Distinct early IgA profile may determine severity of COVID-19 symptoms: an immunological case series

Christine Dahlke; Jasmin Heidepriem; Robin Kobbe; Rene Santer; Till Koch; Anahita Fathi; My L. Ly; Stefan Schmiedel; Peter H. Seeberger; Marylyn M. Addo; Felix F. Loeffler

We analyzed a low number of patients, but more are becoming available daily. Our arrays contain exclusively linear peptides and cannot identify antibodies that bind conformational or discontinuous epitopes. The 15-mer peptides, with an overlap of only 13 amino acids maybe too short or the overlap is insufficient to identify all significant antibodies. We considered exclusively the initially published Wuhan strain without mutations, but can quickly incorporate these mutations into the assay, since the array production method is rapid and flexible. 15 With the limitations listed above, our study contributes to the understanding of differences in the course of disease. More patients need to be included in follow-up studies, to evaluate the importance of the early IgA response and specific epitopes in developing vaccines. Future studies will consider not only seroconvalescent samples, but also the early time points.