Autor(s): R. Tozzoli
For more than 40 years, conventional immunologic methods for the study and quantification of serum autoantibodies have been considered the basis for the diagnosis of autoimmune diseases. In the last ten years they have reached a level of diagnostic accuracy that allowed the inclusion of autoantibody lab tests among international criteria for the diagnosis and classification of the main autoimmune, systemic and organ-specific diseases. The high level of purification reached by the autoantigenes used in the tests has made possible the combination of a high diagnostic sensibility with an adequate analytic and diagnostic specificity, particularly with regard to some new autoantibodies of considerable clinical value, such as the anti-nucleosomes, the anti-transglutaminase, the anti-TSH receptor and the anti-citrullinated peptides. Recently, the new proteomic technology with its ability for the simultaneous detection of multiple antibodies, has opened new horizons for the diagnosis of autoimmune diseases. Indeed, multiplexing analysis is of considerable interest to the clinical lab for reasons of organization, logistics, management, physiopathology, and research. Emerging diagnostic technologies are representative of systems based on planar and non-planar (in suspension) microarrays. The latter includes methods using colored microspheres or nanobarcoded particles. In particular, the systems that allow the detection of colored microspheres by employing flow cytometry and the laser-fluorimetry technology, are widely employed. This method has numerous commercial applications, is rapidly expanding and has been validated world-wide in various clinical studies. In the near future, the multiplex methods will enable the analysis of autoantibody profiles, possibly improving the understanding of the autoimmunity physiopathology, allowing for an early diagnosis (thanks to the predictive value of the autoantibodies), and facilitating the introduction of antigen-specific therapy in autoimmune diseases.