The homogenate precipitation and bound antibody were removed, and the residual antibody in the supernatant was measured in an ELISA assay with -Gal-BSA (Dextra Laboratories, RG, UK) as a solid phase antigene. 14 and 28, the effects of xenogeneic bone were examined on humoral immunity and cellular immunity, including the levels of IgG, IgM, C3, inflammatory factors (TNF-, IL-6), alkaline phosphatase (ALP) and the lymphocyte phenotype. The data showed that xenogeneic bone implantation experienced no potential to induce immune responses not only in humoral immunity but also in cellular immunity. To expose the risk of immunogenicity, the residual DNA and the clearance of -gal epitope were analyzed in 2 different bones (bone 1 is definitely deproteinized bone, bone 2 is definitely acellular and defatted bone). It was suggested that PF 477736 DNA of xenogeneic bone can be limited to? ?50?ng per mg dry excess weight for the restoration or regeneration with the acceptable immune risk. And -gal clearance of xenogeneic bone could be an effective risk element for improving xenograft quality management. Conclusions Through the detection of xenogeneic bone immunotoxicity, our findings indicated the supervisions of risk factors could contribute to reduce the immune risk. And the risk factors under the suitable limitation could decrease or replace animal experiment. However, it still needs to be studied within the limitation of -gal epitope to forecast rejection of xenogeneic bone more PF 477736 accurately. strong class=”kwd-title” Keywords: Xenogeneic bone, Immunotoxicity, Immune security, Risk management Background Bone grafting, like a common restorative method for bone defects, can be classified into autogenic, allogeneic, xenogeneic grafting and synthetic bone based on the sources of the implant materials. Although autogenic bone is the 1st choice used like a bone grafting material [1, 2], its software is limited due to the donor bone shortage, donor area dysfunction. Allograft software was limited by the transfer of diseases. Xenogeneic bone, which has a variety of sources and the ability of osteoinduction and osteoconduction activities, could satisfy the requirements of ideal bone graft substitutes. However, the immune risks of xenogeneic bone, which impact the security and effectiveness of the material, limit its software [3, 4]. Consequently, it is necessary to determine the security of xenogeneic bone on the immune system. The security evaluation offers two parts, immunotoxicity assessment and risk management within the immunogenicity. Safety evaluation, which means to forecast the adverse reactions of recipients immune system, is important to improve engraftment rates. The potential immunotoxicity of xenogeneic bone might include swelling, immunosuppression, immunostimulation and hypersensitivity. Although there is an approved standard for the immunotoxicity screening (ISO/TS 10993-20: 2006), methods for the detection may be assorted due to xenografts properties, such as their derivation, processing and application [5, 6]. These properties can be seemed as hazards related to the immunotoxicity of xenografts. Therefore, it is vital for the recognition and management of risks so as to minimize the risk of immunotoxicity. Immune responses, between the antigen on xenogeneic bone and the antibody in human being, may lead to a precocious re-absorption, fibrosis of the implant, implant rejection, and eventually failure of the treatment [1, 7]. Antigens, including MHC and -gal epitope, may exist in the xenogeneic scaffolds that have not been properly decellularized and may become carried by osteocytes, osteoblasts, osteoclasts and bone marrow cells [4, 8]. Studies have shown that deproteinized bone not only shed their immune reactivity but also retain their osteoinduction and osteoconduction activities [9]. And other types of xenogeneic bone are available: decalcified bone, freeze-dried bone and defatted bone [2]. Prior to the immunotoxicity assessment, the immune risk supervision of xenogeneic bone can contribute to reduce immune responses, promote the commercial bone development and software. However, there is still lack of the established criteria for the risk management of xenogeneic bone. This study focuses on immune toxicity of xenogeneic bone and tries to assess its security by the means of simulating medical use. Xenogeneic bone used PF 477736 in this study is definitely freeze-dried bovine cancellous bone scaffolds (bone 1 is definitely deproteinized bone, bone 2 is definitely acellular and defatted bone). The effects on humoral immunity and cellular immunity were analyzed to illustrate its immune toxicity TGFB4 using the proliferation of lymphocyte test and muscle implant experiments; In addition, the residual DNA and the clearance of -galactosidase (-Gal) epitope were determined and could be used as the risk factors to supervise the immune risk for xenogeneic bone application. Results Components of xenogeneic bone have no effect on human being peripheral.