Is anyone using a complement-coated control cell to check the rectivity of your polyspecific AHG? We currently use our Coombs control cell (IgG-coated) for a positive control and a screening cell as a negative control, but wonder if we should be checking the C3 reactivity as well. We do not use a monospecific C3 AHG beacuse there is only one commercially available control cell and our volume does not justify a standing order or the tedious process of preparing control cells.

You don't need to qc your polyAHG with a Complement check cell. If your IgG check cell works, that suffices. You only need a CCC to qc your anti-Complement monospecific reagent.