[New physiopathological findings in paraproteinemias].

Apart from their antigen-recognising function, immunoglobulins have other physicochemical properties. The best described is cryoprecipitation of monoclonal and/or polyclonal immunoglobulins. The cryoprecipitation phenomenon is unique for each cryoglobulin, and depends on the intrinsic properties of the monoclonal immunoglobulin, the protein environment, temperature and the surrounding ionic concentrations. The complement activating properties of monoclonal immunoglobulins are also unique. We have described a series of monoclonal immunoglobulins which are able to activate the classical pathway of complement without the formation of antigen/antibody complexes. Analysis of the properties of these monoclonal immunoglobulins suggests new therapeutic strategies in oncology. Monoclonal chimeric antibodies, combining antibody specific against tumour antigens and strong complement activation, may be more damaging to tumor cells than currently used antibodies.