key: cord-0267943-jmf78v6g authors: Uwamino, Y.; Wakui, M.; Yatabe, Y.; Nakagawa, T.; Sakai, A.; Kurafuji, T.; Shibata, A.; Tomita, Y.; Noguchi, M.; Tanabe, A.; Arai, T.; Ohno, A.; Yokota, H.; Uno, S.; Yamasawa, W.; Sato, Y.; Ikeda, M.; Yoshimura, A.; Hasegawa, N.; Saya, H.; Murata, M. title: Anti-SARS-CoV-2 cellular immunity in 571 vaccinees assessed using an interferon-γ release assay date: 2021-12-15 journal: nan DOI: 10.1101/2021.12.14.21267039 sha: 8bac1ac82944616a3aafb992c2ccac22e693f385 doc_id: 267943 cord_uid: jmf78v6g Generation of antigen-specific memory T cells has been analyzed only for few coronavirus disease 2019 (COVID-19) vaccinees, whereas antibody titers have been serologically measured for a large number of individuals. Here, we assessed the anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cellular immune response in a large cohort using interferon (IFN)-{gamma} release assays (IGRAs) based on short-term whole blood culture. The study included 571 individuals who received the viral spike (S) protein-expressing BNT162b2 mRNA SARS-CoV-2 vaccine. Serum IgG titers against the receptor-binding domain (RBD) of S protein were measured. Samples of 28 vaccinees were subjected to flow cytometry analysis of T cells derived from short-term whole blood culture. IFN-{gamma} production triggered by S antigens was observed in most individuals 8 weeks after receiving the second dose of the vaccine, indicating acquisition of T cell memory responses. The frequencies of activated T cell subsets were strongly correlated with IFN-{gamma} levels, supporting the usability of our approach. S antigen-stimulated IFN-{gamma} levels were weakly correlated with anti-RBD IgG titers and associated with pre-vaccination infection and adverse reactions after the second dose. Our approach revealed cellular immunity acquired after COVID-19 vaccination, providing insights regarding the effects and adverse reactions of vaccination. Currently, mass vaccination is underway worldwide to overcome the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The BNT162b2 mRNA SARS-CoV-2 vaccine, which leads to the expression of the viral spike (S) protein in vaccinee cells, is used most frequently [1, 2] . Previously, the antigen-specific memory T cells in only a small number of samples (less than 50) have been assessed, whereas antibody titers have been serologically measured for many vaccinee samples. Although ELISpot assays for detection of antigen-reactive interferon (IFN)-γ production and flow cytometry assays for detection of antigen-specific T cell activation are conventionally used for investigating cellular immunity, the number of samples that can be tested is limited because of the laborious procedures involved [3] [4] [5] [6] [7] . To better understand the immunological aspects of the efficacy of mass COVID-19 vaccination, T cell responses should be assessed along with antibody responses using a larger number of vaccinee samples. Similar to serological assays used as laboratory tests for screening of immunity against Mycobacterium tuberculosis or cytomegalovirus infection, interferon (IFN)-γ All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 5 release assays (IGRAs) based on short-term whole blood culture enable detection of antigen-specific Th1 type responses for a large number of samples [8, 9] . Because of short-term culture, the assay results reflect the memory, but not the naïve T cells, reactive to the antigens used. Therefore, these IGRAs are useful for detecting the acquisition of cellular immunity due to vaccination as well as due to natural infection. Recently, the QuantiFERON SARS-CoV-2 kit (Qiagen, Hilden, Germany) and the SARS-CoV-2 IGRA kit (Euroimmun Medizinische Labordiagnostika, Luebeck, Germany) have been developed for IGRAs based on short-term whole blood culture to functionally detect anti-SARS-CoV-2 T cells [10] [11] [12] [13] . A small feasibility study involving 12 vaccinated individuals has demonstrated the ability of the QuantiFERON SARS-CoV-2 assay to identify T cell responses in COVID-19 vaccinees [10] . Two other studies evaluated the performance of the QuantiFERON SARS-CoV-2 assay in 18 and 22 vaccinated health care workers using samples collected only after vaccination [14, 15] . A recent study assessed cellular immunity acquired by 32 healthy individuals, 58 patients on hemodialysis, 29 patients on peritoneal dialysis, and 90 renal allograft recipients who had received the mRNA vaccine using the QuantiFERON SARS-CoV-2 assay [16] . Impairment of immune responses in 106 and 543 vaccinated patients undergoing hemodialysis was assessed using the QuantiFERON SARS-CoV-2 assay in All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 6 two independent studies [17, 18] . Although the findings from these studies are interesting, they should be supported by observations obtained after using more samples from healthy individuals or by comparing the results obtained using the QuantiFERON SARS-CoV-2 assay with those of conventional assays (ELISpot and flow cytometry). Understanding of not only humoral but also cellular immunity acquired after vaccination is expected to provide insights regarding common or distinct features of immunity in COVID-19 and other viral diseases as well as the effects of immunization. The present study aimed to assess cellular immunity in a large number of individuals who had received the BNT162b2 mRNA SARS-CoV-2 vaccine using IGRAs based on short-term whole blood culture. To confirm the usability of the IGRA based on its correlation with conventional assays, some randomly selected vaccinee samples were simultaneously subjected to flow cytometric analyses of T cells derived from the culture for IGRAs. Of the 593 participants selected in the study, 10 participants who did not receive both doses of the vaccine and 10 participants from whom post-vaccination samples were not collected were excluded from further analyses. The remaining vaccinees were analyzed, All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (Table 1) . To measure T cell responses, blood samples were stimulated with two peptide antigen pools. Antigen 1 (Ag 1) was designed to present epitopes present in the S1 subunit, which are recognized mainly by CD4 + T cells. Antigen 2 (Ag 2) was designed to present epitopes present in S1 and S2 subunits, which are recognized by CD4 + T cells and CD8 + T cells, respectively. In post-vaccine samples, the IFN-γ levels in the supernatant of short-term whole blood culture upon Ag 1 or Ag 2 stimulation differed widely (Fig. 1) . The median IFN-γ levels in post-vaccine samples were higher than those in pre-vaccine samples upon both Ag 1 and Ag 2 stimulation. In case of Ag 1 stimulation, the pre-vaccination samples contained 0.00 IU/mL IFN-γ (IQR: -0.01 to 0.00 IU/mL), while the post-vaccination samples contained 0.35 IU/mL IFN-γ (IQR: 0.14-0.35 IU/mL) (p < 0.001). In case of Ag 2 stimulation, the pre-vaccination samples All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 8 contained 0.00 IU/mL IFN-γ (IQR: -0.01 IU/mL to 0.01 IU/mL), while the post-vaccination samples contained 0.61 IU/mL IFN-γ (IQR: 0.26-1.32 IU/mL) (p < 0.001). These results were indicative of anti-SARS-CoV-2 Th1 memory responses acquired by vaccination. In 27 of the 28 randomly selected vaccinees, post-vaccination anti-SARS-CoV-2 memory T cell responses were determined using flow cytometry analyses. The percentages of CD3 + CD4 + CD134 + CD137 + cells, representing activated CD4 + T cell subsets, and the percentages of CD3 + CD8 + CD169 + CD137 + cells, representing activated CD8 + T cell subsets, increased in short-term whole blood culture after Ag 1 or Ag 2 stimulation for IGRAs (Fig. 2, Fig. E1 ). In addition, these percentages were strongly correlated with the IFN-γ levels in QuantiFERON SARS-CoV-2 assays (Fig. 3) , indicating the usability of the QuantiFERON SARS-CoV-2 assay. A significant correlation of the percentages of activated T cells with the antibody titers or with the vaccinee age was not observed (Fig. E2 ). All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint The IFN-γ levels in the supernatant of short-term whole blood culture after Ag 1 or Ag 2 stimulation demonstrated a weak positive correlation with antibody titers (IFN-γ levels upon Ag 1 stimulation versus antibody titers; r s = 0.1863, p < 0.001; IFN-γ levels upon Ag 2 stimulation versus antibody titers; r s = 0.1687, p < 0.001) (Fig. 4) . Individuals with a history of pre-vaccination COVID-19 presented higher IFN-γ levels resulting from Ag 1 stimulation than those without the history. IFN-γ level was 0.8 IU/mL (IQR 0.41-2.48 IU/mL) in individuals with a history of COVID-19 and 0.34 IU/mL IFN-γ (IQR 0.14-0.7925 IU/mL, p = 0.046) in those without a history of COVID-19. The IFN-γ levels resulting from Ag 2 stimulation also tended to be higher in individuals with history of the disease than in those without the history, although the difference was not significant (p = 0.051). Vaccinees experiencing adverse reactions after the second vaccine dose (irrespective of symptom types) presented higher IFN-γ levels resulting from Ag 2 stimulation. The IFN-γ levels in vaccinees with adverse reactions after the second dose was 0.63 IU/mL (IQR, 0.27-1.42 IU/mL), while that in vaccinees without adverse reactions after the second dose was 0.53 IU/mL (IQR 0.19-1.11 IU/mL (p = 0.026). A All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 0 similar tendency was observed with IFN-γ levels resulting from Ag 1 stimulation, albeit without statistical significance (p = 0.065). Fever, general fatigue, and local reactions were correlated with higher IFN-γ production upon Ag 1 and Ag 2 stimulation; these correlations were significant ( Table 2 ). The ANCOVA model demonstrated that history of vaccination before developing COVID-19 and adverse reactions after the second dose were independently related to higher IFN-γ production upon Ag 1 and Ag 2 stimulation. In contrast, age, sex, obesity, or adverse reactions after the first dose were not correlated with higher IFN-γ levels (Table 3 ). IGRAs based on short-term whole blood culture, such as QuantiFERON SARS-CoV-2, can be used to measure the extent of helper T cell (Th)1 responsiveness to memory T cells and evaluate cellular immunity. The advantage of the test is that unlike ELISpot and flow cytometry, a large number of samples can be handled simultaneously. To our knowledge, this study is the first to demonstrate a correlation between QuantiFERON SARS-CoV-2 assay and flow cytometry data, supporting the usability of such IGRAs. Our results obtained using a large number of vaccinee samples were consistent with the All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 1 results of previous studies obtained using small number of samples, proving that QuantiFERON SARS-CoV-2 can be used for assessing herd immunity [3-7]. Humoral responses depend on Th responses, which include not only Th1 but also other Th responses, such as those of Th2 and follicular helper T (Tfh) cells. Antigen-specific IFN-γ production mainly represents Th1 responses. Different Th responses do not exert synergistic effects on antibody production [19] . Rather, Th2 responses antagonize Th1 responses. Thus, the contribution of other Th responses to humoral responses might result in significant but weak correlations between the IgG titers and IFN-γ levels. Recently, a multicenter observational study using the anti-RBD IgG titer assay and the QuantiFERON SARS-CoV-2 assay, as used in the present study, involving 543 patients on hemodialysis and 75 healthy volunteers, has been reported by Van Praet et al. [18] . In that study, the Spearman correlation coefficients between antibody titers and IFN-γ levels in patients on hemodialysis and in healthy volunteers were 0.57 and 0.44, respectively, which were stronger than the correlations observed in the present study. The large difference in sample numbers between our study and that of Van Praet et al. might have contributed to the discrepancy in results obtained with the healthy volunteers, while some differences in the quality of immune responses of the All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Observations from a small number of vaccinees who had developed COVID-19 prior to receiving vaccination in the present study indicated that vaccination after SARS-CoV-2 infection enhanced acquisition of cellular immunity, as has been reported previously regarding humoral immunity [20] . Thus, vaccination possibly do not support this observation [21, 22] . In the present study, the antigen-specific IFN-γ production levels were associated with adverse reactions after the second dose but not after the first dose. While the absence of adverse reactions should not be believed to predict failure to acquire immunity in vaccinees, it is plausible that humoral and cellular responses acquired by the first vaccination contributed to the occurrence of some adverse reactions following the second vaccination. All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Currently, the necessity of additional vaccination is being decided mainly based on antibody titers. However, not only antibodies, but also memory B and T cells, participate in immune memory responses. In a previous report, the cut-off value of QuantiFERON SARS-CoV-2 was determined using results of healthy controls before (considered negative) and after vaccination (considered positive) [16] . While this cut-off value may assist in distinguishing between the absence and presence of cellular immunity, it cannot be used for assessing whether vaccination is sufficient for preventing SARS-CoV-2 infection. From the practical perspective, determination of the IFN-γ level in IGRAs for determining whether additional vaccination is required is critical for better infection control. To address this concern, correlations between IFN-γ levels and occurrence of breakthrough infection and comparison of IFN-γ levels between patients with severe and non-severe disease post-vaccination might be helpful. Ag 1 is a mixture of 13-mer peptides restricted to HLA class II, which activates CD4 + , but not CD8 + , T cells. In contrast, Ag 2 is a mixture of 8-and 13-mer peptides restricted to HLA class I and class II, respectively, that activates both CD8 + and CD4 + T cells. In the present study, the frequency of activated CD8 + T cells increased even upon Ag 1 stimulation, while the IFN-γ levels induced upon Ag 2 stimulation were expectedly higher than those induced upon Ag 1 stimulation. This suggests that All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. cross-presentation of some peptides derived from Ag 1 by antigen-presenting cells might occur unexpectedly, resulting in activation of CD8 + T cells. There are also two possibilities of alternative manners other than classical cross-presentation. One is that some 13-mer peptides may be presented by direct binding to HLA class I despite being longer than the suitable length [23] . Another possibility is that non-canonical antigen trimming by intracellular aminopeptidases may occur to activate CD8+ T cells in the HLA class I-restricted manner [24] . Thus, it is plausible that IFN-γ release upon Ag 1 stimulation is caused not only by CD4 + T cells but also by CD8 + T cells. Although CD4 + T cell responses in patients on hemodialysis and healthy volunteers undergoing vaccination were assessed using Ag 1 stimulation in a recent study, the present study demonstrated that distinction between CD4 + and CD8 + T cell responses using Ag 1 and Ag 2 is challenging [17] . This observation cannot be obtained from studies using IGRA alone. Interestingly, flow cytometry analyses in the present study revealed potential cross-presentation of peptides designed to activate CD4 + T cells to CD8 + T cells, which occurs during short-term whole blood culture (Fig. 2, Fig. E1 ). We noticed that a strong T cell responses with Ag1 and Ag2 were observed part of vaccinees with low antibody titer (Fig.4) . This consists with reports showing a All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 5 strong prevention of severe disease by vaccination by a robust T cell immunity even if antibody response was low [25, 26] . In conclusion, IGRAs based on short-term whole blood culture revealed cellular immunity acquired by COVID-19 vaccination in a large number of individuals, providing insights regarding the effects and adverse reactions of vaccination. Our findings showed that IGRAs based on short-term whole blood culture can be used for assessing herd immunity against SARS-CoV-2. This is a part of a long-term observational study of vaccinated Japanese cohorts. From preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Pfizer, New York, USA) started on March 5th, 2021. The second vaccine dose was administered 3 weeks after the first dose. For this study, two serial samples collected from 593 participants selected according to inclusion criteria were used. Pre-vaccination samples were collected before or on the same day of receiving the first dose of the vaccine. The post-vaccination samples were collected at approximately 8 weeks after receiving the second dose. Before collecting pre-vaccination samples, a questionnaire was provided to all All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 7 Immediately after sample collection, serum IgG titers against SARS-CoV-2 spike (S) protein S1 subunit receptor-binding domain (RBD) were measured using Alinity SARS-CoV-2 IgG II Quant reagents (Abbott Laboratories, Illinois, USA) and Alinity i Analyzer i (Abbott Laboratories, Illinois, USA) according to the manufacturer's instructions. The QuantiFERON SARS-CoV-2 RUO assay kit (QFN) (Qiagen, Hilden, Germany) was used for the IGRA based on short-term whole blood culture. In this assay, two types of SARS-CoV-2 S peptides were pooled to stimulate T cells as antigens, namely Ag 1 and Ag 2. Whole blood samples collected in lithium heparin tubes were transferred to four QuantiFERON tubes coated with Ag 1, Ag 2, and mitogen (phytohemagglutinin) as positive controls and non-peptide substances as negative controls, respectively. After incubation at 37°C for 16−24 h, the cultured whole blood samples were processed according to the protocol mentioned by the manufacturer. In brief, the supernatants were collected, except for the samples from 28 vaccinees, samples from whom were subjected to flow cytometry analysis. The cultured whole All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 8 blood samples from these 28 randomly selected vaccinees were transferred to other tubes to separate and collect both cells and supernatants via centrifugation. The supernatants were subjected to ELISAs for measuring IFN-γ concentrations, which were performed using the AP-96 auto microplate EIA reader (Kyowa Medex, Tokyo, Japan) under optimal conditions for the QuantiFERON SARS-CoV-2 ELISA kit (Qiagen, Hilden, Germany). Cells separated from the short-term whole blood culture of 28 randomly selected vaccinees were subjected to flow cytometry assays for detecting T cell activation. After immunostaining with fluorochrome-conjugated antibodies, hemolysis with ammonium chloride, and washing with buffers, the cells were analyzed in a BD FACSLyric cytometer (Becton and Dickinson, CA, USA). The fluorochrome-conjugated antibodies used for immunostaining included CD3 (LEU-4) FITC, CD4 APC-H7, CD8 PerCP-Cy5.5, CD69 PE, CD134 PE-Cy7, and CD137 APC (BD Biosciences, CA, USA). Flow cytometry data were analyzed using the BD FACSuite software (Becton and Dickinson). Activated CD4 + T cells were defined as CD3 + CD4 + CD134 + CD137 + All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 1 9 cells, while activated CD8 + T cells were defined as CD3 + CD8 + CD169 + CD137 + cells [27, 28] . The statistical data of the participants were generated using frequencies and proportions for categorical values and the median and IQR for continuous variables. Fisher's exact test was used for categorical values and the Mann-Whitney U test was used for continuous variables. The IFN-γ levels of culture supernatants derived from Ag 1 and Ag 2 tubes were corrected by subtracting the values measured in negative controls. These corrected IFN-γ levels for Ag 1 or Ag2 were compared between pre-and postvaccination samples. In addition, the correlation between IFN-γ levels and antibody titers was examined. To identify factors affecting cellular immunity, IFN-γ levels for Ag 1 and Ag 2 after vaccination were compared according to patient characteristics, including sex, age (grouped into two groups according to median age of all the participants), body mass index (BMI) (grouped into two groups; BMI ≤ 25 kg/m 2 as thin/normal and BMI > 25 kg/m 2 as obese), medication (systemic steroids or other immunosuppressants), and history of malignancy, autoimmune diseases, and COVID-19. To investigate whether All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Regarding flow cytometric analysis, the percentages of CD3 + CD4 + CD134 + CD137 + phenotypic cells for Ag 1, Ag 2, and positive controls were corrected by subtracting the percentages for negative controls. The percentages of CD3 + CD8 + CD69 + CD137 + cells for Ag 1, Ag 2, and positive controls were corrected similarly. Data obtained from flow cytometric analysis and IGRA were compared using the Wilcoxon matched-pair signed-ranks test. All the statistical analyses were performed using JMP version 15 (SAS Institute, North Carolina, USA). Two-sided p-values less than 0.05 were considered statistically significant. All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The data that support the findings of the present study are available from the corresponding author upon reasonable request. A part of the QuantiFERON SARS-CoV-2 reagents were sponsored by Qiagen K.K.-Japan (Tokyo, Japan). The study design was approved by the Ethics Committee of Keio University School of Medicine (20200330). All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 2 2 Written informed patient consent was obtained before the study. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 4 1 dose Ag 1, Antigen 1; Ag 2, Antigen 2; AR, Adverse reaction All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint Immunogenicity of COVID-19 tozinameran vaccination in patients on chronic dialysis Evaluation of the QuantiFERON SARS-CoV-2 interferon-γ release assay in mRNA-1273 vaccinated health care workers preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this this version posted The ROMANOV study found impaired humoral and cellular immune responses to SARS-CoV-2 mRNA vaccine in virus-unexposed patients receiving maintenance hemodialysis Predictors and dynamics of the humoral and cellular immune response to SARS-CoV-2 mRNA vaccines in hemodialysis patients: a multicenter observational study All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Longitudinal analysis of human memory T-cell response according to the severity of All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint 3 4 BMI; Body Mass Index, IQR; Interquartile range All rights reserved. No reuse allowed without permission. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this this version posted December 15, 2021. ; https://doi.org/10.1101/2021.12.14.21267039 doi: medRxiv preprint