Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Mexico City 14080, Mexico.
Institute for Clinical Chemistry, University of Heidelberg Medical Faculty Mannheim, D-68167 Mannheim, Germany.
Cells. 2022 May 13;11(10):1635. doi: 10.3390/cells11101635.
In recent years, a growing body of evidence has shown the presence of a subpopulation of macrophages that express CD3, especially in the context of mycobacterial infections. Despite these findings, the function of these cells has been poorly understood. Furthermore, the low frequency of CD3+ macrophages in humans limits the study of this subpopulation. This work aimed to evaluate the expression of CD3 in a murine macrophage cell line and its potential for the study of CD3 signaling. The murine macrophage cell line RAW was used to evaluate CD3 expression at the transcriptional and protein levels and the effect of in vitro infection with the (BCG) on these. Our data showed that RAW macrophages express CD3, both the ε and ζ chains, and it is further increased at the transcriptional level after BCG infection. Furthermore, our data suggest that CD3 can be found on the cell surface and intracellularly. However, this molecule is internalized constantly, mainly after activation with anti-CD3 stimulus, but interestingly, it is stably maintained at the transcriptional level. Finally, signaling proteins such as NFAT1, c-Jun, and IKK-α are highly expressed in RAW macrophages. They may play a role in the CD3-controlled signaling pathway to deliver inflammatory cytokines such as TNF and IL-6. Our study provides evidence to support that RAW cells are a suitable model to study the function and signaling of the CD3 complex in myeloid cells.
近年来，越来越多的证据表明存在表达 CD3 的巨噬细胞亚群，特别是在分枝杆菌感染的情况下。尽管有这些发现，但这些细胞的功能仍知之甚少。此外，人类中 CD3+巨噬细胞的频率较低，限制了对该亚群的研究。本工作旨在评估 CD3 在鼠源巨噬细胞系中的表达及其在 CD3 信号研究中的潜力。使用鼠源巨噬细胞系 RAW 来评估 CD3 在转录和蛋白水平上的表达，并评估体外感染结核分枝杆菌（BCG）对这些表达的影响。我们的数据表明，RAW 巨噬细胞表达 CD3，包括 ε 和 ζ 链，并且在 BCG 感染后转录水平进一步增加。此外，我们的数据表明 CD3 可以存在于细胞表面和细胞内。然而，该分子不断内化，主要在通过抗 CD3 刺激激活后，但有趣的是，它在转录水平上稳定维持。最后，NFAT1、c-Jun 和 IKK-α 等信号蛋白在 RAW 巨噬细胞中高度表达。它们可能在 CD3 控制的信号通路中发挥作用，以产生 TNF 和 IL-6 等炎症细胞因子。我们的研究提供了证据支持 RAW 细胞是研究髓样细胞中 CD3 复合物功能和信号的合适模型。
