[The influence of peripheral blood sample storage and delivery on the quantitative detection result of BCR-ABL (P210) transcript levels].

Objective: To explore the influence of storage and delivery conditions of the peripheral blood samples from patients with chronic myeloid leukemia (CML) on the real-time quantitative PCR (RQ-PCR) detection of the BCR-ABL (P210) transcript levels. Methods: The peripheral blood samples of 84 CML patients were collected. The same sample was divided into different groups according to storage time (0, 6, 12, 24, 48, and 72 h) , temperature (room temperature, 18-24 ℃; low temperature, 2-8 ℃) , and vibration conditions (3, 6, and 12 h) . RQ-PCR was used to detect BCR-ABL (P210) transcript levels of the different groups. This study logarithmically transformed (log(10N)) the original data [BCR-ABL copy number, ABL copy number, and BCR-ABL (P210) transcript levels]. Results: ①Agarose gel electrophoresis showed significant RNA degradation of samples after storage for 48 and 72 h at room temperature. ②Among the overall samples, the BCR-ABL copy number of the samples stored at room temperature for 48 and 72 h was significantly lower than that of the samples stored at low temperature (P<0.05) . However, the BCR-ABL (P210) transcript levels had no significant difference between samples stored at low temperature and room temperature. ③No significant changes were noted in the BCR-ABL (P210) transcript levels at different storage times (6, 12, 24, 48, and 72 h) regardless of storage temperature (P>0.05) compared with that at baseline (0 h, -0.56±1.51) . ④ The BCR-ABL copy number of the overall sample only decreased significantly (P<0.05) at 48 h (2.93±1.59) and 72 h (2.79±1.42) compared with that at baseline (0 h, 3.35±1.60) when stored at room temperature. The ABL copy number in the overall sample decreased significantly at 48 and 72 h (whether low and room temperature; P<0.05) . However, no significant changes were noted in the BCR-ABL (P210) transcript levels after vibration for 3 h (-1.29±1.81) , 6 h (-1.24±1.72) , and 12 h (-1.18±1.68; P>0.05) compared with that at baseline (0 h, -0.60±1.37) . Conclusion: Sample storage time, storage temperature, and vibration can interfere with the results of BCR-ABL and ABL copy number but have no significant effect on the quantitative determination of BCR-ABL (P210) transcript levels. This study provides strong support for the feasibility of transregional transportation of peripheral blood samples from patients with CML.

[The establishment and application of internal quality control system for real-time quantitative PCR detection of BCR-ABL (P210) transcript levels].

Objective: To set internal quality control system of BCR-ABL (P210) transcript levels for real-time quantitative PCR (RQ-PCR). Methods: Using K562 cells and HL-60 cells, we prepared high- and low-level BCR-ABL internal quality control substance. The BCR-ABL (P210) transcript levels of internal quality control substance have been determined for 184 times together with clinical samples from August 2013 to October 2015. The slope rate, intercept and correlation coefficient of standard curve were calculated according to different reagent lots (lots number 20130303, 20131212, 20140411 and 20150327 are called R1、R2、R3 and R4 for short respectively), and the detection results of quality control substance were calculated according to different reagent lots and quality control substance lots (lots number 20130725, 20140611 are called Q1、Q2 for short respectively). Then the results were analyzed by Levey-Jennings quality control chart combined with Westgard multi-rules theory. Results: ①We analyzed the slope rate and intercept of standard curve. Fifty-three times of the R1 reagent detection, 80 times of the R3 reagent detection and 14 times of the R4 reagent detection were all under control. For 37 times detection of R2 reagent, the slope rate was out of control for 6 times. It was lower than x-s for the 2-8 tests and upper the average for the 12-37 tests. The intercept was out of control for 9 times, upper the x+s for the 1-8 tests and lower the average for the 12-37 tests. ② According to the detection results of quality control substance, for Q1 quality control substance, 49 tests by R1 reagent were under control, and 1 out of 23 tests by R2 reagent was out of control. For Q2 quality control substance, 14 tests by R2 reagent detection, 72 tests by R3 reagent detection and 14 tests by R4 reagent were all under control. Conclusion: The preparation of high- and low-level quality control substance using K562 and HL-60 cells was convenient and the detection results were reliable and stable. The application of quality control substance combined with slope rate and intercept in the internal quality control may contribute to quality assurance for quantitative detection of BCR-ABL (P210) transcript levels.