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On a country level, for health systems striving for newly implementing QIS it is recommended to start where routine data is available, add qualitative methodologies once the QIS is getting more complex, report performance data back to service providers and be patient centred. On the inter-country level exchange of information between agencies commissioned with implementing national QIS is very much needed for.

Discontinuous antigenic sites on bee venom phospholipase A₂ (PLA) have been mapped using human monoclonal antibodies or human polyclonal serum antibodies (hpAbs) of the IgG4 isotype from beekeepers or of the IgE isotype from individuals allergic to PLA. Lysine residues of PLA have been specifically modified by acetylation or acylation by treatment with citraconic anhydride of their ε-amino groups to analyze their role in antigen-antibody binding. After the modifications, the binding of PLA to the human monoclonal antibodies is lost, whereas the binding to IgG4 hpAbs is significantly decreased. In contrast, the effect on the binding of PLA to IgE hpAbs appears to be more heterogeneous. The data indicate the importance of lysine residues as being part of B cell epitopes in PLA-specifíc antibodies of the IgG4 isotype, but less so for those of the IgE isotype.

Two human and twelve murine monoclonal antibodies directed against the main bee venom allergen phospholipase A2 (PLA) were evaluated for their fine specificity of binding to antigen and their ability to inhibit the enzymatic activity of the antigen. Antibodies were induced by natural exposure of beekeepers to bee venom or immunization of mice via different methods. Both human monoclonal antibodies (hmAbs) were previously shown to recognize the native three-dimensional conformation of PLA and are directed against discontinuous epitopes which include lysine residue at position 25 as a contact residue. In contrast, six of the murine monoclonal antibodies (mmAbs) bind to the denatured structure of the protein as determined by enzyme-linked immunosorbent assay. The epitopes recognized are located near the C-terminal end (n = 8), in the centre of the polypeptide (n = 1), near the N-terminal end (n = 1) or include the carbohydrate part (n = 2) of the PLA molecule. The capacity of the antibodies to modify the enzymatic activity was also determined. The hmAbs significantly inhibit the enzyme (70-79%), whereas the mmAbs produced various degrees of inhibition (39-100%). Since the X-ray structure of PLA is known, the epitopes can be visualized in the context of the three-dimensional structure of the antigen. A qualitative correlation was found between the location of epitopes and the inhibition pattern. Strong inhibition was seen with those antibodies that recognize epitopes that lie on the surface of the enzyme that is thought to contact the phospholipid bilayer. The results show that even though both hmAbs and most mmAbs inhibit the enzymatic activity of PLA, the antigen-binding properties of antibodies from different species raised after different routes of immunization differ significantly. Thus, detailed epitope mapping studies using murine antibodies prepared by artificial immunization may have limited value in predicting epitope patterns relevant to an antibody response to allergens in humans naturally exposed to antigen/allergen.