Figure 2.

Xcr1 gene expression by different subsets of immune cells isolated from mice, human, and sheep. (A) Microarray analysis of the expression of the XCR1, THBD (BDCA3), CADM1, and LILRA4 (BDCA2) human genes and of the Xcr1, CD8a, Cadm1, and Siglech mouse genes in 96 different cell types or tissues, in human (top) and mouse (bottom), respectively. The human data were retrieved from the GEO database, normal tissues and cell types from the GSE7307 dataset, PBMC-derived macrophages from GSE4883, monocyte-derived DCs from GSE7509, monocyte-derived macrophages from GSM213500, and alveolar macrophages from GSE2125, and blood and tonsil DC subsets were retrieved from the E-TABM-34 dataset (Lindstedt et al., 2005) of the EBI ArrayExpress database. The data for the other leukocyte subsets directly isolated from normal human blood were described previously (Du et al., 2006; Robbins et al., 2008) and can be downloaded from http://www-microarrays.u-strasbg.fr/files/datasetsE.php. The data for the mouse were downloaded from the BioGPS public database (http://biogps.gnf.org). Green circles, pDCs (dark, blood; light, tonsil); red circles, mouse spleen CD8α⁺ DCs and human blood BDCA3⁺ DCs; orange circles, human tonsil BDCA3⁺ DCs; blue circles, mouse spleen CD11b⁺ DCs or human BDCA1⁺ DCs (dark, blood; light, tonsil); brown circles, mouse spleen; yellow circles, mouse lymph nodes; gray, all other cell types and tissues. Results are expressed as mean and SD for at least three independent values for most human data points. (B) Xcr1 expression determined by real-time PCR on sorted mouse spleen DC subsets and sheep leukocytes. Mouse DCs were defined as lin⁻CD11c⁺Bst2⁺ for pDCs, lin⁻CD11c⁺Bst2⁻CD8α⁺ for CD8α⁺ DCs, and CD8α⁻ for CD11b⁺ DCs. Results are representative of at least two independent experiments. Sheep skin lymph CD1b⁺CD26⁺ and CD1b⁺CD26⁻ DCs were sorted by flow cytometry to >99% purity. Sheep CD4⁺ T, CD8⁺ T, NK, and B cells were purified from afferent lymph, and CD14⁺ monocytes from blood, by flow cytometry sorting to >95% purity. Results are mean ± SEM of triplicate real-time RT-PCR reactions and they are representative of two different sheep for lymphocytes and of three different sheep for DCs. (C) β-galactosidase expression in splenocytes from XCR1^+/+ and XCR1^−/− mice. β-galactosidase expression was assessed by FDG staining. The results are shown from one mouse representative of at least eight animals studied in four independent experiments.