Polarization of macrophages in OTCs.

<p>Immunofluorescent staining of cryosections from OTCs against M1 and M2 markers after one and three weeks. M2 polarization of macrophages was detected by staining for the M2 markers CD-206 (A, red). High CD-206 signals were detected in OTCs containing fibroblasts and macrophages or upon treatment with IL-4. CD-206 was detected on macrophages in all 3 week setups (B). Quantification demonstrated that not only signal intensity but also the number of M2 macrophages increased upon stimulation with IL-4 and over time (C). Stimulation of OTCs with IFN-gamma and LPS results in increased numbers of macrophages positive for iNOS, an M1 marker (D), while the number of CD-206+ M2 macrophages decreased (D). Further, the signal intensity of iNOS expression of macrophages in IFN-gamma + LPS stimulated OTCs clearly increased (E), while CD-206 was not detected at all (E). Bar 10 µm.