Conclusions: Staphylococcal exotoxins (SEs), acting as superantigens, activate the beta variable chains of T-cell receptors (TCRVbeta) 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. TCRVbeta 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 TCRVbeta 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 Vbeta+ T cells in the superantigen-positive group. The expressional intensity of Vbeta3, 14, 15, 17, and 20 was specifically enhanced in SEB-positive subjects, as well as that of Vbeta2 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 Vbeta fragments in ELISA-negative specimens.