biostudies-literatureBenning LDietmar Hopp Stiftung98-106https://www.ebi.ac.uk/biostudies/studies/S-EPMC8763153biostudies-literatureUnknown17(1)<h4>Background and objectives</h4>Antibody response after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is impaired in kidney transplant recipients. Emerging variants, such as B.1.617.2 (<i>δ</i>), are of particular concern because of their higher transmissibility and partial immune escape. Little is known about protection against these variants in immunocompromised patients.<h4>Design, setting, participants, & measurements</h4>In this prospective two-center study, antispike 1 IgG and surrogate neutralizing antibodies were measured in 173 kidney transplant recipients and 166 healthy controls with different vaccination schedules. In addition, different SARS-CoV-2 epitope antibodies from 135 vaccinated kidney transplant recipients were compared with antibodies in 25 matched healthy controls after second vaccination. In 36 kidney transplant recipients with seroconversion, neutralization against B.1.1.7 (<i>α</i>), B.1.351 (<i>β</i>), and B.1.617.2 (<i>δ</i>) was determined on VeroE6 cells and compared with neutralization in 25 healthy controls.<h4>Results</h4>Kidney transplant recipients had significantly lower seroconversion rates compared with healthy controls. After the second vaccination, antispike 1, antireceptor-binding domain, and surrogate neutralizing antibodies were detectable in 30%, 27%, and 24% of kidney transplant recipients, respectively. This compares with 100%, 96%, and 100% in healthy controls, respectively (<i>P</i><0.001). Neutralization against B.1.1.7 was detectable in all kidney transplant recipients with seroconversion, with a median serum dilution that reduces infection of cells by 50% of 80 (interquartile range, 80-320). In contrast, only 23 of 36 (64%) and 24 of 36 (67%) kidney transplant recipients showed neutralization against B.1.351 and B.1.617.2, respectively, with median serum dilutions that reduce infection of cells by 50% of 20 (interquartile range, 0-40) and 20 (interquartile range, 0-40), respectively. Neutralization against different variants was significantly higher in healthy controls (<i>P</i><0.001), with all patients showing neutralization against all tested variants.<h4>Conclusions</h4>Seroconverted kidney transplant recipients show impaired neutralization against emerging variants of concern after standard two-dose vaccination.<h4>Clinical trial registry name and registration number</h4>Observational study to assess the SARS-CoV-2 specific immune response in kidney transplant recipients (COVID-19 related immune response), DRKS00024668.Clinical journal of the American Society of Nephrology : CJASNNeutralization of SARS-CoV-2 Variants of Concern in Kidney Transplant Recipients after Standard COVID-19 Vaccination.PMC87631531DH2111111Hidmark AMorath CKlein KTollner MBartenschlager RSusal CBenning LBartenschlager MSchaier MReineke MGrenz JBuylaert MSchnitzler PBeimler JZeier MRieger SSpeer CReichel PKalble FNusshag CPonath GTonshoff BfalseNeutralization of SARS-CoV-2 Variants of Concern in Kidney Transplant Recipients after Standard COVID-19 Vaccination.<h4>Background and objectives</h4>Antibody response after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is impaired in kidney transplant recipients. Emerging variants, such as B.1.617.2 (<i>δ</i>), are of particular concern because of their higher transmissibility and partial immune escape. Little is known about protection against these variants in immunocompromised patients.<h4>Design, setting, participants, & measurements</h4>In this prospective two-center study, antispike 1 IgG and surrogate neutralizing antibodies were measured in 173 kidney transplant recipients and 166 healthy controls with different vaccination schedules. In addition, different SARS-CoV-2 epitope antibodies from 135 vaccinated kidney transplant recipients were compared with antibodies in 25 matched healthy controls after second vaccination. In 36 kidney transplant recipients with seroconversion, neutralization against B.1.1.7 (<i>α</i>), B.1.351 (<i>β</i>), and B.1.617.2 (<i>δ</i>) was determined on VeroE6 cells and compared with neutralization in 25 healthy controls.<h4>Results</h4>Kidney transplant recipients had significantly lower seroconversion rates compared with healthy controls. After the second vaccination, antispike 1, antireceptor-binding domain, and surrogate neutralizing antibodies were detectable in 30%, 27%, and 24% of kidney transplant recipients, respectively. This compares with 100%, 96%, and 100% in healthy controls, respectively (<i>P</i><0.001). Neutralization against B.1.1.7 was detectable in all kidney transplant recipients with seroconversion, with a median serum dilution that reduces infection of cells by 50% of 80 (interquartile range, 80-320). In contrast, only 23 of 36 (64%) and 24 of 36 (67%) kidney transplant recipients showed neutralization against B.1.351 and B.1.617.2, respectively, with median serum dilutions that reduce infection of cells by 50% of 20 (interquartile range, 0-40) and 20 (interquartile range, 0-40), respectively. Neutralization against different variants was significantly higher in healthy controls (<i>P</i><0.001), with all patients showing neutralization against all tested variants.<h4>Conclusions</h4>Seroconverted kidney transplant recipients show impaired neutralization against emerging variants of concern after standard two-dose vaccination.<h4>Clinical trial registry name and registration number</h4>Observational study to assess the SARS-CoV-2 specific immune response in kidney transplant recipients (COVID-19 related immune response), DRKS00024668.2022-01-01T00:00:00Z2022 Jan2025-04-21T15:19:59.442Z2025-04-21T15:19:59.442ZS-EPMC87631533493777110.2215/cjn.1182092110.2215/CJN.11820921