Footnotes

• Handling editor Josef S Smolen

• Contributors All authors made substantial contributions to the conception and design of this study. LS, CL and LL acquired the data. JL and YH performed the data analysis and drafted the manuscript. YZ, XZ and FZ provided critical revisions to the manuscript. WZ designed the study, contributed to the discussion and edited the manuscript. All authors read and approved the final manuscript.

• Funding This work was supported by the National Natural Science Foundation of China (grant number 81871299); CAMS Initiative for Innovative Medicine (grant numbers CIFMS2017-I2M-1-008 and CIFMS2016-I2M-1-013), National Key Research and Development Program: “Precise Medical Research” (grant number 2016YFC0906201).

• Competing interests None declared.

• Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

• Patient consent for publication Not required.

• Ethics approval Institutional review board of Peking Union Medical College Hospital.

• Provenance and peer review Not commissioned; externally peer reviewed.