Isolation of CD133 positive bladder cancer cells with magnetic cell sorting system and research on the biological characteristics

Abstract

Objective To isolate CD133 positive cell from bladder cancer cell line 5637 with magnetic cell sorting system (MACS) and to study the different biological characteristics of CD133+ and CD133 cells.Methods Flow cytometry was used to determine the proportion of CD133 + cells sorted by magnetic-activated cell sorting in the bladder cancer cell line 5637.The biological characteristics of CD133 + and CD133-cells was studied by methyl thiazol tetrazolium (MTT) assay,Flat colony formation,Wound healing assay and differentiation ability.Results The proportion of CD133 + cells in the bladder cancer cell line 5637 was 1.45％,which was determined by flow cytometry.CD133 + cells purified by MACS were in a considerable purity of 93.42％.The proliferation and migration capacity of CD133 + cells display stronger than that of CD133-cells and non-separated tumor cells (P ＜0.05).The formation rate of colony sphere in CD133+ group [(89.333 ± 4.530)％] was higher than that in CD133-group [(22.667 ± 4.041)％,P ＜ 0.05].After two days culturing in serum-containing medium,the percentage of CD133 + cell population decreased rapidly to 48.19％ as detected by flow cytometer.After four days culturing in serum-containing medium,there was no obvious difference of the purity comparing with that before sorting.Conclusion CD133 + cells could be effectively obtained by MACS; CD133 + cells showed stem cell-like properties of self-renewal and differentiation compared with the CD133 cells in vitro. Key words: Bladder neoplasms; Cancer stem cells; Magnetic cell sorting; CD133