KLF DNA-Binding ELISA Kit

Blood transfusion is widely used in the clinic but the source of red blood cells (RBCs) is dependent on donors, procedures are susceptible to transfusion-transmitted infections and complications can arise from immunological incompatibility. Clinically-compatible and scalable protocols that allow the production of RBCs from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) have been described but progress to translation has been hampered by poor maturation and fragility of the resultant cells. Genetic programming using transcription factors has been used to drive lineage determination and differentiation so we used this approach to assess whether exogenous expression of the Erythroid Kr_ uppel-like factor 1 (EKLF/ KLF1) could augment the differentiation and stability of iPSC-derived RBCs. To activate KLF1 at defined time points during later stages of the differentiation process and to avoid transgene silencing that is commonly observed in differentiating pluripotent stem cells, we targeted a tamoxifen-inducible KLF1-ERT2 expression cassette into the AAVS1 locus. Activation of KLF1 at day 10 of the differentiation process when hematopoietic progenitor cells were present, enhanced erythroid commitment and differentiation. Continued culture resulted the appearance of more enucleated cells when KLF1 was activated which is possibly due to their more robust morphology. Globin profiling indicated that these conditions produced embryonic-like erythroid cells. This study demonstrates the successful use of an inducible genetic programing strategy that could be applied to the production of many other cell lineages from human induced pluripotent stem cells with the integration of programming factors into the AAVS1 locus providing a safer and more reproducible route to the clinic.

BACKGROUND: The distribution of RBC antigens, which define blood group types, differs among populations. In contrast to many world populations, blood group profiles for Indigenous Australians have not been well studied. As it is now possible to predict comprehensive blood group antigen profiles from genomic data sets, we aimed to apply this for Indigenous Australians and to provide a comparison to other major world populations. STUDY DESIGN AND METHODS: Whole exome sequence data for 72 Western Desert Indigenous Australians was provided by the Telethon Kids Institute. Variants (against hg19) were annotated using computer software (ANNOVAR, Qiagen Bioinformatics) and filtered to include only variants in genes for 36 blood group systems, and the transcription factors KLF1 and GATA1. The RHCE*C allele and RHD zygosity were identified by copy number variant analysis of sequence alignments. The impact of missense variants was investigated in silico using a meta-predictor of disease-causing variants (Meta-SNP). RESULTS: For 21 blood group systems the predicted blood group antigen frequencies were comparable to those for other major world populations. For 13 systems, interesting points of contrast were identified. Furthermore, we identified 12 novel variants, one novel D allele, and four rare variants with potential clinical significance. CONCLUSION: This is the first systematic assessment of genomic data to elucidate blood group antigen profiles for Indigenous Australians who are linguistically and culturally diverse. Our study paves the way to understanding the geographic distribution of blood group variants in different Indigenous groups and the associated RBC phenotypes. This in turn is expected to guide transfusion practice for Indigenous individuals.