Evaluating the Clinical and Biological Response of an Acetone-Precipitated Cat Hair Allergen Extract (AP Cat) in a Nasal Allergen Challenge (NAC).
The goal of this study is to learn if a cat allergen extract known as Allergenic Extract Standardized Cat Hair Acetone Precipitated (AP Cat) can induce allergic rhinitis (AR) in a nasal allergen challenge model in cat-allergic people. The main questions this study aims to answer are: 1. Does AP Cat induce nasal symptoms of allergic rhinitis in cat-allergic participants when delivered intranasally? 2. Does AP Cat reduce elements in the blood and nose that are known to be associated with allergies? Both allergic and non-allergic participants will be recruited into this study. Allergic participants will: * Be challenged with AP Cat via the Nasal Allergen Challenge (NAC), which involves administration of this allergen extract directly into the nose. * Have nasal fluid and blood samples collected at various timepoints up to 24 hours after exposure to the allergen in the NAC. * Visit the study site three separate times: 1. At screening (Visit 1), to determine eligibility to participate in this study 2. At the baseline NAC visit (Visit 2) 3. At the 24-hour post-NAC follow-up visit (Visit 3) * Complete nasal symptom questionnaires. * Complete a questionnaire about their regular exposure to cats. Non-allergic participants will: * Be challenged with AP Cat via the NAC, which involves administration of this allergen extract directly into the nose. * Have nasal fluid and blood samples collected at various timepoints up to 24 hours after exposure to the allergen in the NAC. * Visit the study site three separate times: 1. At screening (Visit 1), to determine eligibility to participate in this study 2. At the baseline NAC visit (Visit 2) 3. At the 24-hour post-NAC follow-up visit (Visit 3) * Complete nasal symptom questionnaires. This study will compare the nasal symptoms and allergic markers collected from the nasal fluid and blood samples between allergic and non-allergic participants at baseline and various timepoints post-NAC exposure.
⁃ To be considered for inclusion in this study, all participants must be:
• A healthy, ambulatory male, female, or intersex volunteer between the ages of 18 to 70 years of age.
• Able to understand and willing to provide written informed consent.
• Able and willing to comply with study requirements.
⁃ To be enrolled as an allergic participant, participants must:
• Have a minimum 2-year history of AR symptoms upon exposure to cats.
• Have a positive skin prick response to AP cat allergen, defined as a wheal diameter ≥ 5 mm compared to the negative control wheal. This result must be achieved at visit 1.
• Have a TNSS of greater than or equal to 8/12 and at least a 50% drop in PNIF in response to the allergen titration challenge at visit 1.
⁃ To be enrolled as a non-allergic participant, participants must:
• Produce a negative skin test response to a panel of relevant aeroallergens tested at visit 1 or within 12 months before visit 1 at the research site.
• Produce a negative Nasal Allergen Challenge, defined by a TNSS response of less than 4/12 and a PNIF reduction of less than or equal to 20% after 10 minutes in response to the highest allergen concentration at visit 1.