Inclusion Criteria:  18≤ age ≤60, 18 kg/m2 ≤BMI ≤28 kg/m2, male or female; Diagnosed with 2019-nCoV infection and classified clinically as mild or general; Agreed not to participate in other clinical studies before completing this study; With the subject's consent and signed informed consent form by the subject or his/her legal representative.  Exclusion Criteria:  Diagnosed with 2019-nCoV infection and classified clinically as severe or critical severe; severe pneumonia or acute respiratory distress syndrome, sepsis and septic shock; The disease would deteriorate significantly within 48 hours judged by the investigators; Immunodeficiency or immune related diseases not suitable for participation judged by the investigators (such as autoimmune diseases, IgG4 related diseases, allergic alveolitis, vasculitis, etc); Lymphocyte count <0.5×109/L; Neutropenia history (neutrophil absolute count was less than 2×109/L in adults), except for infection; D- dimer >2000 µg/L; Severe history of lung diseases, such as chronic obstructive pulmonary disease, lung cancer, tuberculosis, etc., history of heart disease: unstable angina pectoris, myocardial infarction, cardiac surgery, cardiac function≥ grade 3 (NYHA classification), serious history of liver disease (such as Child Pugh score ≥grade C), serious renal disease history, such as renal insufficiency (GFR ≤ 15ml/min/1.73m2), etc;  The subjects used the following drugs within 2 weeks (including 2 weeks) before screening:  Calcineurin inhibitors (such as cyclosporin and tacrolimus); Proliferation inhibitors (such as everolimus, sirolimus, etc); anti-metabolic agents (such as mycophenolate mofetil, mycophenolic acid, purine sulfate, etc); Pregnant or lactating women.