Zhang Binshan, Wu Yunqi, Wang Zhongli, Gao Suhua, Liu Hongyan, Lin Yao, Yu Pei
National Health Commission (NHC) Key Lab of Hormones and Development and Tianjin Key Lab of Metabolic Diseases, Tianjin Medical University Chu Hsien-I Memorial Hospital & Institute of Endocrinology, Tianjin, China.
Department of Nephrology & Blood Purification Center, The Second Hospital of Tianjin Medical University, Tianjin, China.
Front Immunol. 2025 Feb 19;16:1521554. doi: 10.3389/fimmu.2025.1521554. eCollection 2025.
Chronic inflammation and immune imbalance mediated by macrophages are considered pivotal in diabetic kidney disease (DKD). The study aims to clarify the macrophage heterogeneity and phenotype dynamics, and pinpoint critical targets within efferocytosis in DKD.
Utilizing early human DKD sequencing data, we computed the potential communication between leukocytes and renal intrinsic cells. Subsequently, we scrutinized the single-cell RNA sequencing (scRNA-seq) data from CD45-enriched immune cells, concentrating on the macrophage subsets in DKD. Pseudotime trajectory analysis was conducted to explore cell development. Differential expression genes (DEGs) from macrophage subgroups and bulk RNA-sequencing were used to identify shared hub genes. The NephroseqV5 platform was employed to evaluate the clinical significance, and the expression of key molecules was validated in DKD tissues.
Macrophage infiltration rose in DKD, causing inflammation through the release of chemokines. As time progressed, the number of resident macrophages substantially dropped, with diminishing M1-like and increasing M2-like phenotypes relative to early stages. Further analysis pointed to the most enrichment of macrophage function is the phagosome. We overlapped the DEGs with efferocytosis-related genes and identified key genes, including CD36, ITGAM, and CX3CR1, which exhibited significant correlations with macrophages and T cells. The Nephroseq database revealed that they are associated with proteinuria and renal function. Consistent with the validation set, experiments verified elevated expression levels of key molecules.
In essence, our research elucidated the dynamics in macrophage subtype transitions. It emphasized three pivotal genes as critical modulators of macrophage efferocytosis in DKD, indicating their potential as innovative biomarkers and therapeutic targets.
巨噬细胞介导的慢性炎症和免疫失衡被认为在糖尿病肾病（DKD）中起关键作用。本研究旨在阐明巨噬细胞的异质性和表型动态变化，并确定DKD中胞葬作用的关键靶点。
利用早期人类DKD测序数据，我们计算了白细胞与肾固有细胞之间的潜在通讯。随后，我们仔细研究了来自富集CD45的免疫细胞的单细胞RNA测序（scRNA-seq）数据，重点关注DKD中的巨噬细胞亚群。进行了伪时间轨迹分析以探索细胞发育。来自巨噬细胞亚群和批量RNA测序的差异表达基因（DEG）用于识别共享的枢纽基因。使用NephroseqV5平台评估临床意义，并在DKD组织中验证关键分子的表达。
DKD中巨噬细胞浸润增加，通过趋化因子的释放引起炎症。随着时间的推移，驻留巨噬细胞的数量大幅下降，与早期相比，M1样表型减少，M2样表型增加。进一步分析表明巨噬细胞功能最丰富的是吞噬体。我们将DEG与胞葬作用相关基因重叠并鉴定出关键基因，包括CD36、ITGAM和CX3CR1，它们与巨噬细胞和T细胞表现出显著相关性。Nephroseq数据库显示它们与蛋白尿和肾功能相关。与验证集一致，实验验证了关键分子的表达水平升高。
本质上，我们的研究阐明了巨噬细胞亚型转变的动态变化。它强调了三个关键基因作为DKD中巨噬细胞胞葬作用的关键调节因子，表明它们作为创新生物标志物和治疗靶点的潜力。
