Woodsmoke Particulate + Hypertonic Saline
Woodsmoke Particulate + Hypertonic Saline
Deployment of military personnel has been associated with increased respiratory illness
 likely due, in part, to inhalation of unusual particulate matter (PM), such as from burn
 pits. Inflammation is a key initial response to inhaled particulates. The investigator has
 developed a protocol using inhaled wood smoke particles (WSP) as a way to study PM-induced
 airway inflammation. Exposure to wood smoke particles causes symptoms, even in healthy
 people, such as eye irritation, cough, shortness of breath, and increased mucous production.
 The purpose of this research study is to see if a single treatment of inhaled hypertonic
 saline (HS) can diminish this PM-induced airway inflammation by rapidly clearing the WSP
 inhaled particles from airway surfaces. The exposure will be 500 ug/m³ of WSP for 2 hours,
 with intermittent exercise on a bicycle and rest. The wood is burned in a typical wood stove
 and piped into the chamber.
Military deployment is associated with exposure to novel particulate matter (PM), such as
 from burn pits, aeroallergens, and increased cigarette consumption. War fighters exposed to
 these inhalational exposures exhibit immediate and chronic respiratory morbidity. For
 example, military service personnel surveyed in both the Republic of Korea (ROK) and Kabul,
 Afghanistan reported a general increase in respiratory morbidity, including asthma and
 chronic bronchitis, associated with their deployment. Air contaminants in the ROK were
 characterized by elevated levels of both PM 0.5-2.5 and PM 2.5-10. Similarly, exposures in
 Kabul were characterized by multiple airborne PM exposures, including those from burn pits.
 Burn pit PM includes metals, bioaerosols, organic by-products, and biomass combustion
 particles. These findings indicate that inhaled PM is a likely cause of respiratory morbidity
 in the field.

 Inflammation is a key initial response to inhaled particulates. Wood smoke particles (WSP)
 serve as a model agent to study PM-induced bronchitis. WSP inhalation generates reactive
 oxidant (and nitrosative) species which cause local injury of airway epithelial cells and
 release of damage-associated molecular patterns (DAMPs) that activate toll-like receptors
 (TLR) and interleukin 1 (IL-1)-mediated innate immune responses by resident airway
 macrophages. Contamination of PM with bioaerosols, which contain lipopolysaccharide (LPS),
 also activates innate immune responses through toll-like receptor 4 (TLR4) activation of
 resident airway macrophages. These complementary processes result in recruitment of
 neutrophils (PMN), which mediate luminal airway inflammation with release of toxic mediators
 such as neutrophil elastase and myeloperoxidase that promote acute and chronic bronchitis.

 Therefore, mitigation of PM-induced airway neutrophilic inflammation should be a key focus in
 order to reduce the respiratory morbidity of military personnel. The investigators have
 studied a number of pro-inflammatory inhaled agents, such as nebulized LPS, ozone (O3), and
 WSP, as models of acute neutrophilic bronchitis against which to test a number of therapeutic
 agents. To this effect, the investigators have reported that inhaled fluticasone inhibits
 O3-induced and LPS-induced neutrophilic inflammation, and that parenteral anakinra and oral
 gamma-tocopherol inhibit neutrophilic responses to inhaled LPS. In addition to agents with
 inherent anti-inflammatory and anti-oxidant properties, rapid clearance of inhaled particles
 from airway surfaces is a complementary approach to reduce PM-induced airway inflammation.
 This can be assessed through the measurement of mucociliary clearance (MCC).

 MCC is dependent on airway secretory cells and submucosal glands that produce a mucin-rich
 fluid layer on the airway surface and ciliated cells that hydrate and propel mucus out of the
 lung and into the upper airway. Rates of MCC are dependent on ciliary beat frequency,
 hydration, and the rheologic properties of mucus. In vitro studies have demonstrated that HS,
 through an osmotic effect on airway surfaces, improved hydration and mucus rheologic
 properties, and accelerated mucus transport rates. In addition, the data over the last 30
 years has shown that inhaled hypertonic saline (HS) plus cough is the most effective method
 for acutely clearing the bronchial airways of inhaled, deposited particles. The combined
 effect is greater than either HS or cough alone. In the studies of asthmatics, the
 investigators examined the ability of a single HS treatment with a coached cough maneuver to
 acutely clear radiolabeled Tc99m sulfur colloid particles from airways following LPS
 exposure. Following HS inhalation and cough clearance maneuvers developed to recover sputum
 samples for analysis, the investigators observed a rapid clearance of >50% of the inhaled
 radiolabelled particles. The investigators hypothesize that if other pro-inflammatory
 particles (PMs, burn pit particles) were cleared similarly via HS-induced acceleration of MCC
 shortly after exposure, there would be reductions in acute PM-induced inflammation. Thus, in
 this study, the investigators will assess the effectiveness of inhaled 5% HS, a dose well
 tolerated by asthmatics at baseline and after inhaled LPS/allergen challenges for sputum
 induction, in mitigating WSP-induced airway neutrophilic inflammation in healthy volunteers.
 Normal saline 0.9% (NS) is not going to be used as a placebo treatment in this study, as
 inhalation of NS itself impacts the rheologic properties of mucus and MCC and thus would not
 be a suitable placebo. The investigators will, therefore, compare treatment with 5% HS to no
 receiving no treatment following WSP exposure.
Inclusion Criteria:

 -  Age 18-45 years, inclusive, of both genders

 -  Negative pregnancy test for females who are not s/p hysterectomy with oophorectomy

 -  No history of episodic wheezing, chest tightness, or shortness of breath consistent
 with asthma, or physician-diagnosed asthma.

 -  forced expiratory volume at one second (FEV1) of at least 80% of predicted and
 FEV1/forced vital capacity (FVC) ratio of >0.70.

 -  Oxygen saturation of >93%

 -  Ability to provide an induced sputum sample.

 -  Subject must demonstrate a >10% increase in sputum %PMNs 6 hours following inhaled WSP
 exposure, when compared to baseline sputum (to be completed in a separate protocol
 IRB# 15-1775).

 Exclusion Criteria:

 -  Clinical contraindications:

 -  Any chronic medical condition considered by the PI as a contraindication to the
 exposure study including significant cardiovascular disease, diabetes, chronic renal
 disease, chronic thyroid disease, history of chronic infections/immunodeficiency.

 -  Viral upper respiratory tract infection within 4 weeks of challenge.

 -  Any acute infection requiring antibiotics within 4 weeks of exposure or fever of
 unknown origin within 4 weeks of challenge.

 -  Abnormal physical findings at the baseline visit, including but not limited to
 abnormalities on auscultation, temperature of 37.8° C, Systolic BP > 150mm Hg or < 85
 mm Hg; or Diastolic BP > 90 mm Hg or < 50 mm Hg, or pulse oximetry saturation reading
 less than 93%.

 -  Physician diagnosis of asthma

 -  If there is a history of allergic rhinitis, subjects must be asymptomatic of allergic
 rhinitis at the time of study enrollment.

 -  Mental illness or history of drug or alcohol abuse that, in the opinion of the
 investigator, would interfere with the participant's ability to comply with study
 requirements.

 -  Medications which may impact the results of the WSP exposure, interfere with any other
 medications potentially used in the study (to include steroids, beta antagonists,
 non-steroidal anti-inflammatory agents)

 -  Cigarette smoking > 1 pack per month

 -  Unwillingness to use reliable contraception if sexually active (IUD, birth control
 pills/patch, condoms).

 -  Use of immunosuppressive or anticoagulant medications including routine use of NSAIDS.
 Oral contraceptives are acceptable, as are antidepressants and other medications may
 be permitted if, in the opinion of the investigator, the medication will not interfere
 with the study procedures or compromise safety and if the dosage has been stable for 1
 month.

 -  Orthopedic injuries or impediments that would preclude bicycle or treadmill exercise.

 -  Inability to avoid NSAIDS, Multivitamins, Vitamin C or E or herbal supplements.

 -  Allergy/sensitivity to study drugs or their formulations

 -  Pregnant/lactating women and children (< 18 years as this is age of majority in North
 Carolina) will also be excluded since the risks associated with WSP exposure to the
 fetus or child, respectively, are unknown and cannot be justified for this
 non-therapeutic protocol. Individuals over 45 years of age will not be included due to
 the increased possibility of co-morbidities and need for prohibited medications.

 -  Inability or unwillingness of a participant to give written informed consent