[Chemotactic activity in the fluid of bullous pemphigoid blisters]

By a modified Boyden technique, chemotactic activity was present in bullous pemphigoid blister fluids but was also present in the corresponding sera. Heat inactivation (56 degrees C for 30 minutes) only partially reduced the blister fluid chemotactic activity, but almost completely inhibited the activity present in pemphigoid sera. Control blister fluids exhibited some chemotactic activity, but in contrast to pemphigoid blister fluids, this activity was almost entirely abolished by heat inactivation. The chemotactic activity remaining in heat inactivated pemphigoid blister fluid was inhibited by N-CBZ-alpha-glutamyl-L-tyrosine and by antiserum to C5 but not with antiserum to C3. Our studies suggest that complement-dependent chemotactic activity is present in bullous pemphigoid blister fluids, findings which further implicate complement activation in the pathogenesis of this disease.