TY - JOUR T1 - The MRL/lpr Mouse Model: An Important Animal Model for Systemic Sjögren Syndrome and Polyautoimmunity JF - The Journal of Rheumatology JO - J Rheumatol SP - 157 LP - 157 DO - 10.3899/jrheum.190820 VL - 47 IS - 1 AU - MARTIN KILLIAN AU - FRÉDÉRIC BATTEUX AU - STÉPHANE PAUL Y1 - 2020/01/01 UR - http://www.jrheum.org/content/47/1/157.abstract N2 - To the Editor:We read with great interest the editorial by Mavragani and Moutsopoulos1, questioning the historical classification of Sjögren syndrome (SS) as primary or secondary.Few authors2 have published papers in line with these criticisms, but this editorial was of particular interest to us, because Dr. Moutsopoulos and his team were the ones who coined the concept of secondary SS more than 35 years ago. The authors remind us that it was specifically coined for patients with SS in a rheumatoid arthritis (RA) background, because of the clinical, serological, and genetic differences they observed between SS and SS/RA patients1. The same kind of observations were made only in patients with primary biliary cirrhosis presenting with sicca syndrome1; however, the concept of secondary SS has been improperly expanded to include the other systemic autoimmune diseases, especially systemic lupus erythematosus (SLE). We think that this expansion occurred because SS, especially secondary SS, is … Address correspondence to M. Killian, Groupe Immunité des Muqueuses et Agents Pathogènes, Faculté de Médecine Jacques Lisfranc, Pôle Santé Innovations, 10 rue de la Marandière, 42270 Saint-Priest-en-Jarez, France. E-mail: martin.killian{at}chu-st-etienne.fr ER -