Reactogenicity and Peak Anti-RBD-S1 IgG Concentrations in Individuals with No Prior COVID-19 Infection Vaccinated with Different SARS-CoV-2 Vaccines.

OBJECTIVE: To investigate the association of immune response with vaccination adverse effects at peak anti-receptor-binding domain spike subunit 1 (anti-RBDS1) IgG after full vaccination with Comirnaty, Spikevax, or Vaxzevria. METHODS: Anti-RBDS1 IgG concentrations after vaccination were determined in healthy adults vaccinated with the Comirnaty, Spikevax, and Vaxzevria vaccines. The association of reactogenicity and peak antibody response after vaccination was tested. RESULTS: Anti-RBDS1 IgG values were significantly higher in the Comirnaty and Spikevax group, compared with the Vaxzevria group (P < .001). Fever and muscle pain were found to be significant independent predictors of peak anti-RBDS1 IgG in the Comirnaty and Spikevax groups (P = .03 and P = .02, respectively). The multivariate model, adjusted for covariates, showed that no association between reactogenicity and peak antibody concentrations was found in the Comirnaty, Spikevax, and Vaxzevria groups. CONCLUSIONS: No association between reactogenicity and peak anti-RBDS1 IgG after vaccination with the Comirnaty, Spikevax, and Vaxzevria vaccine was found.

Durability and determinants of anti-SARS-CoV-2 spike antibodies following the second and third doses of mRNA COVID-19 vaccine.

OBJECTIVES: To examine the differences in durability and its determinants of humoral immunity following 2- and 3-dose COVID-19 vaccination. METHODS: Throughout the pandemic, we evaluated the anti-spike IgG antibody titers of 2- and 3-dose mRNA vaccine recipients over time among the staff of a medical and research center in Tokyo. Linear mixed models were used to estimate trajectories of antibody titers from 14 to 180 days after the last immune-conferred event (vaccination or infection) and compare antibody waning rates across prior infection and vaccination status, and across background factors in infection-naïve participants. RESULTS: A total of 6901 measurements from 2964 participants (median age, 35 years; 30% male) were analyzed. Antibody waning rate (percentage per 30 days [95% CI]) was slower after 3 doses (25% [23-26]) than 2 doses (36% [35-37]). Participants with hybrid immunity (vaccination and infection) had further slower waning rates: 2-dose plus infection (16% [9-22]); 3-dose plus infection (21% [17-25]). Older age, male sex, obesity, coexisting diseases, immunosuppressant use, smoking, and alcohol drinking were associated with lower antibody titers, whereas these associations disappeared after 3 doses, except for sex (lower in female participants) and immunosuppressant use. Antibody waned slightly faster in older participants, females, and alcohol drinkers after 2 doses, whereas it did not differ after 3 doses across except sex. DISCUSSION: The 3-dose mRNA vaccine conferred higher durable antibody titers, and previous infection modestly enhanced its durability. The antibody levels at a given time point and waning speed after 2 doses differed across background factors; however, these differences mostly diminished after 3 doses.

Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Immunogenicity among Chimeric Antigen Receptor T Cell Therapy Recipients.

Patients receiving chimeric antigen receptor T cell (CAR-T) therapy may have impaired humoral responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations owing to their underlying hematologic malignancy, prior lines of therapy, and CAR-T-associated hypogammaglobulinemia. Comprehensive data on vaccine immunogenicity in this patient population are limited. A single-center retrospective study of adults receiving CD19 or BCMA-directed CAR-T therapy for B cell non-Hodgkin lymphoma or multiple myeloma was conducted. Patients received at least 2 doses of SARS-CoV-2 vaccination with BNT162b2 or mRNA-1273 or 1 dose of Ad26.COV2.S and had SARS-CoV-2 anti-spike antibody (anti-S IgG) levels measured at least 1 month after the last vaccine dose. Patients were excluded if they received SARS-CoV-2 monoclonal antibody therapy or immunoglobulin within 3 months of the index anti-S titer. The seropositivity rate (assessed by an anti-S assay cutoff of ≥.8 U/mL in the Roche assay) and median anti-S IgG titers were analyzed. Fifty patients were included in the study. The median age was 65 years (interquartile range [IQR], 58 to 70 years), and the majority were male (68%). Thirty-two participants (64%) had a positive antibody response, with a median titer of 138.5 U/mL (IQR, 11.61 to 2541 U/mL). Receipt of ≥3 vaccines was associated with a significantly higher anti-S IgG level. Our study supports current guidelines for SARS-CoV-2 vaccination among recipients of CAR-T therapy and demonstrates that a 3-dose primary series followed by a fourth booster increases antibody levels. However, the relatively low magnitude of titers and low percentage of nonresponders demonstrates that further studies are needed to optimize vaccination timing and determine predictors of vaccine response in this population.

Clinical outcome of SARS-CoV-2 infections occurring in multiple myeloma patients after vaccination and prophylaxis with tixagevimab/cilgavimab.

Introduction: Patients with multiple myeloma (MM) frequently reported immune impairment with an increased risk for infection-related mortality. We aimed to evaluate the immune response in MM patients vaccinated for SARS-CoV-2 during active treatment. Methods: We enrolled 158 patients affected by active MM or smoldering MM (SMM) and 40 healthy subjects. All subjects received 2 or 3 doses of the BNT162b2 (Pfizer/BioNTech) vaccine, and the anti-spike IgG values were evaluated after every dose. We applied the Propensity Score Matching (PSM) as a consequence of the limited sample size and its heterogeneity to adjust for differences in baseline clinical variables between MM patients who achieved or not a vaccine response after 2 or 3 doses. Results: At 30 days from the second dose, the median antibodies level in MM was 25.2 AU/mL, lower than in SMM and in the control group. The same results were confirmed after the third dose, with lower median anti-spike IgG levels in MM, compared to SMM and control group. Following PSM, lack of response to SARS-CoV-2 complete vaccination plus boost was associated with age more than 70 years old and use of high-dose of steroids. We failed to identify an association between specific treatment types and reduced vaccine response. The use of prophylaxis with tixagevimab/cilgavimab for 40 non-responder patients after 3 doses of vaccine has proven to be an effective and safe approach in reducing the risk of serious illness in the event of a breakthrough SARS-CoV-2 infection, faced with a mild symptomatic course, and in providing protection instead of long-term humoral immune vaccine responses. Following PSM, only the high-risk cytogenetic abnormalities were associated with an increased risk of developing a breakthrough SARS-CoV-2 infection. Conclusion: Monitoring the immune response is fundamental in MM patients that remain highly vulnerable to SARS-CoV-2 despite the vaccine. The use of prophylaxis with tixagevimab/cilgavimab can guarantee better protection from the severe form of the disease.

Antibody response to different COVID-19 vaccines among the migrant workers of Bangladesh.

Background: Due to the ongoing COVID-19 pandemic, various host countries such as Singapore, imposed entry requirements for migrant workers including pre-departure COVID-19 seroconversion proof. To combat COVID-19 worldwide, several vaccines have acquired conditional approval. This study sought to assess antibody levels after immunization with different COVID-19 vaccines among the migrant workers of Bangladesh. Methods: Venous blood samples were collected from migrant workers who were vaccinated with different COVID-19 vaccines (n=675). Antibodies to SARS-CoV-2 spike protein (S) and nucleocapsid protein (N) were determined using Roche Elecsys® Anti-SARS-CoV-2 S and N immunoassay, respectively. Results: All participants receiving COVID-19 vaccines showed antibodies to S-protein, while 91.36% were positive for N-specific antibodies. The highest anti-S antibody titers were found among the workers who completed booster doses (13327 U/mL), received mRNA vaccines Moderna/Spikevax (9459 U/mL) or Pfizer-BioNTech/Comirnaty (9181 U/mL), and reported SARS-CoV-2 infection in the last six months (8849 U/mL). The median anti-S antibody titers in the first month since the last vaccination was 8184 U/mL, which declined to 5094 U/mL at the end of six months. A strong correlation of anti-S antibodies was found with past SARS-CoV-2 infection (p < 0.001) and the type of vaccines received (p <0.001) in the workers.Conclusion: Bangladeshi migrant workers receiving booster doses of vaccine, vaccinated with mRNA vaccines, and having past SARS-CoV-2 infection, mounted higher antibody responses. However, antibody levels waned with time. These findings suggest a need for further booster doses, preferably with mRNA vaccines for migrant workers before reaching host countries.

Immune Dysregulation in Acute SARS-CoV-2 Infection.

Introduction: Neutralizing antibodies have been shown to develop rapidly following SARS-CoV-2 infection, specifically against spike (S) protein, where cytokine release and production is understood to drive the humoral immune response during acute infection. Thus, we evaluated the quantity and function of antibodies across disease severities and analyzed the associated inflammatory and coagulation pathways to identify acute markers that correlate with antibody response following infection. Methods: Blood samples were collected from patients at time of diagnostic SARS-CoV-2 PCR testing between March 2020-November 2020. Plasma samples were analyzed using the MesoScale Discovery (MSD) Platform using the COVID-19 Serology Kit and U-Plex 8 analyte multiplex plate to measure anti-alpha and beta coronavirus antibody concentration and ACE2 blocking function, as well as plasma cytokines. Results: A total of 230 (181 unique patients) samples were analyzed across the 5 COVID-19 disease severities. We found that antibody quantity directly correlated with functional ability to block virus binding to membrane-bound ACE2, where a lower SARS-CoV-2 anti-spike/anti-RBD response corresponded with a lower antibody blocking potential compared to higher antibody response (anti-S1 r = 0.884, P < 0.001; anti-RBD r = 0.75, P < 0.001). Across all the soluble proinflammatory markers we examined, ICAM, IL-1ß, IL-4, IL-6, TNFα, and Syndecan showed a statistically significant positive correlation between cytokine or epithelial marker and antibody quantity regardless of COVID-19 disease severity. Analysis of autoantibodies against type 1 interferon was not shown to be statistically significant between disease severity groups. Conclusion: Previous studies have shown that proinflammatory markers, including IL-6, IL-8, IL-1ß, and TNFα, are significant predictors of COVID-19 disease severity, regardless of demographics or comorbidities. Our study demonstrated that not only are these proinflammatory markers, as well as IL-4, ICAM, and Syndecan, correlative of disease severity, they are also correlative of antibody quantity and quality following SARS-CoV-2 exposure.

Serological response to vaccination in post-acute sequelae of COVID.

BACKGROUND: Individuals with post-acute sequelae of COVID (PASC) may have a persistence in immune activation that differentiates them from individuals who have recovered from COVID without clinical sequelae. To investigate how humoral immune activation may vary in this regard, we compared patterns of vaccine-provoked serological response in patients with PASC compared to individuals recovered from prior COVID without PASC. METHODS: We prospectively studied 245 adults clinically diagnosed with PASC and 86 adults successfully recovered from prior COVID. All participants had measures of humoral immunity to SARS-CoV-2 assayed before or after receiving their first-ever administration of COVID vaccination (either single-dose or two-dose regimen), including anti-spike (IgG-S and IgM-S) and anti-nucleocapsid (IgG-N) antibodies as well as IgG-S angiotensin-converting enzyme 2 (ACE2) binding levels. We used unadjusted and multivariable-adjusted regression analyses to examine the association of PASC compared to COVID-recovered status with post-vaccination measures of humoral immunity. RESULTS: Individuals with PASC mounted consistently higher post-vaccination IgG-S antibody levels when compared to COVID-recovered (median log IgG-S 3.98 versus 3.74, P < 0.001), with similar results seen for ACE2 binding levels (median 99.1 versus 98.2, P = 0.044). The post-vaccination IgM-S response in PASC was attenuated but persistently unchanged over time (P = 0.33), compared to in COVID recovery wherein the IgM-S response expectedly decreased over time (P = 0.002). Findings remained consistent when accounting for demographic and clinical variables including indices of index infection severity and comorbidity burden. CONCLUSION: We found evidence of aberrant immune response distinguishing PASC from recovered COVID. This aberrancy is marked by excess IgG-S activation and ACE2 binding along with findings consistent with a delayed or dysfunctional immunoglobulin class switching, all of which is unmasked by vaccine provocation. These results suggest that measures of aberrant immune response may offer promise as tools for diagnosing and distinguishing PASC from non-PASC phenotypes, in addition to serving as potential targets for intervention.

Monitoring Temporal Changes in SARS-CoV-2 Spike Antibody Levels and Variant-Specific Risk for Infection, Dominican Republic, March 2021-August 2022.

To assess changes in SARS-CoV-2 spike binding antibody prevalence in the Dominican Republic and implications for immunologic protection against variants of concern, we prospectively enrolled 2,300 patients with undifferentiated febrile illnesses in a study during March 2021-August 2022. We tested serum samples for spike antibodies and tested nasopharyngeal samples for acute SARS-CoV-2 infection using a reverse transcription PCR nucleic acid amplification test. Geometric mean spike antibody titers increased from 6.6 (95% CI 5.1-8.7) binding antibody units (BAU)/mL during March-June 2021 to 1,332 (95% CI 1,055-1,682) BAU/mL during May-August 2022. Multivariable binomial odds ratios for acute infection were 0.55 (95% CI 0.40-0.74), 0.38 (95% CI 0.27-0.55), and 0.27 (95% CI 0.18-0.40) for the second, third, and fourth versus the first anti-spike quartile; findings were similar by viral strain. Combining serologic and virologic screening might enable monitoring of discrete population immunologic markers and their implications for emergent variant transmission.

SARS-CoV-2 Breakthrough Infections after Third Doses Boost IgG Specific Salivary and Blood Antibodies.

SARS-CoV-2 breakthrough infections, associated with waning immunity, increase systemic antibody levels. In this study, we analyzed the impact of the infection timing on the magnitude of the systemic humoral response and whether breakthrough infections also boost antibody levels in the salivary compartment. We observed that the combination of infection plus vaccination, regardless of infection timing, produced a sharp increase in systemic antibodies, which were higher in subjects infected after third doses. Moreover, despite high systemic antibody levels, breakthrough infections after dose three occurred and boosted antibody levels in the salivary compartment. These results suggest that current vaccination strategies against COVID-19 should be improved. Results also showed that determination of salivary antibodies against SARS-CoV-2 could be a valuable tool in disease prevalence studies, for the follow-up of vaccinated individuals, and to assist vaccination strategies against COVID-19, especially in settings where blood sampling cannot be fulfilled.

Photodynamic nasal SARS-CoV-2 decolonization shortens infectivity and influences specific T-Cell responses.

Background: The main objective was to evaluate the efficacy of intranasal photodynamic therapy (PDT) in SARS-CoV-2 mildly symptomatic carriers on decreasing the infectivity period. SARS-CoV-2-specific immune-stimulating effects and safety were also analysed. Methods: We performed a randomized, placebo-controlled, clinical trial in a tertiary hospital (NCT05184205). Patients with a positive SARS-CoV-2 PCR in the last 48 hours were recruited and aleatorily assigned to PDT or placebo. Patients with pneumonia were excluded. Participants and investigators were masked to group assignment. The primary outcome was the reduction in in vitro infectivity of nasopharyngeal samples at days 3 and 7. Additional outcomes included safety assessment and quantification of humoral and T-cell immune-responses. Findings: Patients were recruited between December 2021 and February 2022. Most were previously healthy adults vaccinated against COVID-19 and most carried Omicron variant. 38 patients were assigned to placebo and 37 to PDT. Intranasal PDT reduced infectivity at day 3 post-treatment when compared to placebo with a ß-coefficient of -812.2 (CI95%= -478660 - -1.3, p<0.05) infectivity arbitrary units. The probability of becoming PCR negative (ct>34) at day 7 was higher on the PDT-group, with an OR of 0.15 (CI95%=0.04-0.58). There was a decay in anti-Spike titre and specific SARS-CoV-2 T cell immunity in the placebo group 10 and 20 weeks after infection, but not in the PDT-group. No serious adverse events were reported. Interpretation: Intranasal-PDT is safe in pauci-symptomatic COVID-19 patients, it reduces SARS-CoV-2 infectivity and decelerates the decline SARS-CoV-2 specific immune-responses.

Associations of HLA Polymorphisms with Anti-SARS-CoV-2 Spike and Neutralizing Antibody Titers in Japanese Rheumatoid Arthritis Patients Vaccinated with BNT162b2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019. Anti-SARS-CoV-2 spike (S) and neutralizing antibodies (Abs) are measured to evaluate the efficacy of vaccines. Human leukocyte antigen (HLA) may be associated with vaccine efficacy. Here, we investigated the association of HLA polymorphisms with the production of anti-SARS-CoV-2 S or neutralizing Abs in vaccinated rheumatoid arthritis (RA) patients in Japan. Genotyping of DRB1 and DQB1 was conducted in 87 Japanese RA patients vaccinated with BNT162b2. Associations of allele or haplotype carrier frequencies with anti-SARS-CoV-2 S or neutralizing Abs were examined. DRB1*12:01 was significantly positively associated with the production of S Ab (p = 0.0225, odds ratio [OR] 6.08, 95% confidence interval [CI] 1.32-28.03). The DQB1*03:01 allele carrier frequency tended to be higher in high responders of S Ab. Allele carrier frequencies of DRB1*15:01 (p = 0.0102, OR 9.26, 95% CI 1.65-52.01) and DQB1*06:02 (p = 0.0373, OR 7.00, 95% CI 1.18-41.36) were higher in responders of neutralizing Ab. Haplotype and two-locus analyses of DRB1 and DQB1 suggested that DRB1 alleles were the primary drivers of these associations. Logistic regression analysis showed associations of these alleles independent of clinical characteristics. Independent associations were found between HLA alleles and anti-SARS-CoV-2 Ab production by vaccinated RA patients.

COVID-19 Severity, Cardiological Outcome, and Immunogenicity of mRNA Vaccine on Adult Patients With 22q11.2 DS.

BACKGROUND: The contemporaneous presence of immune defects and heart diseases in patients with 22q11.2 deletion syndrome (22q11.3DS) might represent risk factors for severe coronavirus 2019 disease (COVID-19). OBJECTIVE: To analyze severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outcome in 22q11.2DS patients and immunogenicity of different doses of mRNA SARS-CoV-2 vaccine. METHODS: Longitudinal observational study on SARS-CoV-2 outcome in 60 adults with 22q11.2DS (March 2020-June 2022). Anti-Spike, and anti-receptor binding domain (RBD) antibody responses, generation of Spike-specific memory B cells (MBCs) and Spike-specific T cells at different time points before and after the mRNA BNT162b2 vaccination were evaluated in 16 22q11.2DS patients. RESULTS: We recorded a 95% rate of vaccination, with almost all patients being immunized with the booster dose. Twenty-one patients had SARS-CoV-2 infection. Three patients were infected before vaccine availability, 6 after receiving 2 doses of vaccine, and 12 after one booster dose. The SARS-CoV-2- infection had a mild course, except in one unvaccinated patient with several comorbidities who died from acute respiratory distress syndrome (fatality rate 5%). Infected patients had more frequently moderate/severe intellectual disability, lymphopenia, and lower CD4+ count. Despite major congenital heart diseases, COVID-19 did not impact cardiological conditions. The BNT162b2 vaccine induced S1-immunoglobulin G (IgG) responses, low serum S1-IgA, and slightly impaired specific MBCs response. Specific T-cell responses observed were related to lymphocytes and CD4+ T cell counts. CONCLUSIONS: The SARS-CoV-2 infection had a mild course in most patients with 22q11.2DS, even in patients with major cardiovascular diseases. Immunization induced Spike-specific IgG responses and generated specific MBCs and memory T cells. The weaker memory responses in patients with lymphopenia suggested the need for additional doses.

Antibody-mediated immunity to SARS-CoV-2 spike.

Despite effective spike-based vaccines and monoclonal antibodies, the SARS-CoV-2 pandemic continues more than two and a half years post-onset. Relentless investigation has outlined a causative dynamic between host-derived antibodies and reciprocal viral subversion. Integration of this paradigm into the architecture of next generation antiviral strategies, predicated on a foundational understanding of the virology and immunology of SARS-CoV-2, will be critical for success. This review aims to serve as a primer on the immunity endowed by antibodies targeting SARS-CoV-2 spike protein through a structural perspective. We begin by introducing the structure and function of spike, polyclonal immunity to SARS-CoV-2 spike, and the emergence of major SARS-CoV-2 variants that evade immunity. The remainder of the article comprises an in-depth dissection of all major epitopes on SARS-CoV-2 spike in molecular detail, with emphasis on the origins, neutralizing potency, mechanisms of action, cross-reactivity, and variant resistance of representative monoclonal antibodies to each epitope.

Validation of a SARS-CoV-2 Surrogate Virus Neutralization Test in Recovered and Vaccinated Healthcare Workers.

Vaccination against COVID-19 is the main public health approach to fight against the pandemic. The Spike (S) glycoprotein of SARS-CoV-2 is the principal target of the neutralizing humoral response. We evaluated the analytical and clinical performances of a surrogate virus neutralization test (sVNT) compared to conventional neutralization tests (cVNTs) and anti-S eCLIA assays in recovered and/or vaccinated healthcare workers. Our results indicate that sVNTs displayed high specificity and no cross-reactivity. Both eCLIA and sVNT immunoassays were good at identifying cVNT serum dilutions ≥1:16. The optimal thresholds when identifying cVNT titers ≥1:16, were 74.5 U/mL and 49.4 IU/mL for anti-S eCLIA and sVNT, respectively. Our data show that neutralizing antibody titers (Nab) differ from one individual to another and may diminish over time. Specific assays such as sVNTs could offer a reliable complementary tool to routine anti-S serological assays.

Antibody Responses of SARS-CoV-2 Vaccines amongst Health Care Workers in a Tertiary Care Hospital in Tripura, India: A Cross-Sectional Study.

Background: Vaccines against COVID-19 plays an important role in limiting the spread of SARS-CoV-2 infections and also in curbing mortality and morbidity due to COVID-19. Objective: To estimate the anti-spike antibody response after receiving the second dose of SARS-CoV-2 vaccines amongst health care workers of a tertiary care hospital in Tripura, India. Materials and Method: A cross- sectional study was conducted from 1 July to 20 August 2021 at Agartala Government Medical College and GBP Hospital, Agartala among 561 health care workers who had received first and second doses of SARS-CoV-2 vaccines and had completed 14 days after receiving the second dose. Results: The present study showed that health care workers who had received both doses of COVID-19 vaccine had 99.5% seropositivity to anti-spike antibody. The median SARS-CoV-2 anti-spike antibody titter was 250 with an IQR (211.55-250). Seropositivity rate was higher among Covishield recipients (99.8% [550/551]) as compared to Covaxin recipients (80% [8/10]) and it was found to be statistically significant (P = 0.000). Conclusion: The present study suggests that a good immune response was elicited against spike antigen of SARS-CoV-2 after two complete doses of Covishield (ChAdOx1-nCoV-19) or Covaxin (BBV152).

High Prevalence of Undocumented SARS-CoV-2 Infections in the Pediatric Population of the Tyrolean District of Schwaz.

Complementing the adult seroprevalence data collected at the time of the rapid SARS-CoV-2 mass vaccination in the district of Schwaz in 2021, we set out to establish the seroprevalence of SARS-CoV-2 among the pediatric population of the district. A total of 369 children, mean age 9.9 (SD 3.4), participated in the study, answering a structured questionnaire on the history of SARS-CoV-2 infection, household contacts, symptoms and history of vaccination. We determined binding and neutralizing antibody levels using plasma samples provided. We estimated the overall prevalence of SARS-CoV-2 infection in the general pediatric population at the time of the study using the census data from Statistik Austria and daily reports of officially confirmed cases. Excluding study participants who reported a history of PCR-confirmed infection, the age-standardized seroprevalence of previously unknown SARS-CoV-2 infection among the general pediatric population of the district was 27% (95% CI: 26.1-27.8). Adding this to the officially documented cases, the true overall prevalence was 32.8% (95% CI: 31.9-33.6) in contrast to the officially documented 8.0% (95% CI: 7.5-8.5) by June 2021. This translated into a proportion of 75.7% (95% CI: 74.4-77.0) of cases being officially undocumented, suggesting a high extent of silent SARS-CoV-2 infections in the pediatric population and possibly silent transmission.

Importance of the COVID-19 Vaccine Booster Dose in Protection and Immunity.

BACKGROUND: There is debate on the necessity of booster doses of COVID-19 vaccination, especially in countries with limited resources. METHODS: This cross-sectional study was conducted in a referral laboratory in Tehran, Iran. The level of COVID-19 antibodies was measured and compared between individuals regarding the number of COVID-19 vaccine shots. RESULTS: In this study, 176 individuals with a mean age of 36.3 (±11.7) years participated. A total of 112 individuals received two doses of the COVID-19 vaccine, and 64 individuals received three doses. Level of all antibodies was higher in those who received three doses than in those who received two doses of the COVID-19 vaccine. Considering the SARS-CoV-2 Spike IgG, the difference was not statistically significant but for the SARS-CoV-2 RBD IgG and SARS-CoV-2 NAB the difference was statistically significant. Regarding to the background variables, receiving influenza vaccine in the past year, history of autoimmune diseases and past medical history of chicken pox showed a significant association with the number of vaccine doses received. Their effects on the outcome variables assessed with multivariate logistic regression analysis. CONCLUSION: The results of our study show that a booster dose of the COVID-19 vaccine enhances the antibody response.

Evaluation of Immunogenicity to Three Doses of the SARS-CoV-2 BNT162b2 mRNA Vaccine in Lung Transplant Patients.

The aim of the study was to explore the humoral and T-cell response in lung transplant (LuT) patients. Two-time points were considered, before (T0) and after (Tpost) the third dose of the BNT162b2 mRNA vaccine, comparing LuT with healthy donors (HD). LuT patients showed a lower serologic response against SARS-CoV-2 compared with HD at both time-points (p = 0.0001 and p = 0.0011, respectively). A lower percentage of IFNγ+orIL2+orTNFα+CD4+ and CD8+ T-cells LuT patients was observed in LuT patients compared with HD at T0 (CD4+: p = 0.0001; CD8+: p = 0.0005) and Tpost (CD4+: p = 0.0028; CD8+: p = 0.0114), as well as in the percentage of IFNγ+IL2+TNFα+CD4+ T-cells (T0: p = 0.0247; Tpost: p = 0.0367). Finally, at Tpost, a lower percentage of IFNγ+IL2+TNFα+ CD8+ T-cells in LuT patients compared with HD was found (p = 0.0147). LuT patients were stratified according to the lowest cut-off value for the detection of a humoral response (4.81 BAU/mL) at T0, into responder (R) and non-responder (NR) groups. In the R group, no differences in the percentage of IFNγ+or IL2+orTNFα+ and IFNγ+IL2+TNFα+CD4+ and CD8+ T-cells compared with HD at both time-points were observed. Otherwise, in the NR group, lower percentages of IFNγ+IL2+TNFα+CD4+ T-cells compared with the R group (T0: p = 0.0159; Tpost: p = 0.0159), as well as compared with the HD, at both time-points, were observed (T0: p = 0.0064; Tpost: p = 0.0064). These data seem to confirm that some LuT patients can mount cellular responses even in the absence of a positive humoral response (>33.8 BAU/mL), although this cellular response is dysfunctional and partially detrimental.

Evaluation of Seropositivity After Standard Doses of Vaccination Against SARS-CoV-2 in Patients With Early Breast Cancer Receiving Adjuvant Treatment.

BACKGROUND: Coronavirus disease 2019 (COVID-19) pandemic affected millions of individuals, and patients with cancer are known to be more susceptible. Vaccines against SARS-CoV-2 have been developed and used for patients with cancer, but scarce data are available on their efficacy in patients under active anti-cancer therapies. MATERIALS AND METHODS: In this study, we semi-quantitatively measured the titers of the immunoglobulin G against the anti-spike protein subunit 1 of SARS-CoV-2 after vaccination of patients with early breast cancer undergoing concurrent chemotherapy, endocrinal or targeted non-cytotoxic treatments, and no treatments. RESULTS: Standard doses of COVID-19 vaccines provided sufficient immune responses in patients with early breast cancer, regardless of the type of anticancer therapies. However, the post-vaccination serum anti-spike antibody titers were significantly lower in the patients under cytotoxic chemotherapy. CONCLUSION: Our study emphasizes the importance of the personalized risk stratification and consideration for booster doses in more vulnerable populations.

GNB3 c.825c>T polymorphism influences T-cell but not antibody response following vaccination with the mRNA-1273 vaccine.

Background: Immune responses following vaccination against COVID-19 with different vaccines and the waning of immunity vary within the population. Genetic host factors are likely to contribute to this variability. However, to the best of our knowledge, no study on G protein polymorphisms and vaccination responses against COVID-19 has been published so far. Methods: Antibodies against the SARS-CoV-2 spike protein and T-cell responses against a peptide pool of SARS-CoV-2 S1 proteins were measured 1 and 6 months after the second vaccination with mRNA-1273 in the main study group of 204 participants. Additionally, antibodies against the SARS-CoV-2 spike protein were measured in a group of 597 participants 1 month after the second vaccination with mRNA-1273. Genotypes of GNB3 c.825C>T were determined in all participants. Results: The median antibody titer against the SARS-CoV-2 spike protein and median values of spots increment in the SARS-CoV-2 IFN-γ ELISpot assay against the S1-peptide pool were significantly decreased from months 1 to 6 (p < 0.0001). Genotypes of GNB3 c.825C>T had no influence on the humoral immune response. At month 1, CC genotype carriers had significantly increased T-cell responses compared to CT (p = 0.005) or TT (p = 0.02) genotypes. CC genotype carriers had an almost 6-fold increased probability compared to TT genotype carriers and an almost 3-fold increased probability compared to T-allele carriers to mount a SARS-CoV-2-specific T-cell response above the median value. Conclusion: CC genotype carriers of the GNB3 c.825C>T polymorphism have an increased T-cell immune response to SARS-CoV-2, which may indicate better T-cell-mediated protection against COVID-19 after vaccination with mRNA-1273.