{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T19:44:47Z","timestamp":1768074287856,"version":"3.49.0"},"reference-count":28,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,6,2]],"date-time":"2023-06-02T00:00:00Z","timestamp":1685664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Onassis Cardiac Surgery Center","award":["704\/13.01.2021"],"award-info":[{"award-number":["704\/13.01.2021"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Solid organ transplant (SOT) recipients have a higher risk of suffering from severe Coronavirus (COVID-19) compared to the general population. Studies have shown impaired immunogenicity of mRNA vaccines in this high-risk population; thus, SOT recipients have been prioritized globally for primary and booster doses. Materials and Methods: We analyzed 144 SOT recipients who had previously received two doses of BNT162b2 or mRNA1273 vaccine, and who were subsequently vaccinated with a booster dose of the mRNA1273 vaccine. Humoral and cellular immune responses were measured 1 and 3 months after the second dose, and 1 month after the third dose. Results: One month after the second dose, 33.6% (45\/134) of patients displayed a positive antibody response with a median (25th, 75th) antibody titer of 9 (7, 161) AU\/mL. Three months after the second dose, 41.8% (56\/134) tested positive with a median (25th, 75th) antibody titer of 18 (7, 251) AU\/mL. After the booster dose, the seropositivity rate increased to 69.4% (93\/134), with a median (25th, 75th) titer of 966 (10, 8027) AU\/mL. The specific SARS-CoV-2 T-cell response was assessed in 44 randomly selected recipients 3 months after the second dose, and 11.4% (5\/44) of them had a positive response. Following the third dose, 42% (21\/50) tested positive. Side effects after the third dose were mild, with pain at the injection site being the most frequent adverse effect, reported by 73.4% of the recipients. Conclusion: Our study shows a mild delayed increase in antibody titer, three months after primary vaccination compared to one month after. It also shows a robust augmentation of humoral and specific T-cell responses after the booster dose, as well as the safety and tolerability of the mRNA vaccines in SOT recipients.<\/jats:p>","DOI":"10.3390\/medicina59061075","type":"journal-article","created":{"date-parts":[[2023,6,2]],"date-time":"2023-06-02T08:50:31Z","timestamp":1685695831000},"page":"1075","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Assessment of mRNA Vaccine Immunogenicity in Solid Organ Transplant Recipients"],"prefix":"10.3390","volume":"59","author":[{"given":"Paraskevi","family":"Tsoutsoura","sequence":"first","affiliation":[{"name":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School of Athens, National and Kapodistrian University, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9335-0661","authenticated-orcid":false,"given":"Efstathios","family":"Xagas","sequence":"additional","affiliation":[{"name":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School of Athens, National and Kapodistrian University, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2347-0817","authenticated-orcid":false,"given":"Sotirios","family":"Roussos","sequence":"additional","affiliation":[{"name":"Department of Hygiene, Epidemiology & Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, 15772 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angelos","family":"Hatzakis","sequence":"additional","affiliation":[{"name":"Department of Hygiene, Epidemiology & Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, 15772 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Polyxeni","family":"Gourzi","sequence":"additional","affiliation":[{"name":"Molecular Immunopathology and Histocompatibility Unit, Onassis Cardiac Surgery Center, 17674 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ioannis N.","family":"Boletis","sequence":"additional","affiliation":[{"name":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School of Athens, National and Kapodistrian University, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Smaragdi","family":"Marinaki","sequence":"additional","affiliation":[{"name":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School of Athens, National and Kapodistrian University, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,2]]},"reference":[{"key":"ref_1","unstructured":"WHO (2022, December 19). WHO Coronavirus (COVID-19) Dashboard with Vaccination Data. Available online: https:\/\/covid19.who.int\/."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"100628","DOI":"10.1016\/j.trre.2021.100628","article-title":"The association between severe or death COVID-19 and solid organ transplantation: A systematic review and meta-analysis","volume":"35","author":"Ao","year":"2021","journal-title":"Transplant. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Marinaki, S., Tsiakas, S., Korogiannou, M., Grigorakos, K., Papalois, V., and Boletis, I. (2020). A Systematic Review of COVID-19 Infection in Kidney Transplant Recipients: A Universal Effort to Preserve Patients\u2019 Lives and Allografts. J. Clin. Med., 9.","DOI":"10.3390\/jcm9092986"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2913","DOI":"10.1111\/ajt.16607","article-title":"Immunogenicity of SARS-CoV-2 BNT162b2 vaccine in solid organ transplant recipients","volume":"21","author":"Marinaki","year":"2021","journal-title":"Am. J. Transplant."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1093\/cid\/ciq104","article-title":"Humoral response to the influenza A H1N1\/09 monovalent AS03-adjuvanted vaccine in immunocompromised patients","volume":"52","author":"Manuel","year":"2011","journal-title":"Clin. Infect. Dis."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Eckerle, I., Rosenberger, K.D., Zwahlen, M., and Junghanss, T. (2013). Serologic vaccination response after solid organ transplantation: A systematic review. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0056974"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"13926","DOI":"10.1111\/tid.13926","article-title":"Humoral and cellular response of COVID-19 vaccine among solid organ transplant recipients: A systematic review and meta-analysis","volume":"24","author":"Meshram","year":"2022","journal-title":"Transpl. Infect. Dis."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Quiroga, B., Soler, M.J., Ortiz, A., and de Sequera, P. (Nefrolog\u00eda, 2022). Lessons from SENCOVAC: A prospective study evaluating the response to SARS-CoV-2 vaccination in the CKD spectrum, Nefrolog\u00eda, in press.","DOI":"10.1016\/j.nefro.2022.12.006"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1056\/NEJMc2108861","article-title":"Three Doses of an mRNA Covid-19 Vaccine in Solid-Organ Transplant Recipients","volume":"385","author":"Kamar","year":"2021","journal-title":"N. Engl. J. Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"E267","DOI":"10.1097\/TP.0000000000003903","article-title":"Cellular and Humoral Immune Responses after 3 Doses of BNT162b2 mRNA SARS-CoV-2 Vaccine in Kidney Transplant","volume":"105","author":"Stumpf","year":"2021","journal-title":"Transplantation"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1001\/jamainternmed.2021.7372","article-title":"Comparison of SARS-CoV-2 Antibody Response 4 Weeks after Homologous vs Heterologous Third Vaccine Dose in Kidney Transplant Recipients: A Randomized Clinical Trial","volume":"182","author":"Heinzel","year":"2022","journal-title":"JAMA Intern. Med."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Marinaki, S., Degiannis, D., Roussos, S., Xagas, E., Tsoutsoura, P., Adamopoulos, S., Sypsa, V., Chaidaroglou, A., Pavlopoulou, I.D., and Hatzakis, A. (2022). Head-to-Head Comparison of Response Rates to the Two mRNA SARS-C\u03bfV-2 Vaccines in a Large Cohort of Solid Organ Transplant (SOT) Recipients. Vaccines, 10.","DOI":"10.3390\/vaccines10020190"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1405","DOI":"10.1093\/clinchem\/hvaa198","article-title":"Side-by-Side Comparison of Three Fully Automated SARS-CoV-2 Antibody Assays with a Focus on Specificity","volume":"66","author":"Perkmann","year":"2020","journal-title":"Clin. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"e84","DOI":"10.1056\/NEJMoa2114583","article-title":"Waning Immune Humoral Response to BNT162b2 COVID-19 Vaccine over 6 Months","volume":"385","author":"Levin","year":"2021","journal-title":"N. Engl. J. Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2105611","DOI":"10.1080\/21645515.2022.2105611","article-title":"Correlation between anti-S IgG and neutralizing antibody titers against three live SARS-CoV-2 variants in BNT162b2 vaccine recipients","volume":"18","author":"Higashimoto","year":"2022","journal-title":"Hum. Vaccines Immunother."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1093\/infdis\/jiaa273","article-title":"Sensitivity in Detection of Antibodies to Nucleocapsid and Spike Proteins of Severe Acute Respiratory Syndrome Coronavirus 2 in Patients with Coronavirus Disease 2019","volume":"222","author":"Burbelo","year":"2020","journal-title":"J. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"E109","DOI":"10.1097\/TP.0000000000003975","article-title":"Six-month Antibody Kinetics and Durability in SARS-CoV-2 mRNA Vaccinated Solid Organ Transplant Recipients","volume":"106","author":"Alejo","year":"2022","journal-title":"Transplantation"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Sakuraba, A., Luna, A., and Micic, D. (2022). A Systematic Review and Meta-Analysis of Serologic Response following Coronavirus Disease 2019 (COVID-19) Vaccination in Solid Organ Transplant Recipients. Viruses, 14.","DOI":"10.3390\/v14081822"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Osmanodja, B., Ronicke, S., Budde, K., Jens, A., Hammett, C., Koch, N., Seelow, E., Waiser, J., Zukunft, B., and Bachmann, F. (2022). Serological Response to Three, Four and Five Doses of SARS-CoV-2 Vaccine in Kidney Transplant Recipients. J. Clin. Med., 11.","DOI":"10.1101\/2022.03.23.22270017"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2089","DOI":"10.1111\/ajt.17020","article-title":"Neutralization against Omicron variant in transplant recipients after three doses of mRNA vaccine","volume":"22","author":"Kumar","year":"2022","journal-title":"Am. J. Transplant."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1007\/s10096-022-04422-7","article-title":"Performance comparison of a flow cytometry immunoassay for intracellular cytokine staining and the QuantiFERON\u00ae SARS-CoV-2 test for detection and quantification of SARS-CoV-2-Spike-reactive-IFN-\u03b3-producing T cells after COVID-19 vaccination","volume":"41","author":"Tormo","year":"2022","journal-title":"Eur. J. Clin. Microbiol. Infect. Dis."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.healun.2021.08.010","article-title":"Third dose of the BNT162b2 vaccine in heart transplant recipients: Immunogenicity and clinical experience","volume":"41","author":"Peled","year":"2022","journal-title":"J. Heart Lung Transplant."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3170","DOI":"10.3389\/fimmu.2022.904686","article-title":"The Robustness of Cellular Immunity Determines the Fate of SARS-CoV-2 Infection","volume":"13","author":"Moga","year":"2022","journal-title":"Front. Immunol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.cell.2020.08.017","article-title":"Robust T Cell Immunity in Convalescent Individuals with Asymptomatic or Mild COVID-19","volume":"183","author":"Sekine","year":"2020","journal-title":"Cell"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"621","DOI":"10.1146\/annurev-immunol-031210-101400","article-title":"Follicular Helper CD4 T Cells (TFH)","volume":"29","author":"Crotty","year":"2011","journal-title":"Annu. Rev. Immunol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3990","DOI":"10.1111\/ajt.16818","article-title":"Cellular immunity predominates over humoral immunity after homologous and heterologous mRNA and vector-based COVID-19 vaccine regimens in solid organ transplant recipients","volume":"21","author":"Schmidt","year":"2021","journal-title":"Am. J. Transplant."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Korogiannou, M., Vallianou, K., Xagas, E., Rokka, E., Soukouli, I., Boletis, I.N., and Marinaki, S. (2023). Disease Course, Management and Outcomes in Kidney Transplant Recipients with SARS-CoV-2 Infection during the Omicron-Variant Wave: A Single-Center Experience. Vaccines, 11.","DOI":"10.3390\/vaccines11030632"},{"key":"ref_28","unstructured":"(2022, December 29). Joint Statement about COVID-19 Vaccination in Organ Transplant Candidates and Recipients|American Society of Transplantation. Available online: https:\/\/www.myast.org\/joint-statement-about-covid-19-vaccination-organ-transplant-candidates-and-recipients-0."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/59\/6\/1075\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:47:58Z","timestamp":1760125678000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/59\/6\/1075"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,6,2]]},"references-count":28,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2023,6]]}},"alternative-id":["medicina59061075"],"URL":"https:\/\/doi.org\/10.3390\/medicina59061075","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,6,2]]}}}