(C) Association between RBD-IgG antibody titers and mycophenolate mofetil dose in liver transplant recipients by restricted cubic spline magic size with four knots. below the detection limit are plotted as 0.1?AU/mL. (C) Association between RBD-IgG antibody titers and mycophenolate mofetil dose in liver transplant recipients by restricted cubic spline model with four knots. The shaded area represents the 95% confidence interval. IQR, interquartile range; RBD, S receptor-binding website. The overall seroconversion rate after the second vaccination was 86.7% in study participants. Liver transplant recipients showed a lower seroconversion rate (44/56; 78.6%) than healthy settings (41/42; 97.6%). The seroconversion rate was reduced recipients taking mycophenolate mofetil (21/33, 63.6%) than in those not taking mycophenolate mofetil Diosmetin-7-O-beta-D-glucopyranoside (23/23, 100%; = 0.001), whereas the seroconversion rate was higher in recipients taking calcineurin inhibitor (42/51, 82.4%) than in those not taking calcineurin inhibitor (2/5, 40.0%; = 0.06). Number 1B compares antibody titers between liver transplant recipients with or without use of mycophenolate mofetil. Development of RBD IgG antibody titers was less likely in liver transplant recipients taking mycophenolate mofetil (median, 2.9?AU/mL; IQR, 0.20C13.0?AU/mL) than in those not Diosmetin-7-O-beta-D-glucopyranoside taking mycophenolate mofetil (median, 20.0?AU/mL; IQR, 10.5C20.0?AU/mL; 0.001). A restricted cubic spline storyline (Number 1C) shows the relationship between RBD IgG antibody titers and total mycophenolate mofetil dose in liver Rabbit Polyclonal to MLK1/2 (phospho-Thr312/266) transplant recipients. An inverse linear relationship between RBD IgG antibody titers and mycophenolate mofetil dose was recognized (for effect = 0.008, for non-linearity = 0.24). Our findings in liver transplant recipients confirmed suboptimal immunogenicity after the second dose of BNT162b2 vaccine, assisting findings from additional studies of kidney transplant recipients (3), allogeneic hematopoietic stem-cell transplant recipients (6) and lung transplant recipients (7). Concern remains about the event of severe COVID-19 in some vaccinated immunocompromised transplant recipients. The seroconversion rate was as low as 63.6% (21/33) in individuals taking mycophenolate mofetil. Actually in individuals with confirmed seroconversion, antibody levels were low, suggesting the threshold for protecting immunity had not been reached. Restricted cubic spline modeling also verified a linear dose-response relationship between mycophenolate mofetil dose and reduced antibody titers in our study. Reduced antibody reactions among organ transplant recipients, including liver transplant recipients, suggest that these recipients may remain at high risk of COVID-19 actually after the second and third doses of mRNA vaccine. Our findings have medical implications for liver transplant recipients, emphasizing the need to consider a fourth dose of vaccination and the assessment of antibody titers actually after the third dose of vaccination. Although a third vaccine dose was well tolerated by solid organ transplant recipients who experienced an insufficient antibody response after two dose of vaccination, the serological response was heterogeneous and a large proportion of recipients remain at Diosmetin-7-O-beta-D-glucopyranoside risk for COVID-19 (8, 9). Approaches to improve antibody reactions in transplant recipients may require temporary reduction or withdrawal of mycophenolate mofetil, or alternative to additional immunosuppressants and additional measures such as subsequent a fourth dose of vaccination (10). The assessment of antibody titers actually after the third dose of Diosmetin-7-O-beta-D-glucopyranoside vaccination might be important to discriminate individuals who should maintain their barrier measures. Longevity of the antibody titer and the optimal period of monitoring antibody titers are still unveiled. Further longitudinal studies are Diosmetin-7-O-beta-D-glucopyranoside warranted to investigate how cellular immune reactions will be managed or whether waning antibody titers still provide protection from breakthrough infections in transplant recipients with.