This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cockerill, G. W. Articles by Haskard, D. O. Search for Related Content PubMed PubMed Citation Articles by Cockerill, G. W. Articles by Haskard, D. O. Pubmed/NCBI databases Substance via MeSH Related Collections Animal models of human disease Pathophysiology

(Circulation. 2001;103:108.)
© 2001 American Heart Association, Inc.

Basic Science Reports

Elevation of Plasma High-Density Lipoprotein Concentration Reduces Interleukin-1–Induced Expression of E-Selectin in an In Vivo Model of Acute Inflammation

Gillian W. Cockerill, PhD; Tanya Y. Huehns, MD; Arjuna Weerasinghe, MD; Claire Stocker, PhD; Peter G. Lerch, MD; Norman E. Miller, MD, PhD; Dorian O. Haskard, MD, PhD

From the British Heart Foundation Cardiovascular Research Unit, National Heart and Lung Institute, Imperial College School of Medicine, Hammersmith Hospital Campus, London, UK (G.W.C., T.Y.H., A.W., C.S., D.O.H.); the ZLB Central Laboratory, Blood Transfusion Service SRC, Bern, Switzerland (P.G.L.); and the Department of Cardiovascular Biochemistry, St Bartholomew’s and the Royal School of Medicine and Dentistry, Queen Mary’s and Westfield College, London, UK (N.E.M.).

Correspondence to G.W. Cockerill, Department of Cardiovascular Biochemistry, St Bartholomew’s and the Royal London SMD, Queen Mary’s and Westfield College, Charterhouse Square, London EC1 M 6BQ, UK. E-mail g.w.cockerill{at}mds.qmw.ac.uk

	Abstract

Top Abstract Introduction Methods Results Discussion References

 
Background—Although there is strong evidence that plasma HDL levels correlate inversely with the incidence of coronary artery disease, the precise mechanism(s) for the protective effect of HDLs remains unclear. We recently showed that HDLs inhibit endothelial cell expression of cytokine-induced leukocyte adhesion molecules in vitro. Our study therefore sought to test the hypothesis that elevating the level of circulating HDLs would inhibit endothelial cell activation in vivo.

Methods and Results—We used a porcine model of inflammation previously established in our laboratory, in which the level of vascular endothelial cell expression of E-selectin in interleukin (IL)-1–induced skin lesions was measured by the uptake of a radiolabeled anti–E-selectin antibody (1.2B6). Porcine plasma HDL levels were elevated by use of a bolus injection of reconstituted discoidal HDL (recHDL). These particles resemble nascent HDL particles in shape and contain apolipoprotein A-I as the sole protein and soybean phosphatidylcholine as the sole phospholipid. We found that recHDLs inhibited the expression of IL-1–induced E-selectin by porcine aortic endothelial cells in vitro, confirming that the inhibitory effect is conserved with synthetic HDLs and demonstrating that the phenomenon is not restricted to human endothelial cells. In vivo, elevating the circulating level of HDLs 2-fold led to significant inhibition of basal and IL-1–induced E-selectin expression by porcine microvascular endothelial cells.

Conclusions—These observations demonstrate the potential anti-inflammatory action of HDLs and provide support for the further investigation of the mechanisms underlying the inhibitory effects of HDLs on endothelial cell activation.

Key Words: inflammation • atherosclerosis • proteins • endothelium • apolipoproteins

	Introduction

Top Abstract Introduction Methods Results Discussion References

 
The negative association of plasma HDL concentration with coronary artery disease has been well documented in epidemiological studies.^{1 2 3} Although experiments in animals have demonstrated an antiatherogenic activity of HDLs,^{4 5 6 7 8} it is not yet known whether this protective effect is related to the role of the lipoprotein in reverse cholesterol transport or to a different mechanism.^{9 10 11 12 13 14 15 16 17 18} Of the many components of plasma HDLs, apolipoprotein (apo) A-I appears to be critical for at least a proportion of its antiatherogenic activity.

There is now considerable support for the importance of leukocyte recruitment into the arterial intima, both for the development of atheroma and for the maintenance of the mature plaque. Indeed, the earliest observable cellular event in the genesis of atheroma is the binding of leukocytes to the endothelium.^{19 20} Also, several studies have now demonstrated the presence of cytokine-induced adhesion molecules for leukocytes (eg, E-selectin, intercellular adhesion molecule [ICAM]-1, and vascular cell adhesion molecule [VCAM]-1), both in animal models of atherosclerosis^{21 22} and in human atherosclerotic tissue.^{23 24 25} In previous studies, we have explored the possibility that the protective effect of HDLs may be related to an ability to inhibit cytokine-induced endothelial cell adhesion molecule expression. HDLs were found to inhibit the upregulation of E-selectin, VCAM-1, and ICAM-1 by interleukin (IL)-1ß or tumor necrosis factor- in cultured human umbilical vein endothelial cells at the level of both steady-state mRNA and surface protein expression.^{26 27} In the present study, we used a radiolabeled monoclonal antibody targeting technique in the pig, developed in our laboratory,^{28 29 30} to show that inhibition of E-selectin expression by HDLs also occurs in vivo.

	Methods

Top Abstract Introduction Methods Results Discussion References

 
Reagents
Recombinant human IL-1 (2x10⁷ U/mg) was a kind gift from Glaxo Wellcome (Geneva, Switzerland). Reconstituted HDLs (recHDLs) were prepared from plasma-derived human apoA-I and soybean phosphatidylcholine by cholate dialysis in the ZLB Central Laboratory,^{31 32} resulting in the generation of discoidal particles with an average protein:phospholipid molar ratio of 1:150. The physical properties of these proteoliposomes have been described previously in detail.³²

Isolation and Growth of Porcine Aortic Endothelial Cells
Porcine aortic endothelial cells (PAECs) were isolated and grown according to the modified method of Jaffe et al^{33 34} from aortas obtained from the local abattoir and transported in Hanks’ balanced salt solution (GIBCO) containing 50 U/mL penicillin, 50 µg/mL streptomycin, 100 µg/mL gentamicin, 1 mmol/L sodium pyruvate, and 0.1 µg/mL amphotericin (all from GIBCO). After removal of loose connective tissue and ligation of branching vessels, the aortas were filled with collagenase A (0.25 mg/mL, Boehringer Mannheim) for 15 minutes at 37°C. Endothelial cells were harvested and seeded into 25-cm² flasks (Costar) precoated with 1% gelatin (Sigma) in RPMI 1640 (GIBCO) supplemented with 20% heat-inactivated FCS (GIBCO), antibiotics (as above), 15 U/mL sodium heparin, 10 mmol/L l-glutamine, and 10 µg/mL endothelial cell growth supplement (Sigma). Cells were used for experiments before the fourth passage.

Animals
The animals used in this study were healthy Large White pigs weighing 15 to 20 kg derived from lines of stock lacking the halothane-sensitivity gene. Animals were obtained from a commercial supplier and housed under standard husbandry conditions. Animals were studied according to a protocol approved under the UK Animals (Scientific Procedures) Act, 1986.

Monoclonal Antibodies
1.2B6 is a mouse IgG1 monoclonal antibody (mAb) that recognizes human E-selectin³⁵ and P-selectin.³⁶ This antibody also recognizes porcine E-selectin but not porcine P-selectin, as shown by reactivity with COS-7 cells transfected with porcine E-selectin or P-selectin cDNA.³⁷ MOPC21 is a nonbinding mouse IgG1 myeloma protein and was kindly supplied by Dr M. Robinson (Celltech Ltd, Slough, Berkshire, UK). Antibodies were radiolabeled with ¹¹¹In and ^99mTc as previously described.³⁸

Apo A-I Assay
ApoA-I was determined immunoturbidimetrically on a Cobas-Fara centrifugal analyzer (Roche Diagnostic). The apoA-I antibody and standards were obtained from Boehringer Mannheim. The human apoA-I antibody did not cross-react with porcine apoA-I.

Model of Cutaneous Inflammation
Animals were anesthetized for the bolus injections of recHDL and intradermal injections of IL-1. Anesthesia was induced initially with halothane by inhalation, resulting in rapid induction of sedation with minimal stress. Anesthesia was maintained by repeated intravenous boluses of propofol (1 mg/kg; Diprivan, Zeneca Pharmaceuticals) given every 15 to 20 minutes. The animals did not require intubation or other external support. Cutaneous inflammatory sites were induced by intradermal injections of IL-1 or saline control, as previously described.^{28 29} For the dose-response experiments, the animals were lightly sedated for the entire time (3 hours), after which ¹¹¹In-labeled 1.2B6 and ^99mTc-labeled MOPC21 were injected as a bolus via an ear vein and allowed to circulate for 5 minutes. Animals were then exsanguinated under deep anesthesia, after which standard skin disks 20 mm in diameter were excised and weighed. Radioactivity of the excised tissue was measured in a gamma-counter (Minaxi 5530, Canberra-Packard). Radioactivity in cpm/g for each sample was adjusted for decay and spillover from the ¹¹¹In channel into the ^99mTc channel. Specific anti–E-selectin mAb uptake in skin disks, which is a measure of luminal endothelial E-selectin expression, was calculated by subtracting the percentage of injected ^99mTc per gram disk tissue from the percentage of injected ¹¹¹In per gram disk tissue. During the time-course experiments, animals were allowed to return to their holding pens after the IL-1 skin spots had been administered under mild sedation.

Statistical Analysis
Data comparing the dose response to HDLs in vitro (Figure 1) were analyzed by 1-factor ANOVA followed by Dunnett’s test for multiple comparisons. The in vivo dose-response data (Figure 2) and time-course data (Figure 3) were compared by 2-factor ANOVA.

View larger version (19K): [in this window] [in a new window]   Figure 1. RecHDLs inhibit IL-1–induced expression of E-selectin by PAECs. Concentration-dependent effect of recHDLs on IL-1–induced expression of E-selectin by PAECs. Confluent monolayers of endothelial cells were incubated in presence of a range of recHDLs for 3 hours. IL-1 (10 ng/mL) was then added to culture medium. Cell-surface expression of E-selectin was measured by flow cytometry 4 hours later. Values represent mean fluorescence intensities of E-selectin in response to IL (open bars) relative to unstimulated basal expression (solid bars). Values are mean±SD, n=6. Statistical analysis using 1-factor ANOVA, followed by Dunnett’s t test, P<0.01. Data are representative of 3 similar experiments.

View larger version (21K): [in this window] [in a new window]   Figure 2. Effect of recHDLs on expression of E-selectin in response to different concentrations of IL-1. One pig received a bolus injection of recHDL (50 mg/kg) (), and a control animal received a similar volume of PBS (). Fifteen minutes later, animals were injected in multiple sites intradermally with various amounts of IL-1 in 50 µL of PBS per site. Animals were kept under light sedation for 3 hours before intravenous injection of 111In-labeled E-selectin (mAb 1.2B6) and 99mTc-labeled isotype-matched irrelevant antibody (MOPC21). Five minutes later, pigs were exsanguinated and skin disks excised and counted. Percent specific anti–E-selectin uptake was calculated as percent injected dose of E-selectin antibody localized in lesion minus percent injected dose of irrelevant control antibody. Data points are mean±SD, n=7, and are representative of 2 similar experiments (4 animals). Statistical analysis using 2-factor ANOVA, interaction P<0.05.

View larger version (20K): [in this window] [in a new window]   Figure 3. Effect of recHDL on time-dependent IL-1–induced expression of E-selectin in porcine skin spots. Pigs were pretreated with either intravenous recHDL (50 mg/kg) (•) or a similar volume of PBS () and then injected intradermally with IL-1 at 2, 3.5, and 5.5 hours before injection of 111In-labeled E-selectin (mAb 1.2B6) and 99mTc-labeled isotype-matched irrelevant antibody (MOPC21). A third pig received intravenous recHDL (50 mg/kg) 5 minutes before injection of radiolabeled antibodies (). Data points are mean±SD, n=7, and are representative of 3 similar experiments (9 animals). Statistical analysis using 2-factor ANOVA, interaction P<0.05.

	Results

Top Abstract Introduction Methods Results Discussion References

 
Reconstituted HDLs Inhibit Cytokine-Induced Activation of PAECs In Vitro
Before the proposed in vivo study, we needed to establish that recHDL could inhibit cytokine-induced expression of E-selectin on PAECs in vitro. When confluent monolayers of PAECs were preincubated for 3 hours with a range of concentrations of recHDL before being stimulated for 4 hours with IL-1 (10 ng/mL), the level of expression of E-selectin, measured by flow cytometry, was found to be reduced in a dose-dependent fashion (Figure 1). Maximal inhibition of 71.6±8.7% (mean±SD, P<0.01) was observed after pretreatment with recHDLs at 1 mg/mL apoA-I, compared with similar cytokine-treated cell cultures that had not been preincubated with recHDL (Figure 1).

In Vivo Clearance of Reconstituted HDL
To establish the kinetics of clearance of intravenously injected recHDL in the pig, we measured changes in the plasma concentration of human apoA-I. We found that the concentration of apoA-I had decreased by 30% of the initial level after 6 hours (Table).

View this table: [in this window] [in a new window]   Table 1. Concentration of Human Apo A-I in Pig Plasma After a Bolus Injection of recHDLs (50 mg/kg)

Effect of recHDL on Basal and IL-1–Dependent E-Selectin Expression
For our study of the effect of recHDL on expression of E-selectin in vivo, 1 pig received a bolus injection of recHDL (50 mg/kg), and a control animal received a similar volume of PBS. Fifteen minutes later, the animals were injected in multiple sites intradermally with various amounts of IL-1 in 50 µL PBS per site. It is known that unstimulated microvascular endothelium in pig skin expresses readily detectable E-selectin,^{28 29 30} and this was significantly reduced in pigs treated with recHDL, as measured by the specific uptake of intravenously injected anti–E-selectin mAb 1.2B6 after 3 hours (Figure 2). Furthermore, recHDL abrogated the upregulation of E-selectin in response to concentrations of IL-1 up to 100 ng/site.

Another experiment was conducted to exclude the possibility that the apparent inhibition of E-selectin expression by recHDL was due to interference of the binding of mAb 1.2B6 to E-selectin. Pigs were pretreated intravenously with either recHDL (50 mg/kg) or a similar volume of PBS and then were given intradermal injections of IL-1 at 1.5, 3.5, and 5.5 hours before injection of radiolabeled antibodies. During the skin spot injections, the animals recovered from sedation and were returned to holding pens. A third pig received intravenous recHDL (50 mg/kg) 5 minutes before injection of radiolabeled antibodies. As shown in Figure 3, no inhibition of E-selectin expression was seen in animals that received recHDL immediately before the injection of radiolabeled antibodies, indicating that recHDL did not influence the measurement of E-selectin expression with this technique. The relative distribution of both the nonspecific and the E-selectin antibodies in heart, kidney, liver, spleen, lung, and gut did not differ significantly between experiments.

	Discussion

Top Abstract Introduction Methods Results Discussion References

 
Since the initial report that HDLs could inhibit cytokine-induced expression of endothelial cell adhesion molecules,²⁶ further in vitro work has supported the observation by showing that HDLs containing the apoA-I_Milano, a naturally occurring mutant form, has similar activity³⁹ and that reconstituted HDL particles containing either apoA-I or apoA-II as the sole protein can prevent cytokine-induced VCAM-1 expression.⁴⁰ Nevertheless, there has been a need to demonstrate that HDLs can inhibit endothelial cell adhesion molecule expression in vivo. In this study we have shown, using a sensitive radiolabeled antibody targeting assay, that HDLs suppress microvascular E-selectin expression in pigs.

The only physiological way of quickly elevating the plasma HDL concentration is to give a bolus injection of discoidal apoA-I/lecithin proteoliposomes, which effectively mimics an increase in nascent HDL secretion rate by the liver.⁴¹ The use of phospholipid liposomes as a control would have been valid only if this had had no effect on the number and types of HDLs in plasma. However, we know that this would not have been the case. Under the influence of plasma phospholipid transfer protein,^{42 43} some of the infused phospholipid would have been rapidly incorporated into existing HDLs.^{44 45 46} Addition of phospholipid to HDLs has been shown to destabilize the particles, leading to fusion of particles and release of apoA-I, which subsequently associates with other liposomes to produce apoA-I/phospholipid disks.^{47 48 49} Thus, the use of phospholipid liposomes as a control would not merely have increased the plasma phospholipid concentration but would also have had major effects on the number of HDLs, including the production of discoidal particles similar to those used in the test animals. The use of lipid-free apoA-I alone would also have been an unsuitable control, because this is very rapidly cleared in the plasma.⁵⁰

Because the original in vitro data were obtained in human endothelial cells of umbilical origin, it was important to establish that HDLs were capable of inhibiting cytokine-induced adhesion molecule expression by porcine endothelial cells before embarking on an in vivo study. We found that PAECs isolated from 50- to 60-kg animals and used at early passage were able to support a high level of expression of E-selectin on stimulation with IL-1, as previously reported.³⁷ The ability of HDLs to ablate this induction was established by preincubation of cell cultures with a physiologically relevant concentration of recHDLs.

Our results clearly indicate that recHDLs are able to reduce expression of E-selectin in vivo, both basally and in response to IL-1. The possibility that recHDLs hindered the radiolabeled anti–E-selectin antibody from binding to its endothelial antigen was excluded by an experiment showing that recHDLs administered immediately before injection of radiolabeled antibodies had no inhibitory effect. This study therefore provides the first direct evidence that HDLs inhibit endothelial cell activation and adhesion molecule expression. Although HDL has been found to inhibit E-selectin gene transcription, the precise mechanism for this is still unknown. Because HDLs do not inhibit IB degradation or the nuclear translocation of nuclear factor-B, the mechanism must involve a process independent of this ubiquitous family of transactivating factors.²⁷

In summary, we have shown for the first time that elevation of the circulating level of HDLs, in a genetically normal large mammal, can inhibit cytokine adhesion molecule expression in vivo. Our data support the anti-inflammatory function of HDLs as a potential mechanism for the recent demonstration that recA-I_Milano particles reduce macrophage infiltration in lesions in apoE-null mice,⁵¹ a mechanism further supported by the recent demonstration that recHDLs were also able to inhibit neointimal thickening and VCAM-1 expression in the same mouse model.⁵²

From consideration of data showing that HDLs are able to mediate differential gene expression and activate signal transduction pathways, leading to Ras activation, we hypothesize that HDLs may act through modulation of cAMP-responsive elements. We have found that HDLs modulate cAMP response element binding protein retardation complexes in endothelial cells (unpublished observation). These observations provide the basis of our future work, which may provide an explanation as to how HDLs mediate their anti-inflammatory actions. Establishing the precise mechanism of action of HDLs will be crucial if raising levels is to be considered therapeutically advantageous.

	Acknowledgments

 
This study was supported by the British Heart Foundation (BHF). Dr Cockerill holds an Intermediate Fellowship Award, Drs Miller and Haskard are both BHF Professors, and Dr Weerasinghe holds a BHF Clinical Research Fellowship. Dr Huehns was funded by the Garfield Weston Trust.

Received May 9, 2000; revision received July 12, 2000; accepted July 18, 2000.

	References

Top Abstract Introduction Methods Results Discussion References

 

1. 1. Miller GJ, Miller NE. Plasma high-density lipoprotein concentration and development of ischaemic heart-disease. Lancet. 1975;1:16–19.[Medline] [Order article via Infotrieve]
   
2. Yaari S, Goldbourt U, Even-Zohar S, et al. HDL and total cholesterol: association with total, cardiovascular and cancer mortality in a seven year prospective study of 10,000 men. Lancet. 1981;1:1011–1015.[Medline] [Order article via Infotrieve]
   
3. Gordon DJ, Probsfield JL, Garrison RJ, et al. High-density lipoprotein cholesterol and cardiovascular disease: four prospective American studies. Circulation. 1989;79:8–15.[Abstract/Free Full Text]
   
4. Rubin EM, Krauss RM, Spangler EA, et al. Inhibition of early atherogenesis in transgenic mice by human apolipoprotein AI. Nature. 1991;353:265–267.[Medline] [Order article via Infotrieve]
   
5. Plump AS, Scott CJ, Breslow JL. Human apolipoprotein A-I gene expression in the apolipoprotein E-deficient mouse. Proc Natl Acad Sci U S A. 1994;91:9607–9616.[Abstract/Free Full Text]
   
6. Paszty C, Maeda N, Verstuyft J, et al. Apolipoprotein AI transgene corrects apolipoprotein E-deficiency-induced atherosclerosis in mice. J Clin Invest. 1998;94:899–903.
   
7. Badimon JJ, Badimon L, Fuster V. Regression of atherosclerotic lesions by high-density lipoprotein plasma fraction in cholesterol fed rabbits. J Clin Invest. 1990;85:1234–1241.
   
8. Ameli S, Hultgardh-Nilsson A, Cerek B, et al. Recombinant apolipoprotein A-I Milano reduces intimal thickening after balloon injury in hypercholesterolemic rabbits. Circulation. 1994;90:1935–1941.[Abstract/Free Full Text]
   
9. Glomset JA. The plasma lecithin:cholesterol acyltransferase reaction. J Lipid Res. 1968;9:155–167.[Abstract]
   
10. Johnson WJ, Mahlberg FH, Rothblat GH, et al. Cholesterol transport between cells and high-density lipoproteins. Biochim Biophys Acta. 1991;1085:273–298.[Medline] [Order article via Infotrieve]
    
11. Parthasarathy S, Barnett J, Fong LG. High-density lipoprotein inhibits the oxidative modification of low-density lipoprotein. Biochim Biophys Acta. 1990;1044:275–283.[Medline] [Order article via Infotrieve]
    
12. Cockerill GW, Reed S. High-density lipoprotein-multipotent effects on cells of the vasculature. Int Rev Cytol.. 1999;188:257–297.[Medline] [Order article via Infotrieve]
    
13. Mackness MI, Abbot C, Arrol S, et al. The role of high-density lipoprotein and lipid-soluble antioxidant vitamins in inhibiting low-density lipoprotein oxidation. Biochem J. 1993;294:829–834.
    
14. Navab M, Imes SS, Hama SY, et al. Monocyte transmigration induced by modification of low density lipoprotein in co-culture of human aortic wall cells is due to induction of monocyte chemotactic protein 1 and is abolished by high density lipoprotein. J Clin Invest. 1991;88:2039–2046.
    
15. Watson AD, Berliner JA, Hama SY, et al. Protective effect of high density lipoprotein associated paraoxonase: inhibition of the biological activity of minimally oxidised low density lipoprotein. J Clin Invest. 1995;96:2882–2891.
    
16. Tauber J-P, Cheng J, Gospodarowicz D. Effect of high and low density lipoproteins on proliferation of cultured bovine vascular endothelial cells. J Clin Invest. 1980;66:696–708.
    
17. Levine DM, Parker TS, Donnely TM, et al. In vivo protection against endotoxin by high density lipoprotein. Proc Natl Acad Sci U S A. 1993;90:12040–12044.[Abstract/Free Full Text]
    
18. Pajkrt D, Doran JE, Koster F, et al. Antiinflammatory effects of reconstituted high-density lipoprotein during human endotoxemia. J Exp Med. 1996;184:1601–1608.[Abstract/Free Full Text]
    
19. Gerrity RG, Naito HK, Richardson M, et al. Dietary induced atherogenesis in swine: morphology of the intima in pre-lesion stages. Am J Pathol. 1979;95:775–792.[Medline] [Order article via Infotrieve]
    
20. Davies MJ, Woolf N, Rowles PM, et al. Morphology of the endothelium over atherosclerotic plaques in human coronary arteries. Br Heart J. 1988;60:459–464.[Abstract/Free Full Text]
    
21. Nakashima Y, Raines EW, Plump AS, et al. Upregulation of VCAM-1 and ICAM-1 at atherosclerosis-prone sites on the endothelium in the apoE-deficient mouse. Arterioscler Thromb Vasc Biol. 1998;18:842–851.[Abstract/Free Full Text]
    
22. Iiyama K, Hajra L, Iiyama M, et al. Patterns of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 expression in rabbit and mouse atherosclerotic lesions and at sites predisposed to lesion formation. Circ Res. 1999;85:199–207.[Abstract/Free Full Text]
    
23. Poston RN, Haskard DO, Goucher JR, et al. Expression of intercellular adhesion molecule-1 in atherosclerotic plaques. Am J Pathol. 1992;140:665–673.[Abstract]
    
24. Van de Wal AC, Das PK, Tigges AJ, et al. Adhesion molecules on the endothelium and mononuclear cells in human atherosclerotic lesions. Am J Pathol. 1992;141:161–168.[Abstract]
    
25. Wood KM, Cadogan MD, Ranshaw AL, et al. The distribution of adhesion molecules in human atherosclerosis. Histopathology. 1993;22:437–444.[Medline] [Order article via Infotrieve]
    
26. Cockerill GW, Rye K-A, Gamble JR, et al. High density lipoproteins inhibit cytokine-induced expression of endothelial cell adhesion molecules. Arterioscler Thromb Vasc Biol. 1995;15:1987–1994.[Abstract/Free Full Text]
    
27. Cockerill GW, Saklatvala J, Ridley SH, et al. High-density lipoproteins differentially modulate cytokine-induced expression of E-selectin and cyclooxygenase-2. Arterioscler Thromb Vasc Biol. 1999;19:910–917.[Abstract/Free Full Text]
    
28. Keelan ETM, Licence ST, Peters AM, et al. Characterization of E-selectin expression in vivo with use of a radiolabelled monoclonal antibody. Am J Physiol. 1994;166:H279–H290.
    
29. Binns RM, Licence ST, Harrison AA, et al. In vivo E-selectin upregulation correlates early with migration of PMN, later with PBL entry: Mabs block both. Am J Physiol. 1996;270:H183–H193.[Abstract/Free Full Text]
    
30. Binns RM, Whyte A, Licence ST, et al. The role of E-selectin in lymphocyte and polymorphonuclear cell recruitment into cutaneous delayed hypersensitivity reactions in sensitised pigs. J Immunol. 1996;157:4094–4099.[Abstract]
    
31. Lerch PG, Morgenthaler J-J, Peitsch MC, et al. Isolation and properties of apolipoprotein A for therapeutic use. In: Poulik MD, ed. Protides of the Biological Fluids. Proceedings of the 36th Colloquium. Vol 36. Lipoproteins, IgG and IgA Subclasses, Cytofluorometry. Oxford, England: Pergamon Press; 1989:409–416.
    
32. Lerch PG, Fortsch V, Hodler G, et al. Production and characterization of a reconstituted high-density lipoprotein for therapeutic applications. Vox Sang. 1996;71:155–164.[Medline] [Order article via Infotrieve]
    
33. Jaffe EA, Nachman RL, Becker CG, et al. Culture of human endothelial cells derived from umbilical veins: identification by morphologic and immunologic criteria. J Clin Invest. 1973;52:2745–2756.
    
34. Slater DN, Sloan JM. The porcine endothelial cell in tissue culture. Atherosclerosis. 1975;21:259–272.[Medline] [Order article via Infotrieve]
    
35. Wellicome SM, Thronhill MH, Pitzalis C, et al. A monoclonal antibody that detects a novel antigen on endothelial cells that is induced by tumor necrosis factor, IL1 or lipopolysaccharides. J Immunol. 1990;144:2558–2565.[Abstract]
    
36. Goda K, Tanaka T, Monden M, et al. Characterization of an apparently conserved epitope in E- and P-selectin identified by dual-specific monoclonal antibodies. Eur J Immunol. 1999;29:1551–1560.[Medline] [Order article via Infotrieve]
    
37. Tsang YT, Stephens PE, Licence ST, et al. Porcine E-selectin: cloning and functional characteristics. Immunology. 1995;85:140–145.[Medline] [Order article via Infotrieve]
    
38. Jamar F, Chapman PT, Harrison AA, et al. Imaging endothelial cell activation in inflammatory arthritis using an In-111 labeled anti-E-selectin monoclonal F(ab')₂. Radiology. 1995;194:843–850.[Abstract/Free Full Text]
    
39. Calebresi L, Franceschini G, Sirtori CR, et al. Inhibition of VCAM-1 expression in endothelial cells by reconstituted high density lipoproteins. Biochem Biophys Res Commun. 1997;238:61–65.[Medline] [Order article via Infotrieve]
    
40. Ashby DT, Rye KA, Clay MA, et al. Factors influencing the ability of HDL to inhibit expression of vascular cell adhesion molecule-1 in endothelial cells. Arterioscler Thromb Vasc Biol. 1998;8:1450–1455.
    
41. Nanjee MN, Doran JE, Lerch PG, et al. Acute effects of intravenous infusion of apoA-I/phosphatidylcholine discs on plasma lipoproteins in humans. Arterioscler Thromb Vasc Biol. 1999;19:979–989.[Abstract/Free Full Text]
    
42. Lagrost L, Desrumaux C, Masson D, et al. Structure and function of the plasma phospholipid transfer protein. Curr Opin Lipidol. 1998;9:203–209.[Medline] [Order article via Infotrieve]
    
43. Tu A-Y, Nishida HI, Nishida T. High density lipoprotein conversion mediated by human plasma phospholipid transfer protein. J Biol Chem. 1993;268:23098–23105.[Abstract/Free Full Text]
    
44. Martins IJ, Lenzo NP, Redgrave TG. Phosphatidylcholine metabolism after transfer from lipid emulsions injected intravenously in rats: implications for high-density lipoprotein metabolism. Biochim Biophys Acta. 1989;1005:217–224.[Medline] [Order article via Infotrieve]
    
45. Zierenberg O, Odenthal J, Betzing H. Microporation of polyenephosphatidylcholine into serum lipoproteins after oral or intravenous administration. Atherosclerosis. 1979;34:259–276.[Medline] [Order article via Infotrieve]
    
46. Taskinen MR, Nikkila EA, Tulikoura I. Changes of high density lipoprotein subfraction concentration and composition by intralipid in vivo and by lipolysis of intralipid in vitro. Arteriosclerosis. 1983;3:607–615.[Abstract/Free Full Text]
    
47. Forte TM, Ren CL, Nordhausen RW, et al. Formation of phospholipid-rich HDL: a model for square-packing lipoprotein particles found in interstitial fluid and in abetalipoproteinemic plasma. Biochim Biophys Acta. 1985;834:386–395.[Medline] [Order article via Infotrieve]
    
48. Tall AR, Small DM. Solubilisation of phospholipid membranes by human plasma high density lipoproteins. Nature. 1977;265:163–164.[Medline] [Order article via Infotrieve]
    
49. Nichols AV, Gong EL, Forte TM, et al. Interaction of plasma high density lipoprotein HDL_2b (d 1.063–1.100 g/ml) with single-bilayer liposomes of dimyristoylphosphatidylcholine. Lipids. 1978;13:943–950.[Medline] [Order article via Infotrieve]
    
50. Nanjee MN, Crouse JR, King JM, et al. Effects of intravenous infusion of lipid-free apo A-I in humans. Arterioscler Thromb Vasc Biol. 1996;16:1203–1214.[Abstract/Free Full Text]
    
51. Shah PK, Nilsson J, Kaul S, et al. Effects of recombinant apolipoprotein A-I_Milano on aortic atherosclerosis in apolipoprotein E–deficient mice. Circulation. 1998;97:780–785.[Abstract/Free Full Text]
    
52. Dimayuga P, Zhu J, Oguchi S, et al. Reconstituted HDL containing human apolipoprotein A-I reduces VCAM-1 expression and neointima formation following periadventitial cuff-induced carotid injury in apo E null mice. Biochem Biophys Res Commun. 1999;264:465–468.[Medline] [Order article via Infotrieve]
    

This article has been cited by other articles:

				M. Tolle, A. Pawlak, M. Schuchardt, A. Kawamura, U. J. Tietge, S. Lorkowski, P. Keul, G. Assmann, J. Chun, B. Levkau, et al. HDL-Associated Lysosphingolipids Inhibit NAD(P)H Oxidase-Dependent Monocyte Chemoattractant Protein-1 Production Arterioscler. Thromb. Vasc. Biol., August 1, 2008; 28(8): 1542 - 1548. [Abstract] [Full Text] [PDF]

				A. Singh-Manoux, D. Gimeno, M. Kivimaki, E. Brunner, and M. G. Marmot Low HDL Cholesterol Is a Risk Factor for Deficit and Decline in Memory in Midlife: The Whitehall II Study Arterioscler. Thromb. Vasc. Biol., August 1, 2008; 28(8): 1556 - 1562. [Abstract] [Full Text] [PDF]

				E. M. deGoma, R. L. deGoma, and D. J. Rader Beyond high-density lipoprotein cholesterol levels evaluating high-density lipoprotein function as influenced by novel therapeutic approaches. J. Am. Coll. Cardiol., June 10, 2008; 51(23): 2199 - 2211. [Abstract] [Full Text] [PDF]

				S. J. Robins, D. Collins, J. J. Nelson, H. E. Bloomfield, and B. F. Asztalos Cardiovascular Events With Increased Lipoprotein-Associated Phospholipase A2 and Low High-Density Lipoprotein-Cholesterol: The Veterans Affairs HDL Intervention Trial Arterioscler. Thromb. Vasc. Biol., June 1, 2008; 28(6): 1172 - 1178. [Abstract] [Full Text] [PDF]

				S. Van Linthout, F. Spillmann, A. Riad, C. Trimpert, J. Lievens, M. Meloni, F. Escher, E. Filenberg, O. Demir, J. Li, et al. Human Apolipoprotein A-I Gene Transfer Reduces the Development of Experimental Diabetic Cardiomyopathy Circulation, March 25, 2008; 117(12): 1563 - 1573. [Abstract] [Full Text] [PDF]

				U. Lim, T. Gayles, H. A. Katki, R. Stolzenberg-Solomon, S. J. Weinstein, P. Pietinen, P. R. Taylor, J. Virtamo, and D. Albanes Serum High-Density Lipoprotein Cholesterol and Risk of Non-Hodgkin Lymphoma Cancer Res., June 1, 2007; 67(11): 5569 - 5574. [Abstract] [Full Text] [PDF]

				N. Scarmeas Invited Commentary: Lipoproteins and Dementia--Is It the Apolipoprotein A-I? Am. J. Epidemiol., May 1, 2007; 165(9): 993 - 997. [Abstract] [Full Text] [PDF]

				P. Barter Options for therapeutic intervention: how effective are the different agents? Eur. Heart J. Suppl., October 1, 2006; 8(suppl_F): F47 - F53. [Abstract] [Full Text] [PDF]

				A. Kontush and M. J. Chapman Functionally Defective High-Density Lipoprotein: A New Therapeutic Target at the Crossroads of Dyslipidemia, Inflammation, and Atherosclerosis Pharmacol. Rev., September 1, 2006; 58(3): 342 - 374. [Abstract] [Full Text] [PDF]

				P. Barter The role of HDL-cholesterol in preventing atherosclerotic disease Eur. Heart J. Suppl., July 1, 2005; 7(suppl_F): F4 - F8. [Abstract] [Full Text] [PDF]

				S. J. Nicholls, G. J. Dusting, B. Cutri, S. Bao, G. R. Drummond, K.-A. Rye, and P. J. Barter Reconstituted High-Density Lipoproteins Inhibit the Acute Pro-Oxidant and Proinflammatory Vascular Changes Induced by a Periarterial Collar in Normocholesterolemic Rabbits Circulation, March 29, 2005; 111(12): 1543 - 1550. [Abstract] [Full Text] [PDF]

				P. J. Barter, S. Nicholls, K.-A. Rye, G.M. Anantharamaiah, M. Navab, and A. M. Fogelman Antiinflammatory Properties of HDL Circ. Res., October 15, 2004; 95(8): 764 - 772. [Abstract] [Full Text] [PDF]

				A. V. Bocharov, I. N. Baranova, T. G. Vishnyakova, A. T. Remaley, G. Csako, F. Thomas, A. P. Patterson, and T. L. Eggerman Targeting of Scavenger Receptor Class B Type I by Synthetic Amphipathic {alpha}-Helical-containing Peptides Blocks Lipopolysaccharide (LPS) Uptake and LPS-induced Pro-inflammatory Cytokine Responses in THP-1 Monocyte Cells J. Biol. Chem., August 20, 2004; 279(34): 36072 - 36082. [Abstract] [Full Text] [PDF]

				G. Assmann and A. M. Gotto Jr HDL Cholesterol and Protective Factors in Atherosclerosis Circulation, June 15, 2004; 109(23_suppl_1): III-8 - III-14. [Abstract] [Full Text]

				M. K. Liisanantti, M. L. Hannuksela, M. E. Ramet, and M. J. Savolainen Lipoprotein-Associated Phosphatidylethanol Increases the Plasma Concentration of Vascular Endothelial Growth Factor Arterioscler. Thromb. Vasc. Biol., June 1, 2004; 24(6): 1037 - 1042. [Abstract] [Full Text] [PDF]

				G. A. Kaysen and J. P. Eiserich The Role of Oxidative Stress-Altered Lipoprotein Structure and Function and Microinflammation on Cardiovascular Risk in Patients with Minor Renal Dysfunction J. Am. Soc. Nephrol., March 1, 2004; 15(3): 538 - 548. [Abstract] [Full Text] [PDF]

				L. J Miller and R. Chacko The Role of Cholesterol and Statins in Alzheimer's Disease Ann. Pharmacother., January 1, 2004; 38(1): 91 - 98. [Abstract] [Full Text] [PDF]

				P. G. Frank, H. Lee, D. S. Park, N. N. Tandon, P. E. Scherer, and M. P. Lisanti Genetic Ablation of Caveolin-1 Confers Protection Against Atherosclerosis Arterioscler. Thromb. Vasc. Biol., January 1, 2004; 24(1): 98 - 105. [Abstract] [Full Text] [PDF]

				L. Calabresi, M. Gomaraschi, and G. Franceschini Endothelial Protection by High-Density Lipoproteins: From Bench to Bedside Arterioscler. Thromb. Vasc. Biol., October 1, 2003; 23(10): 1724 - 1731. [Abstract] [Full Text] [PDF]

				C. Thiemermann, N. S.A. Patel, E. O. Kvale, G. W. Cockerill, P. A.J. Brown, K. N. Stewart, S. Cuzzocrea, D. Britti, H. Mota-Filipe, and P. K. Chatterjee High Density Lipoprotein (HDL) Reduces Renal Ischemia/Reperfusion Injury J. Am. Soc. Nephrol., July 1, 2003; 14(7): 1833 - 1843. [Abstract] [Full Text] [PDF]

				C. Parolini, G. Chiesa, Y. Zhu, T. Forte, S. Caligari, E. Gianazza, M. G. Sacco, C. R. Sirtori, and E. M. Rubin Targeted Replacement of Mouse Apolipoprotein A-I with Human ApoA-I or the Mutant ApoA-IMilano. EVIDENCE OF APOA-IM IMPAIRED HEPATIC SECRETION J. Biol. Chem., February 7, 2003; 278(7): 4740 - 4746. [Abstract] [Full Text] [PDF]

				F. Parhami, B. Basseri, J. Hwang, Y. Tintut, and L. L. Demer High-Density Lipoprotein Regulates Calcification of Vascular Cells Circ. Res., October 4, 2002; 91(7): 570 - 576. [Abstract] [Full Text] [PDF]

				B. J. O'Connell and J. Genest Jr High-Density Lipoproteins and Endothelial Function Circulation, October 16, 2001; 104(16): 1978 - 1983. [Abstract] [Full Text] [PDF]