Hospital Israelita Albert Einstein, Rua Comendador Elias Jafet, São Paulo 05652-000, Brazil.
Cells. 2022 Dec 16;11(24):4099. doi: 10.3390/cells11244099.
Chemokines are molecules that pertain to a family of small cytokines and can generate cell chemotaxis through the interaction with their receptors. Chemokines can trigger signaling via conventional G-protein-coupled receptors or through atypical chemokine receptors. Currently, four atypical chemokine receptors have been are described (ACKR1, ACKR2, ACKR3 and ACKR4). ACKRs are expressed in various cells and tissues, including T lymphocytes. These receptors' main function is related to the internalization and degradation of chemokines, as well as to the inflammation control. However, the expression of these receptors in human T lymphocytes is unclear in the literature. The objective of this study was to evaluate the expression of ACKRs in different subpopulations of T lymphocytes. For this, peripheral blood from healthy donors was used to analyze the expression of ACKR2, ACKR3 and ACKR4 by immunophenotyping CD4, CD8 T lymphocytes and, in their subsets, naive, transition and memory. Results obtained in this study demonstrated that ACKR2, ACKR3 and ACKR4 receptors were expressed by T lymphocytes subsets in different proportions. These receptors are highly expressed in the cytoplasmic milieu of all subsets of T lymphocytes, therefore suggesting that their expression in plasma membrane is regulated after transcription, and it must be dependent on a stimulus, which was not identified in our study. Thus, regarding ACKRs function as scavenger receptors, at least for the ACKR3, this function does not impair the chemotaxis exert for their ligand compared to the typical counterpart receptor.
趋化因子是一类小分子细胞因子，通过与受体相互作用可以引发细胞趋化。趋化因子可以通过传统的 G 蛋白偶联受体或通过非典型趋化因子受体触发信号转导。目前已经描述了四种非典型趋化因子受体（ACKR1、ACKR2、ACKR3 和 ACKR4）。ACKR 表达于各种细胞和组织中，包括 T 淋巴细胞。这些受体的主要功能与趋化因子的内化和降解以及炎症控制有关。然而，这些受体在人类 T 淋巴细胞中的表达在文献中尚不清楚。本研究旨在评估 ACKR 在 T 淋巴细胞不同亚群中的表达。为此，使用来自健康供体的外周血通过免疫表型分析 CD4、CD8 T 淋巴细胞及其幼稚、过渡和记忆亚群来评估 ACKR2、ACKR3 和 ACKR4 的表达。本研究的结果表明，ACKR2、ACKR3 和 ACKR4 受体在 T 淋巴细胞亚群中以不同的比例表达。这些受体在 T 淋巴细胞所有亚群的细胞质中均高度表达，因此表明其在质膜上的表达是在转录后受到调节的，并且必须依赖于我们研究中未确定的刺激。因此，关于 ACKR 作为清除受体的功能，至少对于 ACKR3 而言，与典型配体受体相比，其趋化作用不会因该功能而受损。
