A two-step human culture system replicates intestinal monocyte maturation cascade: conversion of tissue-like inflammatory monocytes into macrophages

ABSTRACT: Monocyte maturation program into macrophages (MΦ) is well-defined in murine gut under homeostatic or inflammatory conditions. Obviously, in vivo tracking of monocytes in inflamed tissues remains difficult in humans. Furthermore, in vitro models fall short in generating the surrogates of transient extravasated tissue inflammatory monocytes. Here, we aimed to unravel environmental cues that replicate in vitro the human monocyte “waterfall” process by first generating tissue-like inflammatory monocytes, and then shifted them towards MΦ. Purified CD14+CD16- monocytes cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF), IFNg and IL23 differentiated into CD14+CD163- cells displayed a monocyte-like morphology. The in vitro generated inflammatory CD14+CD163- cells (Infl mo-like), like the CD14+CD163- mo-like cells that accumulate in inflamed colon of Crohn’s disease patients, promoted IL-1β-dependent memory Th17 and Th17/Th1 responses. Next, in vitro generated Infl mo-like cells converted to functional CD163+ MΦ following exposure to TGFβ and IL10. Gene set enrichment analysis further revealed a shared molecular signature between converted CD163+ MΦ and MΦ detected in various inflamed non-lymphoid and lymphoid diseased tissues. Our findings propose a two-step in vitro culture that recapitulates human monocyte maturation cascade in inflamed tissue. Manipulating this process might open therapeutic avenues for chronic inflammatory disorders. Classical CD14+CD16- human monocytes were sorted and cultured for 6 days with GM-CSF+IFNg+IL23, leading to the generation of CD163- d6 cells. Following the 6 days culture with GM-CSF+IFNg+IL23, TGFβ+IL10 were added for another 6 days. This gave rise to the CD163+ d12 and CD163- d12 populations. We used microarray (Clariom D, Affymetrix) to observe molecular differences in the 3 in vitro generated populations: (1) CD163- d6 (2) CD163+ d12 (3) CD163- d12.

ORGANISM(S): Homo sapiens

PROVIDER: GSE149722 | GEO | 2020/06/23

REPOSITORIES: GEO