Peripheral HLA-G/ILT-2 immune checkpoint axis in acute and convalescent COVID-19 patients.

"appendix a supplementary material the following are the supplementary data to this article: supplementary data 1 acknowledgements this work was supported by the "stiftung universitatsmedizin" (approval no 2020 4699 135) university of duisburg-essen and the "rudolf ackermann stiftung"."

"Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper."

"This work was supported by the “Stiftung Universitätsmedizin” (approval no. 2020 4699 135), University of Duisburg-Essen and the “Rudolf Ackermann Stiftung”. Special thanks go to the patients kindly providing their samples. We are grateful for the technical support to the team of the Department of Infectious Diseases and the colleagues from the Institute for Transfusion Medicine, both University Hospital Essen."