Fig. 3.

Distinct localization of Cd19 mRNA within the lymphoid-rich areas in the granuloma. a In situ detection of Cd19 mRNA transcripts in lungs from M. tuberculosis-infected animals. For one representative of three consecutive sections per time point, the DAPI staining, Cd19 mRNA raw signals, and pseudo-color log₂ density plots are shown. Scale: 1000 μm. b Immunohistochemical labeling of CD45R/B220. Note the similar pattern of the labeling as compared with the in situ staining for Cd19 mRNA in a consecutive section at 12 wpi in a. Scale bar: 1000 μm. c The expression of Cd68, Cd3e, Cd19, and Ccr6 mRNA in one representative granuloma from C57BL/6-infected mice at 12 wpi is shown. Cd68 and Cd19 sequences locate in distinct areas of the granuloma, whereas Cd3e mRNA locates in both Cd68 and Cd19 mRNA-rich areas. Scale bar: 1000 μm. d The density of sequences in the epithelioid or lymphoid areas as defined in Supplementary Fig. 1 were quantified in three consecutive sections at 12 wpi. The ratios of sequence densities in lymphoid/epithelioid areas were calculated per section and the mean is depicted. The ratios were color coded accordingly if their relative frequency was higher (red) to Actb mRNA or if lower than the frequencies in epithelioid cells (green). Transcripts with ratios of lymphoid/epithelioid >1 and less than the ratio of Actb mRNA are depicted in blue. Source data are provided as a Source Data file