M. tuberculosis infection of human iPSC-derived macrophages reveals complex membrane dynamics during xenophagy evasion.
J Cell Sci
; 134(5)2020 11 25.
Article
em En
| MEDLINE
| ID: mdl-32938685
ABSTRACT
Xenophagy is an important cellular defence mechanism against cytosol-invading pathogens, such as Mycobacterium tuberculosis (Mtb). Activation of xenophagy in macrophages targets Mtb to autophagosomes; however, how Mtb is targeted to autophagosomes in human macrophages at a high spatial and temporal resolution is unknown. Here, we use human induced pluripotent stem cell-derived macrophages (iPSDMs) to study the human macrophage response to Mtb infection and the role of the ESX-1 type VII secretion system. Using RNA-seq, we identify ESX-1-dependent transcriptional responses in iPSDMs after infection with Mtb. This analysis revealed differential inflammatory responses and dysregulated pathways such as eukaryotic initiation factor 2 (eIF2) signalling and protein ubiquitylation. Moreover, live-cell imaging revealed that Mtb infection in human macrophages induces dynamic ESX-1-dependent, LC3B-positive tubulovesicular autophagosomes (LC3-TVS). Through a correlative live-cell and focused ion beam scanning electron microscopy (FIB SEM) approach, we show that upon phagosomal rupture, Mtb induces the formation of LC3-TVS, from which the bacterium is able to escape to reside in the cytosol. Thus, iPSDMs represent a valuable model for studying spatiotemporal dynamics of human macrophage-Mtb interactions, and Mtb is able to evade capture by autophagic compartments.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tuberculose
/
Células-Tronco Pluripotentes Induzidas
/
Mycobacterium tuberculosis
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Cell Sci
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Reino Unido