Biology subjects

Ivarsson, M. A.

Publications and source records attributed to Ivarsson, M. A..

2 recordsLinked to original sources

bioRxiv2024

Distinct tissue-dependent composition and gene expression of human fetal innate lymphoid cells

The human fetal immune system starts to develop in the first trimester and likely plays a crucial role in fetal development and maternal-fetal tolerance. Innate lymphoid cells (ILCs) are the earliest lymphoid cells to arise in the human fetus. ILCs consists of natural killer (NK) cells, ILC1s, ILC2s, and ILC3s that all share a common lymphoid origin. Here, we studied fetal ILC subsets, mainly NK cells and ILC3s and their potential progenitors, across human fetal tissues from the first and second trimesters. Our results show that fetal ILC subsets have distinct distribution, developmental kinetics, and gene expression profiles across human fetal tissues. Furthermore, we identify a putative CD34+ROR{gamma}t+Eomes+/- ILC progenitor population exclusively present in fetal intestine, indicating that tissue-restricted development of ILCs could contribute to the variation in ILC composition and gene expression between tissues.

immunology↗

bioRxiv2020

The identity of human tissue-emigrant CD8+ T cells

Lymphocyte migration is essential for human adaptive immune surveillance. However, our current understanding of this process is rudimentary, because most human studies to date have been restricted to immunological analyses of blood and various tissues. To address this issue, we used an integrated approach to characterize tissue-emigrant immune cells in thoracic duct lymph (TDL). In humans and non-human primates, lymphocytes were by far the most abundant immune lineage population in efferent lymph, and a vast majority of these lymphocytes were T cells. Cytolytic CD8+ T cell subsets were clonotypically discrete and selectively confined to the intravascular circulation, persisting for months after inhibition of S1P-dependent tissue egress by FTY-720. In contrast, non-cytolytic CD8+ T cell subsets with stem-like epigenetic and transcriptional signatures predominated in tissues and TDL. Collectively, these data provide an atlas of the migratory immune system and define the nature of tissue-emigrant CD8+ T cells that recirculate via TDL.

immunology↗