Additional file 4 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 4: Supplementary Table 3.Thymic activity, Biochemical, Inflammatory and Immunological profiles of the study populations one month after the second dose (T1).Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 7 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 7: Supplementary Fig. 4. Factors associated with the magnitude of the initial response to the BNT162B2 vaccine at T1 by age-groups.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 1 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 1: Supplementary Fig. 1. Study design and Flow-chart.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.[Background] Older people achieve lower levels of antibody titers than younger populations after Covid-19 vaccination and show a marked waning humoral immunity over time, likely due to the senescence of the immune system. Nevertheless, age-related predictive factors of the waning humoral immune response to the vaccine have been scarcely explored. In a cohort of residents and healthcare workers from a nursing home that had received two doses of the BNT162b2 vaccine, we measured specific anti-S antibodies one (T1), four (T4), and eight (T8) months after receiving the second dose. Thymic-related functional markers, including thymic output, relative telomere length, and plasma thymosin-α1 levels, as well as immune cellular subsets, and biochemical and inflammatory biomarkers, were determined at T1, and tested for their associations with the magnitude of the vaccine response (T1) and the durability of such response both, at the short- (T1-T4) and the long-term (T1-T8). We aimed to identify age-related factors potentially associated with the magnitude and persistence of specific anti-S immunoglobulin G (IgG)-antibodies after COVID-19 vaccination in older people.[Results] Participants (100% men, n = 98), were subdivided into three groups: young (< 50 years-old), middle-age (50–65 years-old), and older (≥65 years-old). Older participants achieved lower antibody titers at T1 and experienced higher decreases in both the short- and long-term. In the entire cohort, while the magnitude of the initial response was mainly associated with the levels of homocysteine [β (95% CI); − 0.155 (− 0.241 to − 0.068); p = 0.001], the durability of such response at both, the short-term and the long-term were predicted by the levels of thymosin-α1 [− 0.168 (− 0.305 to − 0.031); p = 0.017, and − 0.123 (− 0.212 to − 0.034); p = 0.008, respectively].[Conclusions] Higher plasma levels of thymosin-α1 were associated with a lower waning of anti-S IgG antibodies along the time. Our results suggest that plasma levels of thymosin-α1 could be used as a biomarker for predicting the durability of the responses after COVID-19 vaccination, possibly allowing to personalize the administration of vaccine boosters.This work was supported by the Instituto de Salud Carlos III through the project “PI21/00357” (Co-funded by European Regional Development Fund/European Social Fund “A way to make Europe”/“Investing in your future”). MMPB was supported by a postdoctoral contract from Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía (DOC_01646). ABR, IOM and VGR were supported by Instituto de Salud Carlos III (Sara Borrell program CD19/00143, Río Hortega program CM19/00051, and PFIS program FI19/00298, respectively). YMP was supported by the Consejería de Salud y Familias of Junta de Andalucía through the “Nicolás Monardes” program (RC-0006-2021).Peer reviewe

Additional file 6 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 6: Supplementary Fig. 3. Correlations among Log of anti-S antibody titers at all different study points.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 8 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 8. Detailed methodology.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 2 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 2: Supplementary Table 1. Demographical and anthropometrics characteristics of the study population.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 5 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 5: Supplementary Fig. 2. Levels of Thymosin-α1 in higher vs. lower responders of the older group.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Additional file 3 of Higher plasma levels of thymosin-α1 are associated with a lower waning of humoral response after COVID-19 vaccination: an eight months follow-up study in a nursing home

Additional file 3: Supplementary Table 2. Comorbidities and behavioral factors of residents from the Santa Caridad Nursing Home.Consejería de Transformación Económica, Industria, Conocimiento y Universidades Instituto de Salud Carlos III Consejería de Salud y Familias, Junta de AndalucíaPeer reviewe

Factors associated with the humoral response after three doses of COVID-19 vaccination in kidney transplant recipients

[Introduction] Kidney transplant recipients showed a weak humoral response to the mRNA COVID-19 vaccine despite receiving three cumulative doses of the vaccine. New approaches are still needed to raise protective immunity conferred by the vaccine administration within this group of high-risk patients.[Methods] To analyze the humoral response and identify any predictive factors within these patients, we designed a prospective monocentric longitudinal study of Kidney transplant recipients (KTR) who received three doses of mRNA-1273 COVID-19 vaccine. Specific antibody levels were measured by chemiluminescence. Parameters related to clinical status such as kidney function, immunosuppressive therapy, inflammatory status and thymic function were analyzed as potential predictors of the humoral response.[Results] Seventy-four KTR and sixteen healthy controls were included. One month after the administration of the third dose of the COVID-19 vaccine, 64.8% of KTR showed a positive humoral response. As predictive factors of seroconversion and specific antibody titer, we found that immunosuppressive therapy, worse kidney function, higher inflammatory status and age were related to a lower response in KTR while immune cell counts, thymosin-a1 plasma concentration and thymic output were related to a higher humoral response. Furthermore, baseline thymosin-a1 concentration was independently associated with the seroconversion after three vaccine doses.[Discussion] In addition to the immunosuppression therapy, condition of kidney function and age before vaccination, specific immune factors could also be relevant in light of optimization of the COVID-19 vaccination protocol in KTR. Therefore, thymosin-a1, an immunomodulatory hormone, deserves further research as a potential adjuvant for the next vaccine boosters.This study was supported by a grant from the Fondo de Investigación Sanitaria (FIS/PI21/00357), which is co-founded by Fondos Europeos para el Desarrollo Regional (FEDER) “Una manera de hacer Europa”. VG-R, IO-M and AB-R were supported by Instituto de Salud Carlos III (CD19/00143, FI19/00298 and CM19/00051, respectively). MP-B was supported by the Consejería de Transformación Económica, Industria, Conocimiento y Universidades [DOC_01646 to MP-B] and YP was supported by the Consejería de Salud y Familias of Junta de Andalucía through the “Nicolás Monardes” [RC-0006-2021].Peer reviewe