Review Question - QID 210507

A 61-year-old man presents to his primary care doctor with shortness of breath. He reports a 6-month history of progressive dyspnea and a dry cough. He has also lost 10 pounds despite no change in his diet or exercise routine. His past medical history is notable for psoriatic arthritis and gastroesophageal reflux disease. He currently takes methotrexate and omeprazole. He has a 45-pack-year smoking history and drinks 8-10 beers per week. He previously worked as a deckhand on a large shipping vessel. Physical examination reveals minimal wheezes with decreased aeration in the left lower lung field. Mucus membranes are moist with normal skin turgor and capillary refill. A chest radiograph and computerized tomography (CT) scan demonstrate a mass in the left lower lung field. A biopsy of the mass is performed. On examination of the biopsy, the pathologist notes an area of normal lung tissue shown in Figure A. Which of the following is one of the main functions of the labeled cells?