von Zons P, Crowley-Nowick P, Friberg D, Bell M, Koldovsky U, Whiteside T L
Department of Obstetrics/Gynecology, University of Dusseldorf, Germany.
Clin Diagn Lab Immunol. 1997 Mar;4(2):202-7. doi: 10.1128/cdli.4.2.202-207.1997.
Natural killer (NK) and lymphokine-activated killer (LAK) cell activities were measured in peripheral blood obtained from healthy women to compare a standard 51Cr release assay with a nonradioactive europium (Eu3+) release assay based on time-resolved fluorescence. The two types of cytotoxicity assays were first compared in paired determinations performed on 28 samples of peripheral blood mononuclear cells obtained from healthy women who had normal pap smears or no biopsy evidence of cervical squamous intraepithelial lesions (SIL). Target cells (NK-sensitive K562 and NK-resistant Raji cell lines) were labeled with Eu3+ only, 51Cr only, or both labels and compared in cytotoxicity assays using fresh or interleukin 2 (IL-2)-activated effector cells. Spontaneous release in the Eu3+ release assay was comparable to that observed in the 51Cr release assay, but maximum Eu3+ release always exceeded that of 51Cr. In 4-h assays, specific release of Eu3+ from target cells was more rapid than that of 51Cr, consistently resulting in 30 to 40% higher levels of activity. However, a significant linear correlation (P < 0.001) was observed between cytotoxicity levels based on measurements of Eu3+ and 51Cr release in 4-h assays. The Eu3+ release assay was then used to measure NK and LAK activities in the peripheral blood of women with cervical SIL or cervical squamous cell carcinoma (SCC). Mean NK activity of women with advanced SIL (121 lytic units [LU]) or SCC (93 LU) was found to be similar to that of controls (101 LU) or patients with normal cervical biopsies (90 LU), as was the ability to generate IL-2-stimulated NK activity. However, LAK activity during 18 h of incubation in the presence of IL-2 was reduced in patients with cervical SCC (P < 0.05) compared with that in normal controls. Results of 51Cr assays performed in parallel with patient samples gave comparable results. Advantages of EU3+ release assays for routine evaluation of cytotoxicity are discussed.
检测了健康女性外周血中的自然杀伤（NK）细胞和淋巴因子激活的杀伤（LAK）细胞活性，以比较标准的51Cr释放试验与基于时间分辨荧光的非放射性铕（Eu3+）释放试验。首先在对28份外周血单个核细胞样本进行的配对测定中比较了这两种细胞毒性试验，这些样本取自巴氏涂片正常或无宫颈鳞状上皮内病变（SIL）活检证据的健康女性。靶细胞（NK敏感的K562细胞系和NK抗性的Raji细胞系）仅用Eu3+、仅用51Cr或同时用两种标记物进行标记，并在使用新鲜或白细胞介素2（IL-2）激活的效应细胞的细胞毒性试验中进行比较。Eu3+释放试验中的自发释放与51Cr释放试验中观察到的相当，但Eu3+的最大释放量总是超过51Cr。在4小时试验中，靶细胞中Eu3+的特异性释放比51Cr更快，活性水平始终高出30%至40%；然而，在4小时试验中，基于Eu3+和51Cr释放测量的细胞毒性水平之间观察到显著的线性相关性（P<0.001）。然后使用Eu3+释放试验测量患有宫颈SIL或宫颈鳞状细胞癌（SCC）的女性外周血中的NK和LAK活性。发现患有高级别SIL（121个溶解单位[LU]）或SCC（93 LU）的女性的平均NK活性与对照组（101 LU）或宫颈活检正常的患者（90 LU）相似，产生IL-2刺激的NK活性的能力也是如此。然而，与正常对照组相比，宫颈SCC患者在IL-2存在下孵育18小时期间的LAK活性降低（P<0.05）。与患者样本并行进行的51Cr试验结果给出了可比的结果。讨论了Eu3+释放试验在细胞毒性常规评估中的优点。
