Diabetes-Induced NF-κB Dysregulation in Skeletal Stem Cells Prevents Resolution of Inflammation.

Type 1 diabetes (T1D) imposes a significant health burden by negatively affecting tissue regeneration during wound healing. The adverse effect of diabetes is attributed to high levels of inflammation, but the cellular mechanisms responsible remain elusive. In this study, we show that intrinsic skeletal stem cells (SSCs), a subset of mesenchymal stem cells, are essential for resolution of inflammation to occur during osseous healing by using genetic approaches to selectively ablate SSCs. T1D caused aberrant nuclear factor-κB (NF-κB) activation in SSCs and substantially enhanced inflammation in vivo. Constitutive or tamoxifen-induced inhibition of NF-κB in SSCs rescued the impact of diabetes on inflammation, SSC expansion, and tissue formation. In contrast, NF-κB inhibition in chondrocytes failed to reverse the effect of T1D. Mechanistically, diabetes caused defective proresolving macrophage (M2) polarization by reducing TGF-ß1 expression by SSCs, which was recovered by NF-κB inhibition or exogenous TGF-ß1 treatment. These data identify an underlying mechanism for altered healing in T1D and demonstrate that diabetes induces NF-κB hyperactivation in SSCs to disrupt their ability to modulate M2 polarization and resolve inflammation.

Relationship between the HLA-G 14 bp insertion/deletion polymorphism and susceptibility to autoimmune disease: a meta-analysis.

Numerous studies have investigated the potential relationship between the human leukocyte antigen (HLA)-G 14-bp insertion/deletion (INS/DEL) polymorphisms and autoimmune disease (AID). However, published results are inconclusive. Our aim was to determine whether the 14-bp INS/DEL polymorphism in the HLA-G gene contributes to the risk of AID. A systemic literature search of the PubMed and EMBASE databases was conducted to identify eligible studies investigating the association of the HLA-G 14-bp INS/DEL polymorphism with AID. Our analysis included 11 publications involving a total of 6462 individuals. Overall, no significant association between the HLA-G 14-bp INS/DEL polymorphism and AID was detected in any comparison model. Further subgroup analyses based on AID types and ethnicity also revealed no significant associations. Our results suggest that the HLA-G 14-bp INS/DEL polymorphism is unrelated to the development of AID. Further studies including larger sample sizes are warranted to confirm these results.

Multiple displacement amplification for preimplantation genetic diagnosis of fragile X syndrome.

Preimplantation genetic diagnosis (PGD) has become an assisted reproductive technique for couples that have genetic risks. Despite the many advantages provided by PGD, there are several problems, including amplification failure, allele drop-out and amplification inefficiency. We evaluated multiple displacement amplification (MDA) for PGD of the fragile X syndrome. Whole genome amplification was performed using MDA. MDA products were subjected to fluorescent PCR of fragile X mental retardation-1 (FMR1) CGG repeats, amelogenin and two polymorphic markers. In the pre-clinical tests, the amplification rates of the FMR1 CGG repeat, DXS1215 and FRAXAC1 were 84.2, 87.5 and 75.0%, respectively, while the allele dropout rates were 31.3, 57.1 and 50.0%, respectively. In two PGD treatment cycles, 20 embryos among 30 embryos were successfully diagnosed as 10 normal embryos, four mutated embryos and six heterozygous carriers. Three healthy embryos were transferred to the uterus; however, no clinical pregnancy was achieved. Our data indicate that MDA and fluorescent PCR with four loci can be successfully applied to PGD for fragile X syndrome. Advanced methods for amplification of minuscule amounts of DNA could improve the sensitivity and reliability of PGD for complicated single gene disorders.