The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global concern. Immunoglobin A (IgA) contributes to virus neutralization at the early stage of infection. Longitudinal studies are needed to assess whether SARS-CoV-2-specific IgA production persists for a longer time in patients recovered from severe COVID-19 and its lasting symptoms that can have disabling consequences should also be alerted to susceptible hosts. Here, we tracked the anti-SARS-CoV-2 spike protein receptor-binding domain (RBD) antibody levels in a cohort of 88 COVID-19 patients. We found that 52.3% of the patients produced more anti-SARS-CoV-2 RBD IgA than IgG or IgM, and the levels of IgA remained stable during 4–41 days of infection. One of these IgA-dominant COVID-19 patients, concurrently with IgA nephropathy (IgAN), presented with elevated serum creatinine and worse proteinuria during the infection, which continued until seven months post-infection. The serum levels of anti-SARS-CoV-2 RBD and total IgA were higher in this patient than in healthy controls. Changes in the composition of the intestinal microbiota, increased IgA highly coated bacteria, and elevated concentration of the proinflammatory cytokine IL-18 were indicative of potential involvement of intestinal dysbiosis and inflammation to the systemic IgA level and, consequently, the disease progression. Collectively, our work highlighted the potential adverse effect of the mucosal immune response to SARS-CoV-2 infection, and that additional care should be taken with COVID-19 patients presenting with chronic diseases such as IgAN.
【저자키워드】 COVID-19, SARS-CoV-2, humoral immune response, IgA nephropathy, intestinal dysbiosis and inflammation, 【초록키워드】 IgG, IgM, Inflammation, coronavirus, severe COVID-19, antibody, SARS-COV-2 infection, Infection, Symptom, progression, anti-SARS-CoV-2, chronic disease, Spike protein, Cohort, microbiota, longitudinal study, outbreak, RBD, IgA, Patient, Virus neutralization, Bacteria, change, Care, early stage, COVID-19 patients, Concentration, adverse effect, serum creatinine, Post-infection, Proinflammatory cytokine, acute respiratory syndrome, Serum level, domain, hosts, healthy controls, IL-18, mucosal immune, susceptible, consequence, intestinal, RBD IgA, Seven, produced, the patient, remained, the disease, elevated, contribute, coated, presenting, persist, with COVID-19, 【제목키워드】 IgA, response, role, Potential,