Fc Receptor Mediated Clearance, Invivo, In Patients With Recurrent Pulmonary Infections

Previous studies established defective Fc receptor mediated clearance in patients with systemic lupus erythematosis (SLE), a disorder associated with circulating immune complexes (CIC). The finding of CIC in sera of patients with cystic fibrosis and speculation that progressive CF pulmonary disease may be due to immune complex deposition prompted the present study. Accordingly, we tested Fc mediated clearance in vivo in patients with CF (N=13), other chronic inflammatory lung diseases (N=6), SLE (N=6), hypogammaglobulinemics (N=6) and normals (N=10) with the use of 51cr labeled autologous erythrocytes sensitized with anti-Rh(D) antibody. CF patients, chronic pulmonary disease patients and hypogammaglobulinemics had accelerated Fc receptor mediated clearance rates (T 1/2 =19.6 min, 16 min and 12.8 min, respectively) compared to normals (T 1/2 = 27.5 min) and patients with SLE (T 1/2 = 38.6 min). These data suggest that PC mediated clearance in chronic inflammatory diseases other than SLE reflect enhanced reticuloendothelial cell function and not the depressed clearance function found in diseases thought to be due to immune complex deposition.