Amaxa 4D-Nucleofector Basic Protocol for Human Stem Cells For 4D-Nucleofector X Unit Transfection in suspension

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For 4D-Nucleofector X Unit Transfection in suspension Pluripotent cells, adherent This basic protocol describes how to easily define optimal Nucleofection Conditions for different human stem cells (e.g. H1, H7, H14, HS306). We recommend to first test a set of pre-selected Nucleofector Programs together with two of our Primary Cell 4D-Nucleofector X Kits: P3 Primary Cell 4D-Nucleofector X Kit P4 Primary Cell 4D-Nucleofector X Kit For subsequent experiments simply use the kit which yields the best results. For highest convenience of the initial optimization step we recommend using the 16-well Nucleocuvette Strip format. Determined conditions are transferable to the 100 µl single Nucleocuvette. However, you may also directly perform the optimization with the 100 µl single Nucleocuvette Format. If you have questions regarding your human stem cell of interest, please contact our Scientific Support Team for further help with the optimization. Product Description Recommended Kit(s) P3 Primary Cell 4D-Nucleofector X Kit or P4 Primary Cell 4D-Nucleofector X Kit P3 Primary Cell 4D-Nucleofector X Kit P4 Primary Cell 4D-Nucleofector X Kit Cat. No. V4XP-3012 V4XP-3024 V4XP-3032 V4XP-4012 V4XP-4024 V4XP-4032 Transfection volume 100 µl 100 µl 20 µl 100 µl 100 µl 20 µl Size [reaction] 2 x 6 24 2 x 16 2 x 6 24 2 x 16 Nucleofector Solution Supplement 2 x 0.675 ml (0.492 ml + 27% 2 x 0.15 ml (0.108 ml + 27% 2.25 ml (1.968 ml + 13% 0.5 ml (0.432 ml + 13% 0.675 ml (0.525 ml + 22% 0.15 ml (0.115 ml + 22% 2 x 0.675 ml (0.492 ml + 27% 2 x 0.15 ml (0.108 ml + 27% 2.25 ml (1.968 ml + 13% 0.5 ml (0.432 ml + 13% pmaxgfp Vector (0.5 µg/µl in 10 mm Tris ph 8.0) 30 µg 30 µg 30 µg 30 µg 30 µg - pmaxgfp Vector (0.2 µg/µl in 10 mm Tris ph 8.0) - - 45 µg - - 45 µg Single Nucleocuvette (100 µl) 12 24-12 24-16-well Nucleocuvette Strips (20 µl) - - 2 - - 2 0.675 ml (0.525 ml + 22% 0.15 ml (0.115 ml + 22% Storage and stability Store Nucleofector Solution, Supplement and pmaxgfp Vector at 4 C. For long-term storage, pmaxgfp Vector is ideally stored at -20 C. The expiration date is printed on the solution box. Once the Nucleofector Supplement is added to the Nucleofector Solution, it is stable for three months at 4 C. 4D-Nucleofector Solutions could be only used with Nucleovettes (conductive polymer cuvettes), i.e. in the 4D-Nucleofector System and the 96-well Shuttle Device. They are not compatible with the Nucleofector II/2b Device.

Optimization Guidelines The initial optimization experiment is comprised of 32 reactions, using 2 Nucleocuvette Strips: 7 different Nucleofector Programs are tested in duplicate with 2 4D-Nucleofector X Solutions plus 1 control. The program and Nucleofector Solution which turned out to be the most appropriate Nucleofection Condition should be used for all subsequent transfections. Nucleocuvette Strip 1: P3 Solution 1 2 A CA-137 CA-137 B CB-150 CB-150 C CD-118 CD-118 D CE-118 CE-118 E CM-113 CM-113 F DC-100 DC-100 G DN-100 DN-100 H Negative control (no program) Negative control (no program) Nucleocuvette Strip 2: P4 Solution 1 2 A CA-137 CA-137 B CB-150 CB-150 C CD-118 CD-118 D CE-118 CE-118 E CM-113 CM-113 F DC-100 DC-100 G DN-100 DN-100 H Negative control (no program) Negative control (no program) Compatible tips for 20 µl Nucleocuvette Strips: ept.i.p.s. [US/CDN: Eppendorf North America, Cat. No. 2491.431, Rest of World: Eppendorf AG, Cat. No. 0030073.266], Matrix TallTips [Matrix Technologies Corp., Cat. No. 7281] or LTS Tips [Rainin Instruments, LLC, Cat. No. SR-L10F, SR/SS-L250S, SR/SS-L300S]. Before using other types of pipette tips, please ensure they reach the bottom of the Nucleocuvette Wells without getting stuck Supplied pmaxgfp Vector Substrate of interest, highly purified, preferably by using endotoxin-free kits; A260:A280 ratio should be at least 1.8 Cell culture plates of your choice Coated plates (for culture with feeder cells): Prepare a culture plate coated with gelatine and inactivated feeder cells (one well per sample) 24 hours before Nucleofection Coated plates (for feeder-free culture): Prepare culture plates coated with Matrigel [BD Biosciences, Cat. No. 354277] For detaching cells: Accutase solution [PAA Laboratories, Cat. No. L11-007] or 0.05 or 0.25% Trypsin/EDTA solution [Invitrogen, Cat. No. 253000-54 or 252000-56] Culture medium (for culture with feeder cells): DMEM:F-12 [Lonza, Cat. No. 12-719F] supplemented with 15-20% serum replacement [Invitrogen, Cat. No. 10828-028], 1 2% nonessential amino acids [Lonza, Cat. No. 13-114E], 1 4 mm L-glutamine [Lonza, Cat. No. 17-605C], 0.1 mm 2-Mercaptoethanol [Invitrogen, Cat. No. 21985-023] and 4 8 ng/ml fibroblast growth factor-2 [Milipore, Cat. No. GF003AF-MG] Culture medium (for feeder-free culture): mtessr 1 medium [StemCell Technologies, Cat. No. 05850] Prewarm appropriate volume of culture medium to 37 C (see table 2) Appropriate number of cells/sample (see table 2) 1. Pre Nucleofection Required Material Please make sure that the entire supplement is added to the Nucleofector Solution. The ratio of Nucleofector Solution to supplement is 4.5 : 1 (see table 1) 4D-Nucleofector System (4D-Nucleofector Core Unit and 4D-Nucleofector X Unit) Supplemented 4D-Nucleofector Solution at room temperature Supplied 100 µl single Nucleocuvette or 20 µl 16-well Nucleocuvette Strips Transfection results may vary due to different culture conditions prior and post Nucleofection. Important considerations - Single cell suspension: 1. We recommend transfecting the cells in single cell suspension. Nucleofection of clumps leads to lower transfection efficiency and less reproducibility (for details see reference 1) 2. If single cell suspension passage is not established, please do some pre-experiments by testing Accutase (reference 2 and 3) and Trypsin (reference 4) for detachment. Cultivate the cells afterwards and analyze which method led to highest viability and lowest differentiation 2

3. The use of apoptosis inhibitors like ROCK inhibitor (reference 5) and neurotrophins (reference 6) have been reported to increase viability of hes cells. Depending on hesc culture conditions it might be advantageous to use ROCK inhibitor or neurotrophins to obtain higher viabilities Cell culture recommendations 1.1 Replace media every day 1.2 Cells should be passaged 1 2 times per week with a sub-cultivation ratio of 1 : 3 to 1 : 10. You may use collagenase, dispase or another enzyme for this purpose Detachment of stem cells A. Harvest of stem cells cultured on feeder cells There are three possibilities to remove feeder cells from your stem cell culture prior to Nucleofection : If your stem cells are usually cultured on feeder cells, passage them once to Matrigel coated plates to remove the feeder cells (described in reference 2). Then proceed to step 1.3 B Cultivate the cells on feeder cells until the day of the experiment. Detach the stem cells with Collagenase. Dissociate the clumps with Accutase into a single cell suspension Cultivate the cells on feeder cells until the day of the experiment. Detach all cells with Accutase. Incubate the cells on an uncoated cell culture flask for 1 hour in a humidified 37 C/5% CO 2 incubator. The feeder cells will attach and the stem cells will stay in suspension. Harvest the cells in suspension B. Harvest of feeder-free stem cell cultures Prior to Nucleofection detach the hes cells from the Matrigel plates by incubation with Accutase for 5 minutes at 37 C. Dissociate the cells into a single cell suspension by pipetting the suspension carefully up and down 4 6 times. Add medium to stop Accutase 2. Nucleofection For Nucleofection Sample contents and recommended Nucleofector Program, please refer to Table 3. Human stem cells are quite sensitive to environmental conditions. Therefore please ensure you proceed with the Nucleofection steps as fast as possible. 2.3 Select/Check for the appropriate Nucleofector Program (see table 3) 2.4 Prepare cell culture plates by filling appropriate number of wells with desired volume of recommended culture media (see table 4) coated with BD Matrigel or gelatine and feeder cells and preincubate/equilibrate plates in a humidified 37 C/5% CO 2 incubator 2.5 Pre-warm an aliquot of culture medium to 37 C (see table 4) 2.6 Prepare plasmid DNA or pmaxgfp Vector or sirna (see table 3) 2.7 Harvest the cells (please see 1.3) 2.8 Count an aliquot of the cells and determine cell density 2.9 Centrifuge the required number of cells (see table 3) at 115xg for 3 minutes at room temperature. Remove supernatant completely 2.10 Resuspend the cell pellet carefully in room temperature 4D- Nucleofector Solution (see table 3) 2.11 Prepare mastermixes by dividing cell suspension according to number of substrates 2.12 Add required amount of substrates to each aliquot (max. 10% of final sample volume) 2.13 Transfer mastermixes into the Nucleocuvette Vessels As leaving cells in Nucleofector Solution for extended periods of time may lead to reduced transfection efficiency and viability it is important to work as quickly as possible. Avoid air bubbles while pipetting. 2.14 Gently tap the Nucleocuvette Vessels to make sure the sample covers the bottom of the cuvette 2.15 Place Nucleocuvette Vessel with closed lid into the retainer of the 4D-Nucleofector X Unit. Check for proper orientation of the Nucleocuvette Vessel 2.16 Start Nucleofection Process by pressing the Start on the display of the 4D-Nucleofector Core Unit (for details, please refer to the device manual) 2.17 After run completion, carefully remove the Nucleocuvette Vessel from the retainer 2.18 Resuspend cells with pre-warmed medium (for recommended volumes see table 5). Mix cells by gently pipetting up and down two to three times. When working with the 100 µl Nucleocuvette use the supplied pipettes and avoid repeated aspiration of the sample 2.19 Plate desired amount of cells in culture system of your choice (for recommended volumes see table 5) 2.20 If post Nucleofection Cell Culture is done in BD Matrigel (BD Biosciences) coated plates, centrifuge the culture plates loaded with cells at this point to guarantee proper attachment of the cells (70xg, 3 minutes, room temperature) 2.1 Please make sure that the entire supplement is added to the Nucleofector Solution 2.2 Start 4D-Nucleofector System and create or upload experimental parameter file (for details see device manual) 3

s 1. The Matrigel plates used for culturing of human stem cells should be fresh. Storage of these plates for more than 7 days leads to reduced attachment of the cells post Nucleofection. 2. The plating density post Nucleofection is a critical aspect for the viability of human stem cells. Our experience is that higher densities lead to better viability of the cells. Therefore we recommend plating human stem cells at densities from 4 x 10 5 to 6.5 x 10 5 cells per cm 2. 3. The indicated plating cell numbers and volumes produce optimal Nucleofection Results in most cases. However, you may wish to test an extended range of cell numbers depending on your specific needs. 3. Post Nucleofection 3.1 Incubate the cells in a humidified 37 C/5% CO 2 incubator until analysis. Gene expression is often detectable after only 4 8 hours. To validate optimal conditions for down regulation we recommend performing a time course experiment (please see 2.6) 3.2 As cells were plated at high density post Nucleofection, a passage step 48 hours post Nucleofection using collagenase or dispase might be necessary Additional Information For an up-to-date list of all Nucleofector References, please refer to: www.lonza.com/nucleofection-citations For more technical assistance, contact our Scientific Support Team: USA /Canada Phone: 800 521 0390 (toll-free) Fax: 301 845 8338 E-mail: scientific.support@lonza.com Europe and Rest of World Phone: +49 221 99199 400 Fax: +49 221 99199 499 E-mail: scientific.support.eu@lonza.com References 1. Nucleofection Mediates High-efficiency Stable gene Knockdown and Transgene Expression in Human Embryonic Stem Cells; Kristi A. Hohenstein et al. (2008); Stem Cells First published online March 20, 2008; doi:10.1634/stemcells.2007-0857 2. Nucleofection of Human Embryonic Stem Cells; Henrike Siemen et al. (2005); Stem Cells and Development:14: 378-383 3. Efficient propagation of single cells accutase-dissociated human embryonic stem cells; Ruchi Bajpai et al. (2008); Molecular Reproduction and Development 4. Facilitated expansion of human embryonic stem cells by single cell enzymatic dissociation; Catharina Ellerström et al. (2007); Stem Cells 25:1690-1696 5. A ROCK inhibitor permits survival of dissociated human embryonic stem cells; Kiichi Watanabe etal. (2007); Nature Biotechnology 25 (6): 681-686 6. Neutrophins mediate human embryonic stem cell survival; April D. Pyle et al. (2006); Nature Biotechnology: 24 (3): 344-350 7. Efficient and Stable Transgene Expression in Human Embryonic Stem Cells Using Transposon-Mediated Gene Transfer; Andrew Wilber et al. (2007); Stem Cell 25: 2919-2927 8. Efficient Transfection of Embryonic and adult stem cells; Uma Lakshmipathy et al. (2004); Stem Cells: 22:531-543 Lonza Cologne AG 50829 Cologne, Germany Please note that the Amaxa Nucleofector Technology is not intended to be used for diagnostic purposes or for testing or treatment in humans. Amaxa Nucleofector Technology and the information contained in this protocol and all other information provided by Lonza, its affiliates or its distributors ( Information ) may only be used in compliance with all applicable laws and regulations especially but not limited to those relating to embryonic stem cell research. Lonza expressly disclaims any use of the Information for research using embryonic stem cells, independent of the place of use and the nationality of the researcher, which is contrary to any applicable law and regulation especially but not limited to those relating to embryonic stem cell research. The Nucleofector Technology, comprising Nucleofection Process, Nucleofector Device, Nucleofector Solutions, Nucleofector 96-well Shuttle System and 96-well Nucleocuvette plates and modules is covered by patent and/or patent-pending rights owned by Lonza Cologne AG. Amaxa, Nucleofector, Nucleofection, 4D-Nucleofector, Nucleocuvette and maxgfp are registered trademarks of the Lonza Cologne AG in Germany and/or U.S. and/or other countries. Other product and company names mentioned herein are the trademarks of their respective owners. This kit contains a proprietary nucleic acid coding for a proprietary copepod fluorescent protein intended to be used as a positive control with this Lonza product only. Any use of the proprietary nucleic acid or protein other than as a positive control with this Lonza product is strictly prohibited. USE IN ANY OTHER APPLICATION REQUIRES A LICENSE FROM EVROGEN. To obtain such a license, please contact Evrogen at license@evrogen.com. The CMV promoter is covered under U.S. Patents 5,168,062 and 5,385,839 and its use is permitted for research purposes only. Any other use of the CMV promoter requires a license from the University of Iowa Research Foundation, 214 Technology Innovation Center, Iowa City, IA 52242. The use of this product in conjunction with materials or methods of third parties may require a license by a third party. User shall be fully responsible for determining whether and from which third party it requires such license and for the obtainment of such license. No statement is intended or should be construed as a recommendation to infringe any existing patent. Copyright 2010, Lonza Cologne AG. All rights reserved. D4XP-9011_2010-08 4

Table 1: Volumes required for a single reaction Volume of Nucleofector Solution 82 µl 16.4 µl Volume of Supplement 18 µl 3.6 µl Table 2: Required amounts of cells and media for Nucleofection Culture medium per sample post Nucleofection (for transfer and culture) Cell number per Nucleofection Sample 1 ml 200 µl 8 x 10 5 (Lower or higher cell numbers may influence transfection results) 2 x 10 5 4 x 10 5 (Lower or higher cell numbers may influence transfection results) Table 3: Contents of one Nucleofection Sample and recommended program Cells 8 x 10 5 2 x 10 5 Substrate* pmaxgfp Vector 2 µg 0.4 µg 0.8 µg or plasmid DNA (in H 2 O or TE) 1 5 µg 0.4 1 µg or sirna 30 300nM sirna (3 30 pmol/sample) P3 or P4 4D-Nucleofector X Solution 100 µl 20 µl Program * Volume of substrate should comprise maximum 10% of total reaction volume CA-137 or CB-150 or CD-118 or CE-118 or CM-113 or DC-100 or DN-100 30 300nM sirna (0.6 6 pmol/sample) CA-137 or CB-150 or CD-118 or CE-118 or CM-113 or DC-100 or DN-100 Table 4: Culture volumes required for post Nucleofection Steps * 24-well culture plate 500 µl - 96-well culture plate - 120 µl Culture medium to be added to the sample post Nucleofection * Maximum cuvette volume 200 µl 500 µl 80 µl Table 5: Recommended volumes for sample transfer into culture plate Culture medium to be added to the sample post Nucleofection * 500 µl 80 µl Volume of sample transferred to culture plate complete sample (use supplied pipettes) 80 µl * Maximum cuvette volume 200 µl 5