COVID-19 Research Paper Volume 12, Issue 24 pp 24596—24603

Dynamic monitoring of immune function indexes in COVID-19 patients

Yaohui Song1, *, , Huixiu Zhong1, *, , Lin Li2, , Minggang Yin1, , Yi Yin1, , Xiaolong Guo1, , Bo Zhang1, , Weiping Liu1, ,

  • 1 Department of Clinical Laboratory, Zigong First People’s Hospital, Zigong 643000, Sichuan, China
  • 2 Department of Laboratory Medicine, Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital, Chengdu 610072, Sichuan, China
* Equal contribution

Received: May 28, 2020       Accepted: October 20, 2020       Published: December 23, 2020
How to Cite

Copyright: © 2020 Song et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


We conducted a retrospective analysis of the clinical characteristics and dynamic variations of immune indexes in nine COVID-19 patients in Zigong, China. We used flow cytometry and enzyme-linked immunosorbent assays to measure the absolute levels of CD4 and CD8 lymphocytes and SARS-CoV-2 antibodies, respectively. We found that CRP, LDH, HBDH, CD4/CD8 and IgE levels were increased in 6/9 patients, while PA and the absolute numbers of CD4 and CD8 lymphocytes decreased in 7/9 patients. From disease onset through 63 days of follow-up, SARS-CoV-2 IgG levels were consistently higher than those of SARS-CoV-2 IgM, reaching peaks on days 28 and 13, respectively. IgM levels decreased to normal 35 days after disease onset, while IgG levels remained elevated through day 63. IgE levels varied similarly to SARS-CoV-2 IgM. Our results suggest that SARS-CoV-2 may elicit allergic immune responses in patients and that the levels of CRP, PA, LDH, and HBDH, as well as the absolute numbers of CD4 and CD8 lymphocytes could be used as early diagnostic markers of SARS-CoV-2 infection. Lastly, the dynamic variation of SARS-CoV-2 antibodies could guide the timing of blood collection for plasma exchange.


SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; WBC: white blood cell counts; CRP: C-reactive protein; ALT: alanine aminotransferase; AST: aspartate aminotransferase; LDH: lactate dehydrogenase; HBDH: hydroxybutyrate dehydrogenase; PA: prealbumin; CT: computed tomography; AIT: allergen-specific immunotherapy; ELISA: enzyme-linked immunosorbent assays.