Combined stimulation of nasal polyp fibroblasts with poly IC, interleukin 4, and tumor necrosis factor alpha potently induces production of thymus- and activation-regulated chemokine.

OBJECTIVE

To examine the effects of cytokines and poly IC on the expression of thymus- and activation-regulated chemokine (TARC), a potent chemoattractant for helper T-cell type 2 (T(H)2) cells, in nasal polyp fibroblasts.

DESIGN

Quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis.

SETTING

Academic research.

PARTICIPANTS

Primary fibroblast lines were established from human nasal polyp biopsy tissue specimens (n = 5) removed at polypectomy.

MAIN OUTCOME MEASURES

The expression of TARC messenger RNA (mRNA) was evaluated by real-time RT-PCR. The amount of TARC in the supernatants was measured by enzyme-linked immunosorbent assay.

RESULTS

Combined stimulation with interleukin 4 (IL-4) and tumor necrosis factor alpha (TNF-alpha) or with poly IC and IL-4 induced TARC production. Combined exposure of cells to poly IC, IL-4, and TNF-alpha resulted in substantial amounts of TARC release into the culture medium. Quantitative RT-PCR analysis revealed that simultaneous stimulation with those 3 compounds induced a tremendous increase in the amount of TARC mRNA in the nasal polyp fibroblasts.

CONCLUSION

Nasal polyp fibroblasts contribute to T(H)2 cell infiltration and RNA virus-induced exacerbation of T(H)2-type airway inflammatory conditions such as allergic chronic sinusitis.