RESUMEN
Background/Objective B-cell activating factor (BAFF) plays an important role in the pathogenesis of systemic lupus erythematosus. However, the role of BAFF in lupus nephritis (LN) is not understood. Our aim was to evaluate the expression of BAFF and its three receptors in renal biopsy samples from patients with LN and investigate a relationship with pathological class. Methods We conducted a prospective descriptive study (2011-2014) on 52 kidney biopsy samples from patients with LN. Immunohistochemistry for BAFF, its receptors (transmembrane activator and calcium modulator and cyclophilin ligand interaction (TACI), protein maturation of B cells (BCMA), and BAFF-receptor (BAFF-R)), and CD20 expression was performed. Samples were scored according to the percentage of cells with positive expression. Results In class II LN, BAFF-R and TACI were not expressed, whereas BCMA and BAFF were lowly expressed in the interstitial inflammatory infiltrates. Proliferative class III/IV had elevated BAFF expression in the glomeruli, and TACI was expressed in interstitial inflammatory infiltrates and the glomeruli. Interestingly, the class IV cases with vasculopathy ( n = 4) had endothelial BAFF expression, which was not visible in thrombotic microangiopathy ( n = 4). Class V was characterized by low BAFF expression in interstitial inflammatory infiltrates and by BAFF, TACI, and BCMA expression in the glomeruli. BAFF expression was associated with inflammatory scores and CD20 positive infiltrates, mainly in class IV. Conclusions Expression patterns of BAFF and its receptors differ according to LN class. Our study provides evidence that BAFF could be used as a routine marker in LN biopsies and to determine which patients will benefit from anti-BAFF therapy.
Asunto(s)
Factor Activador de Células B/análisis , Receptor del Factor Activador de Células B/análisis , Antígeno de Maduración de Linfocitos B/análisis , Riñón/inmunología , Nefritis Lúpica/inmunología , Proteína Activadora Transmembrana y Interactiva del CAML/análisis , Antígenos CD20/análisis , Biomarcadores/análisis , Biopsia , Humanos , Inmunohistoquímica , Riñón/patología , Nefritis Lúpica/patología , Estudios Prospectivos , Índice de Severidad de la EnfermedadRESUMEN
We present two cases of patients with systemic autoimmune diseases (one with dermatomyositis and one with CREST syndrome) who presented with a worsening of calcinosis cutis after treatment of osteoporosis with teriparatide. To our knowledge, this association is not described in the literature and might be considered in the spectrum of adverse reactions to teriparatide.