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At least 523 records · Page 29Linked to original sources
PubMed2003

CD44 mediates polymorphonuclear leukocyte motility on hyaluronan.

OBJECTIVE: To investigate the behavior of polymorphonuclear (PMN) leukocytes on the extracellular matrix carbohydrate component, hyaluronan (HA), in the presence and absence of the chemokine, interleukin-8 (IL-8). METHODS: The present study was conducted at the Department of Hematology, University of Liverpool, United Kingdom, between the period 2000 to 2001. Polymorphonuclear cells were isolated from whole venous blood using Mono-Poly-Resolving Medium. Purified PMN were added alone or with IL-8 to HA-coated plates and the behavior of these cells monitored by time-lapse video microscopy over a period of 40 minutes. For the identification of surface receptor(s) mediating PMN migration on HA, PMN were incubated with blocking and non-blocking antibodies against cluster of differentiation 44 (CD44) and Receptor for Hyaluronan Mediated Motility (RHAMM) prior to addition to HA-coated surfaces. RESULTS: Approximately 55% of PMN were found to interact and migrate on HA-coated plates with a mean speed of 6.4 +/- 0.7 mm/min. Addition of IL-8 reduced both the percentage moving cells (7.5%) and the average speed of the remaining moving cells (2.0 +/- 0.3 mm/min). The inhibitory effect of IL-8 on PMN migration was associated with reorganization of the cytoplasmic fibrillar form of actin. Anti-CD44 blocking antibody substantially reduced the speed of PMN (2.5 +/-0.9 mm/min), while non-blocking anti-CD44 and anti-RHAMM antibodies had no effect. CONCLUSION: The present study demonstrates for the first time that PMN are able to interact and migrate on the widely distributed extracellular matrix component, HA, using the cell surface receptor, CD44. Such interaction is modified by the chemokine, IL-8, in a way that optimizes the host defense against invading pathogens.

Cell Movement↗
PubMedDate not supplied

Head and neck squamous cell carcinoma cell lines are highly sensitive to the new taxanes, BMS-184476, BMS-188797, in vitro.

BACKGROUND: The development of synthetic taxanes targets at increasing solubility of the drug, improved clinical efficacy and reduced side-effects. We evaluated the sensitivity of head and neck squamous cell carcinoma cell lines to BMS-184476 and BMS-188797 in vitro. MATERIALS AND METHODS: The effects of paclitaxel and the synthetic taxanes were tested on six recently established cell lines (3 oral cavity SCC, 3 laryngeal SCC) using the 96-well plate clonogenic assay. The IC50 values, corresponding to the mean inactivation dose, were obtained from the dose response curves. RESULTS: All tested cell lines were considerably more sensitive to both synthetic taxanes compared to paclitaxel. As a rule, the IC50 concentration for paclitaxel was 4-5.5 times higher than that of BMS-184476 or BMS-188797. The sensitivity to these drugs varied from cell line to cell line, and time lapse video microscopy showed a mitotic arrest with subsequent apoptosis after four hours with BMS-188797. CONCLUSION: These results indicate that the synthetic taxanes could be useful clinically and warrant in vitro testing in combined modality models, like concurrent chemoradiation.

Carcinoma, Squamous Cell↗
PubMed2005

Functional genomic analysis of cell division by endoribonuclease-prepared siRNAs.

The emergence of RNA interference (RNAi) technology has revolutionized functional genomic analyses in cell biology, including the study of cell division. In particular, the introduction of short interfering RNAs (siRNAs) and short hairpin RNAs (shRNAs) has facilitated loss-of-function studies in mammalian cell lines. We have pioneered the rapid and cost-efficient generation of libraries of endoribonuclease-prepared short interfering RNAs (esiRNAs) for large-scale genetic screens in mammalian tissue culture cells. Our first pilot screen of 5305 genes in human HeLa cells identified novel genes required for cell division, establishing esiRNA as a sophisticated method for loss-of-function screens. Future genome-wide studies with esiRNA, using image-based assays and video microscopy, will help provide novel insights on the molecular mechanisms that govern cell division in mammalian cells.

Animals↗
PubMed2006

[Mobile reticular organization of plastids and mitochondria in plant cells].

Results of confocal, fluorescent and video microscopy of plant cell organelles and of stromule network uniting them are reviewed. The vast information on the structure of stromules, their mobility, proposed functions and development has been analyzed, in addition to factors stimulating and suppressing this development. Structural similarity between the network of stromules in living cells, observed by confocal fluorescence microscopy, and the endoplasmic reticulum, seen on micrographs of preparations fixed for electron microscopy is discussed. As a result of this discussion, a conclusion is made with regard to the identity of these endomembranous networks. The intercellular symplastic organization is shown for both networks in plant tissues. The existence of a common transport and trophic compartment is proposed that includes organelles, intercellular endoplasmic reticulum and its derivatives, phloem and xylem. The trophic system development might have been induced in the course of endosymbiogenesis with some bacterial precursors of organelles.

Cytoplasm↗
PubMed1995

Growth cones are actively influenced by substrate-bound adhesion molecules.

As axons advance to appropriate target tissues during development, their growth cones encounter a variety of cell adhesion molecules (CAMs) and extracellular matrix molecules (ECM molecules). Purified CAMs and ECM molecules influence neurite outgrowth in vitro and are thought to have a similar function in vivo. For example, when retinal ganglion cell (RGC) neurons are grown on different CAM and ECM molecule substrates in vitro, their growth cones display distinctive morphologies (Payne et al., 1992). Similarly, RGC growth cones in vivo have distinctive shapes at different points in the pathway from the eye to the tectum, suggesting the presence of localized cues that determine growth cone behaviors such as pathway selection at choice points. In this report, time-lapse video microscopy was utilized to examine dynamic transformations of RGC growth cones as they progressed from L1/8D9, N-cadherin, or laminin onto a different substrate. Contact made by the leading edge of a growth cone with a new substrate resulted in a rapid and dramatic alteration in growth cone morphology. In some cases, the changes encompassed the entire growth cone including those regions not in direct contact with the new substrate. In addition, the growth cones displayed a variety of behavioral responses that were dependent upon the order of substrate contact. These studies demonstrate that growth cones are actively affected by the substrate, and suggest that abrupt changes in the molecular composition of the growth cone environment are influential during axonal pathfinding.

Animals↗
PubMed1995

Regulation of lymphocyte pseudopodia formation by triggering the integrin alpha 4/beta 1.

Video microscopy and digital imaging were used to quantitatively analyze lymphocyte adhesion and formation of pseudopodia on the extracellular matrix protein fibronectin (FN). A morphology kinetics assay comparing pseudopodial extension values over a 24-h period showed that HPB-ALL T leukemic cells undergo a wave of morphologic change, returning to a round shape after 8 h. Using anti-alpha 4 and anti-alpha 5 mAbs and a panel of cell types that are single or double positive for expression of the alpha 4/beta 1 and alpha 5/beta 1 FN binding integrins, it was determined that cell adhesion to FN was influenced by both beta 1-integrins, whereas alpha 4/beta 1 was found to be the major FN receptor mediating pseudopodia extension. The protein kinase inhibitor staurosporine, the protein kinase C inhibitors calphostin C and chelerythrine, and the protein tyrosine kinase inhibitor herbimycin A blocked pseudopodial extension in HPB-ALL cells. In contrast, two cAMP-dependent protein kinase inhibitors H8 and H89 did not inhibit. Inhibitors of phospholipase A2, lipoxygenases, and cyclooxygenases could block formation of pseudopodia, yet had little or no effect on cell adhesion to FN. The preincubation of cells with arachidonic acid could prevent the inhibition mediated by the reversible phospholipase A2 inhibitor cibacron blue. We conclude that the formation of lymphocyte pseudopodia in response to FN can utilize the adhesive and signaling activities of the alpha 4/beta 1-integrin and the enzymatic activities of protein kinases and phospholipases.

Antibodies, Monoclonal↗
PubMed1994

Retinal axon divergence in the optic chiasm: dynamics of growth cone behavior at the midline.

To study how retinal ganglion cell axons diverge in the optic chiasm, the behavior of dye-labeled fibers was monitored in real time with video microscopy in an isolated preparation of embryonic mouse brain, with a focus on embryonic day 15-16. These real-time studies have revealed the dynamics of the growth of individual retinal axons, especially the tempo of extension and growth cone behaviors during divergence in the chiasm, a model for "decision" regions in developing pathways. Within the chiasm, retinal growth cones extend by saltatory growth, consisting of bursts of rapid advance alternating with pauses in extension. During pauses, growth cone appendages remain motile, and develop asymmetries prior to a change in the axis of growth. In a zone straddling the midline, retinal fibers, irrespective of destination, display long pauses for up to several hours, making small advances and retractions with no net extension. While crossed fibers ultimately progress through the midline, uncrossed fibers from inferior temporal retina develop wide-ranging branched growth cones, and then turn back to the ipsilateral side. Turns are effected by the selective retraction or micropruning of asymmetric foci of motile activity, and by the transformation of a backward-directed filopodium into a new growth cone. The behavior of retinal axons at the midline supports the hypothesis that this locus contains cues important for retinal axon divergence. Moreover, the observations of growth cone kinetics in the chiasm elucidate which growth cone forms seen in static preparations mediate growth cone turning, and suggest a model of axon navigation in decision regions in the intact nervous system.

Animals↗
PubMedDate not supplied

Cytoplasmic tutor: a program for teaching interpretation of a microscope-based laboratory test.

Antibodies to cytoplasmic antigens can be identified with a microscope-based indirect immunofluorescence assay that uses a mouse stomach-kidney substrate. The antibodies are diagnostic markers in chronic active hepatitis, primary biliary cirrhosis, pernicious anemia, and other autoimmune diseases. We describe the development and features of an image-based computer program for teaching medical technologists and other health care workers the proper interpretation of cytoplasmic fluorescence staining patterns. The program, called Cytoplasmic Tutor, is written in Microsoft Visual Basic for Windows and runs on an 80486 microcomputer. it is based on a library of digital images, with key features described by overlays of text. The images were collected and processed with a computer-based fluorescence video microscopy system assembled in our laboratory.

Animals↗
PubMed1996

Surface contraction and expansion waves correlated with differentiation in axolotl embryos. II. In contrast to urodeles, the anuran Xenopus laevis does not show furrowing surface contraction waves.

We have observed a number of contraction waves traversing the axolotl (Ambystoma mexicanum) embryo (a urodelan amphibian) from the midblastula transition up to at least neural tube closure, and wished to learn if similar "differentiation waves" appear on the popular laboratory anuran amphibian, the South African clawed toad, Xenopus laevis. Time lapse video microscopy showed that no contraction waves are visible on the surface of Xenopus from gastrulation through neurulation. It is possible that cell intercalations in the double-layered ectoderm of the Xenopus embryo are homologous to the surface waves in the single layered ectoderm of the axolotl embryo. In any case, a simple, universal correspondence between surface waves and induction phenomena and differentiation does not exist.

Ambystoma↗
PubMed1996

Fibrinogen mediates leukocyte-endothelium bridging in vivo at low shear forces.

In addition to preserving hemostasis, fibrinogen assembly on leukocytes mediates inflammatory responses and may aberrantly contribute to vascular injury. In this study, we used real-time intravital video microscopy in exposed rabbit mesentery to investigate the potential role of fibrinogen on leukocyte adherence mechanisms, in vivo. At physiologic concentrations of 0.15 to 0.5 mg/mL, human fibrinogen dose-dependently enhanced by threefold to fivefold the adhesion of chemoattractant-stimulated monocytic HL-60 cells to rabbit mesenteric endothelium, by acting as a bridging molecule between the two types. Fibrinogen-dependent intercellular bridging occurred in venules, but not in arterioles or capillaries (1), was optimal at reduced flow shear forces (range: 0.77 to 2.79 dyne/cm2) (2), and produced a firm attachment of monocytic cells to endothelium, rather than transient rolling (3). Consistent with this model, rabbit fibrinogen failed to support human leukocyte adhesion, while human fibrinogen enhanced monocytic cell attachment to rabbit endothelial cells in vitro, in a reaction indistinguishable from that observed with human endothelium. Antagonists of the recently described association of fibrinogen with intercellular adhesion molecule-1 (ICAM-1), including monoclonal antibodies (MoAbs) LB-2 or 2D5, or the fibrinogen gamma 3 peptide gamma Asn117-Ala133, blocked fibrinogen-dependent leukocyte-endothelium interaction in vitro or in vivo, respectively, while a control nonbinding antibody or the fibrinogen L10 peptide gamma Leu402-Val411 were ineffective. These data suggest that simultaneous assembly of fibrinogen on leukocytes and endothelial ICAM-1 provides a pathway of intercellular adhesion which may act in concert with beta 2 integrins to stabilize firm leukocyte attachment to endothelium, in vivo. Given the recognized role of fibrinogen as a major risk factor for atherosclerosis, this mechanism may directly contribute to thrombus formation and endothelial cell damage in vascular diseases.

Animals↗
PubMed1996

Types and activities of voltage-operated calcium channels change during development of rat pituitary neurointermediate lobe.

Cultures of pituitary neurointermediate lobe cells were established from rats aged 1, 12, and 42 days to identify the types and assess the activities of Ca2+ channels present in melanotropes, glial-like cells, and fibroblasts during development. Day 12 represents the time at which dopaminergic axons have become distributed throughout the lobe, glial cells begin to lose their radial orientation, and melanotropes robustly express the short isoform of the dopamine D2 receptor. Thus, we studied Ca2+ channels in relation to the event of innervation of melanotropes. Real-time fluorescence video microscopy, in the presence of pharmacological agents, which block L-, N-, P-, and T-type channels, was used as an indirect measurement of channel activity. Assessment of cell type was verified by triple-label fluorescence immunohistochemistry. In melanotropes, extracellular Ca2+ addition caused Ca2+ influx through omega-conotoxin GVIA-sensitive, N-type channels on days 1 and 12 but not on day 42. The K+ depolarization induced an increase in intracellular Ca2+ concentration in all age-groups. This effect was decreased by nifedipine, an L-type channel blocker, at all ages, and by omega-agatoxin IVa, a P-type blocker, only on day 42. These results demonstrate that the predominance of N- or P-type channels on melanotropes is age-dependent and can be correlated with other developmental changes. The T-type blocker, NiSO4, had no effect. In glial-like cells of all ages, extracellular Ca2+ addition resulted in an increase in intracellular Ca2+ concentration, which was inhibited only by NiSO4. The percentage of responsive glial-like cells was equally high in days 1 and 12 cultures, then declined by day 42. The K+ depolarization had no effect on glial-like cells. Fibroblasts did not respond significantly to extracellular Ca2+ or K+ depolarization, indicating little detectable activity by this methodology from functional voltage-operated Ca2+ channels.

Animals↗
PubMed1997

The establishment of peripheral sensory arbors in the leech: in vivo time-lapse studies reveal a highly dynamic process.

Pressure-sensitive (P) neurons located in the leech CNS form elaborate terminal arbors in the body wall of the animal during mid-embryogenesis. In the experiments discussed here, arbor development in the target region was studied in intact, unanesthetized leech embryos using time-lapse video microscopy of individual, fluorescently stained P neurons. Analysis of time-lapse recordings made over a period of several days revealed that arbor formation is a very dynamic process. At any particular time, most high-order terminal branches were either extending or retracting, in approximately equal numbers and at very similar rates. Many branches underwent several rounds of extension and retraction every hour. Net arbor growth occurred at a much lower rate than the extension and retraction rates of individual branches. Process retraction sometimes resulted in an apparent change in the topological order of processes. Significantly, the initiation of new branches was restricted to a few locations along the parent process, which were termed "hot spots." Moreover, the capacity to generate high-order branches correlated with parent process stability. The target region of the growing P cell arbor in the body wall was subsequently examined using confocal microscopy in fixed preparations. The arbor expanded between the longitudinal and circular muscle layers, a region occupied by small unidentified cells. Simultaneous imaging of the dye-labeled terminal arbor and the surrounding tissue at two different wavelengths suggested that the high-order processes were navigating around these cells, which sometimes forced the growing processes to assume a bent form. These observations suggest that the formation of the P cell arbor can be best described as a "dynamically unstable" process that is constrained by interactions with its environment.

Animals↗
PubMedDate not supplied

Mechanisms by which thrombolytic therapy results in nonuniform lysis and residual thrombus after reperfusion.

A transport-reaction model describing penetration of plasmin by diffusion and permeation into a dissolving fibrin gel was solved numerically to explore mechanisms that lead to the formation and growth of dissolution fingers through blood clots during thrombolytic therapy. Under conditions of fluid permeation driven by arterial pressures, small random spatial variations in the initial fibrin density within clots (+/-4 to 25% peak variations) were predicted by the simulation to result in dramatic dissolution fingers that grew in time. With in vitro experiments, video microscopy revealed that the shape of the proximal face of a fibrin gel, when deformed by pressure-driven permeation, led to lytic breakthrough in the center of the clot, consistent with model predictions of increased velocities in this region leading to cannulation. Computer simulation of lysis of fibrin retracted by platelets (where more permeable regions are expected in the middle of the clot due to retraction) predicted cannulation of the clot during thrombolysis. This residual, annular thrombus was predicted to lyse more slowly, because radial pressure gradients to drive inner clot permeation were quite small. In conjunction with kinetic models of systemic pharmacodynamics and plasminogen activation biochemistry, a two-dimensional transport-reaction model can facilitate the prediction of the time and causes of clot cannulation, poor reperfusion, and embolism during thrombolysis.

Biological Transport↗
PubMed1997

[Observations on organic components of thermal mud: morphohistochemical and biochemical studies on lipid components of mud of the Terme dei Papi (Laghetto del Bagnaccio, Viterbo). Chemical bases of the interpretation of biological and therapeutic actions of thermal mud].

In previous findings the lipidic fractions extracted acc. to Folch from the mature muds of the majority of the Italian thermal springs hot baths was studied, with the aim to identify the organic substrates of their therapeutical activity. The organic components of the "mature" peloids are produced by the metabolism of the microphytozooplankton growing spontaneously in the clay-substrate, in contact with the hot water. The Popes thermal springs (Bagnaccio's Lake) are characterised by an unique environmental situation, because the muds are naturally matured in the hot thermal water, but not in artificial baths. The morphohistochemical aspects of thermal algae growing in the Bagnaccio's lake have been studied by means of Computerised Optic Probe Video-Microscopy, using a not contact zoom objective 70-400x. Peloid types, both the "white" and the "black" contains yellow pigments, fragments of hyphae, monocellular algae, Diatomeae, Cyanophyceae and few other species. The biochemical aspects of the muds extracts are characterised by the presence of Phospholipids (PC, PE, PS, SP), a series of Hydrocarbons ranging from C30 to C38, Phytosterols (beta-sitosterol, Campesterol, Stigmasterol and traces of Cholesterol), Free Fatty Acids (Palmitic, Palmitoleic, Myristic, Stearic, Oleic and Linoleic, heptadecenoic and heptadecanoic) and Terpenes (beta-amirrhyne, 24-methylene-cyclo-arthanole). In our opinion, the therapeutic effects of the mature muds are related to its organic components, with special regards to Phospholipids, Phytosterols and Terpenes. The richness of these components in the Popes Thermal springs seems to be great interest in the dermatological and cosmetic applications, other then the traditional use.

Animals↗
PubMed1998

Segmentation of the vertebrate hindbrain: a time-lapse analysis.

The chick hindbrain starts from a simple and relatively uniform axis and becomes segmented into repeating units, called rhombomeres. The rhombomeres become sites of cell differentiation into specific neurons and the location from which neural crest cells emerge from the neural tube to form the peripheral nervous system, which has only been analyzed at distinct time points due to the lack of a method to watch the neural tube as it is shaped into segments. We have developed a whole-embryo explant culture system in order to study cell and tissue movements with time-lapse video microscopy. Quantitative analyses of the neural tube during its segmentation show that not all rhombomeres are shaped by the same mechanism. In the rostral hindbrain, or first three segments, rhombomeres are shaped by an expansion in the lateral width of the mid-rhombomere; either a smaller expansion or a constriction takes place at the rhombomere boundaries. In the caudal hindbrain, the rhombomere boundaries constrict more than the mid-rhombomere lateral widths increase or decrease, leading to the shaping of the segments. Throughout the segmentation process the rostrocaudal lengths of all rhombomeres remain nearly constant indicating that shape changes are influenced by lateral expansions and constrictions of the neural tube.

Animals↗
PubMed1998

[Intracellular calcium channels, hormone receptors and intercellular calcium waves].

The hormone-mediated intercellular Ca2+ waves were analyzed in multiplets of rat hepatocytes by video imaging of fura2 fluorescence. These multicellular systems are composed of groups of several cells (doublets to quintuplets) issued from the liver cell plate, a one cell-thick cord of about 20 hepatocytes long between portal and centrolobular veins. When the multiplets were homogeneously bathed with the glycogenolytic agonists vasopressin, noradrenaline, angiotensin II and ATP, they showed highly organized Ca2+ signals. Surprisingly, for a given agonist, the primary rises in intracellular Ca2+ concentration ([Ca2+]i) originated invariably in the same hepatocyte, then was propagated in a sequential manner to the nearest connected cells (cell 2, then 3, cell 4 in a quadruplet, for example). The sequential activation of the cells appeared to be an intrinsic property of multiplets of rat hepatocytes. The same sequence was observed at each train of oscillations occurring between cells. The order of [Ca2+]i responses was modified neither by repeated additions of hormones nor by the hormonal dose. The mechanical disruption of an intermediate cell did not prevent the activation of the next cell. These results suggest that each hepatocyte in the multiplet displays its own sensitivity to the hormone and that a gradient of sensitivity between each cell could be responsible for directing the intercellular Ca2+ wave. To test this hypothesis, we selectively isolated rat hepatocytes from periportal (PP) and perivenous (PV) areas of the liver cell plate. Periportal (PP) and perivenous (PV) rat hepatocyte suspensions were loaded with quin2/AM and hormonal responses were studied in a spectrofluorimeter. Noradrenaline, angiotensin II, and vasopressin-induced [Ca2+]i rises were greater in PV than in PP hepatocytes. In contrast, PP cells were more responsive than PV cells to ATP. The function of the InsP3 receptor (InsP3R) was also studied by measuring the InsP3-mediated 45Ca2+ release from permeabilized PP and PV hepatocytes. In permeabilized PP and PV hepatocytes, internal Ca2+ stores displayed the same loading-kinetics, the responses to InsP3 were similar, and the sizes of InsP3-sensitive compartment were not different. In a further study, we investigated by video microscopy in fura2-loaded multicellular systems of rat hepatocytes, the mechanisms controlling intercellular propagation of the Ca2+ wave and coordination of Ca2+ signals induced by the different hormones. Using focal microperfusion which allows local perfusion of any cell of the multiplet, rapid agonist removal during the Ca2+ response and microinjection, we found that second messengers and [Ca2+]i rises in one hepatocyte cannot trigger Ca2+ responses in connected adjacent cells, suggesting that diffusion across gap junctions, while required for coordination, is not sufficient by itself for the propagation of the intercellular Ca2+ wave. In addition, focal microperfusion and intermediate cell disruption experiments revealed very fine functional differences (hormonal delay, frequency of [Ca2+]i oscillations) between hormone-induced Ca2+ signals, even between two adjacent connected hepatocytes. Recent unpublished results performed in suspensions of PP and PV rat hepatocytes supported the view of a major role played by vasopressin receptors (V1a) in genesis and orientation of the Ca2+ wave. Vasopressin binding sites, V1a mRNAs detected by RNAse Protection Assay, and vasopressin-induced InsP3 production, were more abundant in PV than in PP cells. A gradient of hormone receptors could orientate the propagation of the Ca2+ wave in multicellular systems and in liver cell plate. These results suggest that the intercellular Ca2+ wave in multicellular systems of rat hepatocytes is propagated through mechanisms involving at least three factors. (ABSTRACT TRUNCATED)

Animals↗
PubMed1999

Platelet adhesion to human brain microvascular endothelial cells in vitro. Observation with video-enhanced contrast microscopy.

Employing video-enhanced contrast (VEC) microscopy and perfusion systems, we examined whether platelets adhere directly to human brain microvascular endothelial cells (HBEC) in vitro after thrombin treatment and whether adenosine diphosphate (ADP) or thromboxane A2-stimulated platelets adhere directly to HBEC at a low flow state in vitro. HBECs were cultured on a coverglass and put in the observation chamber of VEC microscopy. Following pretreatment with human alpha-thrombin 1.0 units/ml (n = 8) for 20 min, thrombin was thoroughly washed out. Platelet rich plasma (PRP) was perfused over HBEC at a low shear rate of 10 s(-1) for 30 min. Platelets adhered directly to thrombin-treated HBEC. Activated platelets by ADP (2 microM, n = 8) or thromboxane A2 (U-46619 10 microM, n = 5) were perfused over HBEC for 30 min and washed out. Platelets also adhered directly to HBEC. However, platelets did not adhere to HBEC when PRP only (n = 6) was perfused over HBEC for 30 min and washed out. Platelet adhesion directly to HBEC following thrombin treatment or platelet activation may play a pivotal role in secondary thrombus formation and microcirculatory disturbance in the ischemic brain.

Adenosine Diphosphate↗