Cultured mononuclear cells (MNC) from individuals homozygous or heterozygous for the defective gene causing the inherited disease cystic fibrosis (CF) synthesize three unusual "mediators" termed ciliary dyskinesia substances (CDS), which markedly affect tracheal mucociliary systems in vitro. MNC cultures from normal healthy controls do not accumulate any CDS, whereas MNC cultures from non-CF patients controls with pulmonary disease synthesized at least one CDS. The possible involvement of the CDS in pulmonary disease is being investigated. In this study, we sought to determine whether the CDS could be chemoattractants for polymorphonuclear neutrophils (PMN), since they have characteristics in common with known chemoattractants generated by alveolar macrophages. Our analyses of crude MNC culture supernates indicated that cultures from both CF genotypes accumulate significantly higher levels of PMN chemoattractants than do analogous cultures from normal healthy controls. CF homozygote MNC also generated more activity than MNC from patient controls with chronic pulmonary disease. Fractionation of MNC culture supernates by gel permeation chromatography and characterization of active fractions demonstrated six distinct PMN chemoattractants in cultures from CF genotypes; five were also present in patient control and four in normal healthy control cultures. The excessive chemoattractant activity in MNC cultures from CF genotypes and patient controls was due to several different substances produced by monocytes: (a) two components of 1,000-3,500 mol wt. (b) two fragments of C5, and (c) a fragment of C3. One C5 fragment had ciliary dyskinesia activity, the other did not. The C3 fragment chemoattractant also had ciliary dyskinesia activity and was not found in MNC cultures from patient controls. A third CDS, Which is CF-specific (5,000 mol wt), was neither chemotactic not chemokinetic and did not inhibit random PMN migration; however, fractions containing this CF-specific CDS completely inhibited PMN chemotaxis in response to three different chemoattractants. We conclude that all of the CDS can potentially play a role in the pathophysiology of lung disease, as judged by their effects on PMN movement in vitro.