The clinical classification of patients with severe novel coronavirus infection is to meet any of the following: 1) Respiratory failure occurs and requires mechanical ventilation, 2) Shock occurs, 3) Combined failure of other organs requires ICU monitoring and treatment, 2. Those who are allergic to blood products or plasma components and auxiliary materials (sodium citrate), 3. There is multiple organ failure, and the estimated survival time is less than 3 days, 4. Those who tested positive for HIV antibodies before enrollment, 5. Women who are pregnant or breastfeeding or have a birth plan within the past year, 6. Participants in other clinical trials within 1 months before screening, 7.Poor adherence or other conditions that the investigator believes are not suitable for inclusion (such as poor physical condition).

The clinical classification of patients with severe novel coronavirus infection is to meet any of the following: 1) Respiratory failure occurs and requires mechanical ventilation, 2) Shock occurs, 3) Combined failure of other organs requires ICU monitoring and treatment, 2. Those who are allergic to blood products or plasma components and auxiliary materials (sodium citrate), 3. There is multiple organ failure, and the estimated survival time is less than 3 days, 4. Those who tested positive for HIV antibodies before enrollment, 5. Women who are pregnant or breastfeeding or have a birth plan within the past year, 6. Participants in other clinical trials within 1 months before screening, 7.Poor adherence or other conditions that the investigator believes are not suitable for inclusion (such as poor physical condition).