Combinatorial hydrogel library enables identification of materials that mitigate the foreign body response in primates

The foreign body response is an immune-mediated reaction that can lead to the failure of implanted medical devices and discomfort for the recipient. There is a critical need for biomaterials that overcome this key challenge in the development of medical devices. Here we use a combinatorial approach for covalent chemical modification to generate a large library of variants of one of the most widely used hydrogel biomaterials, alginate. We evaluated the materials in vivo and identified three triazole-containing analogs that substantially reduce foreign body reactions in both rodents and, for at least 6 months, in non-human primates. The distribution of the triazole modification creates a unique hydrogel surface that inhibits recognition by macrophages and fibrous deposition. In addition to the utility of the compounds reported here, our approach may enable the discovery of other materials that mitigate the foreign body response.Leona M. and Harry B. Helmsley Charitable Trust (3-SRA-2014-285-M-R)United States. National Institutes of Health (EB000244)United States. National Institutes of Health (EB000351)United States. National Institutes of Health (DE013023)United States. National Institutes of Health (CA151884)United States. National Institutes of Health (P41EB015871-27)National Cancer Institute (U.S.) (P30-CA14051

Pleomorphic spindle cell sarcoma (PSCS) formerly known as malignant fibrous histiocytoma (MFH): a complex malignant soft-tissue tumor

A presentation defining the nature, characteristics, causation, treatment and outcome of patients with lesions formerly known as malignant fibrous histiocytoma and now as pleomorphic spindle cell sarcoma is clearly a very difficult subject. Many authors do not believe that the tumor exists and instead describe them as forms of fibrosarcomas, fibromyxoid lesions, dedifferentiated chondrosarcomas or even leiomyosarcomas. The reasons for this confusion are presumably related to the fact that the malignant pleomorphic spindle cell sarcoma does not seem to be a distinct type of lesion with specific histologic and genetic characteristics. Instead, the tumor has at least four separate histologic variations and no specific gene signature and in fact does not seem to be either familial or ethnic in presentation. In view of the fact that the tumor was traditionally the most frequently encountered malignant soft-tissue neoplasm, the world of orthopedic oncology is clearly distressed by the problems that these patients have and is joined by the radiation oncologists and chemotherapists in seeking new solutions