Properties of a high molecular weight neutrophil chemotactic factor, possibly derived from mast cells: evidence for chemokinetic rather than chemotactic activity.

Kay and his colleagues [1] have suggested that the neutrophil high molecular weight chemotactic factor ( NCF ) found in the serum of patients suffering from a variety of allergic diseases is mainly derived from mast cells and is therefore an indicator of mast cell activation. We have studied some of the properties of NCF obtained from patients with atopic extrinsic asthma and compared it with N-formyl-1-methionyl-1-leucyl-1-phenyl-alanine (FMLP), a chemotactic peptide [2]. A number of differences between FMLP and NCF were observed. In contrast to FMLP, checkerboard analysis showed that NCF caused random migration of neutrophils. In addition microscopic analysis of neutrophil locomotion in response to FMLP demonstrated the characteristic pseudopod formation. Furthermore, it was found that in contrast to FMLP, NCF did not cause the release of lysosomal enzymes from cytochalasin B-treated neutrophils. These results suggest that NCF has chemokinetic rather than chemotactic properties.