Neutrophil Function in Cystic Fibrosis Patients
We will seek to enroll and consent CF patients for this study prior to their routine clinic visits. We will recruit patients who are 7 years of age or older with documented CF based on genotype analysis. This will be a single blood draw study. We will plan to draw blood based on the weight-based guidelines indicated by Children’s Medical Center that dictate amount of blood that can be drawn in a 24 hour period. For the purposes of these studies, we anticipate that 20-25 mls of blood will be sufficient from both patients and controls to have adequate numbers of neutrophils for study. We will perform ex vivo killing assays using neutrophils purified from whole blood in CF patients and normal controls. Purification of human neutrophils and these killing assays has been performed by the PI as previously described. PMN will be incubated with different laboratory and clinical isolates of Pseudomonas aeruginosa and Bcc representing the most frequently seen species that cause disease in these patients. We have preliminary data that ibuprofen, used at human physiologic doses, is directly inhibitory of the growth of both P. aeruginosa and Bcc. We will also incubate CF and normal neutrophils in the presence of ibuprofen to see if that alters killing. In select patients with certain mutations, we will see if a newly available drug, alters the killing ability of CF or normal neutrophils.
Inclusion Criteria: Subjects who are 7 years of age or older with documented CF based on genotype analysis. CF patients who visit UT Southwestern Medical Center or Children’s Hospital during the study period of 5/1/2012 through 5/1/2015 will be eligible for enrollment. Also we will enroll subjects (18 years and older) that don’t have a history of cystic fibrosis or any immunocompromised condition as a control group in this study. Normal controls will be UTSW employees that are 18 years or age or older and are free of any known immunodeficiencies by history. The potential controls will be individuals who are known to the PI. They will be asked if they want to participate and enrolled.