Stem cell derived cultures harbor tremendous potential to model infectious diseases. Here, the culture of mouse and human gastric organoids derived from adult stem cells is described. The organoids are microinjected with the gastric pathogen Helicobacter pylori.
Recently infection biologists have employed stem cell derived cultures to answer the need for new and better models to study host-pathogen interactions. Three cellular sources have been used: Embryonic stem cells (ESC), induced pluripotent stem cells (iPSC) or adult stem cells. Here, culture of mouse and human gastric organoids derived from adult stem cells is described and used for infection with the gastric pathogen Helicobacter pylori. Human gastric glands are isolated from resection material, seeded in a basement matrix and embedded in medium containing growth factors epidermal growth factor (EGF), R-spondin, Noggin, Wnt, fibroblast growth factor (FGF) 10, gastrin and transforming growth factor (TGF) beta inhibitor. In these conditions, gastric glands grow into 3-dimensional organoids containing 4 lineages of the stomach. The organoids expand indefinitely and can be frozen and thawed similarly as cell lines. For infection studies, bacteria are microinjected into the lumen of the organoids. Infected organoids are processed for imaging. The described methods can be adapted to other organoids and infections with other bacteria, viruses or parasites. This allows the study of infection-induced changes in primary cells.
Studiet av patogener er avhengig av tilstrekkelig modellsystemer for å etterligne in vivo infeksjon. For noen smittestoffer, er tilstrekkelige modellsystemer mangler mens noen av de brukte systemene er langt fra optimal. Et eksempel er den gastriske bakterien Helicobacter pylori (H. pylori), som er kausalt relatert til utvikling av magekreft. Men i mangel av et mer passende cellekultur system, mange studier som tar sikte på å analysere de molekylære mekanismene bak kreftutvikling bruk kreftcellelinjer, som representerer endepunktet for kreft kaskade. Primære, ikke-transformerte celler ville være en bedre modell for disse studiene. Imidlertid primære celler er kun tilgjengelig fra et lite antall donorer, og kan ikke bli dyrket over lengre tidsperioder. I de senere årene har stamcelleforskning gjort betydelige fremskritt for å gi nye kilder for primære cellekulturer for studiet av infeksjon biologi.
Kulturer fratre stamcelle kilder er brukt: embryonale stamceller (ESC), induserte pluripotente stamceller (IPSC) eller voksne stamceller. De er blitt brukt til å modellere infeksjoner med virus, slik som cytomegalovirus 1,2 eller hepatitt C-virus 3 – 7, parasitter, slik som Plasmodium falciparum 8 eller 9 Toxoplasma gondii, og bakterier, for eksempel Bacterioides thetaiotaomicron 10 eller Salmonella enterica 11. Nå nylig, har flere tilnærminger er publisert for å modellere infeksjon med H. pylori med organoids avledet fra MGP eller iPS-celler 12, mus voksne stamceller 21,22 eller menneskelige voksne stamceller 13 – 15.
Utviklingen av organoid kulturer fra voksne stamceller stammer fra en studie hvor enkelt stamceller isolert fra murine tarmepitelet ble sådd ut på en tre-dimensjonal matrise oginnebygd i medium som etterlignet miljøet av tarm stamceller inneholdende EGF som mitogen, R-spondin å forbedre Wnt signalering og Noggin å inhibere benmorfogent protein (BMP) signal 16. Spesielt disse kulturene ikke krever co-kultur med mesenchymalceller. Under disse forhold vil stamcellene proliferere og danne små strukturer med domener husing celler i tarm krypter, og domener som inneholder cellene i tarmtott. De organoids således selv organisere å etterligne in vivo situasjonen. I dag kan adulte stamceller fra mange murine og humane vev dyrkes in vitro og selv organisere inn organoids som ligner deres de vivo motstykke, som tynntarm og tykktarm 17, mage 13,18, lever 19,20, bukspyttkjertel 21 og prostata 22.
Her gir vi en video protokoll til kultur mus eller menneskelige mage organoids fra voksen stilk cells og microinject dem med H. pylori. Denne protokollen er basert på tidligere rapporter 13,18. Denne fremgangsmåten kan tilpasses for dyrking og infisere andre organoid kulturer som intestinale organoids.
This protocol describes the use of ever-expanding, untransformed primary organoids from adult stem cells for infection biology. Critical steps are i) the isolation of viable glands, ii) expansion of organoids and iii) the microinjection. Below are some suggestions for modifications, troubleshooting and technical considerations.
Compared to other isolation methods, which use vigorous shaking or pipetting to release glands and can be equally successful, the technique presented here has the adva…
The authors have nothing to disclose.
This work was supported by EU Marie Curie Fellowship (EU/300686-InfO) to S.B. and a Research Prize from the United European Gastroenterology Foundation to H.C. We would like to thank Harry Begthel, Jeroen Korving and the Hubrecht Imaging Center for technical assistance, Meritxell Huch for help with initial organoid culture and Yana Zavros for discussion.
Medium | |||
HEPES | Invitrogen | 15630-056 | |
Advanced DMEM/F12 | Invitrogen | 12634-028 | |
Matrigel, GFR, phenol free | BD | 356231 | |
GlutaMAX | Invitrogen | 35050-079 | Stock concentration 200 mM, final concentration 2 mM |
B27 | Invitrogen | 17504-044 | Stock concentration 50 x, final concentration 1x |
N-Acetylcysteine | Sigma-Aldrich | A9165-5G | Stock concentration 500 mM, final concentration 1 mM |
Murine recombinant EGF | Invitrogen | PMG8043 | Stock concentration 500 µg/mL, final concentration 50 ng/mL |
Human recombinant FGF10 | Peprotech | 100-26 | Stock concentration 100 µg/mL, final concentration 200 ng/mL |
TGFβi A-83-01 | Tocris | 2939 | Stock concentration 500 µM, final concentration 2 µM |
Nicotinamide | Sigma-Aldrich | N0636 | Stock concentration 1 M, final concentration 10 mM |
[Leu15]-Gastrin | Sigma-Aldrich | G9145 | Stock concentration 100 µM, final concentration 1 nM |
RHOKi Y-27632 | Sigma-Aldrich | Y0503 | Stock concentration 10 mM, final concentration 10 µM |
Wnt3A conditioned medium | Stable cell line generated in the Clevers Lab. Final concentration 50%. Cells can be obtained from Hans Clevers. | ||
R-spondin1 conditioned medium | Stable cell line generated in the Kuo Lab. Final concentration 10%. Cell line can be obtained from Calvin Kuo, Stanford. | ||
Noggin conditioned medium | Stable cell line generated in the Clevers Lab. Final concentration 10%. Cells can be obtained from Hans Clevers. | ||
R-spondin3 | R&D | 3500-RS/CF | Alternative source for R-spondin. This has been tested on human intestine organoids (1 µg/mL), but not yet on gastric organoids. |
Noggin | Peprotech | 120-10 | Alternative source for noggin. This has been tested on human intestine organoids (100 ng/mL), but not yet on gastric organoids. |
TrypLE express | Life Technologies | 12605036 | Enzymatic dissociation solution |
CoolCell® Alcohol-Free Cell Freezing Containers | biocision | BCS-405 | |
Recovery Cell Culture Freezing Medium | Invitrogen | 12648-010 | |
Antibiotics | |||
Primocin | Invivogen | ant-pm-1 | An antibiotics composition agains bacteria and fungi. It is helpful after initiation of a culture. For long term culture you can switch to other antibiotics or none. |
Penicillin/Streptomycin | Invitrogen | 15140-122 | Stock concentration 10000/10000 U/mL, final concentration 100/100 U/mL. Can be used alternatively to Primocin in long term culture. |
Otro | |||
Tweezers | Neolabs | 2-1033 | Tweezers with fine tips are helpful for the removal of muscle layer from the tissue. |
4 Well Multidishes | Thermo Scientific | 144444 | You can use other Multidishes. These were particularly helpful for microinjections because they have a low outer rim and allow more mobility for the manipulator. |
Micromanipulator | Narishige | M-152 | |
Microinjector | Narishige | IM-5B | |
Stereomicroscope | Leica | MZ75 | |
Workbench | Clean Air | Custom made to fit the stereomicroscope in ML2 condition | |
Cappillaries | Harvard Apparatus | GC100T-10 | 1 mm outer diameter, 0,78 mm inner diameter. |
Micropipette Puller | Sutter Instruments | Flaming Brown Micropipette Puller | |
anti Cag A antibody | Santa Cruz | sc-25766 |