Research Division, Federal Institute for Drugs and Medical Devices (BfArM), Bonn, Germany.
Department of Dermatology and Allergy, University Hospital Aachen, Aachen, Germany.
J Immunol Methods. 2023 Aug;519:113515. doi: 10.1016/j.jim.2023.113515. Epub 2023 Jun 16.
The lymphocyte transformation test (LTT) is used for the in vitro detection of a drug sensitization in assumed drug allergic patients. It is based on the detection of antigen (drug)-specific activation of T cells indicated by e.g. proliferation or cytokine secretion. However, occasional stimulatory effects of the drug unrelated to specific drug-allergic mechanisms can only be detected if a larger number of non-drug allergic control persons are tested with this specific drug. In this respect, the overall specificity of the LTT with ELISA read-out is summarized in several review articles, but the impact of a specific drug on the specificity has not yet been analyzed in a larger set of control persons.
Do amoxicillin, cefuroxime and clindamycin induce an interferon (IFN)-y or interleukin (IL)-5 secretion of PBMC from control persons using the LTT with ELISA read-out?
We performed LTTs with amoxicillin, cefuroxime and clindamycin and determined drug-specific IFN-γ and IL-5 secretion measured by ELISA read-out. We included PBMC from 60 non-drug allergic control persons, who were unexposed to the tested drug at the time of blood donation.
PBMC from 12 out of 23 control persons tested with amoxicillin gave a positive stimulation index (SI > 3.0) for IFN-γ resulting in a specificity of 47.8%. The corresponding specificity was 75% for cefuroxime (5/20 if SI > 3.0) and 58.8% for clindamycin (7/17, if SI > 2.0), respectively. In a next step, we calculated the Δ IFN-γ concentration by subtracting the background IFN-γ concentration in the unstimulated sample from the stimulated sample. After stimulation with amoxicillin, a mean concentration of 21.0 pg/mL IFN-γ was secreted. The less outlier prone median concentration was 7.4 pg/mL and much higher than for cefuroxime (1.7 pg/mL) and clindamycin (1.0 pg/mL). Remarkably, IL-5 concentrations were below the detection limit (< 1 pg/mL) for all drugs in all control persons who responded to TT.
Consideration of these observations may be helpful since a positive LTT result in a control patient may challenge the validity of a positive LTT result in the same experiment for a patient with assumed drug allergy.
淋巴细胞转化试验（LTT）用于体外检测疑似药物过敏患者的药物致敏。它基于检测抗原（药物）特异性激活 T 细胞，例如通过增殖或细胞因子分泌来指示。然而，如果用这种特定药物测试更多的非药物过敏对照者，则只能检测到与特定药物过敏机制无关的偶尔的药物刺激作用。在这方面，用 ELISA 读取的 LTT 的总体特异性在几篇综述文章中进行了总结，但尚未在更大的对照人群中分析特定药物对特异性的影响。
用 ELISA 读取的 LTT 检测阿莫西林、头孢呋辛和克林霉素是否会诱导对照者的外周血单核细胞（PBMC）产生干扰素（IFN）-γ或白细胞介素（IL）-5 分泌？
我们用阿莫西林、头孢呋辛和克林霉素进行了 LTT，并通过 ELISA 读取来测定药物特异性 IFN-γ 和 IL-5 分泌。我们包括了 60 名非药物过敏对照者的 PBMC，他们在献血时未接触过测试药物。
在 23 名接受阿莫西林测试的对照者中，有 12 名的干扰素（IFN）-γ刺激指数（SI>3.0）呈阳性，特异性为 47.8%。头孢呋辛的相应特异性为 75%（SI>3.0 时为 5/20），克林霉素为 58.8%（SI>2.0 时为 7/17）。在下一步中，我们通过从刺激样本中减去未刺激样本中的 IFN-γ 背景浓度来计算 Δ IFN-γ 浓度。用阿莫西林刺激后，分泌的 IFN-γ 平均浓度为 21.0 pg/mL。较少异常值的中位数浓度为 7.4 pg/mL，明显高于头孢呋辛（1.7 pg/mL）和克林霉素（1.0 pg/mL）。值得注意的是，在所有对 TT 有反应的对照者中，所有药物的 IL-5 浓度均低于检测限（<1 pg/mL）。
考虑到这些观察结果可能会有所帮助，因为在疑似药物过敏患者的同一实验中，对照者的 LTT 阳性结果可能会对 LTT 阳性结果的有效性提出质疑。
