The in-vitro study of [10] used time-lapse photography to record trajectories of healthy and COPD-affected neutrophils migrating up gradients of interleukin-8 (IL-8), demonstrating that healthy neutrophils chemotax more efficiently, while impaired neutrophils can have weaker sensitivity to the local chemoattractant gradient, which we associate with an impaired ability to resolve tissue damage. This evidence concerns the gene CXCL8 and chronic obstructive pulmonary disease.