Analytical validation of an alternative method to quantify specific antibodies in 3 applications.

The detection and the quantification of specific antibodies represent essential tools for the diagnosis and for the biological monitoring of immune humoral response in many clinical situations in particular in autoimmune diseases or in the context of immunotherapy using monoclonal antibodies. This article focuses on the development of a specific antibody measuring method (Patent n°PCT/IB2014/064437). The principle of this method is based on the combined use of a monoclonal antibody as standard and the protein G as immunoglobulins detecting agent. We performed a complete analytical validation of this method for the quantification of antibodies in three different applications: autoantibodies, alloantibodies and therapeutic monoclonal antibody. The results showed good performances compatible with the use of these assays as diagnostic tools. This method allows avoiding the use of products from human origin as reagent that causes ethical and infectious concerns but also storage and long term stock management problems. Moreover, this approach is particularly useful when no commercial reagent is available, especially in the case of rare diseases.