Effect of acute nonimmune inflammation on locomotion of exudate and blood rabbit neutrophils.

The random and directed locomotion of rabbit polymorphonuclear neutrophils (PMNs) were investigated in vitro by the agarose technique. PMNs were either recruited in serum-elicited pleural exudates or isolated from blood collected before or after pleurisy development. Directed PMN migration was assessed in the presence of N-formyl-methionyl-leucyl-phenylalanine (FMLP), isologous rabbit serum (IRS) or cell-free exudates as chemotactic stimuli. Neutrophils collected from blood before pleurisy induction or 4 h afterwards displayed similar random migration, and similar migration oriented by FMLP, IRS, or cell-free exudates. However, both random and FMLP-induced migration were greater for exudate than blood PMNs. In the presence of IRS or cell-free exudate as chemoattractants, exudate and blood PMNs migrated over similar distances. These results suggest that exudation does not deactivate elicited PMNs but alters their locomotion responses according to the stimulus applied.