Abstract Background Dendritic cells (DCs) play vital roles in the development of arteriosclerosis. DCs form a heterogeneous population with various functions among mononuclear cells (MNCs). The use of different markers for DCs and a lack of insight into the mechanisms in previous studies have resulted in inconsistent findings regarding whether DCs promote or inhibit arteriosclerosis. Our recent basic and clinical studies reported that nerve growth factor receptor-positive (NGFR+) MNCs suppress arterial remodeling through apoptosis, involving anti-inflammatory M2 macrophages that secrete interleukin 10, leading to reduced inflammation (AJP-Cell Physiology, 2025). However, the phenotypic characteristics of the anti-arteriosclerotic NGFR+ MNCs remain poorly understood. Purpose To investigate the traits of the anti-arteriosclerotic subset of NGFR+ MNCs. Methods Human peripheral blood mononuclear cells (MNCs) from healthy volunteers (N = 3) were collected and sorted into NGFR+ and NGFR–cell populations using fluorescence-activated cell sorting. RNA sequencing and flow cytometric analyses were performed to examine the characteristics of NGFR+ MNCs. The omics data were analyzed using MetaCore, a web-based bioinformatics tool. Global gene expression and cell surface markers were compared with published data from the analysis of MNCs via single-cell RNA sequencing (scRNA-seq) (Science, 2017). Results Gene ontology pathway analysis indicated that NGFR+ MNCs expressed genes similar to those of DCs. NGFR+ MNCs exhibited low expression of CD45 and high expression of HLA-DR but did not express CD3, CD19, CD56, or CD14, suggesting that NGFR+ MNCs were indeed DCs. NGFR+ MNCs demonstrated slight expression of the classical conventional DC (cDC) marker CD11c and the plasmacytoid DC (pDC) marker CD123. Among the six previously identified subsets of DCs in peripheral blood MNCs determined by scRNA-seq analysis, NGFR+ MNCs expressed markers from five DC subsets. NGFR+ MNCs predominantly expressed pDC subset markers (SIGLEC6, 29-fold; AXL, 55-fold; CLEC4C, 21-fold; TCF4, 9-fold, compared to MNCs) and weakly expressed cDC markers (CLEC9A, 4.7-fold; THBD, 4.9-fold, compared to MNCs). Regarding interferon (IFN) expression, NGFR+ MNCs expressed Type I IFNs, including IFNA1, 4, 13, and 17, but not Type II IFN, IFNG. These findings suggest that NGFR+ MNCs represent a DC subset that was not classified in the previously determined scRNA-seq-based subsets, thereby identifying a new subset. Conclusions NGFR+ DC represents a distinct anti-arteriosclerotic subset of DCs and a potential candidate for a new therapeutic target in arteriosclerosis.
Takashima et al. (Sat,) studied this question.