1 State Key Laboratory of Respiratory Disease for Allergy at Shenzhen University, Shenzhen Key Laboratory of Allergy & Immunology, Shenzhen University School of Medicine, Shenzhen, China.
2 These authors contributed equally to this work.
3 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
4 Department of Respirology & Allergy, Third Affiliated Hospital of Shenzhen University, Shenzhen, China.
5 Yangjiang People's Hospital, Yangjiang, China.
6 Department of Infectious Disease, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, China.
7 Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
8 Department of Preventive Medicine, Shenzhen University Health Sciences Center, Shenzhen, China.
9 Divisions of Human Genetics and Pulmonary Medicine, Department of Pediatrics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Humoral immune response to SARS-CoV-2 showed an early response of IgA, instead of IgM, in COVID-19 patients. As highlighted by our study, enhanced IgA responses observed in severe COVID-19 might confer damaging effects in severe COVID-19.