Background: Type 2 innate lymphoid cells (ILC2s) have emerged as key players in the development of type 2 driven diseases such as allergy and asthma. Due to their low number in the circulation, in vitro expansion is needed to unravel their mechanisms of action.
Purpose: The aim of this study is to assess the impact of different culture conditions and address whether the method of expansion may distinctly affect healthy donor or patient-derived ILC2s.
Methods: Here, we described the impact of six different culture conditions on the proliferation, phenotype and function of human ILC2s freshly obtained from healthy donors (healthy ILC2s) and allergic patients (patient ILC2s).
Results: We showed that the cytokine cocktail or the PHA induced the highest proliferation of healthy ILC2s and patient ILC2s, respectively. We observed that the stromal cells OP9, used as ILC2 feeders, did not boost their proliferation, but impaired the activation marker expression and the function of patient ILC2s. Furthermore, we demonstrated that the culture conditions differently impacted the activation state of c-Kit^high and c-Kit^low ILC2s, in both healthy donors and allergic patients. Last, we also observed that ILC2s expanded only with IL-2 and IL-7 were the most prone to secrete IL-5 and IL-13 upon IL-33 stimulation. In contrast, in patients, the addition of OP9 cells during the expansion restrained their type 2 cytokine secretory functions.
Conclusion: This report highlights that culture conditions distinctly impacted on the healthy or patient ILC2 behavior, with important consequences for their study in disease settings.



中文翻译：

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健康和患者的 2 型先天淋巴细胞受体外培养条件的不同影响

背景： 2 型先天淋巴细胞 (ILC2) 已成为 2 型驱动疾病（如过敏和哮喘）发展的关键参与者。由于它们在循环中的数量很少，因此需要体外扩增来揭示它们的作用机制。
目的：本研究的目的是评估不同培养条件的影响，并确定扩增方法是否可能明显影响健康供体或患者衍生的 ILC2。
方法：在这里，我们描述了六种不同培养条件对从健康供体（健康 ILC2）和过敏患者（患者 ILC2）新鲜获得的人类 ILC2 的增殖、表型和功能的影响。
结果：我们发现细胞因子混合物或 PHA 分别诱导了健康 ILC2 和患者 ILC2 的最高增殖。我们观察到，用作 ILC2 饲养层的基质细胞 OP9 并没有促进它们的增殖，但会损害激活标志物的表达和患者 ILC2 的功能。此外，我们证明了培养条件对健康供体和过敏患者的 c-Kit^高和 c-Kit^低ILC2 的激活状态有不同的影响。最后，我们还观察到仅用 IL-2 和 IL-7 扩增的 ILC2 在 IL-33 刺激下最容易分泌 IL-5 和 IL-13。相反，在患者中，在扩增过程中添加 OP9 细胞会抑制其 2 型细胞因子分泌功能。
结论：本报告强调了培养条件对健康或患者 ILC2 行为的显着影响，对他们在疾病环境中的研究产生了重要影响。