in this work, the mechanism involved between the Ro/SSA complex, also composed of the Tripartite motif 21 alpha proteins (TRIM21alpha;) and trove domain 2 (TROVE2), has been studied with respect to autoantibodies of patients with systemic lupus eryematous, compared to autoantibodies of healthy people. The study comprises three chapters: I- In vitro and in silico analysis of molecular recognition between lupus autoantibodies and TRIM21alpha receptor; FC; II- In vitro evidence of bipolar TROVE2 immune complexes with bridges in systemic lupus pathogenesis and III- Market-free piezoelectric biosensor for the prognosis and diagnosis of systemic lupus erythematous. Samples of hinterland patients and healthy persons were provided by the La Fe hospital in accordance with the protocols laid down. After an immunoglobulins extraction and purification step, in vitro protein interaction was studied using a quartz microglass balance with attribution of dissipation factor and dual polarisation interferometria. Characterisation techniques such as infrared reflection-absorption spectroscopy by polarisation modulation, rayos-x photoelectronics spectroscopy and angle analysis were used to characterise surfaces. Pre-stationary state analysis has revealed a bipolar bridge mechanism for the two proteins, TRIM21alpha; and TROVE2. Following its identification, the immunodominant linear epittopus was mapped for TRIM21alpha, using a series of synthetic polypeptides superimposed of 21 amino acids. Epitopes recognised by autoantibodies for this protein cover the linear sequence from amino acid 151 to 183 for epitopes of hinged patients and healthy subjects, respectively. Autoantibodies of playpic patients recognised protein epittopes, allowing discrimination against healthy patients. The sequencing of the immunodominant linear epittopus, encoded as HLA DRB1 * 1304 for patients with EHL and HLA DRB1 * 0806 for the controls was corroborated by the results of the binding peptide joint of the Greater Complex of histocompatibility class II. The subdominant epitope corresponds to the PRY-SPRY domain, recently known receptor Fc of mammalian. Finally, the structure of the TRIM21alpha protein; it was determined using a new type approval model not previously submitted. Of the TROVE2 protein, the immunodominant linear epitope recognised by autoantibodies corresponds to the sequence that might correspond to amino acid 160 up to 210 for healthy subjects. However, the majority epitopo in hinged sera was not determined. It is suggested that the difference between epitopes corresponds mostly to a necrosis-induced in lupic patients, and to an apoptotic route in healthy patients. TROVE2 showed the ability to join FCS depending on the alkali cations present in the solution. The results suggest that the TROVE2-TRIM21alpha union; it is dependent on interaction with calcium linked through the MIDAS motif in the vWFA domain. Finally, a practical consequence of the whole study was the development of a marker free biosensor for systemic lupus erythematous, allowing premature detection of antiTRIM21alpha autoantibodies; and TROVE2, several years before the onset of clinical symptoms of the disease.