Figure 2. Co-expression of BSP with MMP-2 as well as DMP1 with MMP-9 in human and mouse salivary glands. Representative staining of BSP protein (LFMb-25, panel A) and message (B) in human parotid and submandibular glands, respectively. MMP-2 message is also expressed in human submandibular gland ducts (C). A similar distribution is seen for human DMP1 protein (LFMb-31) (G) and message (H), as well as for MMP-9 message (I) in submandibular ducts. In contrast to primates, mouse BSP protein (LF-83, D) and message (E) in the parotid as well as DMP1 protein (LF-148, J) and message (K) in representative female submandibular glands show that these SIBLINGs are expressed in both the non-GCT portions of all ducts and in the seromucous acini. Mouse MMP-2 message (F) and MMP-9 message (L) are also expressed in both non-GCT ducts and seromucous acini. White arrows indicate intercalated ducts, and black arrow indicate ‘basal’ cells. Treatment with proteinase K during in situ preparation destroys the fast-red counterstaining properties of mouse nuclei. Bar: 50 µm.