Roledumab

Mutations in the Integral membrane protein 2B (ITM2B) gene are linked to the development of familial British and Danish dementias, two relatively early‐onset dementia disorders known also to be associated with Tau neurofibrillary tangles (NFTs). However, to date, the involvement of ITM2B in limbic‐predominant age‐related TDP‐43 encephalopathy neuropathologic changes (LATE‐NC) remains unclear. To address this question, we used brain samples from the University of Kentucky Alzheimer's Disease Research Center community‐based autopsy cohort. We investigated the patterns and co‐localizations of ITM2B immunohistochemistry in subiculum, CA1, CA2, CA3 and dentate gyrus of the hippocampus from brains with Alzheimer's disease neuropathologic changes (ADNC), LATE‐NC, and comorbid ADNC+LATE‐NC, as well as low‐pathology controls (n = 4 per disease state). There was frequent co‐localization between ITM2B protein and intracellular Tau pathology in ADNC; however, there was a far weaker rate of co‐localization between ITM2B and TDP‐43 pathology. There also was, as previously described, an association between ITM2B immunostaining and neuritic‐appearing amyloid plaques. Additionally, co‐localization of intracellular ITM2B pathology with Thioflavin‐S in NFTs suggested a potential role for ITM2B in marking neurons undergoing transition from relatively healthy (early NFT‐bearing cells) to more severely affected (later NFT‐bearing) cellular disease states. This study indicates that ITM2B has a relatively specific pattern of involvement in Tau‐related neurodegeneration and in neuritic amyloid plaques, while implying minimal, if any, role for ITM2B in the synergistic relationship between Tau and TDP‐43 pathologies.

To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts in vitro and promote the tendon-bone healing in rabbits.

hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues.

Flow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection ( P<0.05), Fibronectin significantly increased at 3 days ( P<0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days ( P<0.05). CCK-8 detection showed that there was no significant difference ( P>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups.

Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.