.1.5 vaccination will most likely, result in improved effectiveness against JN.1 compared with other COVID-19 vaccines.