摘要：To characterize passive cutaneous anaphylaxis (PCA) in the mouse ear, reactions caused by non-heated and heated antiserum were compared to those caused by monoclonal immunoglobulin E antibody (mc-IgE) and monoclonal immunoglobulin G1 antibody (mc-IgG1). Heat treatment at 56°C did not alter the activity of antiserum or mc-IgG1 to elicit the 1.5-h PCA. The 1.5-h PCA mediated by mc-IgE and 48-h PCA's mediated by both antiserum and mc-IgE were abrogated almost completely by heating at 56°C for 2 h. The 48-h PCA was not elicited by mc-IgG1. The sensitized state persisted at least for 7 d when mice were sensitized with non-heated antiserum or mc-IgE. In contrast, the sensitized state disappeared rapidly in cases of heated antiserum and mc-IgG1. In 48-h PCA's mediated by antiserum and mc-IgE, extravasated dye in the ear was detected 5 min after challenge and the reaction was terminated in 15 min. In contrast, in the 1.5-h PCA mediated by heated antiserum, the accumulation of dye in the ear was delayed slightly when compared to the 48-h PCA. In mc-IgG1-mediated 1.5-h PCA, the delay was significant. Both 1.5-h PCA's mediated by heated antiserum and mc-IgG1, and the 48-h PCA's mediated by antiserum and mc-IgE were not observed in WBB6 F1-W/Wv mice, which lack mast cells. All these PCA's were inhibited equally by tranilast, an inhibitor of mediator release from mast cells. The 1.5-h PCA was abrogated completely when heated antiserum was absorbed with a rabbit anti-mouse IgG1 serum coupled-Sepharose 4B. On the other hand, the 48-h PCA was abrogated completely by absorption of the antiserum with goat anti-mouse IgE serum coupled-Sepharose 4B. These results indicated that the 48-h PCA in mice sensitized with antiserum is mediated by IgE antibody. In the 1.5-h PCA in mice sensitized with heated antiserum, it is considered that IgG1 antibody plays a major role to elicite PCA. However, it is also considered that the reaction is modified by other serum components.
