Assessment of humoral and cellular immunity induced by the BNT162b2 SARS-CoV-2 vaccine in healthcare workers, elderly people, and immunosuppressed patients with autoimmune disease

Safety, efficacy, and immunogenicity of SARS-CoV-2 mRNA vaccination in children and adult patients with rheumatic diseases: a comprehensive literature review

Patients with autoimmune inflammatory rheumatic diseases (AIIRD) are potentially at a higher risk of contracting the SARS-CoV-2 virus and have poorer outcomes of the infection as a result of their immunocompromised state due to the nature of the underlying autoimmune conditions and immunosuppressant use. mRNA-based vaccines provide a novel approach to establishing immunity against SARS-CoV-2. However, the implications of toll-like receptors (TLRs), type I interferon (IFN) and pro-inflammatory cytokines raise concerns on disease severity and inefficient immune response following mRNA vaccination. The use of immunosuppression to reduce disease activity may have consequential implications on immune responses following SARS-CoV-2 mRNA vaccination. This study systematically reviews the literature on the safety, efficacy, and immunogenicity of SARS-CoV-2 vaccination in patients with autoimmune rheumatic conditions. This comprehensive review was conducted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A comprehensive literature search on "PubMed" and "EMBASE" electronic databases was conducted to identify relevant articles published from January 1, 2020 to August 31, 2023. The search yielded 106 studies. The mRNA-based vaccines were demonstrated to be safe and efficacious in AIIRD patients. Most studies investigating safety and efficacy of the mRNA-based vaccines reported low frequencies of serious adverse events and disease flares and few breakthrough infections after complete vaccination. Immunogenic response, however, appeared to be blunted in this population of patients, particularly in those who received certain immunosuppressive agents such as methotrexate, mycophenolic acid and rituximab. mRNA-based vaccines are generally safe and efficacious and produce adequate humoral response in AIIRD patients. Additional prospective studies are warranted to ascertain the long-term safety and efficacy profile and the duration of mRNA-vaccine induced immune response. This can aid in shaping guidelines surrounding optimal timing for booster doses in AIIRD patients.

Longitudinal Comparison of Three T-Cell Assays and Three Antibody Assays Against SARS-CoV-2 Following Homologous mRNA-1273/mRNA-1273/mRNA-1273 and Heterologous ChAdOx1/ChAdOx1/BNT162b2 Vaccination: A Prospective Cohort in Naïve Healthcare Workers

Background: Cellular and humoral immunity are key to the immune response against SARS-CoV-2, but the comparability and correlation across different assays remain underexplored. This study compares three T-cell and three antibody assays in two vaccine groups. Methods: This prospective longitudinal cohort study involved 46 naïve healthcare workers: a total of 11 in the homologous mRNA-1273 group (three doses) and 35 in the heterologous ChAd group (two ChAd doses followed by a BNT booster). Blood samples were collected at five time points. Cellular immunity was assessed using ELISPOT and two commercial interferon-gamma release assays: (IGRA)-QuantiFERON SARS-CoV-2 (QF) and Covi-FERON ELISA (CoVF). Humoral immunity was evaluated using total and IgG antibody assays and a surrogate virus neutralization test. Results: The mRNA-1273 group exhibited stronger and more consistent responses than the ChAd group. The correlations between ELISPOT and IGRA varied from weak to moderate (ρ = 0.300-0.410), while QF-IGRA and CoVF-IGRA showed stronger correlations (ρ = 0.700-0.737). The ELISPOT assay showed substantial agreement with QF [Ag2]-IGRA (k = 0.697-0.774) and CoVF [O-sp]-IGRA (k = 0.641-0.718), and an 80.4% agreement rate (k = 0.608) was found between the QF [Ag2]- and CoVF [O-sp]-IGRA tests. Three antibody assays demonstrated very strong correlations with each other and substantial to near-perfect agreement with ELISPOT (k = 0.866-0.949), QF [Ag2]-IGRA (k = 0.807-0.831), and CoVF [O-sp]-IGRA (k = 0.753-0.777). Conclusions: SARS-CoV-2-specific cellular and antibody responses vary by platform and vaccine type, highlighting the importance of measuring both T-cell and B-cell responses using multiple assays to comprehensively assess immune status.

Cellular Immunity of SARS-CoV-2 in the Borriana COVID-19 Cohort: A Nested Case-Control Study

Our goal was to determine the cellular immune response (CIR) in a sample of the Borriana COVID-19 cohort (Spain) to identify associated factors and their relationship with infection, reinfection and sequelae. We conducted a nested case-control study using a randomly selected sample of 225 individuals aged 18 and older, including 36 individuals naïve to the SARS-CoV-2 infection and 189 infected patients. We employed flow-cytometry-based immunoassays for intracellular cytokine staining, using Wuhan and BA.2 antigens, and chemiluminescence microparticle immunoassay to detect SARS-CoV-2 antibodies. Logistic regression models were applied. A total of 215 (95.6%) participants exhibited T-cell response (TCR) to at least one antigen. Positive responses of CD4+ and CD8+ T cells were 89.8% and 85.3%, respectively. No difference in CIR was found between naïve and infected patients. Patients who experienced sequelae exhibited a higher CIR than those without. A positive correlation was observed between TCR and anti-spike IgG levels. Factors positively associated with the TCR included blood group A, number of SARS-CoV-2 vaccine doses received, and anti-N IgM; factors inversely related were the time elapsed since the last vaccine dose or infection, and blood group B. These findings contribute valuable insights into the nuanced immune landscape shaped by SARS-CoV-2 infection and vaccination.

Bridging the gap - estimation of 2022/2023 SARS-CoV-2 healthcare burden in Germany based on multidimensional data from a rapid epidemic panel

OBJECTIVES

Throughout the SARS-CoV-2 pandemic, Germany like other countries lacked adaptive population-based panels to monitor the spread of epidemic diseases.

METHODS

To fill a gap in population-based estimates needed for winter 2022/23 we resampled in the German SARS-CoV-2 cohort study MuSPAD in mid-2022, including characterization of systemic cellular and humoral immune responses by interferon-γ-release assay (IGRA) and CLIA/IVN assay. We were able to confirm categorization of our study population into four groups with differing protection levels against severe COVID-19 courses based on literature synthesis. Using these estimates, we assessed potential healthcare burden for winter 2022/23 in different scenarios with varying assumptions on transmissibility, pathogenicity, new variants, and vaccine booster campaigns in ordinary differential equation models.

RESULTS

We included 9921 participants from eight German regions. While 85% of individuals were located in one of the two highest protection categories, hospitalization estimates from scenario modeling were highly dependent on viral variant characteristics ranging from 30-300% compared to the 02/2021 peak. Our results were openly communicated and published to an epidemic panel network and a newly established modeling network.

CONCLUSIONS

We demonstrate feasibility of a rapid epidemic panel to provide complex immune protection levels for inclusion in dynamic disease burden modeling scenarios.

Association Between Low Anti-spike Antibody Levels After the Third Dose of SARS-CoV-2 Vaccination and Hospitalization due to Symptomatic Breakthrough Infection in Kidney Transplant Recipients

Background

Whether anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody levels post-third coronavirus disease (COVID-19) vaccination correlate with worse outcomes due to breakthrough infection is unclear. We evaluated the association between anti-SARS-CoV-2 antibody levels and symptomatic breakthrough infection or hospitalization during the Omicron surge in kidney transplant recipients.

Methods

In total, 287 kidney transplant recipients expected to receive a third vaccination were enrolled between November 2021 and February 2022. The Abbott SARS-CoV-2 IgG II Quant test (Abbott, Chicago, IL, USA) was performed within three weeks before and four weeks after the third vaccination. The incidence of symptomatic breakthrough infection and hospitalization from two weeks to four months post-third vaccination was recorded.

Results

After the third vaccination, the seropositive rate and median antibody titer of the 287 patients increased from 57.1% to 82.2% and from 71.7 (interquartile range [IQR] 7.2-402.8) to 1,612.1 (IQR 153.9-5,489.1) AU/mL, respectively. Sixty-four (22.3%) patients had symptomatic breakthrough infections, of whom 12 required hospitalization. Lower anti-receptor-binding domain (RBD) IgG levels (<400 AU/mL) post-third vaccination were a risk factor for symptomatic breakthrough infection (hazard ratio [HR]=3.46, P<0.001). Anti-RBD IgG levels <200 AU/mL were a critical risk factor for hospitalization (HR=36.4, P=0.007).

Conclusions

Low anti-spike IgG levels after third vaccination in kidney transplant recipients were associated with symptomatic breakthrough infection and, particularly, with hospitalization during the Omicron surge. These data can be used to identify patients requiring additional protective measures, such as passive immunization using monoclonal antibodies.

Role of MR-proADM and Monocyte CD169 in Predicting In-Hospital and 60-Day Mortality in COVID-19 Patients

Objectives

Mid-regional pro-adrenomedullin (MR-proADM) and monocyte CD169 (CD169) are valuable prognostic indicators of severe COVID-19.

Methods

We assessed the predictive ability of a single measurement of MR-proADM and CD169 at emergency department (ED) admission to forecast in-hospital and 60-day mortality in adult COVID-19 patients. We analyzed clinical and laboratory data, with in-hospital mortality as the primary endpoint and 60-day mortality as the secondary endpoint. We examined associations with clinical and laboratory variables through univariate and multivariate analyses.

Results

Data from 382 patients over 14 months were analyzed. Significant predictors of in-hospital mortality included age ⩾ 70 years (hazard ratio [HR] 8.1; 95% confidence interval [CI] 2.2-29.5), CD169 ratio ⩾ 20 (HR: 2.4; 95%CI: 1.6-5.6), MR-proADM ⩾ 1.1 mmol/L (HR: 5.1; 95%CI: 1.7-15.6), the need for invasive mechanical ventilation (HR: 6.8; 95%CI: 2.4-19.1), and active cancer (HR: 5.2; 95%CI: 1.8-15.2). For 60-day mortality, only elevated MR-proADM levels showed predictive value (HR: 6.7; 95%CI: 1.7-25.0), while high serologic titer was protective (HR: 0.4; 95%CI: 0.1-0.9).

Conclusion

A single MR-proADM and CD169 measurement upon ED admission has prognostic value for in-hospital mortality, with MR-proADM also predicting 60-day mortality.

Humoral and Cell-Mediated Responses to SARS-CoV-2 Vaccination in a Cohort of Immunodeficient Patients

This study delves into the intricate landscape of SARS-CoV-2 vaccine response in immunodeficient patients, focusing on the dynamics of both humoral and cell-mediated immunity. The cohort includes patients with common variable immunodeficiency (CVI), agammaglobulinemia (XLA), and combined immunodeficiency (CI). The findings reveal varying degrees of antibody production, with XLA patients exhibiting no measurable response but displaying a robust T-cell-mediated response. The study emphasizes the importance of considering both arms of the immune system in assessing vaccine immunogenicity, particularly in the context of immunodeficiency. The results challenge conventional measures of vaccine efficacy only based on antibody titers, highlighting the need for a more comprehensive understanding of the immune response in this vulnerable population. This research contributes valuable insights to guide clinical decisions regarding vaccination strategies, booster doses, and overall protection in immunodeficient individuals.

Efficacy, Immunogenicity, and Safety of COVID-19 Vaccines in Patients with Autoimmune Diseases: A Systematic Review and Meta-Analysis

Patients with autoimmune diseases are among the susceptible groups to COVID-19 infection because of the complexity of their conditions and the side effects of the immunosuppressive drugs used to treat them. They might show impaired immunogenicity to COVID-19 vaccines and have a higher risk of developing COVID-19. Using a systematic review and meta-analysis, this research sought to summarize the evidence on COVID-19 vaccine efficacy, immunogenicity, and safety in patients with autoimmune diseases following predefined eligibility criteria. Research articles were obtained from an initial search up to 26 September 2022 from PubMed, Embase, EBSCOhost, ProQuest, MedRxiv, bioRxiv, SSRN, EuroPMC, and the Cochrane Center of Randomized Controlled Trials (CCRCT). Of 76 eligible studies obtained, 29, 54, and 38 studies were included in systematic reviews of efficacy, immunogenicity, and safety, respectively, and 6, 18, and 4 studies were included in meta-analyses for efficacy, immunogenicity, and safety, respectively. From the meta-analyses, patients with autoimmune diseases showed more frequent breakthrough COVID-19 infections and lower total antibody (TAb) titers, IgG seroconversion, and neutralizing antibodies after inactivated COVID-19 vaccination compared with healthy controls. They also had more local and systemic adverse events after the first dose of inactivated vaccination compared with healthy controls. After COVID-19 mRNA vaccination, patients with autoimmune diseases had lower TAb titers and IgG seroconversion compared with healthy controls.

Humeral and cellular immune responses to SARS-CoV-2 vaccination in patients on peritoneal dialysis

BACKGROUND

Patients with chronic kidney disease are at high risk for coronavirus disease 2019. Little is known about immune response to severe acute respiratory syndrome coronavirus 2 vaccination in patients on peritoneal dialysis (PD).

METHOD

We prospectively enrolled 306 PD patients receiving two doses of vaccines (ChAdOx1-S: 283, mRNA-1273: 23) from July 2021 at a medical center. Humeral and cellular immune responses were assessed by anti-spike IgG concentration and blood T cell interferon-γ production 30 days after vaccination. Antibody ≥0.8 U/mL and interferon-γ ≥ 100 mIU/mL were defined as positive. Antibody was also measured in 604 non-dialysis volunteers (ChAdOx1-S: 244, mRNA-1273: 360) for comparison.

RESULT

PD patients had less adverse events after vaccinations than volunteers. After the first dose of vaccine, the median antibody concentrations were 8.5 U/mL and 50.4 U/mL in ChAdOx1-S group and mRNA-1273 group of PD patients, and 66.6 U/mL and 195.3 U/mL in ChAdOx1-S group and mRNA-1273 group of volunteers, respectively. And after the second dose of vaccine, the median antibody concentrations were 344.8 U/mL and 9941.0 U/mL in ChAdOx1-S group and mRNA-1273 group of PD patients, and 620.3 U/mL and 3845.0 U/mL in ChAdOx1-S group and mRNA-1273 group of volunteers, respectively. The median IFN-γ concentration was 182.8 mIU/mL in ChAdOx1-S group, which was substantially lower than the median concentration 476.8 mIU/mL in mRNA-1273 group of PD patients.

CONCLUSION

Both vaccines were safe and resulted in comparable antibody seroconversion in PD patients when compared with volunteers. However, mRNA-1273 vaccine induced significantly higher antibody and T cell response than ChAdOx1-S in PD patients. Booster doses are recommended for PD patients after two doses of ChAdOx1-S vaccination.

BNT162b2 Elicited an Efficient Cell-Mediated Response against SARS-CoV-2 in Kidney Transplant Recipients and Common Variable Immunodeficiency Patients

SARS-CoV-2 vaccination is the standard of care for the prevention of COVID-19 disease. Although vaccination triggers both humoral and cellular immune response, COVID-19 vaccination efficacy is currently evaluated by measuring antibodies only, whereas adaptative cellular immunity is unexplored. Our aim is to test humoral and cell-mediated response after three doses of BNT162b vaccine in two cohorts of fragile patients: Common Variable Immunodeficiency (CVID) patients and Kidney Transplant Recipients (KTR) patients compared to healthy donors. We enrolled 10 healthy controls (HCs), 19 CVID patients and 17 KTR patients. HC BNT162b third dose had successfully mounted humoral immune response. A positive correlation between Anti-Spike Trimeric IgG concentration and neutralizing antibody titer was also observed. CVID and KTR groups showed a lower humoral immune response compared to HCs. IFN-γ release induced by epitopes of the Spike protein in stimulated CD4+ and CD8+ T cells was similar among vaccinated HC, CVID and KTR. Patients vaccinated and infected showed a more efficient humoral and cell-mediated response compared to only vaccinated patients. In conclusion, CVID and KTR patients had an efficient cell-mediated but not humoral response to SARS-CoV-2 vaccine, suggesting that the evaluation of T cell responses could be a more sensitive marker of immunization in these subjects.

Humoral and Cellular Response and Associated Variables Nine Months following BNT162b2 Vaccination in Healthcare Workers

In this study, we aimed to illustrate the trajectory of humoral and cellular immunity nine months after primary vaccination with the BNT162b2 mRNA vaccine among 189 healthcare workers (HCWs). Additionally, we endeavored to identify correlations between immunity parameters and a number of common variables and comorbidities. A total of 189 healthcare workers (HCWs), vaccinated against COVID-19, were finally included in the study. All of the subjects had received two doses of the BNT162b2 vaccine; had undergone antibody tests one, four and nine months post-vaccination; and had completed a medical questionnaire. Further samples taken at nine months were tested for cellular immunity. No participants had evidence of COVID-19 infection pre- or post-vaccination. An anti-S1 receptor binding domain (RBD) antibody assay was used to assess humoral response, and cellular immunity was estimated with an INF-γ release assay (IGRA). Statistical analysis was performed using STATA. We report a statistically significant antibody drop over time. Being above the age of 40 or a smoker reduces the rise of antibodies by 37% and 28%, respectively. More than half of the participants did not demonstrate T-cell activation at nine months. Female gender and antibody levels at four months predispose detection of cellular immunity at nine months post-immunization. This study furthers the qualitative, quantitative, and temporal understanding of the immune response to the BNT162b2 mRNA vaccine and the effect of correlated factors.

CVAPPS: A Cross-Sectional Study of SARS-CoV-2 Vaccine Acceptance, Perceptions, and Post-Vaccination Side Effects among Rheumatic Disease Patients in Kuwait

Purpose: We analyzed data collected for ascertaining severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine acceptance, perceptions, and post-vaccination side effects among Kuwaiti inflammatory rheumatic disease (IRD) patients. Methods: The current cross-sectional study was conducted on patients attending governmental rheumatology clinics across seven hospitals in Kuwait between July and September 2021. We included adults of both sexes who are national/residents of the state of Kuwait and who had a confirmed diagnosis of any IRD disease. Data on patients’ demographics, history of IRD, SARS-CoV-2 infection, vaccination status, as well as post-vaccination side effects and disease flare were collected from the included participants through a self-administered questionnaire. Stata MP/17 for macOS was used for statistical analyses. Results: We included 501 IRD patients, a group with a mean age of 43.38 years and a mean disease duration of 10.46 years. The majority of the included patients were female (79.8%), and the most common primary rheumatology diagnosis was rheumatoid arthritis (42.5%), followed by spondyloarthritis (19.4%) and systemic lupus erythematosus (19.0%). One hundred and five patients (21.0%) had SARS-CoV-2 infection confirmed by PCR-positive swab; of them, 17 patients were hospitalized. None of the included patients were using steroids alone. cDMARDs, bDMARDs, and sDMARDs were reported in 37.3%, 18.0%, and 3.8% of the patients, respectively. Three hundred and fifty-one patients (70.1%) were vaccinated; 40.9% received Pfizer/BioNTech, whereas 28.7% received AstraZeneca/Oxford vaccines. Fear that the vaccination will aggravate the condition or interfere with the present therapy and concerns about its effectiveness as well as its side effects were the most prevalent causes for refusing to accept the SARS-CoV-2 vaccine. Other patients were worried about the paucity of the data because individuals with IRD had been omitted from earlier research, resulting in a dearth of information. The commonly reported post-vaccination side effects were body ache/pain, fatigue, and pain at the injection site (32.1%, 30.3%, and 29.7%, respectively). IRD flare post-SARS-CoV-2 vaccination was self-reported in only 9 patients, and 342 did not report a flare. Conclusions: This study’s findings highlight that SARS-CoV-2 vaccines have an acceptable safety profile, with the majority of their side effects being temporary and mild. The occurrence of flares was low after immunization. Reassurance and trust in the safety of the SARS-CoV-2 vaccination in IRD patients should be reassuring to rheumatologists and vaccine recipients.

Humoral and cellular response after BNT162b2 vaccine booster in hemodialysis patients and kidney transplant recipients

BACKGROUND

Vulnerable populations, such as hemodialysis (HD) patients and kidney transplant (RTx) recipients, have priority for anti-COVID-19 vaccination, because of their impaired immune status. Here, we investigated the immune response after vaccination with BNT162b2 (two doses plus booster) in HD and RTx patients.

METHODS

A prospective, observational study was started in two homogeneous groups of 55 HD and 51 RTx patients previously matched from a cohort of 336 patients. Anti-RBD IgG levels, assayed after the second dose with BNT162b2 mRNA, were used to stratify subjects into quintiles. After the second dose and after booster, anti-RBD and IGRA test were evaluated in RTx and HD, belonging to the first and fifth quintiles.

RESULTS

After the second dose of vaccine, the median circulating levels of anti-RBD IgG were significantly higher in HD (1456 AU/mL) compared to RTx (27.30 AU/mL). IGRA test showed significantly higher values in the HD (382 mIU/mL) compared with the RTx (73 mIU/mL). After the booster, humoral response increased significantly in both HD (p = 0.0002) and RTx groups (p = 0.009), whereas the T-cellular immunity remained essentially stable in most patients. In RTx patients with a low humoral response after the second dose, the third dose did not significantly strengthen either humoral or cellular immunity.

CONCLUSIONS

For HD and RTx, there is great variability in the humoral response to anti-COVID-19 vaccination, with a stronger response in the HD group. The booster dose was ineffective at reinforcing the humoral and cellular immune response in most RTx patients hyporesponsive to the second dose.

Cellular and humoral immunogenicity of the COVID-19 vaccine and COVID-19 disease severity in individuals with immunodeficiency

Background

A well-coordinated adaptive immune response is crucial for limiting COVID-19 disease. Some individuals with immunodeficiency are at a high risk of developing severe COVID-19. Therefore, the development of standardized methods for measuring different arms of the vaccine response in the setting of immunodeficiency is of particular interest. In this study, we compared the vaccine response of individuals living with immunodeficiency with healthy controls in terms of interferon gamma (IFN-γ) production and spike protein-specific antibody level post primary COVID-19 vaccination and booster vaccines. Additionally, the disease severity of those individuals who contracted COVID-19 was assessed.

Methods

Whole blood was stimulated overnight from 71 participants and 99 healthy controls. Commercially available PepTivator^® peptide pool and trimeric spike protein stimulation were used. ELISA was used to analyze IFN-γ levels. The total SARS-CoV-2 spike protein antibody titre was measured using a Roche Elecsys^® S total antibody assay. Patient characteristics, COVID-19 infection status and IDDA 2.1 'Kaleidoscope' scores were recorded. Vaccine responses were scored from zero to three.

Results

99% of healthy controls, 89% of individuals with IEI and 76% with secondary immunodeficiency (SID) had an IFN-γ level above the validated reference range after peptide mix stimulation following primary vaccination. There was an increase in IFN-γ levels in patients with inborn errors of immunity (IEI) following the booster vaccine (p = 0.0156). 100% of healthy controls, 70% of individuals living with IEI and 64% of individuals living with SID had detectable spike protein-specific antibody levels following the primary vaccination. 55% of immunodeficiency patients who had mild COVID-19 and 10% with moderate/severe COVID-19 had detectable antibody and IFN-γ levels post vaccine. The mean pre-infection IDDA 2.1 scores were higher in individuals who developed moderate/severe COVID-19 (25.2 compared to 9.41).

Conclusions

Covid whole-blood IGRA is a highly accurate, straightforward and robust assay and can be easily adapted to measure cellular response to COVID-19. A complete evaluation of the vaccine response may be particularly important for individuals living with immunodeficiency. A clinical immunodeficiency score and a validated vaccine response score may be valuable tools in estimating COVID-19 disease risk and identifying individuals living with immunodeficiency who may benefit from enhanced vaccination schedules.

Monitoring of Both Humoral and Cellular Immunities Could Early Predict COVID-19 Vaccine Efficacy Against the Different SARS-CoV2 Variants

Reliable immunoassays are essential to early predict and monitor vaccine efficacy against SARS-CoV-2. The performance of an Interferon Gamma Release Assay (IGRA, QuantiFERON® SARS-CoV-2), and a current anti-spike serological test, compared to a plaque reduction neutralization test (PRNT) taken as gold standard were compared. Eighty vaccinated individuals, whose 16% had a previous history of COVID-19, were included in a longitudinal prospective study and sampled before and two to four weeks after each dose of vaccine. In non-infected patients, 2 doses were required for obtaining both positive IGRA and PRNT assays, while serology was positive after one dose. Each dose of vaccine significantly increased the humoral and cellular response. By contrast, convalescent subjects needed a single dose of vaccine to be positive on all 3 tests. Both IGRA and current serology assay were found predictive of a positive titer of neutralizing antibodies that is correlated with vaccine protection. Patients over 65 or 80 years old had a significantly reduced response. The response tended to be better with the heterologous scheme (vs. homologous) and with the mRNA-1273 vaccine (vs. BNT162b2) in the homologous group, in patients under 55 and under 65 years old, respectively. Finally, decrease intensity or absence of IGRA response and to a less extent of anti-spike serology were also correlated to reinfection which has occurred during the follow up. In conclusion, both IGRA and current anti-spike serology assays could be used at defined thresholds to monitor the vaccine response against SARS-CoV-2 and to simply identify non-responding individuals after a complete vaccination scheme. Two available specific tests (IGRA and anti-spike antibodies) could early assess the vaccine-induced immunity against SARS-CoV-2 at the individual scale, to potentially adapt the vaccination scheme in non-responder patients.

Immunogenicity of SARS-CoV-2 mRNA intramuscular vaccination in patients with muscular disorders

Backgrounds

Little clinical data is available on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients with muscular disorders (MDs). The immunogenicity of SARS-CoV-2 vaccines against MDs, in particular, remains unknown. Thus, this study aimed to confirm the immunogenicity and safety of the SARS-CoV-2 vaccine against MDs.

Methods

All participants were vaccinated with two doses of mRNA vaccines (BNT162b2, Pfizer-BioNTech). The serum samples were collected from each patient on the day of second dose of vaccination, and then, consecutively, after one month, three months, and six months. Anti-SARS-CoV-2 IgG levels were determined using the Abbott SARS-CoV-2 IgG II Quant assay.

Results

We evaluated 75 individuals, including 42 patients with MDs and 33 patients with non-muscular disorders (non-MDs). Non-MD patients primarily include those with severe motor and intellectual disabilities. The median age of the patients was 32 years (range 12-64 years). After one and three months following the second immunization, patients with MDs had lower antibody responses. Furthermore, three months following the second immunization, the proportion of high responders among patients with MDs decreased significantly compared to that among patients without MDs (p-value of less than 0.01). No serious adverse events were observed in patients with or without MDs.

Conclusion

Intensity and latency of antibody response were suppressed in patients with MDs. Although MDs may be a key contributor in predicting the antibody response to SARS-CoV-2 vaccination, SARS-CoV-2 immunization in MDs needs extensive research.

Managing patients who are immunocompromised during the COVID-19 pandemic

ABSTRACT

The COVID-19 pandemic has caused distinct challenges for immunocompromised populations, including disease and social management. This article presents strategies to prevent infection and promote quality of life in patients who are immunocompromised.

Assessing T-Cell Immunity in Kidney Transplant Recipients with Absent Antibody Production after a 3rd Dose of the mRNA-1273 Vaccine

The vulnerable population of kidney transplant recipients (KTRs) are low responders to COVID-19 vaccines, so specific immune surveillance is needed. The interferon-gamma (IFN-γ) release assay (IGRA) is effective in assessing T cell-mediated immunity. We assessed SARS-CoV-2-directed T cell responses in KTRs with absent antibody production after a third dose of the mRNA-1273 vaccine, using two different IGRAs. A cohort of 57 KTRs, who were actively followed up, received a third dose of the mRNA-1273 vaccine. After the evaluation of humoral immunity to SARS-CoV-2, 14 seronegative patients were tested with two commercial IGRAs (SD Biosensor and Euroimmun). Out of 14 patients, one and three samples were positive by IGRAs with Euroimmun and SD Biosensor, respectively. The overall agreement between the two assays was 85.7% (κ = 0.444). In addition, multivariate linear regression analysis showed no statistically significant association between the IFN-γ concentration, and the independent variables analyzed (age, gender, years since transplant, total lymphocytes cells/mcl, CD3+ cells/mcl, CD3+ CD4+ cells/mcl, CD3+ CD8+ cells/mcl, CD19+ cells/mcl, CD3-CD16+CD56+ cells/mcl) (p > 0.01). In a vulnerable setting, assessing cellular immune response to complement the humoral response may be advantageous. Since the two commercial IGRAs showed a good agreement on negative samples, the three discordant samples highlight the need for further investigations.

Immune Profiling Uncovers Memory T-Cell Responses with a Th17 Signature in Cancer Patients with Previous SARS CoV-2 Infection Followed by mRNA Vaccination

Simple Summary

Cancer patients are considered a high-risk group for infectious diseases including COVID-19. The protective effects of vaccination are unclear in oncologic patients, as well as their duration. In this study antibody, T-cell and myeloid cell immunity were evaluated in three cohorts of healthy donors and oncologic patients, including those infected with SARS-CoV-2, BNT162b2-vaccinated (mRNA vaccine), and with previous COVID-19 and subsequently vaccinated. We concluded that vaccination was a poor inductor of cellular immunity towards the S protein. Memory T-cells were only detected in patients and healthy donors with COVID-19 previous to vaccination but with an accentuated Th17 inflammatory profile, together with elevated numbers of circulating neutrophils.

Abstract

It is unclear whether patients with cancer present inherently impaired responses to COVID-19 and vaccination due to their treatments, neoplastic diseases or both. To address this question, immune profiling was performed in three cohorts of healthy donors and oncologic patients: infected with SARS-CoV-2, BNT162b2-vaccinated, and with previous COVID-19 disease and subsequently vaccinated. Cancer patients showed good antibody responses to vaccination, but poor induction of T-cell responses towards the S protein when compared to infection. Following natural infection, the major targets for T-cells were the SARS-CoV-2 structural proteins M and S, but not the N protein. Similar to antibody titers, the T-cell responses quickly decayed after six months post-vaccination. Significant memory T-cell expansion was observed in vaccinated donors only if previously diagnosed with COVID-19 before undergoing vaccination. Oncologic patients with previous COVID-19 followed by vaccination exhibited potent IL-17+ CD4 and CD8 T-cell responses and elevated numbers of circulating neutrophils in peripheral blood.

T cells in SARS-CoV-2 infection and vaccination

While antibodies garner the lion’s share of attention in SARS-CoV-2 immunity, cellular immunity (T cells) may be equally, if not more important, in controlling infection. Both CD8⁺ and CD4⁺ T cells are elicited earlier and are associated with milder disease, than antibodies, and T-cell activation appears to be necessary for control of infection. Variants of concern (VOCs) such as Omicron have escaped the neutralizing antibody responses after two mRNA vaccine doses, but T-cell immunity is largely intact. The breadth and patient-specific nature of the latter offers a formidable line of defense that can limit the severity of illness, and are likely to be responsible for most of the protection from natural infection or vaccination against VOCs which have evaded the antibody response. Comprehensive searches for T-cell epitopes, T-cell activation from infection and vaccination of specific patient groups, and elicitation of cellular immunity by various alternative vaccine modalities are here reviewed. Development of vaccines that specifically target T cells is called for, to meet the needs of patient groups for whom cellular immunity is weaker, such as the elderly and the immunosuppressed. While VOCs have not yet fully escaped T-cell immunity elicited by natural infection and vaccines, some early reports of partial escape suggest that future VOCs may achieve the dreaded result, dislodging a substantial proportion of cellular immunity, enough to cause a grave public health burden. A proactive, rather than reactive, solution which identifies and targets immutable sequences in SARS-CoV-2, not just those which are conserved, may be the only recourse humankind has to disarm these future VOCs before they disarm us.

Immunosuppressed non-responders to two doses of mRNA SARS-CoV-2 vaccines achieve an immune response comparable to those of immunocompetent individuals after a third dose

The SARS-CoV-2 vaccines trigger the production of neutralizing antibodies to the SARS-CoV-2 spike (S) protein and induce a T cell-mediated immune response. However, the antibody titers that confer protection against the SARS-CoV-2 virus are currently not well-established. While immunocompetent individuals achieve a high level of immune response after SARS-CoV-2 vaccination, it now appears that a high proportion of immunosuppressed or immunocompromised, patients exhibit low or no response to two doses of the vaccines. Most non-responders are on treatment with either glucocorticoids, mycophenolate-mofetil (MMF), the anti-CD20 monoclonal antibody rituximab, calcineurin inhibitors like cyclosporine and tacrolimus, rapamycin (mTOR) signaling cascade inhibitors (i.e., sirolimus and everolimus), azathioprine, or methotrexate given for a variety of diseases including autoimmune disorders, hematological malignancies, and solid cancers, while recipients of solid organ transplants also fall within this category. Recently, several published reports have suggested that a third dose of these vaccines induces an elevated antibody response against the SARS-CoV-2 S protein.

Antibody Responses after Two Doses of COVID-19 mRNA Vaccine in Dialysis and Kidney Transplantation Patients Recovered from SARS-CoV-2 Infection

Background and Objectives: Hemodialysis patients (HD) and kidney transplant recipients (KTRs) have been heavily impacted by COVID-19, showing increased risk of infection, worse clinical outcomes, and higher mortality rates than the general population. Although mass vaccination remains the most successful measure in counteracting the pandemic, less evidence is available on vaccine effectiveness in immunodepressed subjects previously infected and recovered from COVID-19. Materials and Methods: This study aimed at investigating the ability to develop an adequate antibody response after vaccination in a 2-dose series against SARS-CoV-2 in HD patients and KTR that was administered after laboratory and clinical recovery from COVID-19. Results: Comparing SARS-CoV-2 S1/S2 IgG levels measured before and after 2 doses of mRNA vaccine (BNT162b2 vaccine, Comirnaty, Pfizer–BioNTech or mRNA-1273 vaccine, Spikevax, Moderna), highly significant increases of antibody titers were observed. The antibody peak level was reached at 3 months following second dose administration, regardless of the underlying cause of immune depression and the time of pre-vaccine serology assessment after negativization. Conclusions: Our data indicate that HD patients and KTR exhibit a satisfying antibody response to a 2-dose series of mRNA vaccine, even in cases when infection-induced humoral immunity was poor or rapidly fading. Further studies are needed to evaluate the role of booster doses in conferring effective and durable protection in weak patient categories.

Cellular Immune Response to BNT162b2 mRNA COVID-19 Vaccine in a Large Cohort of Healthcare Workers in a Tertiary Care University Hospital

We describe the results of a T-cell immunity evaluation performed after a median elapsed time of 7 months from second-dose BNT162b2 vaccine administration, in a representative sample of 419 subjects from a large cohort of hospital workers. Overall, the Quantiferon SARS-CoV-2 assay detected a responsive pattern in 49.9%, 59.2% and 68.3% of subjects to three different antigenic stimuli from SARS-CoV-2, respectively, with 72.3% of positivity to at least one antigenic stimulus. Potential predictors of cellular response were explored by multivariable analyses; factors associated with positivity to cellular response (to Ag1 antigenic stimulus) were a previous SARS-CoV-2 infection (OR = 4.24, 95% CI 2.34−7.67, p < 0.001), increasing age (per year: OR = 1.03 95% CI 1.01−1.06, p = 0.019 and currently smoking (compared to never smoking) (OR = 1.93, 95% CI 1.11−3.36, p = 0.010). Increasing time interval between vaccine administration and T-cell test was associated with decreasing cellular response (per week of time: OR = 0.94, 95% CI 0.91−0.98, p = 0.003). A blood group A/AB/B (compared to group O) was associated with higher levels of cellular immunity, especially when measured as Ag2 antigenic stimulus. Levels of cellular immunity tended to be lower among subjects that self-reported an autoimmune disorder or an immunodeficiency and among males. Further studies to assess the protective significance of different serological and cellular responses to the vaccine toward the risk of reinfection and the severity of COVID-19 are needed to better understand these findings.

Vaccine Response in the Immunocompromised Patient with Focus on Cellular Immunity

During the last few years, we have experienced a shift in how we evaluate the effectiveness of vaccines [...]

COVID-19 Vaccination in Health Care Workers in Italy: A Literature Review and a Report from a Comprehensive Cancer Center

The coronavirus disease 2019 pandemic still represents a global public health emergency, despite the availability of different types of vaccines that reduced the number of severe cases, the hospitalization rate and mortality. The Italian Vaccine Distribution Plan identified healthcare workers (HCWs) as the top-priority category to receive access to a vaccine and different studies on HCWs have been implemented to clarify the duration and kinetics of antibody response. The aim of this paper is to perform a literature review across a total of 44 studies of the serologic response to COVID-19 vaccines in HCWs in Italy and to report the results obtained in a prospective longitudinal study implemented at the Fondazione IRCCS Istituto Nazionale Tumori (INT) of Milan on 1565 HCWs. At INT we found that 99.81% of the HCWs developed an antibody response one month after the second dose. About six months after the first serology evaluation, 100% of the HCWs were still positive to the antibody, although we observed a significant decrease in its levels. Overall, our literature review results highlight a robust antibody response in most of the HCWs after the second vaccination dose. These figures are also confirmed in our institutional setting seven months after the completion of the cycle of second doses of vaccination.

Immune Response to Third Dose BNT162b2 COVID-19 Vaccine Among Kidney Transplant Recipients-A Prospective Study

Immune response to two SARS-CoV-2 mRNA vaccine doses among kidney transplant recipients (KTRs) is limited. We aimed to evaluate humoral and cellular response to a third BNT162b2 dose. In this prospective study, 190 KTRs were evaluated before and ∼3 weeks after the third vaccine dose. The primary outcomes were anti-spike antibody level >4160 AU/ml (neutralization-associated cutoff) and any seropositivity. Univariate and multivariate analyses were conducted to identify variables associated with antibody response. T-cell response was evaluated in a subset of participants. Results were compared to a control group of 56 healthcare workers. Among KTRs, we found a seropositivity rate of 70% (133/190) after the third dose (37%, 70/190, after the second vaccine dose); and 27% (52/190) achieved levels above 4160 AU/ml after the third dose, compared to 93% of controls. Variables associated with antibody response included higher antibody levels after the second dose (odds ratio [OR] 30.8 per log AU/ml, 95% confidence interval [CI]11-86.4, p < 0.001); and discontinuation of antimetabolite prior to vaccination (OR 9.1,95% CI 1.8-46.5, p = 0.008). T-cell response was demonstrated in 13% (7/53). In conclusion, third dose BNT162b2 improved immune response among KTRs, however 30% still remained seronegative. Pre-vaccination temporary immunosuppression reduction improved antibody response.

Sex, Age, and Ethnic Background Shape Adaptive Immune Responses Induced by the SARS-CoV-2 mRNA Vaccine

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine-induced adaptive responses have been well investigated. However, the effects of sex, age, and ethnic background on the immune responses elicited by the mRNA vaccine remain unclear. Here, we performed comprehensive analyses of adaptive immune responses elicited by the SARS-CoV-2 mRNA vaccine. Vaccine-induced antibody and T cell responses declined over time but persisted after 3 months, and switched memory B cells were even increased. Spike-specific CD4⁺ T and CD8⁺ T cell responses were decreased against the B.1.351 variant, but not against B.1.1.7. Interestingly, T cell reactivity against B.1.617.1 and B.1.617.2 variants was decreased in individuals carrying HLA-A24, suggesting adaptive immune responses against variants are influenced by different HLA haplotypes. T follicular helper cell responses declined with increasing age in both sexes, but age-related decreases in antibody levels were observed only in males, and this was associated with the decline of T peripheral helper cell responses. In contrast, vaccine-induced CD8⁺ T cell responses were enhanced in older males. Taken together, these findings highlight that significant differences in the reactogenicity of the adaptive immune system elicited by mRNA vaccine were related to factors including sex, age, and ethnic background.

The Immunogenicity and Safety of Three Types of SARS-CoV-2 Vaccines in Adult Patients with Immune-Mediated Inflammatory Diseases: A Longitudinal Cohort Study

Patients with immune-mediated inflammatory diseases (IMID) were seldom enrolled in the studies of SARS-CoV-2 vaccines, and real-world data regarding the immunogenicity of different types of vaccines is limited. We aimed to assess the immunogenicity and safety of three types of vaccines (AZD1222, mRNA-1273, and BNT162b2) in 253 patients with IMID and 30 healthcare workers (HCWs). Plasma levels of IgG-antibody against SARS-CoV-2 targeting the receptor-binding domain of spike protein (anti-S/RBD-IgG) were determined by chemiluminescent immunoassay 3–4 weeks after the first-dose and second-dose vaccination. The positive rate and titers of anti-S/RBD-IgG were significantly higher in mRNA-1273 or BNT162b2 than in the AZD1222 vaccine. Immunogenicity was augmented after the second dose of any vaccine type in all IMID patients, suggesting that these patients should complete the vaccination series. Anti-S/RBD-IgG titers after first-dose vaccination were significantly lower in RA patients than pSS patients, but there was no significant difference after second-dose vaccination among five groups of IMID patients. The positive rate and titers of anti-S/RBD-IgG were significantly lower in patients receiving abatacept/rituximab therapy than in those receiving other DMARDs. All three SARS-CoV-2 vaccines showed acceptable safety profiles, and the common AEs were injection site reactions. We identified SLE as a significant predictor of increased autoimmunity and would like to promote awareness of the possibility of autoimmunity following vaccination.

Immunogenicity, Effectiveness, and Safety of COVID-19 Vaccines in Rheumatic Patients: An Updated Systematic Review and Meta-Analysis

Background: Vaccination is one of the most important measures worldwide to halt the spread of the corona virus disease 2019 (COVID-19). However, the efficacy and safety of these vaccines in rheumatic patients are not well explored. Therefore, we conducted a systematic review and meta-analysis. Methods: We performed a literature search of the PubMed and EMBASE databases on 17 November 2021. Forty-seven studies relevant to the immunogenicity, efficacy/effectiveness, and safety of COVID-19 vaccines were selected. Results: Our results demonstrated that COVID-19 vaccination is effective in protecting rheumatic patients from severe illness caused by the virus. Both the humoral and cellular immunogenicity of vaccines were impaired in rheumatic patients, which were greatly enhanced after the second vaccine dose. Receiving anti-CD20 therapy was associated with impaired humoral immunogenicity. Adverse events due to COVID-19 vaccines in rheumatic patients were similar to those in healthy controls, except for an increased incidence of arthralgia. The incidence of disease flares after COVID-19 vaccination was low. Conclusion: Our systematic review indicated the importance of full vaccination in rheumatic patients. Withholding anti-CD20 therapy was found to be potentially beneficial for the immunogenicity. Furthermore, the vaccines were found to be safe in general. Despite significant heterogeneity between studies, we recommend that rheumatic patients receive these vaccines amidst the global pandemic.

B- and T-Cell Responses After SARS-CoV-2 Vaccination in Patients With Multiple Sclerosis Receiving Disease Modifying Therapies: Immunological Patterns and Clinical Implications

Background

Vaccination campaign to contrast the spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has raised the issue of vaccine immunogenicity in special populations such as people with multiple sclerosis (PwMS) on highly effective disease modifying treatments (DMTs). While humoral responses to SARS-CoV-2 mRNA vaccines have been well characterized in the general population and in PwMS, very little is known about cell-mediated responses in conferring protection from SARS-CoV-2 infection and severe coronavirus disease-2019 (COVID-19).

Methods

PwMS on ocrelizumab, fingolimod or natalizumab, vaccinated with two doses of mRNABNT162b2 (Comirnaty^®) vaccine were enrolled. Anti-Spike (S) and anti-Nucleoprotein (N) antibody titers, IFN-gamma production upon S and N peptide libraries stimulation, peripheral blood lymphocyte absolute counts were assessed after at least 1 month and within 4 months from vaccine second dose administration. A group of age and sex matched healthy donors (HD) were included as reference group. Statistical analysis was performed using GraphPad Prism 8.2.1.

Results

Thirty PwMS and 9 HDs were enrolled. All the patients were negative for anti-N antibody detection, nor reported previous symptoms of COVID-19. Peripheral blood lymphocyte counts were assessed in PwMS showing: (i) reduction of circulating B-lymphocytes in PwMS on ocrelizumab; (ii) reduction of peripheral blood B- and T-lymphocyte absolute counts in PwMS on fingolimod and (iii) normal B- and T-lymphocyte absolute counts with an increase in circulating CD16+CD56+ NK-cells in PwMS on natalizumab. Three patterns of immunological responses were identified in PwMS. In patients on ocrelizumab, anti-S antibody were lacking or reduced, while T-cell responses were normal. In patients on fingolimod both anti-S titers and T-cell mediated responses were impaired. In patients on natalizumab both anti-S titers and T-cell responses were present and comparable to those observed in HD.

Conclusions

The evaluation of T-cell responses, anti-S titers and peripheral blood lymphocyte absolute count in PwMS on DMTs can help to better characterize the immunological response after SARS-CoV-2 vaccination. The evaluation of T-cell responses in longitudinal cohorts of PwMS will help to clarify their protective role in preventing SARS-CoV-2 infection and severe COVID-19. The correlation between DMT treatment and immunological responses to SARS-CoV-2 vaccines could help to better evaluate vaccination strategies in PwMS.

Antibody Response to SARS-CoV-2 Vaccination in Patients with Inflammatory Bowel Disease: Results of a Single-Center Cohort Study in a Tertiary Hospital in Germany

BACKGROUND

COVID-19 is a viral disease caused by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), first described in 2019, with a significant impact on everyday life since then. In December 2020, the first vaccine against COVID-19 from BioNTech/Pfizer was approved for the first time. However, little is known about the immune response to vaccination in patients with inflammatory bowel disease (IBD) and immunomodulators or biologics. The aim of our study was to investigate antibody response to SARS-CoV-2 vaccination in patients with IBD receiving immunomodulators or biologics compared to healthy controls.

METHODS

This was a single-center study with a retrospective observational design. Seventy-two patients with ulcerative colitis or Crohn's disease were included. Matching data from 72 healthy employees of our hospital were used as the control group. Data were matched by propensity score to patients with IBD. Blood samples were taken from both groups for antibody response, and both groups received an accompanying questionnaire.

RESULTS

Sixty-five (90.3%) patients of the IBD group reported taking immunomodulatory therapy. The mean antibody level for all IBD patients was 1,257.1 U/mL (standard deviation [SD] 1,109.626) in males and 1,500.1 U/mL (SD 1142.760) in female IBD patients after full vaccination. Compared to the healthy group, reduced antibody response could be detected (IBD group 1,383.76 U/mL SD 1,125.617; control group 1,885.65 U/mL SD 727.572, p < 0.05). In this group, blood samples were taken with an average of 61.9 days after the first vaccination. There was no vaccination failure in the IBD group after 2 vaccinations. After the first vaccination, side effects, including muscle pain, pain at the injection site, and fatigue, were reported more often in IBD patients than in the control group (total symptoms IBD group 58.3%, control group 34.5%, p < 0.007). The opposite occurred after the second vaccination when side effects were higher in the control group (total symptoms IBD group 55.4%, control group 76%, p = 0.077). There was a trend to a reduced immune response in elderly patients. Disease duration and concomitant immunomodulatory therapy (TNF-alpha blockers, interleukin inhibitors, integrin inhibitors, methotrexate, or azathioprine) had no impact on the immune response. However, longer time to last medication given and time passed to vaccination in patients with IBD seems to have a positive impact on antibody levels.

CONCLUSION

Overall, we could show a high antibody response to vaccination with COVID-19 in all patients with IBD after 2 vaccinations. Vaccination was well tolerated, and no other adverse events were detected. Concomitant immunomodulatory therapy (TNF-alpha blockers, interleukin inhibitors, integrin inhibitors, methotrexate, or azathioprine) had no impact on seroconversion. Further evaluation of antibody titers over time is mandatory to detect early the need for re-vaccination in these patients.

COVID-19 mRNA Based Vaccine Immune-Response Assessment in Nursing Home Residents for Public Health Decision

Nursing home residents (NHR) have been targeted as a vaccination priority due to their higher risk of worse outcome after COVID-19 infection. The mRNA-based vaccine BTN2b2 was first approved in Europe for NHRs. The assessment of the specific vaccine immune response (both humoral and cellular) at long term in NHRs has not been addressed yet. A representative sample of 624 NHR subjects in Northern region of Spain was studied to assess immune response against full vaccination with BTN2b2. The anti-S1 antibody levels and specific T cells were measured at two and six months after vaccination. 24.4% of NHR had a previous infection prior to vaccination. The remaining NHR were included in the full vaccination assessment group (FVA). After two months, a 94.9% of the FVA presented anti-S1 antibodies, whereas those seronegative without specific cellular response were 2.54%. At long-term, the frequency of NHR within the FVA group with anti-S1 antibodies at six months were 88.12% and the seronegative subjects without specific cellular response was 8.07%. The cellular immune assays complement the humoral test in the immune vaccine response assessment. Therefore, the cellular immune assessment in NHRs allows for the fine tuning of those seronegative subjects with potential competent immune responses against the vaccine.

A Rapid and Simple Multiparameter Assay to Quantify Spike-Specific CD4 and CD8 T Cells after SARS-CoV-2 Vaccination: A Preliminary Report

mRNA and Adenovirus vaccines for COVID-19 are used to induce humoral and cell-mediated immunity, with the aim to generate both SARS-CoV-2 B and T memory cells. In present study, we described a simple assay to detect and quantify Spike-specific CD4+ and CD8+ T cell responses induced by vaccination in healthy donors and in subjects with B cell compart impairment, in which antibody response is absent due to primary immunodeficiencies or CD20 depleting therapy. We detect and quantified memory T cell immune responses against SARS-CoV-2 evocated by vaccination in both groups, irrespective to the humoral response. Furthermore, we identified TNF-α as the main cytokine produced by T memory cells, after antigen-specific stimulation in vitro, that could be considered, other than IFN-γ, an additional biomarker of induction of T memory cells upon vaccination. Further studies on the vaccine-induced T cell responses could be crucial, not only in healthy people but also in immunocompromised subjects, where antigen specific T cells responses play a protective role against SARS-CoV-2.

Vaccinated Patients Admitted in ICU with Severe Pneumonia Due to SARS-CoV-2: A Multicenter Pilot Study

Background: The aim of this study was to analyze the percentage of patients admitted to the ICU having received the vaccine against COVID-19, to describe the clinical profile of vaccinated patients admitted to the ICU, and to assess the humoral immune response to vaccination. Methods: In this multicenter prospective descriptive cohort study, consecutive critically ill patients with confirmed SARS-CoV-2 pneumonia who received at least one dose of the SARS-CoV-2 vaccine were included. The time of study was from 1 July to 10 August of 2021. Results: Of the 94 consecutive patients from seven Andalusian ICUs admitted during the time of study, 50 (53.2%) received at least one dose of anti SARS-CoV-2 vaccine. No patient was admitted having previously had SARS-CoV-2 infection. The B.1.617.2 (Delta) variant was the most frequently identified, in 80.76% of cases. Patients with a complete vaccination with non-optimal antibody levels were immunocompromised. Fifteen patients were admitted to the ICU with Acute Respiratory Distress Syndrome (ARDS) without having completed their vaccination; the clinical profile was younger and with less comorbidities compared to patients with full vaccination. There were no differences in severity of ARDS. Conclusions: Most of the patients who were admitted to the ICU having received a dose of the vaccine were not optimally vaccinated; fully vaccinated patients who did not obtain optimal serum antibody levels were patients considered immunocompromised.