The XS106 cell line: profile of TLR ligand responses reveals a Langerhans cell-like phenotype (102.7)

Abstract

Abstract The XS106 dendritic cell (DC) line, isolated from the epidermis of newborn A/J mice, has been characterized with respect to membrane marker expression and responsiveness to Toll like receptor (TLR) ligand (lipopolysaccharide [LPS], peptidoglycan [PGN], CpG, flagellin, R848) activation. Resting XS106 cells were positive for MHC class II, CD80, CD86, CD40, CD11c, CD11b and CD103 but did not express detectable Langerin or EpCAM. Cells expressed constitutively high levels of type 2-associated chemokines CCL17 and CCL22 but little of the type 1-associated chemokines CXCL9 and CXCL10. Stimulation (24h) with LPS, flagellin and PGN markedly up-regulated membrane marker and CCL17 and CCL22 expression, whereas both CpG and R-848 were without significant effect. Enhanced type 1 chemokine expression was inducible by culture with recombinant interferon-γ. Using a functional assay, cells migrated towards CXCL12, but not to CCL19 (ligands promoting migration to the dermis and lymph nodes, respectively). Migration was abrogated if cells were activated with LPS or PGN, but not CpG. Thus, XS106 cells have a relatively immature DC membrane marker phenotype which is not identical to that reported for either of the main skin DC populations (Langerhans cells (LC) or dermal (d)DC). The TLR ligand response pattern shows that XS106 are similar to LC and dDC with regard to their preferential type 2 chemokine profile and their pattern of migration is LC-like.