The use of long-chain plant polyprenols as a means to modify the biological properties of new biodegradable polyurethane scaffolds for tissue engineering. A pilot study.

Microporous membranes for tissue engineering were produced from new biodegradable polyurethane based on hexamethylene diisocyanate, poly(epsilon-caprolactone) diol and 1,4:3,6-dianhydro-D-sorbitol. The interconnected pores had an average size in the range of 5-100 microm. The tensile strength at break, the Young's modulus and elongation at break of the membranes were 3.2+/-0.3 MPa, 25.2+/-1.5 MPa and 190+/-12%, respectively, while nonporous foils from the same polymers had a tensile strength at break of 40+/-2 MPa, a Young's modulus of 91+/-6 MPa, and an elongation at break of 370+/-10%. The membranes were incubated for 10 days in a 2.65 vol% solution of long-chain plant polyprenol in n-hexane to promote their interaction with cells and tissues. The polyprenol was isolated from leaves of Magnolia cobus and was a mixture of prenol-10 and prenol-11. The prenol-impregnated membranes and nonimpregnated membranes (control) were tested in cell culture to assess whether impregnation has a beneficial effect on cell-material interaction. The cells used in the test were chondrocytes isolated from the articular-epiphyseal cartilage of leg bones of 5-day-old inbred LEW rats. The time of culture was 2 and 5 weeks. Both, the nonimpregnated and impregnated polyurethane membranes supported attachment and growth of rat chondrocytes. The cells firmly attached to the surface of the microporous membranes, invaded the pores and maintained the round shape characteristic for chondrocyte-like-morphology. Abundant fibrillar extracellular matrix produced by the cells resembled the network formed by chondrocytes in vivo. The cells produced relatively more extracellular matrix in the membranes impregnated with polyprenol than in the control membranes. Impregnation of polyurethane scaffolds with biologically active amphiphilic polyprenols may be a route to facilitate the cell-material interaction.