The transnasal administration of the extract of a parasite Ascaris suum (Asc) to mice for 3 weeks produced marked eosinophilia in the broncho-alveolar lavage (BAL) fluid. Among several strains of mice, C57BL/6 developed the most eosinophils in the BAL. C57BL/6-nu/nu mice failed to develop the pulmonary eosinophilia.
The oral administration of cyclosporin 50 mg/kg body weight every other day significantly suppressed the accumulation of eosinophils in the lung. These data indicate that the pulmonary eosinophilia caused by Asc is dependent on T lymphocytes. The mast cell deficient (WB×C57BL/6) F1-W/Wv mice developed marked eosinophilia in the BAL, which shows that mast cells are not necessary in the formation of eosinophils in this model.
