부산대학교 도서관

Surfactant protein D (SP-D) is a pulmonary collectin important in lung immunity. SP-D-deficient mice ([Sftpd.sup.-/-]) are reported to be susceptible to ovalbumin (OVA)- and fungal allergen-induced pulmonary inflammation, while treatment with exogenous SP-D has therapeutic effects in such disease models. [beta]-Glucans are a diverse group of polysaccharides previously suggested to serve as fungal ligands for SP-D. We set out to investigate if SP-D could interact with 1,3-[beta]-glucan and attenuate allergic pulmonary inflammation in the presence of 1,3-[beta]-glucan. Allergic airway disease was induced in Sftpdand [Sftpd.sup.+/+] mice by OVA sensitization and subsequent challenge with OVA, 1,3-[beta]-glucan, or OVA/ 1,3-p-glucan together. Mice in the combined treatment group were further treated with a high dose of recombinant fragment of human SP-D (rfhSP-D). We demonstrated direct interaction between SP-D and 1,3-[beta]-glucan. OVA-induced mucous cell metaplasia was increased in [Sftpd.sup.-/-] mice, supporting previously reported protective effects of endogenous SP-D in allergy. OVA-induced parenchymal CCL11 levels and eosinophilic infiltration in bronchoalveolar lavage were unaffected by l,3-(3-glucan, but were reversed with rfhSP-D treatment. l,3-[beta]-Glucan treatment did, however, induce pulmonary neutrophilic infiltration and increased TNF-[alpha] levels in bronchoalveolar lavage, independently of OVA-induced allergy. This infiltration was also reversed by treatment with rfhSP-D. 1,3-[beta]-Glucan reduced OVA-induced mucous cell metaplasia, T helper 2 cytokines, and IFN-[gamma] production. rfhSP-D treatment further reduced mucous metaplasia and T helper 2 cytokine secretion to background levels. In summary, rfhSP-D treatment resulted in attenuation of both allergic inflammation and 1,3-[beta]-glucan-mediated neutrophilic inflammation. Our data suggest that treatment with high-dose SP-D protects from mold-induced exacerbations of allergic asthma. surfactant protein D; 1,3-[beta]-glucan; allergic asthma; mouse model; ovalbumin doi: 10.1152/ajplung.00090.2015.