Belimumab in SLE Synovial Inflammation and Lymph Nodes

Differences in lymph node cellular composition as assessed by advanced flow cytometry

Systemic lupus erythematosus (SLE)is an immune-mediated inflammatory disease (IMIDs) of which
 the cellular and molecular alterations of the immune system driving the diseases still
 remains largely unknown. Accordingly, it remains difficult to predict the individual
 patient's response to treatment. Moreover, the patient's response to treatment remains
 heterogeneous and difficult to predict, despite the development of a variety of novel and
 powerful drugs (including the so-called biologicals). Therefore, there is a clear need for
 the identification and validation of cellular and molecular biomarkers which can provide
 useful clinical information for diagnosis, classification, prognosis and treatment, as well
 as the development of new therapeutic strategies. Biomarkers can be found and analyzed in
 different body compartments, of which the peripheral blood and the intra-articular synovial
 fluid or tissue are most easily accessible. However, previous studies in RA and other IMIDs
 showed that adaptive immune responses in other tissues such as lymph nodes also play an
 important role. Investigating other immune compartments of the body such as the lymph nodes
 could result in new insights. To study the early pathogenesis of inflammatory conditions, in
 2008 our department initiated core-needle inguinal lymph node biopsy sampling. Since then
 more than 100 lymph node biopsy procedures were performed. The procedure is well-tolerated
 and, other than a small hematoma which does not require therapy in most of the cases, no
 complications were reported.
 
 In the current study, the effects of belimumab (anti-BAFF) in SLE will be investigated by
 studying the immune alterations taking place in lymph nodes in comparison to peripheral blood
 and immune alterations taking place in the end-organ, e.g. the joint (wrist, knee or ankle)
 by taking synovial biopsies during a needle- or mini-arthroscopy. This procedure has been
 performed frequently in our department over the last 15 years. In this way immune alterations
 in the lymph nodes (secondary lymphoid organ), peripheral blood (systemic) and the joint (end
 organ for the disease) will be assessed and compared.