Immunolocalization and distribution of the NH₂- and COOH-terminal DSP fragments in mouse teeth.

<p><b>A</b>-<b>C</b>. Anti-NH₂- and anti-COOH-terminal DSP domain antibodies in mouse first molars at 1.5M (b–c), 7.5M (e–f), 13.5M (h-i). HE staining of the first mandibular molars was shown at a, d and g. <b>b</b>, <b>e</b> and <b>h</b>. Intense immune distribution of the anti-NH_2-terminal DSP was apparently detected in predentin, odontoblasts and dental pulp. Also, the NH₂-terminal DSP domain was expressed in osteoblasts, PDL cells, but barely seen in cement at 1.5M (b), 7.5M (e) and 13.5 M (h). <b>b’-b’’</b>, <b>e’-e’’</b>, and <b>h’-h</b>’’ show higher magnification of A and B boxes in b, e and h. <b>c</b>, <b>f</b> and <b>i</b>. Anti-COOH DSP antibody showed strong reactions in dentinal tubules, but weakly in predentin compared to that of the anti-NH₂-terminal DSP antibody. Expression of the COOH-terminal DSP domain was substantially seen in osteoblasts, PDL cells, and cement at 1.5M (c), 7.5M (f), and 13.5M (i). <b>c’-c’’ </b><b>, f’-f’’ </b><b>and </b><b>i’-i’’</b>. Higher magnification of A and B boxes in c, f and i. <b>a</b>, <b>d</b> and <b>g</b>. Control tissue sections were incubated with normal IgG instead of first antibodies, showing a negative reaction. <b>a’-a’’</b>, <b>d’-d’’</b> and <b>g’-g’’</b> show higher magnification of A and B boxes in a, d and g. <b>D.</b> Western blot analysis of DSP expression patterns in mouse MD10-F2 cells using the NH₂- and COOH-terminal DSP antibodies. Multiple NH₂- and COOH-terminal DSP fragments were detected in MD10-F2 cells. β-actin was used as an internal control. B, bone; C, cement; D, dentin; Dp, dental pulp; pD, predentin; Pdl, periodontal ligament cells.