Biomedical subjects

G Ed Rainger

Publications and source records attributed to G Ed Rainger.

At least 19 recordsLinked to original sources

PubMed2006

Neutrophils are a key component of the antitumor efficacy of topical chemotherapy with ingenol-3-angelate.

Harnessing neutrophils for the eradication of cancer cells remains an attractive but still controversial notion. In this study, we provide evidence that neutrophils are required to prevent relapse of skin tumors following topical treatment with a new anticancer agent, ingenol-3-angelate (PEP005). Topical PEP005 treatment induces primary necrosis of tumor cells, potently activates protein kinase C, and was associated with an acute T cell-independent inflammatory response characterized by a pronounced neutrophil infiltrate. In Foxn1(nu) mice depleted of neutrophils and in CD18-deficient mice (in which neutrophil extravasation is severely impaired) PEP005 treatment was associated with a >70% increase in tumor relapse rates. NK cell or monocyte/macrophage deficiency had no effect on relapse rates. Both in vitro and in mice, PEP005 induced MIP-2/IL-8, TNF-alpha, and IL-1beta, all mediators of neutrophil recruitment and activation. In vitro, PEP005 activated human endothelial cells resulting in neutrophil adhesion and also induced human neutrophils to generate tumoricidal-reactive oxygen intermediates. Treatment of tumors with PEP005 significantly elevated the level of anticancer Abs, which were able to promote neutrophil-mediated Ab-dependent cellular cytotoxicity (ADCC) in vitro. PEP005 treatment of tumors grown in SCID mice was also associated with >70% increase in tumor relapse rates. Taken together, these data suggest a central role for neutrophil-mediated ADCC in preventing relapse. PEP005-mediated cure of tumors therefore appears to involve initial chemoablation followed by a neutrophil-dependent ADCC-mediated eradication of residual disease, illustrating that neutrophils can be induced to mediate important anticancer activity with specific chemotherapeutic agents.

Administration, Topical↗

PubMed2006

Chemokine- and adhesion-dependent survival of neutrophils after transmigration through cytokine-stimulated endothelium.

We examined the fate of neutrophils following transmigration through an endothelial monolayer cultured on "Transwell" membrane filters. Treatment of human umbilical vein endothelial cells (HUVEC) with increasing doses of tumor necrosis factor-alpha increased the efficiency of transmigration and markedly reduced apoptosis among the transmigrated neutrophils in a dose-dependent manner. Apoptosis was also inhibited after transmigration of neutrophils through HUVEC stimulated with interleukin (IL)-1beta but not so effectively after chemotaxis through unstimulated HUVEC driven by IL-8 added below the filter. Inhibition of beta2-integrin binding after transmigration or coating the lower chamber with a nonadhesive polymer (polyhydroxyl-ethyl-methacrylate) abrogated neutrophil survival. Although integrin engagement during migration itself was not essential to inhibit apoptosis, activation of neutrophils through CXC chemokine receptors was necessary. Quite brief exposure to the HUVEC (30-120 min) was effective in reducing subsequent apoptosis, although if coincubation with the HUVEC were prolonged, neutrophil apoptosis was reduced further. Neutralization of granulocyte macrophage-colony stimulating factor inhibited this additional effect. Thus, a complex interplay between migration- and activation-dependent signals and adhesive interaction in tissue may combine to effectively prolong the survival of neutrophils recruited during inflammation.

Apoptosis↗

PubMed2006

Differential survival of leukocyte subsets mediated by synovial, bone marrow, and skin fibroblasts: site-specific versus activation-dependent survival of T cells and neutrophils.

OBJECTIVE: Synovial fibroblasts share a number of phenotype markers with fibroblasts derived from bone marrow. In this study we investigated the role of matched fibroblasts obtained from 3 different sources (bone marrow, synovium, and skin) to test the hypothesis that synovial fibroblasts share similarities with bone marrow-derived fibroblasts in terms of their ability to support survival of T cells and neutrophils. METHODS: Matched synovial, bone marrow, and skin fibroblasts were established from 8 different patients with rheumatoid arthritis who were undergoing knee or hip surgery. Resting or activated fibroblasts were cocultured with either CD4 T cells or neutrophils, and the degree of leukocyte survival, apoptosis, and proliferation were measured. RESULTS: Fibroblasts derived from all 3 sites supported increased survival of CD4 T cells, mediated principally by interferon-beta. However, synovial and bone marrow fibroblasts shared an enhanced site-specific ability to maintain CD4 T cell survival in the absence of proliferation, an effect that was independent of fibroblast activation or proliferation but required direct T cell-fibroblast cell contact. In contrast, fibroblast-mediated neutrophil survival was less efficient, being independent of the site of origin of the fibroblast but dependent on prior fibroblast activation, and mediated solely by soluble factors, principally granulocyte-macrophage colony-stimulating factor. CONCLUSION: These results suggest an important functional role for fibroblasts in the differential accumulation of leukocyte subsets in a variety of tissue microenvironments. The findings also provide a potential explanation for site-specific differences in the pattern of T cell and neutrophil accumulation observed in chronic inflammatory diseases.

Apoptosis↗

PubMed2006

Phototoxicity and fluorotoxicity combine to alter the behavior of neutrophils in fluorescence microscopy based flow adhesion assays.

The use of fluorescent probes that allow visualization of leukocyte-endothelial cell (EC) interactions has greatly informed our understanding of leukocyte recruitment. However, effects of these agents on the biological functions of leukocytes are poorly described, leading to concerns about the interpretation of such data. Here we used two flow-based neutrophil adhesion assays to compare the effects of phase contrast illumination (PCI) with high intensity illumination (HII) used for fluorescent microscopy, in the presence or absence of five commonly used fluorochromes. Isolated neutrophils were either (1) perfused across P-selectin to establish a population of rolling cells, which were subsequently activated with fMLP; or (2) perfused across EC activated with TNF-alpha. In the absence of fluorescent dyes, HII did not affect levels of leukocyte adhesion; however, subsequent neutrophil behavior was dramatically altered when compared with cells under PCI, for example, dramatically reducing their migration velocities. In the presence of fluorescent dyes, the effects of HII were exacerbated, although the precise nature of the biological effects of these probes was agent specific. Thus, for the first time, our experiments describe the effects of fluorescent microscopy on the separate stages of the neutrophil recruitment process and reveal a previously unsuspected effect of HII on neutrophil migration.

Cell Adhesion↗

PubMed2006

Effects of disturbed flow on endothelial cell function: Pathogenic implications of modified leukocyte recruitment.

Numerous studies have shown that intracellular signalling, transcription factor activation and gene expression in endothelial cells are modulated by the magnitude and patterns of shear stress to which they are exposed. Although these responses suggest that the haemodynamic environment will consequently modulate the ability of the endothelial cells to support leukocyte recruitment as part of an inflammatory response, direct evidence is quite sparse. It seems that disturbances of flow (such as local spatial or temporal variation or sudden cessation) are likely to be pathogenic co-factors, combined with mediators such as cytokines, oxidised lipids or hypoxia, in conditions such as atherosclerosis, post-surgical intimal hyperplasia and ischaemia/reperfusion injury. In fact there have been few experimental investigations of these scenarios that include measurement of leukocyte adhesion and migration. We recently demonstrated that the level of steady shear to which EC are exposed has a powerful effect on their ability to support cytokine-induced leukocyte adhesion and migration. However, more combined studies of flow and agonist-mediated responses, with functional readouts, appear necessary if we are to develop a better understanding of the mechanisms pre-disposing to vascular inflammatory responses and pathology.

Animals↗

PubMed2006

An in vitro model for analysing neutrophil migration into and away from the sub-endothelial space: Roles of flow and CD31.

To model the later stages of neutrophil migration into tissue, we developed an assay in which human umbilical vein endothelial cells (HUVEC) were cultured on porous filters, treated with the inflammatory cytokine tumour necrosis factor-alpha (TNF), and then incorporated in a flow chamber. Video-microscopic observations were made of neutrophils as they were perfused over the HUVEC. When 3 microm pore filters were used (as opposed to 0.4 microm pore filters), neutrophils could be observed to migrate not only through the endothelial monolayer but also through the filter within minutes. The proportion of adherent neutrophils migrating through the endothelial monolayer and velocity of migration underneath it, were similar on the different filters, and also when neutrophils were perfused over cultures in glass capillaries, or settled on HUVEC cultured in standard plastic dishes. However, neutrophils migrated through HUVEC/filter constructs more rapidly in the flow chamber than in a standard, static, Transwell system, even though the velocities of migration under HUVEC were similar when directly observed under flow or static conditions. A function-blocking antibody against CD31 did not alter movement through the endothelial monolayer or the filter in the new flow system, but did reduce the migration velocity of neutrophils underneath the HUVEC (by 24%). Thus, we have developed a method for following each stage of neutrophil migration, including exit from the sub-endothelial space, and shown how they may be modified by applied fluid shear stress and blockade of a regulatory adhesion molecule.

Cell Adhesion↗

PubMed2005

Identification of a phenotypically and functionally distinct population of long-lived neutrophils in a model of reverse endothelial migration.

Recent studies have demonstrated that neutrophils are not a homogenous population of cells. Here, we have identified a subset of human neutrophils with a distinct profile of cell-surface receptors [CD54(high), CXC chemokine receptor 1(low) (CXCR1(low))], which represent cells that have migrated through an endothelial monolayer and then re-emerged by reverse transmigration (RT). RT neutrophils, when in contact with endothelium, were rescued from apoptosis, demonstrate functional priming, and were rheologically distinct from neutrophils that had not undergone transendothelial migration. In vivo, 1-2% of peripheral blood neutrophils in patients with systemic inflammation exhibit a RT phenotype. A smaller population existed in healthy donors ( approximately 0.25%). RT neutrophils were distinct from naïve circulatory neutrophils (CD54(low), CXCR1(high)) and naïve cells after activation with formyl-Met-Leu-Phe (CD54(low), CXCR1(low)). It is important that the RT phenotype (CD54(high), CXCR1(low)) is also distinct from tissue-resident neutrophils (CD54(low), CXCR1(low)). Our results demonstrate that neutrophils can migrate in a retrograde direction across endothelial cells and suggest that a population of tissue-experienced neutrophils with a distinct phenotype and function are present in the peripheral circulation in humans in vivo.

Apoptosis↗

PubMed2005

Cellular pathology of atherosclerosis: smooth muscle cells promote adhesion of platelets to cocultured endothelial cells.

Although platelets do not ordinarily bind to endothelial cells (EC), pathological interactions between platelets and arterial EC may contribute to the propagation of atheroma. Previously, in an in vitro model of atherogenesis, where leukocyte adhesion to EC cocultured with smooth muscle cells was greatly enhanced, we also observed attachment of platelets to the EC layer. Developing this system to specifically model platelet adhesion, we show that EC cocultured with smooth muscle cells can bind platelets in a process that is dependent on EC activation by tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1. Recapitulating the model using EC alone, we found that a combination of TGF-beta1 and TNF-alpha promoted high levels of platelet adhesion compared with either agent used in isolation. Platelet adhesion was inhibited by antibodies against GPIb-IX-V or alpha(IIb)beta3 integrin, indicating that both receptors are required for stable adhesion. Platelet activation during interaction with the EC was also essential, as treatment with prostacyclin or theophylline abolished stable adhesion. Confocal microscopy of the surface of EC activated with TNF-alpha and TGF-beta1 revealed an extensive matrix of von Willebrand factor that was able to support the adhesion of flowing platelets at wall shear rates below 400 s(-1). Thus, we have demonstrated a novel route of EC activation which is relevant to the atherosclerotic microenvironment. EC activated in this manner would therefore be capable of recruiting platelets in the low-shear environments that commonly exist at points of atheroma formation.

Atherosclerosis↗

PubMed2005

Prolonged culture of endothelial cells and deposition of basement membrane modify the recruitment of neutrophils.

We tested whether endothelial cell conditioning during prolonged culture and deposition of basement membrane (BM) could modify neutrophil recruitment induced by the inflammatory cytokine, tumour necrosis factor-alpha (TNF). Confluent endothelial cells (EC) from human umbilical veins were cultured for 1 to 20 days and then stimulated with 1, 10 or 100 U/ml of TNF for 4 h. When isolated neutrophils were settled on EC stimulated with the lower doses of TNF, the levels of adhesion and the proportion of adherent cells that transmigrated increased markedly with time of culture. At 100 U/ml TNF, time of culture had little effect on recruitment, but the transmigrated neutrophils moved more slowly under the monolayer in longer-term cultures. The inhibitory effects of function-blocking antibodies against E-selectin and beta2-integrin, and studies in which neutrophils were perfused over short- or long-term cultures, suggested that increased adhesion and migration arose from increased efficiency of neutrophil activation by the EC. Prolonged culture was also associated with deposition of a distinct BM. When fresh EC were seeded on day 20 BM, transmigrated neutrophils moved more slowly under the EC than under control monolayers. Thus, EC change their pro-inflammatory phenotype during prolonged culture, and the deposited basement membrane influences neutrophil migration.

Basement Membrane↗

PubMed2005

Endothelial cells, fibroblasts and vasculitis.

One of the most important questions in vasculitis research is not why inflammation of blood vessels occurs but why it persists, often in a site-specific manner. In this review we illustrate how stromal cells, such as fibroblasts and pericytes, might play an important role in regulating the site at which vasculitis occurs. Smooth muscle cells and fibroblasts directly influence the behaviour of overlying vascular cells, amplifying the response of the endothelium to proinflammatory agents such as TNF-alpha and allowing enhanced and inappropriate leucocyte recruitment. An abnormal local vascular stromal environment can therefore influence local endothelial function and drive the persistence of local vascular inflammation. However, such local vascular inflammation can have distant effects on the systemic vascular system, leading to widespread endothelial cell dysfunction. Vascular endothelial dysfunction is common in a range of immune-mediated inflammatory diseases, is seen in multiple vascular beds, and is reversible following the induction of disease remission. The mechanisms that drive such systemic vascular endothelial dysfunction are unclear but factors such as TNF-alpha and CRP may play a role. Persistence of such widespread endothelial dysfunction in systemic vasculitis appears to have long-term consequences, leading to the acceleration of atherosclerosis and premature ischaemic heart disease. It may also underlie the accelerated atherosclerosis seen in other immune-mediated rheumatic diseases, such as rheumatoid arthritis.

Cell Communication↗

PubMed2005

A novel mechanism of neutrophil recruitment in a coculture model of the rheumatoid synovium.

OBJECTIVE: Rheumatoid arthritis (RA) is classically thought of as a Th1, T lymphocyte-driven disease of the adaptive immune system. However, cells of the innate immune system, including neutrophils, are prevalent within the diseased joint, and accumulate in large numbers. This study was undertaken to determine whether cells of the rheumatoid stromal microenvironment could establish an inflammatory environment in which endothelial cells are conditioned in a disease-specific manner to support neutrophil recruitment. METHODS: Human umbilical vein endothelial cells (ECs) and fibroblasts isolated from the synovium or skin of RA patients were established in coculture on opposite sides of porous transwell filters. After 24 hours of EC conditioning, the membranes were incorporated into a parallel-plate, flow-based adhesion assay and levels of neutrophil adhesion to ECs were measured. RESULTS: ECs cocultured with synovial, but not skin, fibroblasts could recruit neutrophils in a manner that was dependent on the number of fibroblasts. Antibody blockade of P-selectin or E-selectin reduced neutrophil adhesion, and an antibody against CD18 (the beta2 integrin) abolished adhesion. Blockade of CXCR2, but not CXCR1, also greatly inhibited neutrophil recruitment. Interleukin-6 (IL-6) was detectable in coculture supernatants, and both IL-6 and neutrophil adhesion were reduced in a dose-dependent manner by hydrocortisone added to cocultures. Antibody blockade of IL-6 also effectively abolished neutrophil adhesion. CONCLUSION: Synovial fibroblasts from the rheumatoid joint play an important role in regulating the recruitment of inflammatory leukocytes during active disease. This process may depend on a previously unsuspected route of IL-6-mediated crosstalk between fibroblasts and endothelial cells.

Antibodies, Blocking↗

PubMed2005

Lymphocyte traffic through sinusoidal endothelial cells is regulated by hepatocytes.

Crosstalk between hepatic sinusoidal ECs and closely juxtaposed hepatocytes via vascular endothelial growth factor is essential for the maintenance of sinusoidal endothelial growth and differentiation. We propose that paracrine interactions between endothelial cells and hepatocytes also may be responsible for the unique complement of adhesion receptors expressed on sinusoidal endothelium that regulate the recruitment of lymphocytes into the liver. To address this hypothesis, we developed an in vitro model of the hepatic sinusoid in which flowing lymphocytes could interact with hepatic endothelium conditioned by the presence of hepatocytes. Human hepatic sinusoidal endothelial cells cocultured with hepatocytes were activated so that they supported the adhesion of lymphocytes at levels equivalent to those seen on endothelium stimulated with the inflammatory cytokine tumour necrosis factor-beta. Lymphocyte adhesion was supported by intracellular adhesion molecule 1, vascular cell adhesion molecule 1, and E-selectin, with an additional contribution from the novel adhesion receptor VAP-1. In conclusion, we show that interactions between hepatocytes and endothelial cells amplify leukocyte recruitment through the sinusoids by regulating the expression and function of endothelial adhesion molecules. These paracrine interactions may be responsible for the induction of the adhesion molecules that support constitutive lymphocyte recruitment to the liver as well as contributing significantly to the patterns of leukocyte adhesion seen during episodes of hepatic inflammation.

Amine Oxidase (Copper-Containing)↗

PubMed2005

A stromal address code defined by fibroblasts.

To navigate into and within tissues, leukocytes require guidance cues that enable them to recognize which tissues to enter and which to avoid. Such cues are partly provided at the time of extravasation from blood by an endothelial address code on the luminal surface of the vascular endothelium. Here, we review the evidence that fibroblasts help define an additional stromal address code that directs leukocyte behaviour within tissues. We examine how this stromal code regulates site-specific leukocyte accumulation, differentiation and survival in a variety of physiological stromal niches, and how the aberrant expression of components of this code in the wrong tissue at the wrong time contributes to the persistence of chronic inflammatory diseases.

Dendritic Cells↗

PubMed2004

Transmigrated neutrophils down-regulate the expression of VCAM-1 on endothelial cells and inhibit the adhesion of flowing lymphocytes.

As the first leukocytes recruited during inflammation, neutrophils are ideally situated to regulate the subsequent recruitment of mononuclear leukocytes. Here, we found that human neutrophils recruited by endothelial cells (EC), which had been stimulated with tumor necrosis factor alpha for 4 h, inhibited the adhesion of flowing, mixed mononuclear cells or purified lymphocytes over the subsequent 20 h but did not affect the adhesion of a secondary bolus of neutrophils. The degree of inhibition of lymphocyte adhesion increased with the duration of neutrophil-EC contact and with the number of recruited neutrophils. Antibody-blocking studies showed that lymphocyte adhesion was mediated predominantly by vascular cell adhesion molecule-1 (VCAM-1). Recruited neutrophils reduced the EC expression of VCAM-1 but not intercellular adhesion molecule-1 (ICAM-1) or E-selectin in a manner that mirrored the time- and number-dependent reduction in lymphocyte adhesion. VCAM-1 was not shed into the culture supernatant, and a panel of protease inhibitors was unable to reverse its down-regulation, indicating that it was not proteolytically degraded by neutrophils. In EC that had been in contact with neutrophils, the mRNA message for VCAM-1 but not ICAM-1 was down-regulated, indicating that alterations in transcriptional activity were responsible for the reduction in VCAM-1. Thus, under some inflammatory milieu, neutrophils may delay the recruitment of mononuclear leukocytes by regulating the expression of EC adhesion receptors.

Cell Adhesion↗

PubMed2004

The local physicochemical environment conditions the proinflammatory response of endothelial cells and thus modulates leukocyte recruitment.

The locations at which vascular endothelial cells recruit leukocytes during physiological or pathological inflammatory responses are influenced by direct effects of local haemodynamics on leukocyte adhesion. However, the expression of genes by endothelial cells, and their ability to respond to inflammatory cytokines also depend on the flow forces to which they are exposed. In addition, cells of the underlying stroma can modify the phenotype and responsiveness of endothelial cells, and hence their ability to recruit leukocytes. Thus, endothelial cells are plastic in their responses, and we hypothesise that the pattern of recruitment of leukocytes to tissues is critically dependent on the variable modulation of the endothelium by the local physicochemical microenvironment.

Animals↗

PubMed2004

Methods for exposing multiple cultures of endothelial cells to different fluid shear stresses and to cytokines, for subsequent analysis of inflammatory function.

Endothelial cells are conditioned by physicochemical environmental factors, including shear stress applied by flowing blood. However, the effects of shear conditioning on the functional responses of endothelial cells, such as ability to recruit leukocytes, remain uncertain. Here we describe a system for culturing multiple samples of endothelial cells under flow for prolonged periods, either at different shear stresses, or exposed concurrently to different concentrations of cytokines, for instance, tumour necrosis factor-alpha (TNF). The endothelial cells were cultured in glass capillaries (microslides) that could be conveniently transferred to a flow-based adhesion assay, to test the ability of the cultures to support adhesion and migration of flowing leukocytes. Paired control, 'static' samples were exposed to the identical medium and culture geometry. We found that the type of tubing used in the culture flow circuit and its maintenance at 37 degrees C were critical design factors, which could influence the response to TNF of the static controls which were exposed to recirculated medium. Endothelial cells conditioned by culture under flow showed a reduction in response to TNF, as judged by ability to induce the capture and migration of neutrophils. We found that the higher the shear stress, the weaker the ability to recruit neutrophils. This sensitivity to shear stress was greater if the cells were allowed to stabilise under static conditions for 24 h, compared to cells exposed to flow immediately after seeding. The inhibition of neutrophil recruitment was similar for cultures exposed to steady flow or flow with a pulsatile element (flow oscillation approximately 20% about the mean). Thus, we have developed a versatile culture system which allows investigations of functional modifications of endothelial cells and demonstrates the potential sensitivity of inflammatory responses to the local fluid environment.

Cytokines↗

PubMed2003

CD31 regulates direction and rate of neutrophil migration over and under endothelial cells.

Mechanisms guiding migration of neutrophils through endothelium are poorly understood. We showed previously that CD31-CD31 binding acted as an 'accelerator' for neutrophils migrating on platelets, while neutrophil alpha(v)beta3-integrin acted as a sensor to align migration with the direction of imposed flow. Here, we perfused neutrophils over human umbilical vein endothelial cells (HUVEC) treated with tumour necrosis factor-alpha, and characterised the kinetics of migration over, through and underneath the HUVEC. Before penetrating the monolayer, activated neutrophils migrated relatively slowly over the surface (approximately 6 microm/min), preferentially in the direction of flow. Once transmigrated, neutrophils moved more rapidly (approximately 14 microm/min) without preferred direction. Treatment of HUVEC and/or neutrophils with function-blocking antibodies against CD31 reduced directionality but not velocity of migration on top of HUVEC, and reduced velocity of migration underneath the monolayer. If neutrophils were pre-activated with formyl peptide, they did not migrate through the HUVEC, but migrated with increased velocity and directionality on top. Under these circumstances, both velocity and directionality were reduced by blocking CD31. alpha(v)beta3-integrin did not regulate migration under any conditions. We conclude that CD31-CD31 bonds act as robust sensors which can guide neutrophil migration, and also modify its velocity. Thus mechanical and adhesive signals can regulate neutrophil migration driven by locally-acting chemotactic agents.

Cell Adhesion↗

PubMed2003

Exposure to fluid shear stress modulates the ability of endothelial cells to recruit neutrophils in response to tumor necrosis factor-alpha: a basis for local variations in vascular sensitivity to inflammation.

Vascular endothelial cells are able to sense changes in the forces acting on them and respond, for instance, by modifying expression of a range of genes. However, there is little information on how such responses are integrated to modify homeostatic functions. We hypothesized that different shear stresses experienced in different regions of the circulation might influence endothelial sensitivity to inflammatory stimuli. We cultured human endothelial cells in tubes and exposed them for varying periods to shear stresses ranging from those typically found in postcapillary venules to those in arteries. When tumor necrosis factor-alpha was included in the flow cultures, we found startling differential effects of shear stress on the ability of endothelial cells to induce adhesion and migration of flowing neutrophils. Compared with static cultures, endothelial cells cultured at low shear stress (0.3 Pa) captured similar numbers of neutrophils but failed to induce their transendothelial migration. After exposure of endothelial cells to high shear stress (1.0 or 2.0 Pa), capture of neutrophils was largely ablated. The modification in response was detectable after 4 hours of exposure to flow but was much greater after 24 hours. From analysis of gene expression, loss of capture or migration was attributable to reduction in tumor necrosis factor-induced expression of selectins or CXC-chemokines, respectively. Thus, conditioning of endothelial cells by different flow environments may underlie variations in susceptibility to inflammation between different tissues or parts of the vascular tree.

Blotting, Western↗