ABSTRACT
Background: There is still a lack of knowledge on host immune response and risk of reinfection, particularly in special groups, such as liver transplant recipients. Immunosuppressive agents are known to interfere with T- and/or B-lymphocytes, which are required to mount an adequate serologic response. Therefore, we aim to investigate the antibody response to SARS-CoV-2 in liver transplant (LT) recipients after COVID-19. Methods: We conducted a prospective multicenter casecontrol study analyzing antibodies against the nucleocapsidprotein and spike protein of SARS-CoV-2 in LT recipients with confirmed SARS-CoV-2 infection (COVID-LT) compared to immunocompetent patients (COVID-immunocompetent) and liver transplant patients without COVID-19 symptoms (non-COVID LT). Serum samples were collected from all the participants included in the study. In the COVID-LT cohort, as well as in the COVID-immunocompetent cohort, the samples were drawn between 4-8 weeks after the detection of the SARS-CoV-2 infection. Results: Overall, 35 LT recipients were included in the COVID-LT cohort. Male gender was most prevalent (25 recipients, 71.4%) and mean age was 56.7±13.9 years. 35 and 70 subjects fulfilling the matching criteria were assigned to the COVID-immunocompetent and non-COVID LT cohort, respectively. We showed that LT recipients, despite the use of immunosuppressive drugs and less symptoms, mounted a detectable anti-nucleocapsid antibody titer in 80% of the cases, although the level was significantly lower in comparison to the level detected in the COVID-immunocompetent cohort (3.73 vs. 7.36, p<0.001). When analyzing the anti-spike-protein antibody response, no difference in positivity rates was found between the COVIDLT and the COVID-immunocompetent cohorts (97.1% vs. 100%, p=0.314). Considering the non-COVID LT group, we found that cross-reactivity with other coronavirus species is irrelevant for these assays (only one positivity for the antinucleocapsid and two for the anti-spike). Conclusion: Our findings suggest that the humoral response of LT recipients is only slightly lower than expected compared with that of COVID-19 immunocompetent controls. Anti-nucleocapsid antibodies, although specific for SARS-CoV-2 when tested alone, may erroneously lead to an underestimation of the immune response in this population. Testing for anti-spike antibodies adds sensitivity. Altogether, routine antibody testing against separate SARS-CoV-2 antigens shows that LT patients are capable of mounting an adequate antibody response against SARS-CoV-2.
ABSTRACT
Since January 2020, the Novel Coronavirus Disease 2019 (COVID-19) pandemic has dramatically impacted the world. In March 2020, the COVID-19 epidemic reached Belgium creating uncertainty towards all aspects of life. There has been an impressive capacity and solidarity of all healthcare professionals to acutely reconvert facilities to treat these patients. In the context of liver transplantation (LTx), concerns are raised about organ donation shortage and safety, the ethics of using limited healthcare resources for LTx, selection criteria for LTx during the epidemic and the risk of de novo COVID-19 infection on the waiting list and after LTx. BeLIAC makes several recommendations to try to mitigate the deleterious effect that this epidemic has/will have on donation and LTx, taking into account the available resources, and trying to maximize patients and healthcare professionals' safety.