Fig. 6: Diverging intrasplenic migration patterns and morphological changes between the pDCs producing and those not producing IFN-I during MCMV infection.
a, Strategy for generating SCRIPT mice. b, Characterization by flow cytometry of Ifnb1-expressing splenocytes from SCRIPT mice at 36 h and 48 h after MCMV infection. Within live nonautofluorescent (AF−) cells, pDCs were identified as producing IFN-I (YFP+tdT+, green boxes and contour plot) or not producing (YFP−tdT+, red); other IFN-I producing cells were identified as tdT−YFP+ (violet); their expression of Ly6D and BST2 was examined. c–f, Spleen cryosections, 20 μm, from SCRIPT mice infected or not infected by MCMV stained with antibodies against indicated markers. c, The masks used for quantification shown on the right of the photographs, with pDCs in black, the TCZ in green and the MZ in blue. d, Representative images of a pDC cluster in the MZ at 36 h and of YFP+ pDCs in the TCZ at 48 h. e, Microanatomical distribution of splenic pDCs during MCMV infection. The data shown are from six animals for NI mice, nine for 36 h, seven for 40 h, eight for 44 h and nine for 48 h, with one whole spleen section analyzed per mouse. f, Fraction of YFP+ versus YFP− pDCs in the MZ or TCZ. The data are from the same mice as in e. The height of the boxes shows the mean value. A two-sided Wilcoxon’s t-test was used for the statistical analysis: *P < 0.05, **P < 0.01. g,h, Quantitative assessment of the cellular morphology of YFP+ versus YFP− pDCs from 60-h MCMV-infected SCRIPT mice, compared with pDCs and cDC2s from uninfected mice. g, One representative confocal microscopy image of each DC type. h, Distribution of the circularity indices for individual cells across DC types. The height of the boxes shows the mean value. The data shown are from 2 independent experiments each with 42–53 cells analyzed for each DC type from one mouse, as shown below the graph. The Kruskal–Wallis test was used for the statistical analysis: *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.
