Performance of a novel eight-color flow cytometry panel for measurable residual disease assessment of chronic lymphocytic leukemia.

BACKGROUND: Measurable residual disease (MRD) is an important prognostic indicator of chronic lymphocytic leukemia (CLL). Different flow cytometric panels have been developed for the MRD assessment of CLL in Western countries; however, the application of these panels in China remains largely unexplored. METHODS: Owing to the requirements for high accuracy, reproducibility, and comparability of MRD assessment in China, we investigated the performance of a flow cytometric approach (CD45-ROR1 panel) to assess MRD in patients with CLL. The European Research Initiative on CLL (ERIC) eight-color panel was used as the "gold standard." RESULTS: The sensitivity, specificity, and concordance rate of the CD45-ROR1 panel in the MRD assessment of CLL were 100% (87/87), 88.5% (23/26), and 97.3% (110/113), respectively. Two of the three inconsistent samples were further verified using next-generation sequencing. In addition, the MRD results obtained from the CD45-ROR1 panel were positively associated with the ERIC eight-color panel results for MRD assessment (R = 0.98, p < 0.0001). MRD detection at low levels (≤1.0%) demonstrated a smaller difference between the two methods (bias, -0.11; 95% CI, -0.90 to 0.68) than that at high levels (>1%). In the reproducibility assessment, the bias was smaller at three data points (within 24, 48, and 72 h) in the CD45-ROR1 panel than in the ERIC eight-color panel. Moreover, MRD levels detected using the CD45-ROR1 panel for the same samples from different laboratories showed a strong statistical correlation (R = 0.99, p < 0.0001) with trivial interlaboratory variation (bias, 0.135; 95% CI, -0.439 to 0.709). In addition, the positivity rate of MRD in the bone marrow samples was higher than that in the peripheral blood samples. CONCLUSIONS: Collectively, this study demonstrated that the CD45-ROR1 panel is a reliable method for MRD assessment of CLL with high sensitivity, reproducibility, and reliability.

Cryotherapy: A Novel Method for Virus Eradication in Economically Important Plant Species.

Virus diseases have been a great threat to production of economically important crops. In practice, the use of virus-free planting material is an effective strategy to control viral diseases. Cryotherapy, developed based on cryopreservation, is a novel plant biotechnology tool for virus eradication. Comparing to the traditional meristem culture for virus elimination, cryotherapy resulted in high efficiency of pathogen eradication. In general, cryotherapy includes seven major steps: (1) introduction of infected plant materials into in vitro cultures, (2) shoot tip excision, (3) tolerance induction of explants to dehydration and subsequent freezing in liquid nitrogen (LN), (4) a short-time treatment of explants in LN, (5) warming and post-culture for regeneration, (6) re-establishment of regenerated plants in greenhouse conditions, and (7) virus indexing.

Assessment of clonality in T-cell large granular lymphocytic leukemia: flow cytometric T cell receptor Vß repertoire and T cell receptor gene rearrangement.

The usefulness of flow cytometric variable ß-chain repertoire (FC-Vß) and T-cell receptor gene rearrangement (TCR-GR) analyses for differentiating T-cell large granular lymphocytic leukemia (T-LGLL) from reactive T-large granular lymphocyte (T-LGL) lymphocytosis has been insufficiently studied to date. In this study, we analyzed the diagnostic value of TCR-GR and FC-Vß analysis in T-LGLL, and compared these results. In our study, FC-Vß analysis was positive in all cases of T-LGLL, and clonality assessment of FC-Vß had equal sensitivity and specificity to GeneScanning analysis but was more sensitive than heteroduplex analysis. Suspected T-cell clonality can best be addressed by evaluating two TCR targets (TCRß and TCRγ), either in parallel or consecutively. Signal transducer and activator of transcription 3 (STAT3) mutation may provide a diagnostic tool for classifying some cases of T-LGL lymphocytosis as true T-LGLL. Our results further demonstrate a significant correlation of STAT3 mutation with pure red cell aplasia, neutropenia, hepatomegaly, ß2-microglobulin and anemia.

Quality assessment of fructus psoraleae.

Two newly-reported benzofuran glycosides, named psoralenoside and isopsoralenoside, along with two major coumarins, psoralen and isopsoralen, were simultaneously determined in twenty-three samples of Fructus Psoraleae collected from different growth areas in China. The quantitative method was validated, and the mean recovery rates from fortified samples (n=5) of psoralenoside, isopsoralenoside, psoralen and isopsoralen, were 96.5%, 97.1%, 100.7%, and 99.3% with variation coefficient of 3.1%, 3.6%, 2.3%, and 2.2%, respectively. An interesting biotransformation relationship between the glycosides and the coumarins was revealed on the basis of the quality analysis results. It was also suggested that psoralenoside and isopsoralenoside should be used as key quality markers for Fructus Psoraleae, together with the commonly used psoralen and isopsoralen.