Establishment of a temperature-sensitive stem cell line and its application in traumatic brain injury patients during hypothemia treatment

Abstract

Objective To establish a temperature-sensitive stem cell line for appropriating cells transplantation in injured brain area during patients accepting hypothermia treatment. Method After transfecting plasmid containing temperature-sensitive simian virus 40 large T-antigen (tsSV40LT) into umbilical cord mesenchymal stem cells (UCMSCs), PCR was used to detect gene integration. Then cell growth curves were drawn in 33℃ and 37℃ respectively. Serum-dependent experimental and soft agar colony assay were used to examine the tumorigenesis of the stem cells. After TBI models in thymic mice were established, the stem cells were transplated into injured area. Proliferating cell nuclear antigen expression and in situ apoptosis were detected by immunofluorescence. Results The tsSV40LT gene was integrated into UCMSCs successfully. When cultured at 33℃ incubator, the new cell line displayed high proliferation activity, strong tolerance to low nutrient conditions, and strong cell clone ability. But when cultured at 37℃ incubator, the cell line showed a converse profile. In vivo, the results showed that the brain tissue during hypothermia treatment more highly expressed PCNA, and existed lower cell apoptosis, than normothermia group. Conclusions The stem cell line modified by tsSV40LT is highly temperature-sensitive, and its proliferation activity can be regulated effectively, and that supports the clinical application of stem cells transplantation into injured brain area during hypothermia treatment. Key words: Craniocerebral trauma; Hypothermia; Stem cells; Cell proliferation