Journal of Biomedical Materials ResearchVolume 12, Issue 5 p. 767-771 Note Acid phosphatase activity as enzymatic assay of biomedical compatibility of polymers V. F. Burpee, V. F. Burpee Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorR. W. Hackenberg Jr., R. W. Hackenberg Jr. Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorD. V. Hillegass, D. V. Hillegass Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorR. J. Arconti, R. J. Arconti Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorW. V. Sharp, W. V. Sharp Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this author V. F. Burpee, V. F. Burpee Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorR. W. Hackenberg Jr., R. W. Hackenberg Jr. Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorD. V. Hillegass, D. V. Hillegass Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorR. J. Arconti, R. J. Arconti Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this authorW. V. Sharp, W. V. Sharp Vascular Research Laboratory, Akron City Hospital, Akron, Ohio 44309 Goodyear Research Division, Akron, Ohio 44305Search for more papers by this author First published: September 1978 https://doi.org/10.1002/jbm.820120514Citations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume12, Issue5September 1978Pages 767-771 RelatedInformation

Presented at the Fourteenth Annual Meeting of The American College of Angiology. San Juan, Puerto Rico, December 3-8, 1968. This research was supported in part by United States Public Health Service Grant HE-10122-03 and the Akron District Heart Association, Inc. The human body has a curious rejection process for any synthetic or foreign matter that is brought into its sphere of influence. Granulation tissue is laid down around a foreign object and it is soon encapsulated in a fibrous capsule. This is the general basis for the tissue compatibility of the many numerous synthetic materials used for repair of various areas of the body. This same process is applicable to the vascular system. Their rejection phenomenon is unique in that not only is the outer surface encapsulated, but also the surface next to the flowing blood stream is similarly involved in an encapsulating process. So far, material has not been developed that will obviate either of these processes. The encapsulation on the inner surface or blood interface goes by several names, but is best described by the term neointima. The latter consists of several layers of fibrin with entrapped blood elements. These blood cells have the power of differentiation into endothelial cells and fibroblasts, both of which make up the mature neointima. The period of development of the neointima passes through two stages: (1) layer of organized clot, and (2) a living tissue layer of endothelial-lined fibrous tissue. 1-3 The antithrombogenic influence of the vascular interface is directly dependent upon this neointimal layer. The long-term acceptance of a foreign material in any area of the vascular system is dependent on the viability of this delicate layer. The materials that are presently used in the vascular system are confined mostly to Dacron and Teflon. Besides possessing good tensile strength and an extended durability, and minimal tissue reactivity, they promote a viable

Surgical Cardiovascular Research Laboratory of Akron City Hospital and the Goodyear Tire and Rubber Company Research Department, Akron, Ohio