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Published on: June 5, 2021
Characteristics and Prognosis of Antibody Non-responders With Coronavirus Disease 2019
Junyu Ding1,2, Changxin Liu1,2, Zhao Wang1,2
1Medical School of Chinese PLA, Beijing, China.
Insights
Some COVID-19 patients lacked antibodies but showed intense inflammation from innate immunity. Non-specific immune responses aided virus clearance, with shorter hospital stays for antibody-negative individuals.
Area of Science:
- Immunology
- Infectious Diseases
- Virology
Background:
- Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is a global pandemic.
- Limited data exists on antibody non-responders to COVID-19.
Purpose of the Study:
- To characterize COVID-19 patients who did not develop antibodies.
- To compare clinical characteristics and outcomes of antibody-negative versus antibody-positive COVID-19 patients.
Main Methods:
- Retrospective, single-center study of 1,921 COVID-19 patients.
- Patients divided into antibody-negative (n=94) and antibody-positive (n=1,827) groups.
- 1:1 propensity score matching used for group comparison.
Main Results:
- Antibody-negative patients had higher inflammatory markers (WBC, CRP, IL-6) and more men and older adults.
- Antibody-negative patients showed shorter duration for nucleic acid-negative conversion and hospitalization.
- Cough was the most common symptom in antibody-negative individuals.
Conclusions:
- Innate immunity and non-specific immune responses are crucial for virus clearance in antibody-negative COVID-19 patients.
- Intense inflammation in antibody-negative patients did not correlate with adverse outcomes.
- Further research is needed on reinfection risk and vaccination for antibody-negative individuals.
Background:
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been spreading globally. Information regarding the characteristics and prognosis of antibody non-responders to COVID-19 is limited.
Methods:
In this retrospective, single-center study, we included all patients with confirmed COVID-19 using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) admitted to the Fire God Mountain hospital from February 3, 2020, to April 14, 2020. A total of 1,921 patients were divided into the antibody-negative (n = 94) and antibody-positive (n = 1,827) groups, and 1:1 propensity score matching was used to match the two groups.
Results:
In the antibody-negative group, 40 patients (42.6%) were men, and 49 (52.1%) were older than 65 years. Cough was the most common symptom in the antibody negative group. White blood cell counts, neutrophils, C-reactive protein, procalcitonin, interleukin-6, lactate dehydrogenase, creatine kinase, creatine kinase isoenzyme, urea nitrogen, and creatinine were significantly higher in the antibody-negative patients than in the antibody-positive group (P < 0.005). The number of days of nucleic acid-negative conversion in the antibody-negative group was shorter than that in the antibody-positive group (P < 0.001). The hospitalization time of the antibody-negative patients was shorter than that of the antibody-positive patients (P < 0.001).
Conclusion:
Some COVID-19 patients without specific antibodies had mild symptoms; however, the inflammatory reaction caused by innate clinical immunity was more intense than those associated with antibodies. Non-specific immune responses played an essential role in virus clearance. There was no direct correlation between excessive inflammatory response and adverse outcomes in patients. The risk of reinfection and vaccination strategies for antibody-negative patients need to be further explored.
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