Endovascular Biopsy: Evaluating the Feasibility of Harvesting Endothelial Cells Using Detachable Coils

The absence of safe and reliable methods to harvest vascular tissue in situ limits the discovery of the underlying genetic and pathophysiological mechanisms of many vascular disorders such as aneurysms. We investigated the feasibility and comparable efficacy of endothelial cell collection using a spectrum of endovascular coils. Nine detachable coils ranging in k coefficient (0.15–0.24), diameter (4.0 mm–16.0 mm), and length (8.0 cm–47.0 cm) were tested in pigs. All coils were deployed and retrieved within the iliac artery of pigs (three coils/pig). Collected coils were evaluated under light microscopy. The total and endothelial cells collected by each coil were quantified. The nucleated cells were identified by Wright-Giemsa and DAPI stains. Endothelial and smooth muscle cells were identified by CD31 and α-smooth muscle actin antibody staining. Coils were deployed and retrieved without technical difficulty. Light microscopy demonstrated sheets of cellular material concentrated within the coil winds. All coils collected cellular material while five of nine (55.6%) coils retrieved endothelial cells. Coils collected mean endothelial cell counts of 89.0±101.6. Regression analysis demonstrated a positive correlation between increasing coil diameter and endothelial cell counts (R2 = 0.52, p = 0.029). Conventional detachable coils can be used to harvest endothelial cells. The number of endothelial cells collected by a coil positively correlated with its diameter. Given the widespread use of coils and their well-described safety profile their potential as an endovascular biopsy device would expand the availability of tissue for cellular and molecular analysis.

Download Full-text

Endovascular biopsy: Technical feasibility of novel endothelial cell harvesting devices assessed in a rabbit aneurysm model

Interventional Neuroradiology ◽

10.15274/inr-2014-10103 ◽

2015 ◽

Vol 21 (1) ◽

pp. 120-128 ◽

Cited By ~ 4

Author(s):

Daniel L Cooke ◽

Diana Bauer ◽

Zhengda Sun ◽

Carol Stillson ◽

Jeffrey Nelson ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Univariate Analysis ◽

Comparable Efficacy ◽

Surface Finishing ◽

Vascular Endothelial ◽

Cell Counts ◽

Aorta Diameter ◽

Aneurysm Model ◽

Endothelial Cell Counts

The lack of safe and reliable methods to sample vascular tissue in situ limits discovery of the underlying genetic and pathophysiological mechanisms of many vascular disorders, including aneurysms. We investigated the feasibility and comparable efficacy of in vivo vascular endothelial cell sampling using a spectrum of endovascular devices. Using the rabbit elastase carotid aneurysm model we evaluated the performance of existing aneurysmal coils, intracranial stents, and stent-like devices to collect vascular endothelial cells. Additionally, we modified a subset of devices to assess the effects of alterations to coil pitch, coil wire contour, and stent surface finishing. Device performance was evaluated by (1) the number of viable endothelial cells harvested, (2) the degree of vascular wall damage analyzed using digital subtraction angiography and histopathological analysis, and (3) the ease of device navigability and retrieval. Isolated cells underwent immunohistochemical analysis to confirm cell type and viability. Coil and stent specifications, technique, and endothelial cell counts were tabulated and statistical analysis performed. Using conventional detachable-type and modified aneurysm coils 11 of 14 (78.6%) harvested endothelial cells with a mean of 7.93 (±8.33) cells/coil, while 15 of 15 (100%) conventional stents, stent-like devices and modified stents harvested endothelial cells with a mean of 831.33 (±887.73) cells/device. Coil stiffness was significantly associated with endothelial cell count in univariate analysis (p = 0.044). For stents and stent-like devices univariate analysis demonstrated stent-to-aorta diameter ratios (p = 0.001), stent length (p = 0.049), and the use of a pulling retrieval technique (p = 0.019) significantly predictive of endothelial cell counts, though a multivariate model using these variables demonstrated only the stent-to-aorta diameter ratio (p = 0.029) predictive of endothelial cell counts. Modified devices did not significantly impact harvesting. The efficacy and safety of existing aneurysm coils, intracranial stents and stent-like devices in collecting viable endothelial cells was confirmed. The technique is reproducible and the quantity and quality of collected endothelial cells is adequate for targeted genetic analysis.

Download Full-text

We don’t graft as many endothelial cells as we think (Part 1): what early post-operative endothelial cell counts tell us

Acta Ophthalmologica ◽

10.1111/j.1755-3768.2012.t108.x ◽

2012 ◽

Vol 90 ◽

pp. 0-0

Author(s):

C NEFZAOUI ◽

M TRONE ◽

N CAMPOLMI ◽

S ACQUART ◽

C THEILLIERE ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Cell Counts ◽

Endothelial Cell Counts

Download Full-text

Effects of Mitomycin C on Corneal Endothelial Cell Counts in Pterygium Surgery: Role of Application Location

American Journal of Ophthalmology ◽

10.1016/j.ajo.2010.09.014 ◽

2011 ◽

Vol 151 (3) ◽

pp. 488-493 ◽

Cited By ~ 11

Author(s):

Ahmad Kheirkhah ◽

Ali Izadi ◽

Mohammad Yaser Kiarudi ◽

Rahman Nazari ◽

Hesam Hashemian ◽

...

Keyword(s):

Endothelial Cell ◽

Mitomycin C ◽

Corneal Endothelial Cell ◽

Cell Counts ◽

Pterygium Surgery ◽

Endothelial Cell Counts

Download Full-text

Correlation of Histologic Corneal Endothelial Cell Counts With Specular Microscopic Cell Density

Archives of Ophthalmology ◽

10.1001/archopht.1992.01080200126039 ◽

1992 ◽

Vol 110 (8) ◽

pp. 1146 ◽

Cited By ~ 28

Author(s):

K. Keven Williams

Keyword(s):

Endothelial Cell ◽

Cell Density ◽

Corneal Endothelial Cell ◽

Cell Counts ◽

Endothelial Cell Counts

Download Full-text

The Damage Sensory Molecule TRPA1 Positively Regulates Endogenous Thymic Regeneration after Damage

Blood ◽

10.1182/blood.v130.suppl_1.67.67 ◽

2017 ◽

Vol 130 (Suppl_1) ◽

pp. 67-67

Author(s):

Kimon Argyropoulos ◽

Enrico Velardi ◽

Jennifer Tsai ◽

Amina Lazrak ◽

Lorenz Jahn ◽

...

Keyword(s):

Lipid Peroxidation ◽

Endothelial Cells ◽

Endothelial Cell ◽

Epithelial Cells ◽

Thymic Epithelial Cells ◽

Lipid Peroxidation Products ◽

Positive Effects ◽

Damage Sensing ◽

Cell Counts ◽

Thymic Regeneration

Abstract The thymus is extremely sensitive to exogenous insults but has a remarkable capacity to regenerate which is lost with age. Reactive oxygen species (ROS) accumulate early after tissue damage and despite their toxic potential, ROS and their byproducts (such as lipid peroxidation products-LPPs) can act as regeneration signals by activating membrane or intracellular sensors and subsequent stress-response signalling pathways. Using Sublethal Total Body Irradiation (SL-TBI) as a model of acute thymic injury, we found a rapid accumulation of thymic ROS as well as lipid peroxidation products on cell membranes after SLTBI (Figure 1A&B). The damage-sensing ion channel Transient Receptor Potential cation channel family A member 1 (TRPA1) represents one of the major damage sensing receptors that can mediate cellular responses to oxidative stress mediators, such as LPPs. Using immunofluorescence (IF) microscopy we found that TRPA1 is enriched in the thymic medulla. Interestingly, although TRPA1 has been classically identified in nociceptive fibers, the major TRPA1 expressing structures in the thymus were not nerve fiber terminals, but primarily thymic endothelial cells (Figure1C), fibroblasts and subsets of epithelial cells. We have recently demonstrated that thymic endothelial cells can regulate regeneration through secretion of BMP-4, which can enhance Foxn1 expression and proliferation of thymic epithelial cells. In order to assess the functional role of TRPA1 in thymic regeneration after injury, we utilized TRPA1 knockout (TRPA1-/-) mice and quantified thymic reconstitution after SL-TBI. TRPA1-/- mice had significantly lower thymic cellularity compared to their age- and sex-matched WT controls, suggesting an association between TRPA1 deficiency and delayed endogenous thymic recovery (Figure 1D). The major deficit in thymocyte counts primarily affected double negative-4 (DN4), double positive (DP) and CD4+ single positive (SP-CD4+) thymocyte numbers. The thymic stroma of TRPA1-/- mice had lower endothelial cell and fibroblast counts (Figure 1D). In accordance with these findings drinking water administration of the TRPA1 agonist Allyl-Isothiocyanate (AITC), resulted in enhanced thymic regeneration after radiation exposure. Besides its positive effects on thymocyte counts, AITC significantly augmented endothelial cell counts after irradiation (Figure 1E). In conclusion these results suggest that TRPA1 plays a non-redundant role in thymic regeneration and that exogenous TRPA1 stimulation can enhance immune recovery after damage. Disclosures van den Brink: Seres: Research Funding; Jazz Pharmaceuticals: Consultancy; PureTech Health: Consultancy; Therakos Institute: Other: Speaking engagement.

Download Full-text

The Effect of Successful Rebubbling After Descemet Stripping Automated Endothelial Keratoplasty on Endothelial Cell Counts

Cornea ◽

10.1097/ico.0b013e3181cb40f6 ◽

2010 ◽

Vol 29 (8) ◽

pp. 878-882 ◽

Cited By ~ 9

Author(s):

Raneen Shehadeh Mashor ◽

Igor Kaiserman ◽

Nikhil Kumar ◽

Wiwan Sansanayudh ◽

David Rootman

Keyword(s):

Endothelial Cell ◽

Endothelial Keratoplasty ◽

Cell Counts ◽

Endothelial Cell Counts

Download Full-text

Electrical activation of endothelium evokes vasodilation and hyperpolarization along hamster feed arteries

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.280.1.h160 ◽

2001 ◽

Vol 280 (1) ◽

pp. H160-H167 ◽

Cited By ~ 67

Author(s):

Geoffrey G. Emerson ◽

Steven S. Segal

Keyword(s):

Endothelial Cells ◽

Smooth Muscle ◽

Endothelial Cell ◽

Smooth Muscle Cells ◽

Cell Damage ◽

Muscle Cells ◽

Sympathetic Nerves ◽

Retractor Muscle ◽

Receptor Interactions ◽

Feed Arteries

Endothelial cells are considered electrically unexcitable. However, endothelium-dependent vasodilators (e.g., acetylcholine) often evoke hyperpolarization. We hypothesized that electrical stimulation of endothelial cells could evoke hyperpolarization and vasodilation. Feed artery segments (resting diameter: 63 ± 1 μm; length 3–4 mm) of the hamster retractor muscle were isolated and pressurized to 75 mmHg, and focal stimulation was performed via microelectrodes positioned across one end of the vessel. Stimulation at 16 Hz (30–50 V, 1-ms pulses, 5 s) evoked constriction (−20 ± 2 μm) that spread along the entire vessel via perivascular sympathetic nerves, as shown by inhibition with tetrodotoxin, ω-conotoxin, or phentolamine. In contrast, stimulation with direct current (30 V, 5 s) evoked vasodilation (16 ± 2 μm) and hyperpolarization (11 ± 1 mV) of endothelial and smooth muscle cells that conducted along the entire vessel. Conducted responses were insensitive to preceding treatments, atropine, or N ω-nitro-l-arginine, yet were abolished by endothelial cell damage (with air). Injection of negative current (≤1.6 nA) into a single endothelial cell reproduced vasodilator responses along the entire vessel. We conclude that, independent of ligand-receptor interactions, endothelial cell hyperpolarization evokes vasodilation that is readily conducted along the vessel wall. Moreover, electrical events originating within a single endothelial cell can drive the relaxation of smooth muscle cells throughout the entire vessel.

Download Full-text