FIG. 3.

RNA-RNA in situ hybridization (blue color) and immunohistochemistry for CD68 (red color) shows that CD68-positive cells colocalize to the different mycobacterial mRNAs. CD68-positive giant cells colocalize to icl (A), narX (B), Rv2557/8 (C), kasA (D), and iniB (E). (F) A giant cell staining red for CD68 only is shown. CD68-positive cells with the morphology of macrophages were also positive for icl (G), narX (H), Rv2557/8 (I), kasA (J), and iniB (K). Not all CD68-positive cells were positive for the various mycobacterial mRNAs, as shown with arrows; those that were positive are indicated with an “M.” (L) Immunohistochemistry performed in the absence of in situ hybridization produced CD68-positive cells which stained red only. Total magnification for each section, ×900.