Localization and expression of osteopontin in the rotator cuff tendons in patients with calcifying tendinitis.

Abstract

Calcifying tendinitis of rotator cuff tendons is a common and painful condition caused by ectopic calcification in humans. To examine the involvement of osteopontin (OPN), a potent regulator of calcium deposition on connective tissues, localization and expression of OPN protein and messenger (m)RNA were investigated in human tissue samples of calcified rotator cuff tendons. Immunohistochemistry demonstrated that OPN was localized in cells surrounding the calcified area. OPN was localized in two distinct cell types, i.e., fibroblast-like cells negative for CD68 and tartrate-resistant acid phosphatase (TRAP) and multinucleated macrophages positive for CD68 and TRAP. In situ hybridization revealed that the mRNA expression of OPN in these cells coincided with the immunohistochemistry results, and these results were supported by reverse transcriptase polymerase chain reaction analysis using human OPN-specific oligonucleotides. Cells located away from the calcified area did not express OPN. The present findings indicate the involvement of OPN in the process of calcification of rotator cuff tendons and suggest that OPN plays a role in such painful disorders through the actions of at least two cell types.

• Authors: E Takeuchi, K Sugamoto, T Nakase, T Miyamoto, M Kaneko, T Tomita, A Myoui, T Ochi, H Yoshikawa
• Journal: Virchows Archiv : an international journal of pathology (Virchows Arch) Vol. 438 Issue 6 Pg. 612-7 (Jun 2001) ISSN: 0945-6317 [Print] Germany
• PMID: 11469694 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, CD
• Antigens, Differentiation, Myelomonocytic
• CD68 antigen, human
• Isoenzymes
• RNA, Messenger
• SPP1 protein, human
• Sialoglycoproteins
• Osteopontin
• Acid Phosphatase
• Tartrate-Resistant Acid Phosphatase

Topics

• Acid Phosphatase (metabolism)
• Aged
• Antigens, CD (metabolism)
• Antigens, Differentiation, Myelomonocytic (metabolism)
• Arthrography
• Calcinosis (diagnostic imaging, metabolism, pathology)
• Female
• Fibroblasts (metabolism, pathology)
• Humans
• Immunohistochemistry
• In Situ Hybridization
• Isoenzymes (metabolism)
• Macrophages (metabolism, pathology)
• Middle Aged
• Osteopontin
• RNA, Messenger (metabolism)
• Reverse Transcriptase Polymerase Chain Reaction
• Rotator Cuff (diagnostic imaging, metabolism, pathology)
• Sialoglycoproteins (genetics, metabolism)
• Tartrate-Resistant Acid Phosphatase
• Tendinopathy (diagnostic imaging, metabolism, pathology)
• Tendons (diagnostic imaging, metabolism, pathology)