GATA transcription in a small rhodamine 123lowCD34+ subpopulation of a peripheral blood–derived CD34−CD105+ mesenchymal cell line

Objective Based on previous animal experiments that suggest the plasticity of peripheral blood–derived, CD34− stem cell lines, the aim of this study was to isolate CD34− stem cell lines from human peripheral blood cells and obtain evidence of their multipotency and plasticity. Materials and Methods Adherent growing cells were isolated from peripheral blood mononuclear cells from a healthy volunteer donor and different cell clones were established after SV40 large-T-antigen–mediated immortalization. The immunophenotype of the cell lines was investigated by flow cytometry. One particular cell clone, V54/2, was stained with rhodamine 123, and the Rh123low and Rh123high subpopulations were sorted for a reverse transcriptase polymerase chain reaction gene expression survey and distinct differences in morphology and biologic behavior. Results The peripheral blood–derived and fibroblast-like cell line V54/2 expressed high levels of CD10 and CD105 and showed only a very low level expression of CD34 (<1.0%) and CD117 (c-kit). Among the entire CD34−CD105+ cell population that transcribed factors such as Myb, Tie-1, and VEGF, there was a small Rh123lowCD34+ subpopulation that transcribed significant levels of several members of the GATA family of transcription factors. The morphology of the Rh123lowCD34+ (also expressing the P-glycoprotein) was different compared to the Rh123highCD34− population. Mesenchymal differentiation into glial fibrillary acidic protein (GFAP)+ glial cells could be shown from the entire CD34−CD105+ cell population. Conclusions The findings provide evidence that it is possible to isolate CD34−CD105+ mesenchymal stem cell lines from human peripheral blood cells that contain a small subpopulation of CD34+ and GATA-transcribing cells. Those cells are potential hematopoietic progenitors and can be recruited from the CD34− stem cell pool. The plasticity of stem cells seems to require essential molecular tools, such as a panel of transcription factors, to respond to the environmental demand within a biologic system.