# Commercially available synthetic hydrogels cannot replace Matrigel in promoting polarization and lumenogenesis of 3D ESC aggregates Authors

Vincent Brochard, Alice Galle, Alice Jouneau

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Vincent Brochard, Alice Galle, Alice Jouneau. Commercially available synthetic hydrogels cannot replace Matrigel in promoting polarization and lumenogenesis of 3D ESC aggregates Authors. 2026, 10.60675/yrr0-6e39/sn20260212-12r/short-notes. hal-05510050

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Submitted on 13 Feb 2026

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# Commercially available synthetic hydrogels cannot replace Matrigel in promoting polarization and lumenogenesis of 3D ESC aggregates

## Authors

Vincent Brochard ¹, Alice Galle ¹,² and Alice Jouneau ¹,*

## Affiliations

1 Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France

2 Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France. (Present address: Institut Pasteur, INSERM U1222, Paris, France)

* Corresponding Author: alicejouneau@inrae.fr

## Abstract

Pluripotency is defined as the ability of cells to differentiate into all cell types. *In vivo*, this capacity is gradually acquired by pluripotent cells in the epiblast as they polarize and arrange themselves into a three-dimensional structure known as a 'rosette', which then forms a lumen. Major epigenetic and metabolic changes occur during this crucial period of early development. Embryonic stem cells (ESCs), an *in vitro* model for early epiblast cells, can self-organise into rosettes when cultured in 3D, making them an ideal model for studying the events that accompany this morphogenesis. While this model is relevant to the 3Rs in terms of reducing the use of embryos, there is a significant drawback: the hydrogel commonly used for 3D cultures, Matrigel, is derived from animals. Furthermore, some rosette formation protocols use a serum-containing medium. The aim of this study was therefore to test alternative, commercially available, synthetic hydrogels and to compare the use of serum-containing and serum-free medium for modelling epiblast morphogenesis. Our results demonstrate that morphogenesis is more efficient in serum-free medium but did not occur in the synthetic hydrogels tested. This underscores the need for further optimisation of these systems.

**Keywords:** polarization – lumenogenesis – basement membrane

<figure><img src="image_2.png" /></figure>
## Introduction

Pluripotency is characterized by the capacity of cells to differentiate into all somatic lineages. *In vivo*, pluripotent epiblast cells progressively acquire this ability as they polarize and self-organize into a three-dimensional structure known as a “rosette,” which subsequently hollows out to form the pro-amniotic cavity (1). This tightly regulated morphogenetic process occurs during early post-implantation stages in both mouse and human embryos (2). Importantly, these events can be recapitulated *in vitro* using pluripotent embryonic stem cells (ESCs), providing a powerful model system to dissect the cellular and molecular mechanisms underlying polarization and lumen formation (1,2).

In this *in vitro* model, individual ESCs embedded within a complex basement membrane-rich hydrogel proliferate and assemble into polarized aggregates, or rosettes, which ultimately develop a central lumen. This three-dimensional culture system has already yielded significant insights, including the identification of key roles for WNT signalling pathways in lumenogenesis (3–5).

Although this model is relevant to the 3Rs in terms of reduction of the use of embryos, it still has a major drawback, as the hydrogel widely used for 3D cultures, known as Matrigel, is extracted from Engelbreth-Holm-Swarm mouse sarcomas (6,7). Matrigel is a heterogeneous matrix composed of extracellular matrix glycoproteins present in the basement membrane (such as laminin, collagen, entactin, and perlecan) and growth factors, even in its “growth factor-reduced” form (6). Furthermore, many protocols for ESC-based 3D morphogenesis still employ foetal calf serum in culture media (1,2).

To address these limitations and reduce dependence on animal-derived products, we sought to identify suitable alternatives to both serum and Matrigel. Although synthetic hydrogels have been developed for various applications, their fabrication requires expertise in complex chemistry and quality-control of multiple physical parameters (6,8). Recently, a few commercially available, ready-to-use hydrogels have become available. Here, we established a detailed phenotypic benchmark of rosette development in Matrigel, assessing the kinetics and efficiency of polarization and lumenogenesis in both serum-containing and serum-free conditions. Immunofluorescence analyses at multiple time points, using markers of polarization and lumen formation, provided a reference framework for comparing aggregate formation and structure in alternative hydrogel matrices. Our results demonstrate that morphogenesis is more efficient in serum-free medium, but fails to occur in the synthetic hydrogels tested, underscoring the need for further optimization of these systems.

## Results

### Characteristics of cyst formation in Matrigel

Murine ESCs were used to follow the formation of cysts upon embedding into a 3D matrix. Cell suspensions were mixed with cold Matrigel at a defined density in either a serum-containing medium (DMEM + 15% FCS) or a serum-free medium (N2B27). Following incubation at 37°C, Matrigel/cell domes had solidified and were then covered with one of the two media (see Material and Methods for details). Cells divided and rapidly organized into a rosette-like structure (Figure 1A, 24 and 48h). We used both cortical Actin and Podocalyxin-like (PODXL) staining to highlight polarization. PODXL is a
membrane-bound, negatively charged protein that accumulates at the apical side of the cells (1). The colocalization of both proteins at the centre of the rosette was used as a criterion for polarization. Lumen formation was visible when apical membranes were visually separated (Figure 1A). This occurred as early as 48h and as late as 72h. Examples of polarized rosettes with or without lumen are shown in Figure 1B. During this morphogenesis, pluripotency was maintained, as demonstrated by the expression of OCT4, although it tended to be down-regulated at 72h (Figure 1C).

We then assessed the efficiency of polarization and lumenogenesis over time when aggregates were cultured in medium with or without serum (Figure 1D). The overall efficiency of polarization was similar, with about 80% of aggregates forming polarized rosettes in both media. Lumen formation was, however, much more efficient in serum-free medium. This was not due to a different pace of proliferation, as the cell number in each rosette increased similarly over time in the two media (Figure 1E). Interestingly, we also observed that a minimum number of cells (median 18 cells) in polarized aggregates was necessary to start lumenogenesis at 48h (Figure 1F). These observations suggest that only actively proliferating polarized rosettes are able to initiate lumen formation.

## Assessment of different commercially available synthetic hydrogels

We sought to replace Matrigel with commercial synthetic hydrogels for rosette formation. We selected hydrogels that were easy to handle, compatible with immunolabelling and functionalized with adhesion proteins. Three brands were tested, VitroGel (The Well Bioscience), Peptigel (Cell Guidance Systems), and TrueGel3D (Sigma-Aldrich). These hydrogels are functionalized with peptides corresponding to different extracellular matrix proteins, laminin (A4-LN) or collagen (A4-GFO) derived peptides for Peptigel, or Fibronectin derived peptide (RGD) for TrueGel3D. VitroGel provides a series of different hydrogels, functionalized with mixtures of peptides, the exact composition being proprietary.

We embedded mouse ESCs into each hydrogel, using either serum containing or serum-free medium. Matrigel was always used in parallel as a control. To vary the kind of functionalization, we mixed V1 and V4 VitroGel kits, and the two kinds of Peptigel. In addition, the stiffness of the hydrogel was also considered. *In vivo* the stiffness of the matrix around the post-implantation embryo has been evaluated as 200-400 Pa, which was in the same range as the one measured within colonies of mouse ESCs (9–11). Matrigel stiffness varies from batch to batch and has been reported to range from 400 to 800 Pa (6). According to available information, VitroGel VHM stiffness ranges from 300 to 900 Pa, Peptigel A4 from 700 to 1300 and TrueGel3D 400 Pa. Some hydrogels were also used in a diluted form to ensure they remained within the Matrigel stiffness range (see Table 1).

All tested conditions yielded similar outcomes. First, a high rate of mortality was observed as early as 24h after formation of hydrogel/cell domes (data not shown). At 48h, few aggregates remained, reflecting the high initial mortality rate (Figure 2A, arrows). Immunostaining of Actin, PODXL and DAPI was performed at 48h to evaluate the structure of the formed aggregates (Figure 2). 3D images of several domes across independent experiments showed that no aggregates had formed polarized
rosettes. At 72h, no additional progress in terms of polarization was detected. Moreover, more deaths were observed, and proliferation was minimal or absent (data not shown).

Discussion

When cultured in three-dimensional (3D) environments with basement membrane proteins, embryonic stem cells (ESCs) can recapitulate key morphogenetic processes observed in the epiblast. The first step is cellular polarization, with the apical side of cells oriented toward the centre of the rosette structure. Once a critical cell number is reached, lumenogenesis is initiated, resulting in the formation of a hollow cyst within three days. Our findings demonstrate that this process is significantly more efficient in serum-free medium compared to serum-containing conditions, thus addressing our primary objective.

In contrast, none of the commercially available hydrogels tested were able to replace Matrigel under these conditions. First, all exhibited substantial cellular toxicity, with a high proportion of cells dying within 24 hours of 3D culture. Second, surviving cells formed disorganized aggregates, showing no evidence of polarization or lumenogenesis. At this embryonic stage, the epiblast is naturally surrounded by Laminin 511 and 111, Collagen IV, Nidogen, and Perlecan (12,13). One possible explanation is that the functionalization of synthetic hydrogels with peptide mimics of extracellular matrix (ECM) proteins does not fully replicate the complex network of native proteins present in Matrigel. While these peptides target interaction sites between ECM proteins and cell adhesion molecules such as integrins, such simplified interactions may be insufficient to fully recapitulate the signalling environment required for this specific morphogenetic process.

Studies using synthetic hydrogels for 3D morphogenesis with pluripotent cells remain limited. Polarized cyst formation has been achieved with mouse ESCs or human induced pluripotent stem cells (iPSCs) when polyethylene glycol (PEG) were functionalized with native laminin or alginate with high-density RGD peptides (14,15). Notably, a recent study reported efficient lumenogenesis using hiPSCs in synthetic PEG hydrogels without any matrix adhesion cues, highlighting a discrepancy with previous findings (16). The common factor in successful studies is the use of custom-fabricated hydrogels, allowing precise control over chemistry, polymer concentration, and stiffness. Notably, all the tested hydrogels have a polysaccharide base (dextran or others) while in the published studies mentioned above, they have a polyethylene glycol base. This difference in polymer backbone may contribute to the distinct biological outcomes observed. Therefore, while epiblast-like morphogenesis was not achieved with the ready-to-use hydrogels tested here, this does not exclude the possibility of developing synthetic alternatives to Matrigel in the future.

Finally, the hydrogels evaluated in this study may still be suitable for other applications. The detailed protocols provided in the Materials and Methods section will serve as a valuable resource for researchers interested in exploring their potential uses.
## Acknowledgments

This project was realized entirely with the financial support of GIS FC3R on funds managed by INSERM (ROSETTE, 22FC3R-010). Imaging was done at MIMA2 ISC INRAE, France (doi: 10.15454/1.5572348210007727E12).

## Author contributions

VB: methodology, Investigation

AG: Investigation

AJ: Conceptualization, Formal analysis, Visualization, Writing

## References

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<figure><img src="image_3.png" /><figcaption>Figure 1</figcaption></figure>

Characterisation of aggregates of ESCs in Matrigel. A: representative images of individual 3D aggregate at 24, 48 and 72h in Matrigel, after immunolabelling of ACTIN (in red) and PODXL (green). The PODXL-ACTIN double staining appears yellow. Nuclei are stained with DAPI (grey). B: Examples of aggregates with or without lumen, stained with ACTIN and PODXL. C: immunolabeling with OCT4 (green) and ACTIN (red) to illustrate the maintenance of pluripotency during morphogenesis. D: proportion (%) of polarised aggregates with or without lumen, of ESCs cultured in serum-free of serum-containing medium. \* statistically different (χ2 test, Pvalue=3,9 10-10). E: boxplots showing the distribution of cell number in each aggregate, in the two media (serum-free and serum-containing). F: boxplots showing the distribution of cell number in aggregates with or without a lumen, in serum-free medium. The number of rosettes analysed ranges from 30 to 300, corresponding to two or three independent experiments. \* statistically different (Student's t-test, Pvalue< 2 10-9).
<figure><img src="image_4.png" /><figcaption>Figure 2</figcaption></figure>

Representative images of 3D cultures of ESC in synthetic hydrogels, at 48h, in comparison with Matrigel. Cells in serum-free medium were embedded at the same initial density (800 cells/µl) and immunostained at 48h with ACTIN (red), PODXL (green), and DAPI (grey). A: overview of a representative plane. Arrows indicate dead cells. B: details of a couple of aggregates to highlight absence of polarization in synthetic hydrogels. Scale bars 50 µm.
<table><caption>Table 1: list of assays using different synthetic hydrogels</caption><thead><tr><th rowspan="2"></th><th rowspan="2">% hydrogel<br>medium</th><th colspan="2">50%</th><th colspan="2">66%</th><th rowspan="2"></th></tr><tr><th>serum</th><th>no serum</th><th>serum</th><th>no serum</th></tr></thead><tbody><tr><td rowspan="6">VitroGel</td><td>VHMO1</td><td>x3</td><td>x4</td><td>x3</td><td>x3</td><td>n=13</td></tr><tr><td>V1</td><td></td><td>x2</td><td>x1</td><td></td><td>n=3</td></tr><tr><td>V2</td><td></td><td>x2</td><td>x1</td><td></td><td>n=3</td></tr><tr><td>V3</td><td></td><td>x2</td><td>x1</td><td></td><td>n=3</td></tr><tr><td>V4</td><td></td><td>x2</td><td>x1</td><td></td><td>n=3</td></tr><tr><td>V1+V4</td><td>x1</td><td>x1</td><td></td><td></td><td>n=2</td></tr><tr><td rowspan="3"></td><td>% hydrogel<br>medium</td><th colspan="2">100%</th><th colspan="2">50%</th><td></td></tr><tr><td></td><th>serum</th><th>no serum</th><th>serum</th><th>no serum</th><td></td></tr><tr><td>A4-LN</td><td>x1</td><td>x7</td><td>x1</td><td>x1</td><td>n=10</td></tr><tr><td rowspan="2">Peptigel</td><td>A4-GFO</td><td></td><td>x1</td><td></td><td></td><td>n=1</td></tr><tr><td>A4-LN+A4-GFO</td><td></td><td>x1</td><td></td><td></td><td>n=1</td></tr><tr><td>TrueGel3D</td><td>TRUE1</td><td></td><td>x3</td><td></td><td></td><td>n=3</td></tr></tbody></table>
**1- Cell culture and media**

Two mouse Embryonic Stem Cell (mESC) lines from different genetic backgrounds were used: mESC CD1-2 (Strain RjOrl:SWISS; derived in the lab) and mESC R1 (Strain 129/Sv; (1)). Prior to rosette production, stem cells were cultured in 2i LIF medium, a defined serum-free medium composed of N2B27 supplemented with Leukemia Inhibitory Factor (LIF) and two small molecules inhibitors (Tables A-1 and A-2: (2)). Cells were cultured at 37°C and 5% CO2.

**2- 3D culture into hydrogels**

The protocol for producing 3D rosette structures from stem cells is based on the work of Ivan Bedzhov and Magdalena Zernicka-Goetz (3).

**Hydrogels:** We used Geltrex™ from Gibco (equivalent to Matrigel) as a positive reference. Eight animal-free hydrogels from four suppliers were tested (see Table B for details). We followed the procedures provided and the recommendations of the technical services. The hydrogels were diluted to have a stiffness of approximately 400 to 2000 Pa, equivalent to Geltrex™ conditions.

**Hydrogel supports:** For gel drop/dome culture, two types of imaging-compatible culture support were used: (i) to optimize the immunostaining process, hydrogels were deposited on glass coverslips in 4-well or 24-well plates; (ii) to enable process miniaturization, we utilized Ibidi Angiogenesis plates with 15 wells of 50µl. Hydrogels stuck easily to substrates except for Vitrogel. For the latter, coating with Polylysine-A was used to increase adhesion to glass or plastic.

**Cell preparation:** Cells were dissociated using TrypLE Express (#12604013 GIBCO), a recombinant enzyme with no animal-derived components, for 3 to 5 minutes at 37°C. A single-cell suspension was then obtained by gentle mechanical dissociation. Centrifugation of a sufficient number of cells was performed to achieve a final concentration of 800–1,000 cells/µl in the hydrogel droplets. Several droplet sizes were tested (4, 5, 8, 10, and 15 µl) with no significant differences in growth. A volume of 8 µl was chosen for the culture tests, except for Peptigel™, which viscosity makes it difficult to deposit small volume droplets. For tests comparing Geltrex and PeptiGel, the droplet volume was 15 µl.

**Differentiation medium:** Two types of media were used: a DMEM-based medium with 15% foetal calf serum (FCS) (Supdata Table A-4) and a serum-free N2B27-based medium (Supdata Table A-1, A-3). At 24 hours, half of the medium was renewed. For 72h serum-free cultures, medium was replaced with N2B27 supplemented with Activin A (20 ng/ml) and FGF2 (12 ng/ml).

**Geltrex:** All manipulations and materials are kept at 4°C to avoid Geltrex polymerisation. Cell pellet was resuspended in cold Geltrex and quickly distributed into 8µL droplets. The culture dishes are inverted and allowed to polymerize 10 minutes at 37°C. The drops are then covered with warm medium.

**VitroGel:** the cell pellet was resuspended in culture medium at room temperature and mixed with Vitrogel (50/50 by volume) and divided into 8µL droplets. Polymerization took 20 minutes at room temperature. The droplets were then covered with warm medium. Medium was replaced one hour later.

**Peptigel:** at room temperature, Peptigel was used either pure or diluted in water at 50%. The cell pellet was resuspended in culture medium in a volume of 1/10th to 1/5th of the final volume of the Peptigel-cell mixture. This small amount of medium provides the ions necessary for polymerization. The cell suspension was then carefully mixed with the Peptigel to avoid bubbles, and the mixture quickly divided into 15µL droplets and incubated at 37°C for 5 minutes to polymerize. The droplets were then covered with medium. Within the next hour, medium was replaced again three times.
**TrueGel3D:** the components were reconstituted according to the provided procedure. The cell pellet was resuspended in medium in a volume representing 20% of the final one. It is then mixed at room temperature with 72% degradable RGD polymer and 8% degradable CD cell crosslinker. The mix remains liquid for 1-4 minutes and will then begin to form a gel. Therefore, the mix has to be dispensed quickly. Twenty to thirty minutes at 37°C were necessary to fully polymerize the droplets. After that, medium was added and changed again after 1 hour.

### 3- 3D-structures immunostaining

At 24h, 48h or 72h, 3D cultures were fixed overnight in 4% PFA at 4°C, then kept in PBS until use. For immunostaining, they were permeabilized with 0.3% Triton X-100 20 min at room temperature (RT) and then blocked in PBS with 2% BSA for 1h at RT. Incubation with primary antibodies was performed overnight at 4°C. After 3 rinses in PBS for 15-30 min, they were incubated for 1h at RT with fluorescent secondary antibodies along with DAPI (for DNA staining) and phalloidin (for F-actin staining) (Table C).

### 4- Image acquisition

Fluorescence images were acquired using an ApoTome system on ZEISS Axio Observer.Z1 microscope with 20x objectives (Plan Apochromat, NA 0.8) coupled with camera Axiocam MRm and Axiovision software. Images were merged and edited with Zen software (Zeiss). Background was reduced using brightness and contrast adjustments applied to the whole image. Cell counting within rosettes was done with ImageJ software and Cell counter plugin.

## Table A- MEDIA

### A-1- N2B27 base

Recipe for 1000ml. Can be aliquoted and stored at - 80°C

<table><thead><tr><td>REAGENT</td><td>SUPPLIER</td><td>VOLUME</td><td>FINAL CONCENTRATION</td></tr></thead><tbody><tr><td>DMEM/F12</td><td>Thermo Fisher - 21331-020</td><td>487 ml</td><td></td></tr><tr><td>Neurobasal</td><td>Thermo Fisher - 21103-049</td><td>487 ml</td><td></td></tr><tr><td>B27 (50X)</td><td>Thermo Fisher - 17504-044</td><td>10 ml</td><td>0.5X</td></tr><tr><td>N2 (200x)</td><td>Thermo Fisher - 17502-048</td><td>5 ml</td><td>1X</td></tr><tr><td>Glutamax 200mM</td><td>Thermo Fisher - 35050-061</td><td>10 ml</td><td>2mM</td></tr><tr><td>β-mercaptoethanol 50mM</td><td>Thermo Fisher - 31350-010</td><td>1 ml</td><td>50μM</td></tr></tbody></table>

### A-2 - N2B27 + 2i/LIF :

<table><thead><tr><td>REAGENT</td><td>SUPPLIER</td><td>VOLUME</td><td>FINAL CONCENTRATION</td></tr></thead><tbody><tr><td>N2B27 base</td><td></td><td>14 ml</td><td></td></tr><tr><td>PD 0325901 (10mM stock in DMSO)</td><td>Axon 1408</td><td>1μL</td><td>0.7μM</td></tr><tr><td>CHIR99021 (10mM stock in DMSO)</td><td>Axon - 1386</td><td>3.5μL</td><td>2.5μM</td></tr><tr><td>LIF (1000UI)</td><td>Cell Guidance Systems - GFM200</td><td>10μL</td><td>700UI</td></tr></tbody></table>

### A-3 - N2B27 + Activin/FGF2

<table><thead><tr><td>REAGENT</td><td>SUPPLIER</td><td>VOLUME</td><td>FINAL CONCENTRATION</td></tr></thead><tbody><tr><td>N2B27 base</td><td></td><td>10ml</td><td></td></tr><tr><td>Activin A (20μg stock in PBS-BSA 0.1%)</td><td>Cell Guidance Systems - GFH6</td><td></td><td>20ng/ml</td></tr><tr><td>FGF2 (100μg stock in PBS-BSA 0.1%)</td><td>Qkine - QK053</td><td></td><td>12ng/ml</td></tr></tbody></table>
<table><caption>A-4 - DMEM-SVF 15%- β-mercaptoethanol 50μM</caption><thead><tr><td>REAGENT</td><td>SUPPLIER</td><td>VOLUME</td><td>FINAL CONCENTRATION</td></tr></thead><tbody><tr><td>DMEM</td><td>Thermo Fisher</td><td>8.5ml</td><td></td></tr><tr><td>Fetal Bovine Serum</td><td>HyClone Cytiva SH30070.03E</td><td>1.5ml</td><td>15%</td></tr><tr><td>β-mercaptoethanol 50mM</td><td>Thermo Fisher - 31350-010</td><td>0.01 ml</td><td>50μM</td></tr></tbody></table>

## B - Gels

<table><thead><tr><th>HYDROGEL</th><th>SUPPLIER</th><th>Catalog N°</th></tr></thead><tbody><tr><td>Animal origin</td><td></td><td></td></tr><tr><td>Geltrex™</td><td>Thermo Fisher- Gibco</td><td>A14133-02</td></tr><tr><td>Xeno-free - animal origin-free</td><td></td><td></td></tr><tr><td>VitroGel 3D high concentration unmodified (polysaccharide base)</td><td>The Well BioScience</td><td>TWG001</td></tr><tr><td>Kit VitroGel™ VHM04-k functionalised for organoides culture N°1-N°2-N°3-N°4 (polysaccharide base)</td><td>The Well BioScience</td><td>VHM04-1S</td></tr><tr><td>Peptigel™ Laminin YiGSR (dextran base)</td><td>CellGuidance Systems</td><td>A4-LN</td></tr><tr><td>Peptigel™ Collagen GFOGER (dextran base)</td><td>CellGuidance Systems</td><td>A4-GFO</td></tr><tr><td>TrueGel3D™ Hydrogel Kit (dextran base)</td><td>Sigma Aldrich</td><td>TRUE1</td></tr></tbody></table>

## C - Antibodies - Dye

<table><thead><tr><td>Name</td><td>Company</td><td>Host</td><td>Ref.</td><td>Dilution</td></tr></thead><tbody><tr><td>Oct-3/4</td><td>R&amp;D Systems</td><td>Goat</td><td>AF1759</td><td>1/200</td></tr><tr><td>Podocalyxin (PODXL)</td><td>R&amp;D Systems</td><td>Rat</td><td>MAB1556</td><td>1/100</td></tr><tr><td>Phalloidine Alexa Fluor™ 647</td><td>Invitrogen</td><td></td><td>A22287</td><td>1/400</td></tr><tr><td>DAPI</td><td>Sigma Aldrich</td><td></td><td>D9542</td><td>5 µg/mL</td></tr><tr><td>Fluorescein (FITC) AffiniPure® Donkey Anti-Goat IgG (H+L)</td><td>Jackson Immuno Research</td><td></td><td>705-095-147</td><td>1/400</td></tr><tr><td>Cy™3 AffiniPure® Donkey Anti-Rat IgG (H+L)</td><td>Jackson Immuno Research</td><td></td><td>712-165-153</td><td>1/400</td></tr><tr><td>Rhodamine (TRITC) AffiniPure® Donkey Anti-Mouse IgG (H+L)</td><td>Jackson Immuno Research</td><td></td><td>715-025-151</td><td>1/400</td></tr></tbody></table>