中国生物工程杂志

Objective: To explore the importance and clinical indications of high-sensitivity assay detecting PNH clones by flow cytometry and the incidence and clinical significance of PNH clones in patients with hematopenia.Methods: FLAER combined with CD24 or CD14 was used to detect the percentage of PNH clones in granulocytes and monocytes, and CD59 was used to detect the percentage of PNH clones in erythrocytes of 20 healthy volunteers and 1 095 patients with hematopenia. Meanwhile, CD59 negative percentage in granulocytes and monocytes of 31 patients was detected by traditional CD59 method.Results: According to background of volunteers and numbers of cells, limited of detection (LOD) of granulocytes, monocytes and erythrocytes were 0.04%, 0.10% and 0.05%, respectively. The median percentages of FLAER ^-CD24 ^- granulocytes, FLAER ^-CD14 ^- monocytes and CD59 ^- erythrocytes were 0.02%, 0.02% and 0.03% in 827 patients, separately. The proportions of PNH clones in granulocytes were above LOD in 318 patients. Among of 180 patients with PNH clones below 1.00%, the consistent rates of granulocytes with monocytes and erythrocytes were from 43% to 45%. When the percentages of PNH clones in granulocytes were more than 1.00%, the consistency rates of granulocytes with monocytes and erythrocytes were around 90.00%. Comparing the percentage of CD59 negative granulocytes and monocytes with that of FLAER and anchor protein double negative, the former was significantly lower than the latter (P< 0.000 1 and P=0.000 9). The percentages of FLAER single negative granulocytes were higher than that of FLAER and anchor protein double negative cells in 26.85% patients. The similar results occured in monocytes of 24.54% patients. The patients with PNH clones below 0.10% were affected more easily. PNH clones were 90.30% (44.49%~99.05%) in 36 patients with PNH and 1.30% (0.10%~96.07%) in 50 patients with MDS or AA, separately (P<0.000 1). When PNH clone was 41.81%, the sensitivity and specificity of PNH diagnosis were 100.0% and 96.0%, respectively. Conclusion: In this study, the LOD of granulocyte and erythrocyte was 0.04% and 0.05% respectively. When the proportion of PNH clones in granulocytes is more than 1.00%, the positive results of monocytes and erythocytes are more consistent. PNH disease is more likely when the proportion of PNH clones is higher than 41.81%.