MoMa from patients with systemic lupus erythematosus show altered adhesive activity

The phagocytosis of apo cells in patients with systemic lupus erythematosus (SLE) has been shown to be impaired. Recognition and engulfment of dying cells are mediated by molecules and receptors that are also involved in cell adhesion. Therefore, we analysed the adhesion capabilities of MoMa from patients with SLE. We employed a colorimetric assay to quantify the adhesion of MoMa to various substrates. In addition, we evaluated the morphological characteristics of the MPhi adhesion cultures by phase contrast microscopy. We have observed various morphologic characteristics depending on the adhesive substrate. The typical spindle shaped MoMa adhered to plastic and a bigger and rounder formed MoMa adhered to immunoglobulin (Ig) coated surfaces. Quantitatively, adhesion to plastic was significantly decreased in some SLE patients. Those patients showing a defective adhesion to plastic simultaneously showed an enhanced adhesion to Ig coated surfaces. These findings suggest that there is an alteration in the integrin and/or FcgammaR mediated stimulation of MoMa from SLE patients and this alteration may be associated with the impaired clearance of apo cells seen in this disease.