title: Bacterial cellulose: long-term biocompatibility studies.
abstract: The bacterial cellulose (BC) secreted by Gluconacetobacter xylinus is a network of pure cellulose nanofibres which has high crystallinity, wettability and mechanical strength. These characteristics make BC an excellent material for tissue-engineering constructs, noteworthy for artificial vascular grafts. In this work, the in vivo biocompatibility of BC membranes produced by two G. xylinus strains was analyzed through histological analysis of long-term subcutaneous implants in the mice. The BC implants caused a mild and benign inflammatory reaction that decreased along time and did not elicit a foreign body reaction. A tendency to calcify over time, which may be related to the porosity of the BC implants, was observed, especially among the less porous BC-1 implants. In addition, the potential toxicity of BC nanofibres - obtained by chemical-mechanical treatment of BC membranes - subcutaneously implanted in mice was analysed through bone marrow flow cytometry and histological analyses. At 2 and 4 months post-implantation, the nanofibres implants were found to accumulate intracellularly, in subcutaneous foamy macrophages aggregates. Moreover, no differences were observed between the controls and implanted animals in thymocyte populations and in B lymphocyte precursors and myeloid cells in the bone marrow.
authors: a IBB, Institute for Biotechnology and Bioengineering, Universidade do Minho , Campus de Gualtar , 4710-057 , Braga , Portugal.
authors: Renata A N
authors: RA
authors: Pértile
authors: Susana
authors: S
authors: Moreira
authors: Rui M
authors: RM
authors: Gil da Costa
authors: Alexandra
authors: A
authors: Correia
authors: Luisa
authors: L
authors: Guãrdao
authors: Fátima
authors: F
authors: Gartner
authors: Manuel
authors: M
authors: Vilanova
authors: Miguel
authors: M
authors: Gama
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000473:pathology / Q000502:physiology; D002113:Calcification, Physiologic; D002482:Cellulose / Q000737:chemistry; D005434:Flow Cytometry; D041822:Gluconacetobacter xylinus / Q000737:chemistry; D020007:Implants, Experimental / Q000009:adverse effects; D008297:Male; D008422:Materials Testing; D008567:Membranes, Artificial; D008807:Mice, Inbred BALB C; D008855:Microscopy, Electron, Scanning; D057139:Nanofibers / Q000737:chemistry; D016062:Porosity; D040521:Subcutaneous Tissue / Q000098:blood supply / Q000473:pathology / Q000502:physiology; D013997:Time Factors
chemical_list: D008567:Membranes, Artificial; D002482:Cellulose