Name: Establishing Primary In Vitro Culture of Leptomeningeal Lymphatic Endothelial Cells (LLECs)
Uploaded: 2023-09-08T14:55:00
Description: Watch this Scientific Journal Video about Establishing Primary In Vitro Culture of Leptomeningeal Lymphatic Endothelial Cells LLECs at JoVE.com

establishing primary in vitro culture of leptomeningeal lymphatic endothelial cells (llecs)

Establishing In Vitro LLEC Cultures Using Magnetic Cell Selection

The newly discovered leptomeningeal lymphatic endothelial cells (LLECs) form a meshwork of individual cells within the leptomeninges, exhibiting a distinct distribution pattern when compared to peripheral lymphatic endothelial cells1,2. The cellular functions and clinical implications associated with LLECs remain largely uncharted territory. In order to pave the way for functional research on LLECs, it is imperative to establish an in vitro model for their study. Therefore, this study has devised a comprehensive protocol for the isolation and primary culture of LLECs.
Mice are the preferred animal model due to their suitability for genetic manipulation in disease research. Previous studies have successfully isolated lymphatic endothelial cells from various mouse tissues, including lymph nodes3, mesenteric tissue4, dermal tissue5, collecting lymphatics6, and lung tissue7. These isolation procedures have primarily relied on techniques such as magnetic-activated cell sorting (MACS) and flow cytometry sorting8,9,10. Additionally, research efforts have led to the establishment of rat arachnoid cell lines and rat lymphatic capillary cell lines11,12. Despite the existence of explant culture techniques for leptomeninges13, there exists an urgent need for a standardized protocol for the isolation and culture of LLECs. Consequently, this study has successfully harvested and cultured LLECs by meticulously dissociating leptomeninges under the guidance of a microscope and promoting LLECs expansion through the use of vascular endothelial growth factor-C (VEGF-C). The distinctive marker for lymphatic endothelial cells is lymphatic vessel hyaluronic receptor-1 (LYVE-1)14. This multi-step protocol selectively isolates LYVE-1-positive LLECs using MACS and subsequently verifies their purity through flow cytometric analysis and immunofluorescent staining.
The primary steps of this multi-step protocol can be summarized as follows: flask coating, dissociation of leptomeninges, enzymatic digestion of leptomeninges, cell expansion, magnetic cell selection, and subsequent culture of LLECs. Finally, the purity of the isolated LLECs is confirmed through flow cytometric analysis and immunofluorescent staining. The overarching aim of this study is to present a reproducible, multi-step protocol for the isolation of LLECs from mouse leptomeninges and their subsequent in vitro culture. This protocol is poised to greatly facilitate investigations into the cellular functions and clinical implications of LLECs.

Author Spotlight: Unveiling Cellular Functions and Potential Clinical Implications of Leptomeningeal Lymphatic Endothelial Cells 

Harvest and Primary Culture of Leptomeningeal Lymphatic Endothelial Cells

This protocol is designed for areas of by other researchers only interested where established the multi procedure to and cultural primary areas Our protocol ultimately led to the establishment of our primary culture of area CS with a purity level exceeding 95%There is currently no existing protocol for harvesting and culturing Our results paved the way for further investigating the similar function of LLECS in virtual. At RUC, our recent discovery intracranial cellular population, the biological significance of RUC We will conduct further research on the cellular function and review its clinical implication.

Watch this Scientific Journal Video about Establishing Primary In Vitro Culture of Leptomeningeal Lymphatic Endothelial Cells LLECs at JoVE.com

Establishing Primary In Vitro Culture of Leptomeningeal Lymphatic Endothelial Cells (LLECs)  

Begin by attaching a magnetic separator to its stand. Connect a selection column to the magnetic separator and place a 70 micron cell strainer on top of the selection column. Place a 50 milliliter tube beneath the selection column to collect the flow.Once the mouse brain cells reach 80%confluency, aspirate the medium and rinse the cells with PBS. Add 0.25%trypsin to detach the adherence cells and incubate at 37 degrees Celsius for five minutes. Then add a stopping buffer.Centrifuge the cell suspension at 300 G for five minutes, and remove the supernatant. For antibody staining, resuspend 10 to the seven cells in 100 microliters of PBS. Then add 10 microliters of LYVE-1 antibody solution and mix thoroughly.Incubate the mixture for 30 minutes in the dark at four degrees Celsius. After incubation, centrifuge the cells and discard the supernatant. Then rinse the cells by adding one milliliter of PBS and centrifuging at 300 G for five minutes.For microbead labeling, resuspend the pellet in 100 microliters of PBS and 20 microliters of microbeads. Make swell and incubate for 30 minutes in the dark at four degrees Celsius. Then centrifuge the suspension and wash the pellet with one milliliter of PBS.Again, centrifuge and resuspend the pellet in four milliliters of PBS for magnetic negative exclusion. Pass the cell suspension through a 70 micron strainer to eliminate clumps. Prepare the selection column by rinsing it with three milliliters of PBS.Then add cell suspension into the selection column. Wash the column with three milliliters of PBS and collect LYVE-1 negative cells into a 50 milliliter tube. For magnetic positive selection, pipette six milliliters of PBS into the selection column.Then flush the magnetically labeled cells by firmly pushing the plunger into the selection column to obtain LYVE-1 positive LLECs. Next, centrifuge the positive cell suspension and remove the supernatant. Plate 10 to the fifth cells per square centimeter into a T25 flask with five milliliters of culture medium.Maintain the culture by replacing 50%of the medium every alternate day. When the cells reach 80%confluency, detach them as demonstrated previously before performing cell passage. Flow cytometry analysis revealed that the percentage of LYVE-1 positive cells in passage two was not significantly different from passage three after MACS, indicating a purity greater than 95%Immunofluorescent staining confirmed co-staining of LYVE-1 with PDPN, VEGFR-3 and PROX1, establishing the identity of LLECs.LYVE-1 positive cells did not express F48 and platelet derived growth factor beta, effectively distinguishing LLECs from macrophages and fibroblasts. Leptomeningeal cells before MACS displayed heterogeneous morphology ranging from round spheres to fused fiber shapes. However, post MACS, LLECs exhibited typical endothelial-like features such as spindle and cobblestone shapes.

Research

JoVE Journal

Neuroscience

Leptomeningeal lymphatic endothelial cells (LLECs) are a recently discovered intracranial cellular population with a unique distribution clearly distinct ...