National AIDS Research Institute (ICMR), Pune, India.
Indian J Med Res. 2013 Feb;137(2):346-55.
BACKGROUND & OBJECTIVES: Reliable CD4 counts are important for successful implementation of antiretroviral treatment (ART). Availability of dry CD4 reagents can eliminate cold chain requirement reducing shipment and storage cost. An attempt was made in this study to validate the ReaPan and Rea T Count dry reagents developed by ReaMetrix against the original BD Biosciences liquid reagents.
Absolute counts and percentages of CD4, CD8 and CD3 + T cells obtained in 100 HIV infected individuals using the test and reference reagents were analyzed for correlation and agreement using Pearson's correlation and Bland Altman bias analysis . The stability of the reagents and of the stained samples was analyzed at ambient temperature and at 37 °C.
The absolute CD4 + T cell count and percentages obtained using test and reference reagents showed correlation coefficients ranging from 833 to 981. A mean bias between dry and reference reagents ranged from 0.8 to 26.4. The ReaPan and Rea T Count reagents were stable up to one month at 37 °C also. The samples stained with ReaPan reagents were stable at ambient temperature till day 7 whereas the samples stained with Rea T Count reagents were stable at ambient temperature and at 37° C for 10 days.
INTERPRETATION & CONCLUSIONS: The ReaPan dry reagents can be used on existing FACSCalibur machines with additional training on Cell Quest Pro software without incurring any additional equipment cost and this can eliminate the requirement of cold chain during transport and on site storage. The stability of the stained samples has great clinical significance preventing redrawing of the blood samples from the patients.
可靠的 CD4 计数对于成功实施抗逆转录病毒治疗（ART）至关重要。干燥 CD4 试剂的可用性可以消除冷链要求，降低运输和储存成本。本研究试图验证 ReaMetrix 公司生产的 ReaPan 和 Rea T Count 干燥试剂与原始 BD Biosciences 液体试剂的相关性。
使用测试和参考试剂对 100 例 HIV 感染个体的绝对 CD4、CD8 和 CD3+T 细胞计数和百分比进行分析，采用 Pearson 相关分析和 Bland Altman 偏差分析评估相关性和一致性。在环境温度和 37°C 下分析试剂和染色样本的稳定性。
使用测试和参考试剂获得的绝对 CD4+T 细胞计数和百分比的相关系数范围为 833 至 981。干燥试剂与参考试剂之间的平均偏差范围为 0.8 至 26.4。ReaPan 和 Rea T Count 试剂在 37°C 下可稳定保存 1 个月。用 ReaPan 试剂染色的样本在环境温度下可稳定保存至第 7 天，而用 Rea T Count 试剂染色的样本在环境温度和 37°C 下可稳定保存 10 天。
ReaPan 干燥试剂可在现有的 FACSCalibur 仪器上使用，只需对 Cell Quest Pro 软件进行额外培训，无需额外的设备成本，并且可以消除运输和现场储存过程中对冷链的要求。染色样本的稳定性具有重要的临床意义，可防止从患者重新抽取血液样本。
