No. Levels of mucosal secretory IgA do not necessarily predict or determine serum IgA levels – and vice versa. In serum, IgA is the second most abundant antibody after IgG. Secretory IgA (SIgA) is produced from two IgA molecules. However, adequate IgA is not the only factor impacting SIgA production. Stress is just one example of a negative impact on low SIgA.
If my secretory IgA levels are low, does that mean my serum IgA levels are low, too?
Adair
