ESPN 54th Annual Meeting

ESPN 2022


 
SARS-CoV-2 Antigen-Specific Cellular and Humoral Immune Response after two or three doses mRNA vaccine BNT162b2 in adolescent kidney transplant recipients
CYRIELLE PARMENTIER 1 ISABELLE NEL 2 LAURENE DEHOUX 3 MARINA CHARBIT 3 FERIELLE LOUILLET 4 ELODIE CHEYSSAC 2 JEAN-DANIEL DELBET 1 VERONIQUE BAUDOUIN 2 TIM ULINSKI 1 GUISLAINE CARCELAIN 2 JULIEN HOGAN 2

1- TROUSSEAU HOSPITAL, APHP, PARIS FRANCE
2- ROBERT DEBRE HOSPITAL, APHP, PARIS FRANCE
3- NECKER HOSPITAL, APHP, PARIS, FRANCE
4- ROUEN NORMANDIE, CHU HOSPITAL, ROUEN, FRANCE
 
Introduction:

 Adolescent kidney transplant recipients (KTRs) are immunocompromised and therefore prioritized for SARS-CoV-2 mRNA vaccination. Data are lacking regarding their humoral and cellular response to COVID-19 vaccination.

Material and methods:

 We conducted a retrospective study to analyze the early (between 21 and 90 days) humoral immune (ELISA) or/and cellular (interferon-g release assay and flow cytometry) response in 48 KTRs aged 12 to 21 years, using two or three doses of mRNA vaccine BNT162b2.

Results:

 SARS-CoV-2-vaccination induced seroconversion with a humoral response in 86% patients after 2 doses and 88% after 3 doses. The third dose induced seroconversion in the 3 seronegative patients after two doses. Median antibody levels were 1500 BAU/mL IQ (414; 2860) and 955 (163; 3737) after 2 and 3 doses, respectively. Only 12/28 (43%) patients showed a specific T cell response after the second injection and 11/23 (48%) after a third. Patients with a history of COVID-19 infection received only 2 injections were all responders. KTRs treated with an immunosuppression including mycophenolate were more likely to be non-responders than in those with azathioprine (76% vs. 100%). Likewise, after two doses in KTRs with lymphopenia, 5/7 (71%) patients had no specific T cell response vs. 13/24 (54%) in patients with normal lymphocyte count, and a median specific IgG directed against the spike protein of 261 BAU/mL vs. 1790 BAU/mL (p= 0.02) respectively.

Conclusions:

 Adolescent KTRs exhibit a high seroconversion rate of 86% after only two doses. Immunosuppressive drug type, as well as lymphopenia are determinants of seroconversion failure suggesting the need for immune monitoring and adaptation of vaccination protocols for this specific population.