Chicken anti-protein A for the detection and capturing of protein A from Staphylococcus aureus in the presence or absence of mammalian IgG.

A sandwich-ELISA for the detection of protein A from Staphylococcus aureus (SpA) is described, using chicken anti-protein A as a capture antibody and its alkaline phosphatase conjugate for the detection of bound protein A. Traditionally, protein A is detected by its binding to the Fc part of a detector antibody. This binding will be influenced by the presence of other IgG in the protein A solution. However, SpA does not react with the Fc part of chicken IgG, and it is thus possible to detect protein A in IgG containing solutions, such as eluates from protein A-columns. The method can be used to detect 1 x 10(-7) g protein A/l in the presence of serum. The method is more sensitive if no serum or IgG is present in the solution.