In the study of Asthma, it is critical to consider the movement of cells associated with the immune system and inflammation. Two of the main immune cells associated with asthma are termed eosinophils and neutrophils, both usually found in the lungs of asthma sufferers. This study involved the extraction and isolation of eosinophils and neutrophils in a range of asthma sufferers, these cells were then treated with a radioactive isotope of technetium (99mTc-HMPAO) and injected into the volunteers. The passage of these cells into, through, and out of the lungs of the patients was observed through scintigraphy (an external gamma camera) over a four hour period following an application of an allergen where dictated by the study. Asthma patients can be categorised into early and late allergic responder categories depending on the type of immune response that is triggered by their allergen. Three groups of asthma patients were defined; group 1 comprised of four early responders unchallenged by an allergen, group two contained four early and late responders challenged with an allergen, and group three contained four early and late responders challenged with an allergen and with corticosteroids administered to treat the allergen response. The results showed that the passage of eosinophils and neutrophils were significantly slower than the rate observed in healthy lungs in previous studies. This slow rate included patients that did not show asthma symptoms at the time, highlighting the usefulness of this method in diagnosis of asthma. In addition, the passage of eosinophils through the lungs was much quicker in test group 3 after the administration of the corticosteroids, proving the effectiveness of the drug.

For further information

Read the EBioMedicine original research article which this summary is based on ‘Imaging Inflammation in Asthma: Real Time, Differential Tracking of Human Neutrophil and Eosinophil Migration in Allergen Challenged, Atopic Asthmatics in Vivo’ (December 2014).

Visit the profile of the research ambassador, Tim Gardner, who wrote this summary.

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