Microbubbles conjugated with anti-matrix metalloproteinase 2 mouse monoclonal antibody sc-13595

MMP2-MBs

Leung K.

Publication Details

Image

Table

In vitro Rodents

Background

[PubMed]

Ultrasound is the most widely used imaging modality (1), and its role in noninvasive molecular imaging is expanding with ligand-carrying microbubbles (MBs) (2). MBs are composed of spherical cavities filled with a gas encapsulated in a shell. The shells are made of phospholipids, surfactant, denatured human serum albumin, or synthetic polymer. Ligands and antibodies can be incorporated into the shell surface of MBs. MBs are usually 1–8 μm in diameter, and they provide a strongly reflective interface and resonate to ultrasound waves. MBs are used as ultrasound contrast agents in imaging of inflammation, angiogenesis, intravascular thrombus, and tumors (3-5). They also have the potential to be used for drug and gene delivery (6).

Extracellular matrix (ECM) adhesion molecules consist of a complex network of fibronectins, collagens, chondroitins, laminins, glycoproteins, heparin sulfate, tenascins, and proteoglycans that surround connective tissue cells, and they are mainly secreted by fibroblasts, chondroblasts, and osteoblasts (7). Cell substrate adhesion molecules are considered essential regulators of cell migration, differentiation, and tissue integrity and remodeling. These molecules play a role in inflammation and atherogenesis, but they also participate in the process of invasion and metastasis of malignant cells in the host tissue (8). Invasive tumor cells adhere to the ECM, which provides a matrix environment for permeation of tumor cells through the basal lamina and underlying interstitial stroma of the connective tissue. Overexpression of matrix metalloproteinases (MMPs) and other proteases by tumor cells allows intravasation of tumor cells into the circulatory system after degrading the basement membrane and ECM (9).

Several families of MMPs are involved in atherogenesis, myocardial infarction, angiogenesis, and tumor invasion and metastases (10-12). MMP expression in normal cells, such as trophoblasts, osteoclasts, neutrophils, and macrophages, is highly regulated. Elevated levels of MMPs have been found in tumors associated with a poor prognosis for cancer patients (13). MMP2 is one of the major enzymes involved in the remodeling of the left ventricle after ischemia and reperfusion (I/R) in the heart (14). Su et al. (15) conjugated anti-MMP2 mouse monoclonal antibody sc-13595 to microbubbles containing polyethylene glycol (PEG) (MMP2-MBs) for contrast-enhanced ultrasound imaging of MMP2 expression in a post-I/R remodeling rat model.

Synthesis

[PubMed]

Su et al. (15) reported the preparation of MMP2-MBs. Hexafluoride gas was dispersed by sonication of an aqueous solution of PEG, sorbitan sterate, and Tween-80 to form a PEG contrast MB (MBc). MMP2 monoclonal antibody sc-13595 (~1.4 nmol) was incubated with 1 × 107 MBc for 10 min at 4°C. Unbounded antibody was removed from MMP2-MBs by centrifugal washings. MMP2-MBs had a mean diameter of 3.36 ± 1.61 µm. Attachment of antibody to the MB shell was confirmed with flow cytometry and microscopy. The number of antibody molecules per MB was not reported.

In Vitro Studies: Testing in Cells and Tissues

[PubMed]

Su et al. (15) performed in vitro binding of MBc and MMP2-Mbs to myocardial tissue sections from normal rats and 1-week post-I/R rats. MMP2-Mbs bound abundantly within the risk area of I/R myocardial sections with rare binding in the control area. Little binding was observed with MBc in the risk area or control area. No binding was observed with MBc and MMP2-MBs in the myocardial sections of control rats.

Animal Studies

Rodents

[PubMed]

Su et al. (15) performed ultrasound studies of MBc and MMP2-MBs binding in normal rats (n = 3/group) and 1-week post-I/R rats (n = 3/group). Myocardial contrast echocardiography was first performed to induce microvascular permeability in the heart tissue. Ultrasound was then performed at 10 min after injection of MBc or MMP2-MBs (2 × 106/rat). The mean myocardial video intensity in the risk area were 1.02 ± 0.19 and 1.76 ± 0.25 for MBc and MMP2-MBs, respectively. The contrast enhancement of MMP2-MBs to the risk area was significantly higher than that of MBc (P < 0.01). No retention of MBc (1.01 ± 0.11) or MMP2-MBs (1.02 ± 0.14) was observed in the myocardial tissue of control rats. Histological and immunofluorescence staining confirmed the co-localization of MMP2-MBs to MMP2 in the risk area of 1-week post-I/R rats. No retention of MBc was observed in the risk area, and no retention of MMP2-MBs was observed in the control area. No blocking studies were performed.

Other Non-Primate Mammals

[PubMed]

No references are currently available.

Non-Human Primates

[PubMed]

No references are currently available.

Human Studies

[PubMed]

No references are currently available.

References

1.
Wells P.N. Physics and engineering: milestones in medicine. Med Eng Phys. 2001;23(3):147–53. [PubMed: 11410379]
2.
Liang H.D., Blomley M.J. The role of ultrasound in molecular imaging. Br J Radiol. 2003;76(Spec No 2):S140–50. [PubMed: 15572336]
3.
Klibanov A.L. Ligand-carrying gas-filled microbubbles: ultrasound contrast agents for targeted molecular imaging. Bioconjug Chem. 2005;16(1):9–17. [PubMed: 15656569]
4.
Lindner J.R. Microbubbles in medical imaging: current applications and future directions. Nat Rev Drug Discov. 2004;3(6):527–32. [PubMed: 15173842]
5.
Villanueva F.S., Wagner W.R., Vannan M.A., Narula J. Targeted ultrasound imaging using microbubbles. Cardiol Clin. 2004;22(2):283–98. [PubMed: 15158940]
6.
Dijkmans P.A., Juffermans L.J., Musters R.J., van Wamel A., ten Cate F.J., van Gilst W., Visser C.A., de Jong N., Kamp O. Microbubbles and ultrasound: from diagnosis to therapy. Eur J Echocardiogr. 2004;5(4):245–56. [PubMed: 15219539]
7.
Bosman F.T., Stamenkovic I. Functional structure and composition of the extracellular matrix. J Pathol. 2003;200(4):423–8. [PubMed: 12845610]
8.
Jiang W.G., Puntis M.C., Hallett M.B. Molecular and cellular basis of cancer invasion and metastasis: implications for treatment. Br J Surg. 1994;81(11):1576–90. [PubMed: 7827878]
9.
Albelda S.M. Role of integrins and other cell adhesion molecules in tumor progression and metastasis. Lab Invest. 1993;68(1):4–17. [PubMed: 8423675]
10.
Berchem G., Glondu M., Gleizes M., Brouillet J.P., Vignon F., Garcia M., Liaudet-Coopman E. Cathepsin-D affects multiple tumor progression steps in vivo: proliferation, angiogenesis and apoptosis. Oncogene. 2002;21(38):5951–5. [PubMed: 12185597]
11.
Brix, K., A. Dunkhorst, K. Mayer, and S. Jordans, Cysteine cathepsins: Cellular roadmap to different functions. Biochimie, 2007. [PubMed: 17825974]
12.
Liu J., Sukhova G.K., Sun J.S., Xu W.H., Libby P., Shi G.P. Lysosomal cysteine proteases in atherosclerosis. Arterioscler Thromb Vasc Biol. 2004;24(8):1359–66. [PubMed: 15178558]
13.
Deryugina E.I., Quigley J.P. Matrix metalloproteinases and tumor metastasis. Cancer Metastasis Rev. 2006;25(1):9–34. [PubMed: 16680569]
14.
Wang W., Schulze C.J., Suarez-Pinzon W.L., Dyck J.R., Sawicki G., Schulz R. Intracellular action of matrix metalloproteinase-2 accounts for acute myocardial ischemia and reperfusion injury. Circulation. 2002;106(12):1543–9. [PubMed: 12234962]
15.
Su H., Du Y., Qian Y., Zong Y., Li J., Zhuang R., He J., Wei Z., Zhang J., Zhou X. Targeted ultrasound contrast imaging of matrix metalloproteinase-2 in ischemia-reperfusion rat model: ex vivo and in vivo studies. Mol Imaging Biol. 2011;13(2):293–302. [PubMed: 20544295]