Establishing primary endometrial stromal cell culture systems from hysterectomy specimens is a valuable biological technique and a crucial step prior to pursuing a vast array of research aims. Here, we describe two methods used to establish stromal cultures from surgically resected endometrial tissues of human patients.
Many efforts have been devoted to establish in vitro cell culture systems. These systems are designed to model a vast number of in vivo processes. Cell culture systems arising from human endometrial samples are no exception. Applications range from normal cyclic physiological processes to endometrial pathologies such as gynecological cancers, infectious diseases, and reproductive deficiencies. Here, we provide two methods for establishing primary endometrial stromal cells from surgically resected endometrial hysterectomy specimens. The first method is referred to as “the scraping method” and incorporates mechanical scraping using surgical or razor blades whereas the second method is termed “the trypsin method.” This latter method uses the enzymatic activity of trypsin to promote the separation of cells and primary cell outgrowth. We illustrate step-by-step methodology through digital images and microscopy. We also provide examples for validating endometrial stromal cell lines via quantitative real time polymerase chain reactions (qPCR) and immunofluorescence (IF).
The human uterus corpus is comprised of three layers, the perimetrium (or serosa), the myometrium, and the endometrium. Distinguishing each of these layers is an important step to establish endometrial cell lines. The perimetrium is the outer most layer of the uterus and composed of thin, serous cells. The myometrium is the thick, middle layer of the uterus and comprised of smooth muscle cells. The endometrium is identified as the inner layer of the uterus and includes epithelial and stromal cell populations.
The endometrium is further subdivided into the basalis layer whose stem cell population is hypothesized to repopulate the functionalis layer approximately every 28 days 1. The functionalis layer of the human endometrium undergoes significant biochemical and morphological changes in response to circulating hormones. These hormones are derived from the pituitary gland and the ovaries.
The coordinated production and release of hormones results in a reproductive cycle. The reproductive cycle is designed to prepare the endometrium for potential embryo implantation events. In humans, the reproductive cycle is known as “the menstrual cycle” and divided into three phases – proliferative, secretory, and menstrual. The proliferative phase involves the proliferation of the functionalis endometrial layer whereas the secretory phase is marked by functionalis maturation. Specifically, extracellular alterations, secretions, and cellular differentiation signal a potential implantation. If implantation does not occur before the end of the secretory phase, the functionalis endometrial layer is shed during the menstrual phase. The importance of menstruation and the events that trigger the shedding of the functionalis layer are still being debated. In humans, it has been posed that menstruation is the result of a specific mid-secretory phase differentiation event known as “spontaneous decidualization” 2. In this manuscript, we provide detailed methodology for both endometrial stromal cell isolation methods, and use a combination of immunofluorescence and digital images to demonstrate efficacy of these approaches. In addition, we apply a commonly used in vitro model of spontaneous decidualization to confirm endometrial stromal cell isolation.
Other groups have described and adapted methodology for the preparation of endometrial stromal cultures, most of which utilize collagenase 4,12,13,15-18. In this manuscript, we have provided methodology and evidence for two simplified primary endometrial stromal culture methods, both of which are utilized by our lab for economical reasons and the convenient availability of trypsin and/or a razor blade.
When comparing our two methods, both successfully generate viable primary cu…
The authors have nothing to disclose.
We thank the collaborative efforts of Dr. Thao Dang and members of her lab for use of their imaging and microscope equipment. We also thank the Biorepository and Tissue Research Facility (BTRF) core, Jeff Harper, and the residents at the University of Virginia for providing us with uterine tissue. We thank Karol Szlachta for the help with Schematic Overview.
0.25 Trypsin or 0.05% Trypsin | Hyclone | SH3023602 or SH30004202 | |
1.7 micro Centrifuge Tube | Genesee Scientific | 22-272A | |
1µl,20µl, 200ml and 1000µl Pipette | Genesee Scientific | 24-401,24-402, 24-412, 24-430 | |
15ml Conical Tube | Hyclone | 339650 | |
50ml Conical Tube | Hyclone | 339652 | |
6cm Cell Culture Dish | Thermo scientific | 12-556-002 | |
8 well Chambers | Thermo Scientific | AB-4162 | |
Acetate | Fisher scientific | C4-100 | |
AMV RT Enzyme/Buffer | Bio Labs | M077L | |
Bovine Serum Albumin (BSA) | Fisher Scientific | BP-1605-100 | |
Buffered Zinc Formalin | Thermo | 59201ZF | |
Charcoal strip FBS | Fisher | NC9019735 | |
Chloroform | Fisher Scientific | BP1145-1 | |
Cover slip | Fisher Brand | 12-544D | |
Cyclic AMP (cAMP) | Sigma | B7880 | |
DMEM/High Glucose | Hyclone | SH30243FS | |
dNTP | Bioline | BIO-39025 | |
Donkey Anti Goat -TRITC | Santa Cruz | SC-3855 | |
Donkey Serum | Jackson’s lab | 017-000-002 | |
E Cadherin Antibody | Epitomics | 1702-1 | |
Ethanol | Fisher Scientific | BP2818-1 | |
Fetal Bovine Serum (FBS) | Fisher Scientific | 03-600-511 | |
Fungizone Amphotericin B | Gibco | 15290-018 | |
GAPDH Probe | Life Technologies | HS99999905 | |
Glycogen | 5Prime | 2301440 | |
Goat Anti Mouse -FITC | Jackson’s Lab | 115-096-003 | |
Isopropanol | Fisher Scientific | BP2618-1 | |
Kanamycin | Fisher Scientific | BP906-5 | |
Medroxyprogesterone acetate (MPA) | Sigma | M1629 | |
MeOH (Methanol) | Fisher Scientific | A4-08-1 | |
Mounting Media (w/DAPI) | Vector Labratories | H-1500 | |
N6 DNA Oligos | Invitrogen | ||
Number 15 Scraper | BD | 371615 | |
Pan Cytokeratin Mouse mAB | Cell Signaling | 4545 | |
PBS (phosphate buffered saline) | Fisher Scientific | BP-399-4 | |
Penicillin-Streptomycin Glutamine Solution 100X | Hyclone | SV30082.01 | |
PML Anti Goat Anti body | Santa Cruz | SC-9862 | |
Primer(s) | Eurofins | ||
RPMI | Hyclone | SH30027FS | |
RPMI (Phenol free) | Gibco | 11835 | |
Sybr Green | Thermo Scientific | AB-4162 | |
Taqman | Thermo | AB-4138 | |
Trizol | Life Technologies | 15596018 | |
Vimentin Antibody | Epitomics | 4211-1 |