Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, Canada.
J Biomed Mater Res A. 2017 Sep;105(9):2499-2509. doi: 10.1002/jbm.a.36107. Epub 2017 Jun 6.
Recognition of topographical features induces phenotypic changes in macrophages although the receptors and signaling pathways are not completely characterized. As integrin molecules in focal adhesions/podosomes are in intimate contact with topography and topography modulates the NFkB pathway through cholesterol enriched raft-associated adhesive signaling structures we hypothesized that a cell-surface signaling complex comprised of galectin-3 together with its ligand CD98 and integrinβ1 is important for topography-directed lineage determination. This study used polished, sand blasted and acid etched (SLA) surfaces and two novel grooved topographies (G1 and G2) produced by anisotropic etching of Si <1 1 0> to evaluate the role of galectin-3 in macrophage polarization in RAW 264.7 macrophages, as determined by gene expression and morphology. In the presence of the galectin-3 inhibitor, lactose, the M2 marker (mannose receptor) was down-regulated while the M1 marker (iNOS) was up-regulated on smooth and rough surfaces. This skewing of phenotype suggests a role for galectin-3 in macrophage polarization towards the M2 phenotype. Additionally, we evaluated the role of PI3K on polarization using PI3K inhibitor LY294002. We found that the M2 marker was down-regulated on both PO (surface polished) and G1 surfaces implicating PI3K in lineage determination. We also found that surface topography altered cell morphology; macrophages had a larger area on G2 surfaces. Lactose treatment significantly reduced the cell area on all topographies suggesting that the galectin-3 is also involved in signaling complexes triggering the rearrangement of the actin cytoskeleton. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2499-2509, 2017.
识别地形特征会诱导巨噬细胞表型改变，尽管受体和信号通路尚未完全阐明。由于粘着斑/伪足中的整合素分子与地形密切接触，而地形通过富含胆固醇的筏状粘着信号结构来调节 NFkB 途径，我们假设由半乳糖凝集素-3与其配体 CD98 和整合素β1 组成的细胞表面信号复合物对于地形导向的谱系决定很重要。本研究使用抛光、喷砂和酸蚀（SLA）表面以及通过 Si <1 1 0>各向异性蚀刻产生的两种新型槽形形貌（G1 和 G2）来评估半乳糖凝集素-3在 RAW 264.7 巨噬细胞中极化的作用，通过基因表达和形态来确定。在半乳糖凝集素-3抑制剂乳糖存在的情况下，光滑和粗糙表面上的 M2 标志物（甘露糖受体）下调，而 M1 标志物（iNOS）上调。这种表型的倾斜表明半乳糖凝集素-3在巨噬细胞向 M2 表型极化中起作用。此外，我们使用 PI3K 抑制剂 LY294002 评估了 PI3K 在极化中的作用。我们发现，PI3K 在 PO（表面抛光）和 G1 表面上都参与了 M2 标志物的下调，暗示了 PI3K 在谱系决定中的作用。我们还发现，表面形貌改变了细胞形态；巨噬细胞在 G2 表面上的面积更大。乳糖处理显著降低了所有形貌上的细胞面积，表明半乳糖凝集素-3也参与了触发肌动蛋白细胞骨架重排的信号复合物。© 2017 威利父子公司。J 生物医学材料研究部分 A：105A：2499-2509，2017 年。
