Fibronectin binding and neutrophil aggregation in burn injury.
Fibronectin (Fn) plays an important role in the adhesive function of many cells including neutrophils (PMN). We examined the hypothesis that activated PMN develop binding sites for fibronectin which allows for the aggregation of contiguous PMN. Because PMN adhesive function is altered in acute burn injury, we also investigated the role of Fn in the aggregation of PMN from subjects with acute thermal injury. The chemotactic peptide, n-formylmethionyl leucyl phenylalanine, induced rapid binding of radioiodinated plasma Fn to PMN. Significant binding of Fn was detected as early as 30 sec poststimulus and maximal binding occurred at 5 min. Fn binding was only partially reversible and nonsaturable. The chemotactic peptide induced aggregation and binding of Fn to PMN with similar kinetics, concentration dependence, temperature, and cation requirements. In burn patients, PMN demonstrated a significant decrease in chemotactic peptide-induced aggregation which was associated with decreased binding of Fn. Alterations in the binding of Fn to PMN may be responsible, in part, for diminished aggregation responses of PMN in the early stages of thermal injury.
Spagnuolo
P J
PJ
Department of Medicine, Case Western Reserve University School of Medicine, MetroHealth Medical Center/Cleveland Metropolitan General Hospital, Ohio 44109.
Donofrio
B
B
Litzenberg
W E
WE
Fratianne
R B
RB
Marino
J A
JA
D002056:Burns / Q000097:blood*; D002449:Cell Aggregation / Q000502:physiology; D003571:Cytochalasin B / Q000494:pharmacology; D005353:Fibronectins / Q000378:metabolism*; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000502:physiology*
D005353:Fibronectins; D007457:Iodine Radioisotopes; D003571:Cytochalasin B; D009240:N-Formylmethionine Leucyl-Phenylalanine