Background: Polyposis, asthma, aspirin-intolerance and aspirin-triad are mostly accompanied with eosinophilia of mucosal airways. Chemotactic cytokines, the CC-chemokines regulated on activation, normal T-cell expressed (RANTES), eotaxin, and eotaxin-2 activate and attract eosinophilic leukocytes to the site of inflammation. This points to the implication of CC-chemokines in eosinophilia of nasal tissue of these diseases.
Methods: Therefore, nasal polypous tissue specimens of patients suffering from chronic nasal polypous sinusitis (NP), intrinsic asthma (ATA), aspirin-intolerance (AINA), and aspirin-triad (TRIAD) were investigated. The amount of mRNA and protein of CC-chemokines was analyzed using semi-quantitative reverse transcriptase polymerase chain reaction and chemokine-specific enzyme-immuno-assays. The patterns of CC-chemokines were compared.
Results: The mRNA-expression as well as protein synthesis of CC-chemokines was quantified in all tissues investigated. The expression of RANTES-mRNA in NP, ATA, AINA, and TRIAD (averaging 148-324% D-glyceraldehyde-3-phosphate dehydrogenase) and protein synthesis (0.13-0.15 ng/mg tissue weight) did not differ significantly. But the protein synthesis of eotaxin- and eotaxin-2-mRNA was significantly (P < 0.05) higher in TRIAD (3.3 pg/mg and 3.4 ng/mg tissue weight) (4 ng/mg tissue weight), than in NP, ATA, or AINA (1.8 pg/mg and 2.1 ng/mg, 2.1 pg/mg and 1.6 ng/mg, or 1.7 pg/mg and 2.2 ng/mg tissue weight, respectively).
Conclusion: Patients suffering from TRIAD in association with tissue eosinophilia were characterized by elevated eotaxin and eotaxin-2 mRNA-expression as well as protein-synthesis. This pointed to the implication of eotaxins and RANTES in eosinophilia-associated diseases. Further studies will have to prove, whether the analysis of these chemokines might improve the diagnosis of eosinophilia associated polyposis and initiate the development of new therapeutic strategies.