免疫磁珠法检测外周血微转移前列腺癌细胞的方法学探讨

The methodological application of immunomagnetic beads for the detection of circulating prostate cancer cells from micrometastases

目的:探讨前列腺癌外周血微转移免疫磁珠检测方法学的建立及其意义。方法:体外培养前列腺癌LNCaP细胞,将其分别与外周血单个核细胞(PBMC)及全血细胞混合,混合细胞悬液和事先已与单克隆抗体(鼠抗人PSMA单抗)预孵育的包被人抗鼠IgG抗体的磁珠作用,在磁架上分离,显微镜观察,计算玫瑰花环形成率,并进行灵敏度的检测。台盼蓝染色检测分选前后癌细胞存活率。结果:免疫磁珠检测法敏感性高,当PBMC与LNCaP细胞比例为106:1时可以检测到癌细胞,检测灵敏度为20个肿瘤细胞/mL外周血。分选后癌细胞活率较之分选前未明显改变。结论:免疫磁珠法是一种简便、快速、灵敏并且临床实用价值高的检测技术,可为临床早期发现前列腺癌微小残留提供新的思路,有助于前列腺癌的治疗和预后判断。

Objective To explore the establishment of immunomagnetic bead-based technique for the detection of circulating prostate cancer cells from micrometastases and its significance. Methods The prostate cancer cell line LNCaP was cultured in vitro and then mixed with peripheral blood mononuclear cells （PBMCs） and whole hemocytes. The mixed cell suspension was incubated with the immunomagnetic beads coated with human anti-mouse IgG antibodies and which had pre-coated by the mouse anti-human prostate specific membrane antigen monoclonal antibody. The cells were observed microscopically after isolation in the magnet, the rate of rosette formation was calculated, and then the sensitivity of the technique was evaluated. The cell vitality before and after sorting was measured by trypanblau staining. Results This technique was highly sensitive and it could detect cancer cells under the conditions of the PBMC-to-LNCaP ratio being 106 to 1 with a detection rate of 20 cells per ml peripheral blood. No marked change in the cell vitality occurred after sorting. Conclusion Immunomagnetic bead-based technique is a simple, rapid, sensitive, valuable approach and it can identify the residual trace of prostate cancer earlier, which is helpful in the treatment of the malignancy and in the prediction of prognosis.