A Technique to Develop a Parasite Infection in Intestinal Organoids via Microinjection
Published: October 31, 2023
Abstract
Source: Dutta, D., et al. Studying Cryptosporidium Infection in 3D Tissue-derived Human Organoid Culture Systems by Microinjection. J. Vis. Exp. (2019).
This video demonstrates a microinjection technique to develop a human intestinal organoid infection model. The infectious sporozoite stage of the parasite Cryptosporidium parvum is microinjected into the organoid lumen. Upon invading the epithelial cells of the organoid, it undergoes asexual and sexual reproduction to complete its life cycle and spreads the infection.
Protocol
1. In Vitro Purification of Sporozoites from C. parvum Oocysts Purify sporozoites from C. parvum oocysts after bleaching and washing out the bleach as described above. Transfer the oocysts to a 15 mL tube. Resuspend oocysts in room temperature excystation medium (0.75% w/v sodium taurocholate in DMEM) to obtain 1 x 107 oocysts/mL. The addition of taurocholate improves the excystation rate of the oocysts, improving sporozoite yield.</li…
Representative Results
Figure 1: Preparation and purification of Cryptosporidium oocysts and sporozoites. (A) Schematic representation of the method used for oocyst and sporozoite preparation for infection. (B) Image showing in vitro excystation of oocysts. Filtration of unexcysted oocysts and shells gives a purified solution of sporozoites. Scale bar = 10 µm.
Disclosures
The authors have nothing to disclose.
Materials
| Basement membrane extract (extracellular matrix) | amsbio | 3533-010-02 | |
| Dynamag 15 rack | Thermofisher Scientific | 12301D | |
| Dynamag 2 rack | Thermofisher Scientific | 12321D | |
| EMD Millipore Isopore Polycarbonate Membrane Filters- 3µm | EMD-Millipore | TSTP02500 | |
| Fast green dye | SIGMA | F7252-5G | |
| Femtojet 4i Microinjector | Eppendorf | 5252000013 | |
| Glass capillaries of 1 mm diameter | WPI | TW100F-4 | |
| Matrigel (extracellular matrix) | Corning | 356237 | |
| Microfuge tube 1.5ml | Eppendorf | T9661-1000EA | |
| Micro-loader tips | Eppendorf | 612-7933 | |
| Micropipette puller P-97 | Shutter instrument | P-97 | |
| Penstrep | Gibco | 15140-122 | |
| Sodium hypoclorite (use 5%) | Clorox | 50371478 | |
| Super stick slides | Waterborne, Inc | S100-3 | |
| Swinnex-25 47mm Polycarbonate filter holder | EMD-Millipore | SX0002500 | |
| Taurocholic acid sodium salt hydrate | SIGMA | T4009-5G | |
| Tween-20 | Merck | 8221840500 | |
| Vortex Genie 2 | Scientific industries, Inc | SI0236 | |
| Adv+++ (DMEM+Penstrep+Glutamax+Hepes) | Final amount | ||
| DMEM | Invitrogen | 12634-010 | 500ml |
| Penstrep | Gibco | 15140-122 | 5ml of stock in 500ml DMEM |
| Glutamax | Gibco | 35050038 | 5ml of stock in 500ml DMEM |
| Hepes | Gibco | 15630056 | 5ml of stock in 500ml DMEM |
| INTESTINAL ORGANOID MEDIA-OME (Expansion media) | Final concentration | ||
| A83-01 | Tocris | 2939-50mg | 0.5µM |
| Adv+++ | make upto 100 ml | ||
| B27 | Invitrogen | 17504044 | 1X |
| EGF | Peprotech | AF-100-15 | 50ng/mL |
| Gastrin | Tocris | 3006-1mg | 10 nM |
| NAC | Sigma | A9125-25G | 1.25mM |
| NIC | Sigma | N0636-100G | 10mM |
| Noggin CM | In house* | 10% | |
| P38 inhibitor (SB202190) | Sigma | S7076-25 mg | 10µM |
| PGE2 | Tocris | 2296-10 | 10 nM |
| Primocin | InvivoGen | ant-pm-1 | 1ml/500ml media |
| RSpoI CM | In house* | 20% | |
| Wnt3a CM | In house* | 50% | |
| In house* – cell lines will be provided upon request | |||
| INTESTINAL ORGANOID MEDIA-OMD (Differentiation media) | To differentiate organoids, expanding small intestinal organoids were grown in a Wnt-rich medium for six to seven days after splitting, and then grown in a differentiation medium (withdrawal of Wnt, nicotinamide, SB202190, in a differentiation medium (withdrawal of Wnt, nicotinamide, SB202190, prostaglandin E2 from a Wnt-rich medium or OME) | ||
| Reducing buffer (for resuspension of oocysts and sporozoites for injection) | Final concentration | ||
| L-Glutathione reduced | Sigma | G4251-10MG | 0.5 μg/μl of OME/OMD/LOM |
| Betaine | Sigma | 61962 | 0.5 μg/μl of OME/OMD/LOM |
| L-Cysteine | Sigma | 168149-2.5G | 0.5 μg/μl of OME/OMD/LOM |
| Linoleic acid | Sigma | L1376-10MG | 6.8 μg/ml of OME/OMD /LOM |
| Taurine | Sigma | T0625-10MG | 0.5 μg/μl of OME/OMD/LOM |
Tags
Cite This Article
A Technique to Develop a Parasite Infection in Intestinal Organoids via Microinjection. J. Vis. Exp. (Pending Publication), e21720, doi: (2023).