Superantigens and the expression of T-cell receptor repertoire in chronic rhinosinusitis with nasal polyps

Conclusions. Staphylococcal exotoxins (SEs), acting as superantigens, activate the beta variable chains of T-cell receptors (TCRV beta) with subsequent massive proliferation and corresponding excursion of gene spectra, thereby contributing to the etiology of chronic rhinosinusitis with nasal polyps (CRSwNP). Objectives. To demonstrate the presence of SEs in sinonasal mucosa, and determine the effect of superantigens on the T cells expressing the target of superantigen, i.e. TCRV beta in patients with CRSwNP. Materials and methods. Nasal mucosa and sinonasal polyp tissue specimens were obtained from 37 patients with CRS (22 with bilateral nasal polyps, 15 without nasal polyps). Specimens were assayed by enzyme-linked immunosorbent assay (ELISA) for SEs (SEA, SEB, SEC, SED) and toxic shock syndrome toxin type-1 (TSST-1), and analyzed by flow cytometry and reverse transcriptase-polymerase chain reaction (RT-PCR), respectively, to determine the expression of TCRV beta repertoire. Results. In the CRSwNP subjects 12 of 22 samples (54.54%) demonstrated reactivity for staphylococcal exotoxins. There was no positive result in the CRS without nasal polyps or normal control group. There was a high percentage of V beta(+) T cells in the superantigen-positive group. The expressional intensity of V beta 3, 14, 15, 17, and 20 was specifically enhanced in SEB-positive subjects, as well as that of V beta 2 and 6.1-3 in specimens that were TSST-1-positive compared with those that were negative for superantigens (all p<0.05). There were no dominantly expressed V beta fragments in ELISA-negative specimens.