| Abstract: | An experimental complement-dependent model of an acute allergic response to inhalation of Aspergillus spores has been used to examine the roles of polymorphonuclear leukocytes (PMN) and platelets in mediating this reaction as measured by decreases in arterial oxygen tensions (PaO2). Normal rabbits selectively depleted of PMN by nitrogen mustard (HN2) showed a decrease in PaO2 later than that observed in untreated animals. The HN2-treated group also showed a marked decrease in platelets after challenge, not seen in the similarly challenged untreated group or in unchallenged HN2-treated animals. These data demonstrate the importance of PMN in complement-mediated host responses to aerosols of fungal spores. In the absence of the PMN, platelets appear capable of initiating a similar, albeit delayed, reaction, thus further emphasizing the flexibility of pulmonary defense mechanisms against inhaled particles. |
