Our detailed protocol outlines the creation and use of the advanced intestine-on-chip model, which simulates human intestinal mucosa with 3D structures and various cell types, enabling in-depth analysis of immune responses and cellular functions in response to microbial colonization.
An advanced intestine-on-chip model recreating epithelial 3D organotypic villus-like and crypt-like structures has been developed. The immunocompetent model includes Human Umbilical Vein Endothelial Cells (HUVEC), Caco-2 intestinal epithelial cells, tissue-resident macrophages, and dendritic cells, which self-organize within the tissue, mirroring characteristics of the human intestinal mucosa. A unique aspect of this platform is its capacity to integrate circulating human primary immune cells, enhancing physiological relevance. The model is designed to investigate the intestinal immune system's response to bacterial and fungal colonization and infection. Due to its enlarged cavity size, the model offers diverse functional readouts such as permeation assays, cytokine release, and immune cell infiltration, and is compatible with immunofluorescence measurement of 3D structures formed by the epithelial cell layer. It hereby provides comprehensive insights into cell differentiation and function. The intestine-on-chip platform has demonstrated its potential in elucidating complex interactions between surrogates of a living microbiota and human host tissue within a microphysiological perfused biochip platform.
Organ-on-Chip (OoC) systems represent an emerging technique of 3D cell culture that is capable of bridging the gap between conventional 2D cell culture and animal models. OoC platforms typically consist of one or more compartments containing tissue-specific cells grown on a wide range of scaffolds such as membranes or hydrogels1. The models are capable of mimicking one or more defined organotypic functions. Pumps enable continuous microfluidic perfusion of cell culture medium for removal of cellular waste products, supply with nutrition and growth factors for improved cellular differentiation, and recreating essential in vivo conditions. With the integration of immune cells, OoC systems can mimic human immune response in vitro2. To date, a wide range of organs and functional units have been presented1. These systems include models of the vasculature3, lung4, liver2,5, and intestine6 that can be facilitated for drug testing5,7 and infection studies6,8.
We here present a human intestine-on-chip model integrating human epithelial cells forming an organotypic 3D topography of villus-like and crypt-like structures combined with an endothelial lining and tissue-resident macrophages. The model is cultured in a microfluidically perfused biochip in the format of a microscopic slide. Each biochip consists of two separate microfluidic cavities. Each cavity is divided by a porous polyethylene terephthalate (PET) membrane into an upper and lower chamber. The membrane itself also serves as the scaffold for the cells to grow on each side. The pores of the membrane enable cellular crosstalk and cell migration between cell layers. Each chamber can be accessed by two female luer lock-sized ports. Optionally, an additional mini-luer lock-sized port can provide access to the upper or lower chamber (Figure 1).
The OoC platform offers a number of readouts that can be obtained from a single experiment. The intestine-on-chip is tailored towards combining perfused 3D cell culture, effluent analysis, and fluorescence microscopy to assess cell marker expression, metabolization rates, immune response, microbial colonization and infection, and barrier function3,6,8. The model includes tissue-resident immune cells and direct contact of living microorganisms with the host tissue, which is a benefit compared to other published models9. Further, epithelial cells self-organize into three-dimensional structures that provide a physiologically relevant interface for the colonization with a living microbiota6.
The presented protocol details the necessary steps for generating an immunocompetent intestine-on-chip model. We described specific techniques and possible readout methods such as immunofluorescence microscopy, cytokine and metabolite analysis, flow cytometry, protein and genetic analysis, and permeability measurement.
The described model consists of primary HUVECs, monocyte-derived macrophages, and monocyte-derived dendritic cells co-cultured with a 3D layer of intestinal epithelial cells rep…
The authors have nothing to disclose.
The work was financially supported by the Collaborative Research Center PolyTarget 1278 (project number 316213987) to V.D.W. and A.S.M. A.F. and A.S.M. further acknowledge financial support by the Cluster of Excellence "Balance of the Microverse" under Germany's Excellence Strategy – EXC 2051 – Project-ID 690 390713860. We want to acknowledge Astrid Tannert and the Jena Biophotonic and Imaging Laboratory (JBIL) for providing us access to their confocal laser scanning microscope ZEISS LSM980. Figure 1C and Figure 2 were created with Biorender.com.
96-well plate black, clear bottom | Thermo Fisher | 10000631 | Consumables |
Acetic acid | Roth | 3738.4 | Chemicals |
Alexa Fluor 488 AffiniPure, donkey, anti-mouse IgG (H+L) | Jackson Immuno Research | 715-545-150 | Secondary Antibody Vascular Staining and Epithelial Staining |
Alexa Fluor 647 AffiniPure, donkey, anti-rabbit IgG (H+L) | Jackson Immuno Research | 711-605-152 | Secondary Antibody Epithelial Staining |
Alexa Fluor 647, donkey, anti-rabbit IgG (H+L) | Thermo Fisher Scientific, Invitrogen | A31573 | Secondary Antibody Vascular Staining |
Axiocam ERc5s camera | Zeiss | 426540-9901-000 | Technical equipment |
Basal Medium MV, phenol red-free | Promocell | C-22225 | Cell culture consumables |
Biochip | Dynamic 42 | BC002 | Microfluidic consumables |
BSA fraction V | Gibco | 15260-037 | Cell culture consumables |
C2BBe1 (clone of Caco-2) | ATCC | CRL-2102 | Epithelial Cell Source |
Chloroform | Sigma | C2432 | Chemicals |
CO2 Incubator | Heracell | 150i | Technical equipment |
Collagen IV from human placenta | Sigma-Aldrich | C5533 | Cell culture consumables |
Coverslips (24 x 40 mm; #1.5) | Menzel-Gläser | 15747592 | Consumables |
Cy3 AffiniPure, donkey, anti-goat IgG (H+L) | Jackson Immuno Research | 705-165-147 | Secondary Antibody Vascular Staining |
Cy3 AffiniPure, donkey, anti-rat IgG (H+L) | Jackson Immuno Research | 712-165-150 | Secondary Antibody Epithelial Staining |
DAPI (4',6-Diamidin-2-phenylindol, Dilactate) | Thermo Fisher Scientific, Invitrogen | D3571 | Vascular and Epithelial Staining |
Descosept PUR | Dr.Schuhmacher | 00-323-100 | Cell culture consumables |
DMEM high glucose | Gibco | 41965-062 | Cell culture consumables |
DMEM high glucose w/o phenol red | Gibco | 31053028 | Cell culture consumables |
DPBS (-/-) | Gibco | 14190-169 | Cell culture consumables |
DPBS (+/+) | Gibco | 14040-133 | Cell culture consumables |
EDTA solution | Invitrogen | 15575-038 | Cell culture consumables |
Endothelial Cell Growth Medium | Promocell | C-22020 | Cell culture consumables |
Endothelial Cell Growth Medium supplement mix | Promocell | C-39225 | Cell culture consumables |
Ethanol 96%, undenatured | Nordbrand-Nordhausen | 410 | Chemicals |
Fetal bovine Serum | invitrogen | 10270106 | Cell culture consumables |
Fluorescein isothiocyanate (FITC)-dextran (3-5 kDa) | Sigma Aldrich | FD4-100MG | Chemicals |
Fluorescent Mounting Medium | Dako | S3023 | Chemicals |
Gentamycin (10mg/mL) | Sigma Aldrich | G1272 | Cell culture consumables |
GlutaMAX Supplement (100x) | Gibco | 35050061 | Cell culture consumables |
Histopaque | Sigma-Aldrich | 10771 | Cell culture consumables |
Hoechst (bisBenzimid) H33342 | Sigma-Aldrich | 14533 | Epithelial Staining |
Holotransferrin (5mg/mL) Transferrin, Holo, Human Plasma | Millipore | 616397 | Cell culture consumables |
Human recombinant GM-CSF | Peprotech | 300-30 | Cell culture consumables |
Human recombinant M-CSF | Peprotech | 300-25 | Cell culture consumables |
Illumination device | Zeiss | HXP 120 C | Fluorescence Microscope Setup |
Laser Scanning Microscope | Zeiss | CLSM980 | Fluorescence Microscope Setup |
Lidocain hydrochloride | Sigma-Aldrich | L5647 | Cell culture consumables |
Lipopolysaccharide (LPS) | Sigma | L2630 | Cell culture consumables |
Loftex Wipes | Loftex | 1250115 | Consumables |
Low attachment tubes (PS, 5 mL) | Falcon | 352052 | Consumables |
Luer adapter for the top cap (M) | Mo Bi Tec | M3003 | Microfluidic consumables |
Male mini luer plugs, row of four,PP, opaque | Microfluidic chipshop | 09-0556-0336-09 | Microfluidic consumables |
MEM Non-Essential Amino Acids Solution | Gibco | 11140 | Cell culture consumables |
Methanol | Roth | 8388.2 | Chemicals |
Microscope | Zeiss | Axio Observer 5 | Fluorescence Microscope Setup |
Microscope slides | Menzel | MZ-0002 | Consumables |
Monoclonal, mouse, anti-human CD68 Antibody (KP1) | Thermo Fisher Scientific, Invitrogen | 14-0688-82 | Primary Antibody Vascular Staining |
Monoclonal, rat, anti-human E-Cadherin antibody (DECMA-1) | Sigma-Aldrich, Millipore | MABT26 | Primary Antibody Epithelial Staining |
Multiskan Go plate reader | Thermo Fisher | 51119300 | Technical equipment |
Normal donkey serum | Biozol | LIN-END9010-10 | Chemicals |
Optical Sectioning | Zeiss | ApoTome | Fluorescence Microscope Setup |
Penicillin-Streptomycin (10,000 U/mL) | Gibco | 15140-122 | Cell culture consumables |
Plugs | Cole Parmer | GZ-45555-56 | Microfluidic consumables |
Polyclonal, goat, anti-human VE-Cadherin Antibody | R&D Systems | AF938 | Primary Antibody Vascular Staining |
Polyclonal, rabbit, anti-human Von Willebrand Factor Antibody | Dako | A0082 | Primary Antibody Vascular Staining |
Polyclonal, rabbit, anti-human ZO-1 antibody | Thermo Fisher Scientific, Invitrogen | 61-7300 | Primary Antibody Epithelial Staining |
Power Supply Microscope | Zeiss | Eplax Vp232 | Fluorescence Microscope Setup |
Primovert microscope | Zeiss | 415510-1101-000 | Technical equipment |
Reglo ICC peristaltic pump | Ismatec | ISM4412 | Technical equipment |
SAHA (Vorinostat) | Sigma Aldrich | SML0061-25MG | Chemicals |
Saponin | Fluka | 47036 | Chemicals |
S-Monovette, 7.5 mL Z-Gel | Sarstedt | 01.1602 | Consumables |
S-Monovette, 9.0 mL K3E | Sarstedt | 02.1066.001 | Consumables |
Sodium Pyruvate | Gibco | 11360-088 | Cell culture consumables |
Tank 4.5 mL | ChipShop | 10000079 | Microfluidic consumables |
Trypane blue stain 0.4% | Invitrogen | T10282 | Cell culture consumables |
Trypsin | Gibco | 11538876 | Cell culture consumables |
Tubing | Dynamic 42 | ST001 | Microfluidic consumables |
Tweezers (Präzisionspinzette DUMONT abgewinkelt Inox08, 5/45, 0,06 mm) | Roth | K343.1 | Consumables |
Wheat Germ Agglutinin (WGA) | Thermo Fisher Scientific, Invitrogen | W32464 | Epithelial Staining |
X-VIVO 15 | Lonza | BE02-060F | Cell culture consumables, Hematopoietic cell medium |
Zellkultur Multiwell Platten, 24 Well, sterile | Greiner Bio-One | 662 160 | Consumables |
Zellkultur Multiwell Platten, 6 Well, sterile | Greiner Bio-One | 657 160 | Consumables |
Zen Blue Software | Zeiss | Version 3.7 | Microscopy Software |