Relation between stimulus intensity and neutrophil chemotactic response

Summary The effect of chemotactic peptides which lack chemokinetic activity has been investigated. The neutrophil response is proportional to the logarithm of the stimulus intensity, or alternatively a power function with an exponent of 0.3. Equal responses are obtained for equal ratios between the peptide concentration in the lower compartment and the threshold concentration. The significance of Weber-Fechner's law in leucocyte chemotaxis is discussed.We thank Miss B. Zanolari, Mrs M. Marti, Mrs Hauck and Mr Dietz for excellent technical assistance. This work was supported by the Swiss National Foundation for Scientific Research.