MMP19 Is Essential for T Cell Development and T Cell-Mediated Cutaneous Immune Responses (original) (raw)
Figure 2
MMP19−/− mice show impaired ear swelling and inflammatory reaction in CHS.
(A) Five days after abdominal sensitization with the hapten (FITC), mouse ears were challenged with FITC and ear thickness was measured after 24, 48, and 72 h. Mean values are given in mm as difference to time point 0 h. (B) Hematoxylin-eosin staining of ear sections 24 h after challenge shows reduced influx of neutrophils and eosinophils in MMP19−/− mice. (C) Staining with anti-Ki-67 antibody revealed that proliferation of keratinocytes in MMP19-deficient mice was strongly reduced in basal and suprabasal layers. Ki-67-positive cells were counted and calculated as percentage of basal and total keratinocytes. Six images (magnification 400x) per mice were analyzed. (D) Decreased processing of IGFBP-3 in MMP19-deficient mice. Primary keratinocytes from MMP19+/− and MMP19−/− mice were grown for 72 h and conditioned media were analyzed for IGFBP-3 proteolysis by western blotting. The arrowhead indicates the position of intact IGFBP-3, whereas the arrow points to 30 kD IGFBP-3 proteolytic fragment. (E) Anti-CD8 staining (red) of ear sections. MMP19−/− mice show low numbers of CD8+ T cells in CHS (upper panel) as well as in a T cell-independent model of inflammation, i.e. irritant dermatitis, induced by croton oil (middle panel). Ears of unsensitized mice (lower panel) exhibit low numbers of CD8+ cells; no difference was observed between MMP19+/+ and MMP19−/− mice. CHS and irritant dermatitis were carried out in four independent experiments each with 4 wild-type and 4 MMP19−/− mice. (F) 24 h after FITC challenge ear lysates were analyzed for cytokine expression that was generally reduced in MMP19-deficient mice compared to wild-type animals. (G) Reduced levels of lymphotactin and I-TAC from three independent experiments are shown. Bars in F and G represent values of MMP19−/− mice given as fold decrease to wild-type mice. Significant values with *p<0.05 and **p<0.01; student's t-test. Scale bars: B, 50 µm; C, 20 µm; D, 50 µm.