A report describes experiments on the effects of bone morphogenic proteins (BMPs) on engineered cartilage grown in vitro. In the experiments, bovine calf articular chondrocytes were seeded onto biodegradable polyglycolic acid scaffolds and cultured in, variously, a control medium or a medium supplemented with BMP-2, BMP-12, or BMP-13 in various concentrations. Under all conditions investigated, cell-polymer constructs cultivated for 4 weeks macroscopically and histologically resembled native cartilage. At a concentration of 100 ng/mL, BMP-2, BMP-12, or BMP-13 caused (1) total masses of the constructs to exceed those of the controls by 121, 80, or 62 percent, respectively; (2) weight percentages of glycosaminoglycans in the constructs to increase by 27, 18, or 15, respectively; and (3) total collagen contents of the constructs to decrease to 63, 89, or 83 percent of the control values, respectively. BMP-2, but not BMP-12 or BMP-13, promoted chondrocyte hypertrophy.

These observations were interpreted as suggesting that the three BMPs increase the growth rates and modulate the compositions of engineered cartilage. It was also concluded that in vitro engineered cartilage is a suitable system for studying effects of BMPs on chondrogenesis in a well-defined environment.

This work was done by Keith J. Gooch, Torsten Blunk, Donald L. Courter, Alisha Sieminski, Gordana Vunjak-Novakovic, and Lisa E. Freed of Massachusetts Institute of Technology for Johnson Space Center.

In accordance with Public Law 96-517, the contractor has elected to retain title to this invention. Inquiries concerning rights for its commercial use should be addressed to:

L.E. Freed, M.D., Ph.D.
M.I.T. E25-330
45 Carleton St.
Cambridge, MA 02139
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Refer to MSC-23647.