Abstract:
While stem cell-based therapies to address both hard and soft tissue regeneration have shown great promise in the pig model, the lack of stem cell reagents in the pig model makes it difficult analyze stem cell populations used in this research. CD34 is widely used as a clinical marker for a subset of cells greatly enriched in hematopoietic stem cells. This marker is also associated with other stem and progenitor cells derived from adipose, endothelial progenitor cells, and skeletal muscle satellite cells. While variations in the CD34 sequence have been well studied in human and mouse, little work has been done to characterize variations in porcine CD34. We used mRNA from a single Yorkshire pig to amplify and sequence the open reading frame of porcine CD34. Using genomic DNA, the alternatively spliced Exon X was characterized. Based on sequencing of the first animal, PCR products were generated from the genomic DNA of 8 unrelated animals from each of the Sinclair, Hanford, and Yucatan minipig breeds. The frequency of single nucleotide polymorphisms (SNPs) in this sampling group was determined by sequencing the PCR products. A total of 15 SNPs were identified in exons 2, 3, 7, and 8 from the 25 animals tested. Of these SNPs, 8 resulted in changes in amino acid sequence. Three changes resulted in hydrophobic/polar shifts, one change resulted in a negative charge/polar shift, and one change alters a potential N-linked glycosylation site. Knowledge of potential variations in the translated CD34 protein will aid in the development of porcine stem cell reagents.