CF And Effects of Drugs Mixed Ex Vivo With Sputum for Mucolytic Treatment
CF And Effects of Drugs Mixed Ex Vivo With Sputum for Mucolytic Treatment
The investigators will collect samples of sputum from healthy volunteers and patients with
 cystic fibrosis for the purpose of: a) purifying airway mucins for plate-based binding
 studies and; b) assessment of the effects of carbohydrates on the rheologic properties of the
 sputum.

 This study has two hypotheses:

 1. Lectins from Pseudomonas aeruginosa and Aspergillus fumigatus bind to airway mucins in a
 fucose-dependent manner, and this binding can be inhibited by fucosyl glycomimetic
 compounds.

 2. Fucosyl glycomimetics will compete with Pseudomonas aeruginosa lectin (PA-IIL) and
 Aspergillus fumigatus lectin (AFL) and disrupt lectin-driven mucin cross-linking in CF
 sputum.
Pseudomonas lung infection is a major cause of morbidity and mortality occurring in multiple
 clinical settings. Patients with cystic fibrosis have lung colonization with Pseudomonas from
 an early age, and overwhelming pseudomonal lung infection is the most common cause of death
 in these patients. In addition, Pseudomonas pneumonia is common in immunocompromised patients
 and in patients intubated for management of respiratory failure. Particularly worrisome is
 the increasing frequency of P. aeruginosa isolates that are resistant to all or most
 currently available antibiotics. The mechanism of virulence of P. aeruginosa includes soluble
 lectins that recognize host oligosaccharides on mucins and the cell glycocalyx. P. aeruginosa
 has two soluble lectins - LecA, also known as PA-IL and LecB, also known as PA-IIL. PA-IL
 binds galactose and PA-IIL binds fucose. Notably, PA-IIL binds the fucose containing Lewis a
 oligosaccharide with very high affinity and the role of PA-IIL in biofilm formation is shown
 by the absence of biofilm formation in Pseudomonas mutants lacking PA-IIL and by the efficacy
 of multivalent fucosyl-peptide dendrimers in preventing and disrupting Pseudomonas biofilm
 formation. D-galactose and L-fucose have been successfully used to treat P. aeruginosa
 infection in a case report, which hints at the potential for glycomimetic therapy in CF.
 These monosaccharides are weak inhibitors of PA-IIL, however, and multivalent glycomimetics
 will be needed for more effective inhibition.

 Aspergillus fumigatusinfection is responsible for the majority of human and animal
 aspergillosis disease, even though air sampling studies show that its conidia usually
 comprise only a small percentage of total airborne fungal challenge. It is both a primary and
 opportunistic pathogen, and it is particularly troublesome for patients with cystic fibrosis.
 It causes multiple lung diseases, includingchronic pulmonary aspergillosis, allergic
 bronchopulmonary aspergillosis, and invasive pulmonary aspergillosis. Aspergillomas also
 occur in patients with cavitary lung diseases. Together, these diseases cause significant
 morbidity and mortality, and available treatments are suboptimal. Most patients with chronic
 pulmonary aspergillosis require antifungal therapy for many months or years, many experience
 significant drug side effects, and some experience drug resistance. Patients with either
 allergic bronchopulmonary aspergillosis (ABPA) or severe asthma with fungal sensitization can
 improve with itraconazole treatment, but relapses are common, and itraconazole affects
 corticosteroid metabolism and has the potential to worsen steroid side effects. ABPA requires
 long-term treatment because Aspergillus airway colonization is difficult to eradicate and
 quickly recurs when treatment is stopped. Immunocompromised patients are especially
 vulnerable to invasive aspergillosis where the mortality rate is often 50%, even with
 antifungal treatment. Clearly, therefore, new treatment approaches are needed for lung
 diseases caused by A. fumigatus, and we are proposing an approach based on prevention of
 binding to airway mucins. Adherence of A. fumigatus conidia to host tissues has been the
 subject of extensive research, but little attention has been directed to Aspergillus/mucin
 interactions, a surprising deficiency given the role mucins play in airway biology.

 This study is an ex-vivo study in which we will collect samples of sputum from healthy
 volunteers and patients with cystic fibrosis for the purpose of: a) purifying airway mucins
 for plate-based binding studies and; b) ex-vivo assessment of the effects of carbohydrates on
 the rheologic properties of the sputum.
Inclusion Criteria:

 -  Healthy control subjects:

 -  Age 18-65

 -  No history of lung disease

 -  Cystic fibrosis subjects:

 -  Age 18-65

 -  No history of lung disease other than cystic fibrosis

 -  Diagnosis of CF if sweat chloride values > 60 mM on two separate pilocarpine
 iontophoresis sweat tests and/or two allelic CF-producing mutations in genetic
 analysis

 Exclusion Criteria:

 -  Use of recreational drugs within 30 days prior to enrollment

 -  Use of tobacco within 30 days prior to enrollment, or > 10 pack-year tobacco history

 -  Pregnant or lactating females