Mirror-image sections of the inferior turbinate mucosae of both sides were obtained from 26 patients who underwent TCA treatment on one side because of the nasal anatomy status and who eventually underwent bilateral inferior turbinectomy because of failure of the TCA treatment. Th2 cell counts, defined as counts of cells positive for anti-CD4 antibody and anti-CKR4 antibody (double-positive cells) were obtained for comparison. The differences between the TCA-treated and non-TCA-treated mucosae were analyzed by Mann–Whitney's U test.
Th2 cell infiltration was characteristically found just beneath the epithelium and in the periglandular areas. The mean count ± standard deviation of Th2 cells was 4.96 ± 2.72 cells/mm2 in the TCA-treated mucosae and 12.03 ± 7.19 cells/mm2 in the non-treated mucosae, the difference being significant (p < 0.01).
TCA treatment induces inhibition of Th2 cell infiltration. This corroborates the suggestion that TCA treatment can inhibit local type I allergic reactions.