[Establishment and evaluation of quantitative analysis method for donor chimerism of mice]

This study was aimed to explore the effectiveness of sequential and quantitative detection method for analysing donor chimerism (DC). In order to simulate a mouse model of haploidentical stem cell transplantation, C57BL/6 male mice were used as donors, while CB6F1 female mice were used as recipients and were divided into 2 groups. The two groups of recipients were irradiated with 2 Gy and 6 Gy from (⁶⁰CO gamma-ray source respectively, and then were inoculated intravenously with bone marrow cells (BMCs) and spleen mononuclear cells (SPMNCs). Quantitative analyses of DC were performed with real-time PCR or flow cytometry (FCM) on different days after transplantation. The results showed that real-time PCR and FCM both have advantages and disadvantages in the detection of DC. When DC amount in group of 6 Gy was > 90% with stable macrochimerism for more than 3 months, the efficacy of detection by FCM was well; while the DC amount in group of 2 Gy was below 10% and gradually transformed to different forms of microchimerism until disappeared, in which condition the use of real time-PCR was more appropriate. It is concluded that FCM can detect macrochimerism with high accuracy but would fail when DC amount is less than 1% due to sensitivity limitation, while the real time-PCR is more sensitive for detecting microchimerism but lack of accuracy for detecting macrochimerism. Combination of the two methods can afford sensitive and accurate tool for quantitative analysis of chimerism in mouse model of transplantation and adoptive immunotherapy.