Thanks to nanontechnology, crystallography and proteomics  the fine structure of the partners (not only amino acid sequence but also 3D-configuration, carbohydrate substitution, isoelectric points)  decides on ultimate properties of immune complexes conveyed by the complementarity determining regions (CDR) on the Fab recognition site of the Ig molecule. Influence of some amino acids, like tyrosin, might prevail. Immune complexes are a normal phenomenon serving to remove antigen – however, if they last and remain detectable in peripheral blood or in tissues, they express underlying pathology. Their impact on components of innate immunity is as yet ill known.

The following link goes to .pdf of our work looking at the role 25(OH)D (vitamin D) might play in regulating immunoglobulin and complement levels:

pdf Vitamin D Complement