RETRACTED ARTICLE: In vitro and in vivo responses of macrophages to magnesium-doped titanium
Authors: Tao Cheng
Mengqi Cheng
Yan Hu
Hui Qin
Huiliang Cao
Xianlong Zhang
Yaochao Zhao
Xuanyong Liu
Bin Li
Journal: Scientific Reports (2017)
Discipline: Multidisciplinary
Keywords: immune response; macrophage polarization; titanium; magnesium; plasma immersion ion implantation
Affiliations: Department of Orthopedics, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai 200233, China., State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.

Abstract:  Modulating immune response to biomaterials through changing macrophage polarization has been proven to be a promising strategy to elicit beneficial outcomes in tissue repair. The objective of this study was to evaluate the response of macrophage polarization to titanium doped with magnesium (0.1~0.35%), which was prepared through the magnesium plasma immersion ion implantation (Mg PIII) technique. The M1/M2 polarization profile of macrophages was investigated using a murine cell line RAW 264.7 in vitro and a murine air pouch model in vivo. Our results demonstrated that the Mg PIII-treated titanium induced a higher percentage of M2 macrophages and higher concentrations of the anti-inflammatory cytokines interleukin (IL)-4 and IL-10. Genes encoding two growth factors, bone morphogenetic protein 2 (BMP2) and vascular endothelial growth factor (VEGF) were up-regulated, thus indicating the ability of the M2 phenotype to promote wound healing. The nuclear factor Œ∫B (NF-Œ∫B) signalling pathway was down-regulated. In vivo the Mg PIII -treated titanium elicited a similar effect on macrophage polarization and induced thinner fibrous capsule formation and a decrease in infiltrated cells. These results indicate that Mg PIII treatment has the immunomodulatory potential to elicit the pro-healing M2-polarized macrophage phenotype, thus providing new insight into the development of immunomodulatory biomaterials. 

Retracted: Yes

PubPeer comments:
 Different samples share with duplicated images in Figure 6. , 
 Dear Nephodia Secturata, u00a0 Thank you very much for pointing out the error. u00a0We are checking the original data and files with the cooperators to find out why it was happened. u00a0We will come up with a detailed response and contact the publisher to correct the error ASAP. u00a0We are very sorry for such an error. u00a0 Best regards , 
 Dear Dr. Liu, It has been more than a year. Would you have any updates to share, please? In particular, could you explain how the red signal in the panels that overlap is so different? In addition, there appears to be two overlapping sets of panels in Figure 7, marked below with blue and green boxes. That brings the total of overlapping concerns to three.  , 
 Could the authors please also provide the uncropped blots for Figure 5E, please? The provided blots in the Supplemental information appear to the same blots as show in the main paper, instead of the expected uncropped blots. Here is a comparison of the blots in Figure 5E and those in the Supplemental.  , 
  10 August 2020 Editor s Note: The Editorial team is currently investigating questions raised relating to the reliability of the data presented in the article. We will update readers once we have further information and all parties have been given an opportunity to respond in full. We wouldn t want the Editors to break into a sweat or anything. , 
 April 20, 2021, retraction found here: https: www.nature.com articles s41598-021-88664-z  The Editors have retracted this Article. After publication, concerns were raised that some panels within Figures 6 and 7 contain repeated features. In addition, it was found that some of the original data related to Figure 6 are missing. The Editors therefore no longer have confidence in the integrity of the data presented. Xuanyong Liu and Huiliang Cao agree with the retraction. Bin Li and Xianlong Zhang disagree with the retraction. Yaochao Zhao, Mengqi Cheng, Hui Qin, Tao Cheng and Yan Hu did not respond to the correspondence about the retraction. I thank the publisher journal staff and the authors for their cooperation. ,