Neutrophil adhesive dysfunction in thermal injury: the role of fibronectin

We examined neutrophil substrate adherence in 19 subjects with burns involving 1%-83% of their body surface area. Within 24 h of injury, neutrophils from burn patients demonstrated a 50% reduction in adhesion to both gelatin and plastic substrates when stimulated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP), phorbol myristate acetate, and calcium ionophore A23187. Neutrophil substrate adherence examined as long as two weeks after burn injury remained abnormal. Neutrophils, from burn patients, stimulated with FMLP, phorbol myristate acetate, and calcium ionophore A23187 demonstrated a 51%, 37%, and 45% decrease, respectively, in release of immunoreactive fibronectin compared with control neutrophils. In neutrophils from burn patients there was a 31% reduction in total neutrophil-associated fibronectin compared with controls. The decrement in release and total cellular content of fibronectin in neutrophils from burn patients did not change when reexamined on day 7 after injury. The magnitude and time course of alterations in the cellular content and release of fibronectin correlate with adhesive dysfunction after burn injury.