Analysis of transcriptomes of rat dendritic cell subsets and newly discovered CD103- DC-like cells., Yasushi Sawanobori, Hisashi Ueta, Yusuke Kitazawa, and Nobuko Tokuda., 18 Jan. 2024, 17 Jan. 2024, 19 Jan. 2024, Oral presentation, Japan, Unlike mouse dendritic cells (DCs), rat DCs have been canonically identified with CD103 molecules. However, in an effort to classify MHCII+ cell subsets in rat thymus, we found CD103-CD172a+CD45R- cells. This subset was morphologically similar to conventional DC subsets and commonly existed in peripheral lymphoid tissues, so we named this CD103- DC-like cells provisionally.
To characterize CD103- DC-like cells, we performed microarray analyses on conventional DC1s (cDC1s), conventional DC2s (cDC2s), and CD103- DC-like cells isolated from spleens and thymi. Although principal component analysis of the data revealed that CD103- DC-like cells are similar to cDC2s rather than cDC1, CD103- DC-like cells uniquely expressed Fcnb, Cd14, Il1a, Fn1, etc. Regarding differences between organs, thymic CD103- DC-like cells expressed uniquely Mmp14, C3, Apoc1, etc, while splenic CD103- DC-like cells expressed Nos2, Slc11a1, Gda, etc.
As CD103- DC-like cells expressed some macrophage/monocyte signature molecules, including Fn1, Ly6c, Cd14, and Mafb, we also compared CD103- DC-like cells with CD163+ macrophages. CD163+ macrophages expressed a broader spectrum of macrophage signature genes than CD103- DC-like cells, including Adgre1, Fcgr3a, and Msr1. Moreover, on a chart of principal component analysis, CD103- DC-like cells and cDCs made a cluster apart from a cluster of the macrophages, suggesting that CD103- DC-like cells are similar to cDCs rather than macrophages., False, Domestic journal
Identification of rat thymic fibroblasts and their expression of tissue-restricted antigens, Yasushi Sawanobori, Hisashi Ueta, Yusuke Kitazawa, and Nobuko Tokuda, 22 Mar. 2024, 21 Mar. 2024, 23 Mar. 2024, Oral presentation, Japan, It is well known that medullary thymic epithelial cells (mTECs) present tissue-restricted antigens (TRAs) to conduct the selection process of T cells, eventually to prevent autoimmunity. However, several reports indicate that mouse thymic medullary fibroblasts (mFbs) also express TRAs (Nitta 2020, Nitta 2021). Nevertheless, fibroblast distribution and TRA expression are not elucidated in rat thymus. We performed single-cell PCR on rat thymic stromal cells to investigate them.
After identifying the mFbs and the mTECs based on Pdgfrb and Aire on in silico analysis and immunohistochemistry, we screened two groups of candidates; the top 50 genes expressed stronger in the rat mFbs than in other thymic fibroblasts (a) and 52 genes indicated in said reports (b). The Human Protein Atlas was referred to to exclude constitutively expressed genes.
Within the candidates, 22% and 17% of genes from groups a and b were identified as mFb-associated TRAs, respectively. And 6% and 12% were identified as mFb-mTEC-associated TRAs.
These results suggest significant differences in TRA expression between rats and mice and that in vivo experiments are required to overview the TRA expression in rats., False, Domestic journal