Intestinal goblet cells sample and deliver lumenal antigens by regulated endocytic uptake and transcytosis
- University of Gothenburg, Sweden
- Washington University in Saint Louis School of Medicine, United States
- University of Michigan, United States
- Washington University School of Medicine, United States
- Harvard Medical School, United States
Abstract
Intestinal goblet cells maintain the protective epithelial barrier through mucus secretion and yet sample lumenal substances for immune processing through formation of goblet cell associated antigen passages (GAPs). The cellular biology of GAPs and how these divergent processes are balanced and regulated by goblet cells remains unknown. Using high resolution light and electron microscopy, we found that in mice, GAPs were formed by an acetylcholine (ACh) dependent endocytic event remarkable for delivery of fluid phase cargo retrograde into the trans golgi network and across the cell by transcytosis - in addition to the expected transport of fluid phase cargo by endosomes to multi-vesicular bodies and lysosomes. While ACh also induced goblet cells to secrete mucins, ACh-induced GAP formation and mucin secretion were functionally independent and mediated by different receptors and signaling pathways, enabling goblet cells to differentially regulate these processes to accommodate the dynamically changing demands of the mucosal environment for barrier maintenance and sampling of lumenal substances.
Data availability
All data generated and analysed for this study are included in the manuscript and source data files for figure 8
Article and author information
Author details
Funding
National Institute of Diabetes and Digestive and Kidney Diseases (DK097317)
- Rodney D Newberry
Stiftelserna Wilhelm och Martina Lundgrens
- Jenny K Gustafsson
Åke Wiberg Stiftelse
- Jenny K Gustafsson
Jeanssons Stiftelser
- Jenny K Gustafsson
National Institute of Allergy and Infectious Diseases (AI131342)
- Rodney D Newberry
National Institute of Diabetes and Digestive and Kidney Diseases (DK109006)
- Kathryn A Knoop
National Institute of Allergy and Infectious Diseases (AI136515)
- Rodney D Newberry
National Institute of Allergy and Infectious Diseases (AI140755)
- Rodney D Newberry
National Institute of Allergy and Infectious Diseases (AI112626)
- Simon P Hogan
National Institute of Diabetes and Digestive and Kidney Diseases (DK048106)
- Wayne I Lencer
Crohn's and Colitis Foundation (34835)
- Jenny K Gustafsson
Vetenskapsrådet (2014-00366)
- Jenny K Gustafsson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal procedures and protocols were performed in accordance with the Institutional Animal Care and Use Committee at Washington University School of Medicine (Animal Wellfare Assurance number: A-3381-01) and the Swedish animal welfare legislation and approved by the Swedish Laboratory Animal Ethical Committee in Gothenburg (Ethical permit ID number: 5.8.18-11053/2019.
Copyright
© 2021, Gustafsson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 5,438
- views
-
- 779
- downloads
-
- 46
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Intestinal goblet cells sample and deliver lumenal antigens by regulated endocytic uptake and transcytosis
eLife 10:e67292.
https://doi.org/10.7554/eLife.67292
Further reading
-
- Cell Biology
- Immunology and Inflammation
Arpin was discovered as an inhibitor of the Arp2/3 complex localized at the lamellipodial tip of fibroblasts, where it regulated migration steering. Recently, we showed that arpin stabilizes the epithelial barrier in an Arp2/3-dependent manner. However, the expression and functions of arpin in endothelial cells (EC) have not yet been described. Arpin mRNA and protein are expressed in EC and downregulated by pro-inflammatory cytokines. Arpin depletion in Human Umbilical Vein Endothelial Cells causes the formation of actomyosin stress fibers leading to increased permeability in an Arp2/3-independent manner. Instead, inhibitors of ROCK1 and ZIPK, kinases involved in the generation of stress fibers, normalize the loss-of-arpin effects on actin filaments and permeability. Arpin-deficient mice are viable but show a characteristic vascular phenotype in the lung including edema, microhemorrhage, and vascular congestion, increased F-actin levels, and vascular permeability. Our data show that, apart from being an Arp2/3 inhibitor, arpin is also a regulator of actomyosin contractility and endothelial barrier integrity.
-
- Cell Biology
The excessive cosolute densities in the intracellular fluid create a physicochemical condition called macromolecular crowding (MMC). Intracellular MMC entropically maintains the biochemical thermodynamic equilibria by favouring associative reactions while hindering transport processes. Rapid cell volume shrinkage during extracellular hypertonicity elevates the MMC and disrupts the equilibria, potentially ushering cell death. Consequently, cells actively counter the hypertonic stress through regulatory volume increase (RVI) and restore the MMC homeostasis. Here, we establish fluorescence anisotropy of EGFP as a reliable tool for studying cellular MMC and explore the spatiotemporal dynamics of MMC during cell volume instabilities under multiple conditions. Our studies reveal that the actin cytoskeleton enforces spatially varying MMC levels inside adhered cells. Within cell populations, MMC is uncorrelated with nuclear DNA content but anti-correlated with the cell spread area. Although different cell lines have statistically similar MMC distributions, their responses to extracellular hypertonicity vary. The intensity of the extracellular hypertonicity determines a cell's ability for RVI, which correlates with Nuclear Factor Kappa Beta (NFkB) activation. Pharmacological inhibition and knockdown experiments reveal that Tumour Necrosis Factor Receptor 1 (TNFR1) initiates the hypertonicity induced NFkB signalling and RVI. At severe hypertonicities, the elevated MMC amplifies cytoplasmic microviscosity and hinders Receptor Interacting Protein Kinase 1 (RIPK1) recruitment at the TNFR1 complex, incapacitating the TNFR1-NFkB signalling and consequently, RVI. Together, our studies unveil the involvement of TNFR1-NFkB signalling in modulating RVI and demonstrate the pivotal role of MMC in determining cellular osmoadaptability.
