¹¹¹In–Labelled Leukocyte Migration to the Lungs of Ovalbumin–Sensitized Guinea–Pigs after Aerosol Challenge with Ovalbumin Monitored by Gamma Scintigraphy

Abstract

Background: To determine whether antigen challenge is associated with increased accumulation of leukocytes in the lungs, the pulmonary accumulation of ¹¹¹In–labelled neutrophils and eosinophils was monitored by gamma scintigraphy. Methods: Guinea–pigs were sensitized with ovalbumin (OA) 14–21 days before challenge with aerosolized OA (10 mg/ml) for 2 min, and protected against fatal anaphylaxis by mepyramine (30 mg/kg). Comparisons were made with OA–sensitized guinea–pigs challenged with saline. 5 or 24 h following the OA challenge, guinea–pigs were anaesthetized and the jugular vein and right carotid artery were cannulated, with the contralateral artery tied off. 2MBq ^99mTc macroaggregated albumin (MAA) was injected intravenously to create a pulmonary perfusion image as a template for the lungs. ¹¹¹In–labelled neutrophils or eosinophils were then injected via the carotid artery and gamma scintigraphic images obtained. Activity in the lung region of each animal was determined by superimposing the ^99mTcMAA image of the lungs on the whole body image. Results: A significant increase in activitiy (p<0.05) in the lung region was observed after injection of ¹¹¹In–labelled neutrophils at 5 h after the OA challenge compared with saline challenge. 24 h after OA challenge there was a significant increase in activity (p<0.05) in the lung region after injection of ¹¹¹In–labelled eosinophils, but no change in activity after injection of labelled neutrophils compared with the saline–challenged animals. Conclusion: This technique models the migration of leukocyte to the lungs seen in guinea–pigs in our previous studies, namely an eosinophilia at 24 h and a neutrophilia at 5 h after OA challenge. It will therefore be useful for investigating anti–inflammatory drugs on the airways.

Lactobacillus plantarum Inhibits the Intestinal Epithelial Migration of Neutrophils Induced by Enteropathogenic Escherichia coli

“…Wright‐stained cytocentrifuge preparations show purity of the isolated neutrophils at 97% to 98% (impurity mainly from lymphocytes). Indium (111) oxine (Mallincrodt, Dayton, OH, U.S.A.) was added to label the neutrophils (9). Briefly, 0.5 μCi radioactive indium 111 was added for every 10 6 neutrophils and allowed to incubate for 15 minutes at 37°C.…”

Enteropathogenic Escherichia coli: Stimulating Neutrophil Migration Across a Cultured Intestinal Epithelium Without Altering Transepithelial Conductance

“…Neutrophils were then placed in RPMI media containing granulocyte colony stimulating factor GmCSF at10ng/ml (R&D Systems, Minneapolis, MN). Indium(III) oxine (Mallinckrodt, Dayton, OH) was used to label the neutrophils (20). Briefly, 0.5 μCi of radioactive indium was added for every 10 6 neutrophils and allowed to incubate for 15 minutes at 37°C.…”