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RECEPTORS AND SIGNAL TRANSDUCTION
Department of Physiology, Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania
Submitted 28 July 2005 ; accepted in final form 14 November 2005
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ABSTRACT |
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 TOP ABSTRACT RESULTSDISCUSSIONGRANTSREFERENCES |
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allograft inflammatory factor-1; cell activation; small interfering RNA
Allograft inflammatory factor-1 (AIF-1) is a 143-amino acid, cytoplasmic, evolutionarily conserved, calcium-binding protein. AIF-1 has signatures of a cytoplasmic signaling protein, including several motifs capable of interacting with PDZ domains, which are important in mediating interactions of large multiprotein complexes, and the QXXER motif, shown to mediate G
interactions (8, 18). AIF-1 expression was originally reported to be restricted to cells of the monocyte/macrophage lineage, as well as in microglial and dendritic cells (11). Multiple reports from several investigators in varied experimental systems indicate that on the basis of its expression in infiltrating macrophages in inflamed tissue, AIF-1 expression can be considered a marker of activated macrophages. For example, Utans et al. (30) found that AIF-1 was expressed in activated macrophages in chronic (Lewis to F344 rats) cardiac transplants. In these studies, AIF-1 immunolocalized to macrophages infiltrating the myocardium at 7 days posttransplant and persisted in these cells to 75 days posttransplant. In renal biopsies, of several markers tested, including leukocyte surface antigens, cytokines, and activation markers, AIF-1-positive macrophages were the only marker able to distinguish subclinical from clinical rejection (14). AIF-1 also localized to the macrophage infiltrate of pancreatic islets in prediabetic rats (7). In skeletal muscle, AIF-1 expression was observed in macrophages within 48 h postdevascularization (20). AIF-1 was found to be expressed in infiltrating macrophages in experimental autoimmune encephalomyelitis and neuritis, as well as in parenchymal cells in human brain infarcts and traumatic brain injury (26). Robust AIF-1 expression is detected in the allograft response of the phylogenetically distant species carp and marine sponges (13, 19). It is clear from this work that AIF-1 expression is a conserved response in inflammatory reactions.
Despite numerous studies that have correlated increases in AIF-1 expression with activated macrophages, a defined function for this protein in macrophage activation, and more specifically in the development of atherosclerosis, has yet to be elucidated. Previous work by our group (1–4, 17) focused on cytokine-inducible AIF-1 expression in activated VSMC and showed that AIF-1 expression regulates VSMC migration and proliferation. Receptor-initiated signaling, migration, and proliferation are all hallmarks of macrophage activation. On the basis of these functional data, together with the numerous reports associating AIF-1 expression with activated macrophages, we hypothesized that AIF-1 activity is central for macrophage activation. In this study, we report that AIF-1 expression colocalizes with CD68+ macrophages in human atherosclerotic arteries and that AIF-1 expression is inducible in macrophages by oxidized LDL. Furthermore, reduction of AIF-1 expression in macrophages by small interfering RNA (siRNA) abrogates their migration and proliferation and also attenuates atherogenic signal transduction cascades.
MATERIALS AND METHODS Immunofluorescence. Human coronary arteries recovered from hearts removed from patients at the time of cardiac transplantation were fixed in 10% buffered formalin, embedded in paraffin, sectioned at 5 µm, deparaffinized in Xylene, and rehydrated through graded alcohols as described previously (3). Antigen unmasking was performed, and after blocking with 2% goat serum, sections were incubated with primary antibodies for 1 h at room temperature, followed by a 30-min incubation with secondary antibody conjugated to Alexa Fluor 568 (red) and Alexa Fluor 488 (green) (Molecular Probes). CD68 (macrophage marker; Neo Markers) were used at a concentration of 1.0 µg/ml, and AIF-1 antibody was used at 0.5 µg/ml.
siRNA expression plasmids. siRNA constructs used were synthesized by GenScript (Scotch Plains, NJ). Three prospective 19-bp regions of murine AIF-1 mRNA were targeted (5' to 3'): construct 1, AGAGAGGCTGGATGAGATC; construct 2, ACAAGCAATTCCTAGACGA; and construct 3, TAGCAGTGATGAGGATCTG. They were chemically synthesized as part of a small, double-stranded 70-bp DNA insert containing the target sequence in the sense orientation, followed by a short loop region, the target in the antisense orientation, and six thymidines added to the 3' end, which serves as a polymerase III transcription termination site. This insert was flanked by BamHI and HindIII restriction sites and cloned into the siRNA expression vector pRNA-U6.1/shuttle (pShuttle), containing a RNA polymerase III promoter, which initiates the transcription of a short hairpin RNA rapidly processed by cellular machinery into 19- to 22-nt double-stranded RNA (siRNA). The pShuttle plasmid contains the selectable marker Neomycin to facilitate selection of stably transfected cells.
Cell culture and stable transfections. RAW264.7 cells, a commonly used mouse macrophage cell line, were obtained from the American Type Culture Collection. RAW264.7 were utilized because they constitutively express low levels of AIF-1 mRNA (29) and are adherent, facilitating positive selection of stable transfectants. RAW264.7 cells were cultured in DMEM with 10% FCS, 100 IU/ml penicillin, and 50 mg/ml streptomycin. Vector alone (pRNA-U6.1/shuttle) was used as a negative control. Lipid-mediated transfection with pRNA-U6.1/shuttle plasmid alone or with pRNA-U6.1/shuttle AIF-1/siRNA was performed as described previously (4). After antibiotic selection (400 µg/ml G418; Fisher Biotechnology), transfectants were pooled to avoid the effects of clonal selection and were expanded in 125 µg/ml G418. For rescue, cells stably transfected with AIF-1 siRNA were incubated with AIF-1 adenovirus (AdAIF; 50 multiplicities of infection) for 2 h. Primary human monocytes were obtained by venipuncture from normal, healthy individuals, separated from red blood cells by Ficoll-Hypaque centrifugation, and separated from lymphocytes and granulocytes by adherence to plastic for 2 h at 37°C. Adherent cells were cultured and stimulated as described for RAW264.7 cells.
Proliferation assay. Equal numbers of stable transfectants were seeded onto 12-well plates at a density of 7,500 cells/ml as described previously (4, 9). Medium was changed on the fourth day, and after 4 and 7 days, cells were counted using a standard hemocytometer.
Migration assay. Standard Boyden chamber migration assays were performed as described previously (2). Transwell Boyden chamber plates (6.5-mm diameter; Costar) with a 5-µm polycarbonate membrane pore size were seeded with stably transfected or adenovirally rescued cells (106 cells per membrane) in medium containing 0.5% FCS as described previously (2). Five nanograms of monocyte chemoattractant protein-1 (MCP-1; Sigma) were placed in the lower chamber, and cells were incubated for 3 h at 37°C, at which time cells were fixed and stained using Dif-Quick cell stain (American Hospital Supply). The upper layer was scraped free of cells. Cells that had migrated to the lower surface of the membrane were quantitated by counting four high-power fields per membrane. Experiments were performed in triplicate from three independently transfected groups of macrophages.
Oxidized LDL preparation. Human LDL was purchased from Sigma. For oxidation, LDL (1 mg/ml) was oxidized in PBS containing 20 µM copper sulfate at 37°C for 24 h as described previously (5, 15). Oxidation was arrested by addition of 1 mM EDTA (pH 8.5) and cooling. Protein concentration was determined using the Bradford assay method and applied within 1–3 days of preparation. For induction of AIF-1 expression, 20 µg/ml was used; for induction of signaling cascades, 20 µg/ml was used.
Western blotting.
For preparation of cell extracts, primary human or RAW264.7 cells were washed with PBS and lysed by adding 2x SDS sample buffer [125 mM Tris·HCl (pH 6.8 at 25°C), 4% (wt/vol) SDS, 1.6% (vol/vol) -mercaptoethanol, 20% glycerol, and 0.02% (wt/vol) bromphenol blue] as described previously (21). Extract proteins were separated using SDS-PAGE, transferred onto a nitrocellulose membrane, and blocked as described previously (9). AIF-1 rabbit polyclonal antibody (1:3,000 dilution) as described previously (14), a 1:750 dilution of Multiplex Western Cocktail I (containing anti-phospho-p90, Akt, p44/42, and S6), and anti-phospho-p38 (Cell Signaling Technology) as well as a 1:2,000 dilution of secondary antibody were used. Monoclonal active caspase-3 antibody (1:2,500 dilution) was obtained from BD Pharmingen. Equal loading of protein extracts on gels was verified by Ponceau S staining of the membrane and blotting with total p38, p90, Akt, p44/42, and S6 protein, as well as with the housekeeping protein anti-GAPDH (1:5,000 dilution; Biogenesis), and reactive proteins were visualized using enhanced chemiluminescence. To induce AIF-1 expression, we incubated human monocytes or RAW264.7 cells with oxidized LDL (20 µg/ml) for the indicated times. For detection of activation of intracellular signaling proteins, cells were rinsed in PBS, starved in 0.5% DMEM for 48 h, and stimulated with 20% T-lymphocyte conditioned medium or oxidized LDL (20 µg/ml) for the indicated times. Staurosporine was used at 5 µM for 24 h as a positive control for induction of apoptosis (33).
Statistical analysis.
Experiments were repeated three times. Results from proliferation and migration are presented as means ± SD and were compared using one-way ANOVA. Results form cell signaling transduction are presented as means ± SE and were compared using two-way ANOVA and Bonferroni posttests. A value of P 
0.05 was considered significant.
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52% more slowly than do control vector-only cells (255 x 103 ± 20 and 583 x 103 ± 34 for siRNA construct 1 and control cells, respectively; P < 0.01). Untransfected control cells or other siRNA sequences that do not knock down AIF-1 expression have no inhibitory effect (Fig. 2B). Consequently, cells transfected with siRNA construct 1 were used for subsequent experiments. To specify that growth inhibition was due to abrogation of AIF-1 expression, we infected siRNA construct 1 cells with AdAIF-1 to rescue AIF-1 expression. These experiments show that restoration of AIF-1 expression rescued the ability of these cells to proliferate by 170% (431 x 103 ± 67 and 1,160 x 103 ± 73 for siRNA and siRNA infected with AdAIF-1, respectively; P < 0.001) (Fig. 3). Moreover, cells infected with AdAIF-1 grew 37% more rapidly than did control cells (845 x 103 ± 91 for control and 1,160 x 103 ± 73 for rescued cells, respectively; P < 0.005). siRNA cells infected with green fluorescent protein adenovirus (AdGFP) showed no change in growth capacity (data not shown).
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DISCUSSION |
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AIF-1 expression in human arteries with transplant vasculopathy and in cytokine-stimulated macrophages has been reported (3, 29–31). Induction of AIF-1 expression is at the transcriptional level (4, 29, 30). AIF-1 mRNA has been identified as one of a number of transcripts representative of the atherosclerotic burden in human aorta (27). Nevertheless, no link has been made between AIF-1 expression and function in the development of atherosclerosis. In our analysis, AIF-1 protein localization in macrophages in atherosclerotic human arteries suggested the additional possibility of induction by oxidized lipids. This study is the first to demonstrate that oxidized LDL, but not native LDL, is a strong inducer of AIF-1 protein expression in monocytes/macrophages.
The functional consequences of AIF-1 expression in macrophages has not been determined; therefore, we used siRNA technology to reduce AIF-1 expression in these cells. Vector-based delivery, rather than transfection of oligonucleotides, was used because it has been found to be more effective than synthetic siRNA for inhibition of gene expression, likely as a result of increased stability (6). Use of an antibiotic-selectable vector also allowed the establishment of stable cell lines expressing consistent and reproducible amounts of siRNA to reduce experimental variability. Replication of macrophages in the atherosclerotic plaque has been reported by some investigators (24) but remains controversial in humans. However, monocyte/macrophage replication is an important component of inflammation. An AIF-1 siRNA sequence that effectively knocked down protein expression significantly reduced macrophage expression, whereas other siRNA sequences that did not reduce AIF-1 expression did not reduce proliferation. Furthermore, when AIF-1 expression in the siRNA macrophages was rescued with AdAIF-1, the proliferative capacity was not only restored but enhanced. It was possible that abrogation of AIF-1 expression would be deleterious to the cell and initiate apoptosis, which would be reflected in lower cell numbers in the proliferation assay. This also was a concern in light of suppression of Akt activation in the siRNA-expressing cells. This is not the case, because siRNA-expressing cells do not express active caspase-3, a sensitive and specific marker of cellular apoptosis. This finding confirms a tight association between AIF-1 expression and cell proliferation and is consistent with our previous findings in VSMC in which overexpression enhanced proliferation (4, 9). Other investigators found that overexpression of AIF-1 in RAW264.7 macrophages resulted in increased IL-10 and IL-12 production in response to lipopolysaccharide stimulation (32). In this study, we were unable to detect any decrease in these cytokines with siRNA treatment. In addition, we determined that abrogation of AIF-1 expression significantly reduced migration of macrophages. This inhibition also could be rescued by infection with AdAIF-1 and is consistent with our previous report (2) indicating that AIF-1 plays a role in VSMC migration.
Multiple studies have shown that receptor-mediated oxidized LDL uptake triggers signal transduction cascades, cytokine synthesis, and macrophage activation (15, 18, 23). AIF-1 is a cytoplasmic calcium-binding protein. Binding of calcium to regulatory EF-hand proteins induces a conformational change that often mediates signaling cascades. AIF-1 also includes several motifs capable of interacting with PDZ interaction domains, which are important in regulating interactions of multiprotein complexes (8, 17). Together, these characteristics suggested that reduction of AIF-1 protein expression might interrupt signaling cascades important in macrophage activation.
Reduction of AIF-1 expression significantly inhibited oxidized LDL activation of Akt and p44/42 MAPK, which is noteworthy in that activation of both of these kinases has been shown to be essential in oxidized LDL-mediated macrophage activation (17, 27). Absence of AIF-1 inhibited basal but not oxidized LDL-mediated activation of p38 kinase, suggesting that AIF-1 mediates activation of a kinase proximal to basal p38 phosphorylation but not those directly involved in oxidized LDL-initiated activation. This finding is relevant in that p38 activation is a necessary component of macrophage proliferation and migration (22, 27). Consequently, inhibition of basal levels of p38 phosphorylation in AIF-1 siRNA cells may provide a mechanism for their impaired proliferative capacity. Other kinases activated by oxidized LDL were not inhibited by reduction of AIF-1 expression, suggesting a specificity of pathways mediated by AIF-1. T-lymphocyte-conditioned medium contains multiple inflammatory and growth factors secreted by activated lymphocytes and closely mirrors the in vivo situation in which multiple signaling cascades are active. Reduction of AIF-1 results in a significant inhibition of p38 activation at 5 and 15 min poststimulation. Basal levels of p38 also are inhibited, but not significantly. In contrast to oxidized LDL, no significant inhibition of p44/42 MAPK or Akt was noted, likely because of cross talk from the multiple stimuli present in T-cell-conditioned medium. The differences noted between conditioned medium and oxidized LDL may reflect differences between the signaling pathways utilized by each stimuli or the specificity of the pathway that AIF-1 mediates. Together, these data indicate a close association between AIF-1 expression and activation of signal transduction cascades mediated by atherogenic stimuli.
The most direct explanation for these inhibitory effects is that based on its protein structure, in which AIF-1 acts as a scaffold protein that anchors members of signaling cascades into reactive proximity. In the absence of AIF-1, cascades are interrupted, resulting in suppressed activation of kinases distal from AIF-1. In this sense, AIF-1 acts as an inflammation-responsive signal regulator in macrophages. We have not been able to show a direct interaction between AIF-1 and p38, Akt, or p44/42, suggesting that the effects of AIF-1 on these kinases are proximal to their activation. Alternatively, one study (32) reported that overexpression of AIF-1 in macrophages leads to increased LPS-mediated IL-10 and IL-12 production. Although an alteration in expression of either of these cytokines with AIF-1 siRNA was not detected, the potential exists that inhibition of AIF-1 may abrogate autocrine production of cytokines, resulting in reduced basal signal transduction in siRNA-treated cells.
Although increased AIF-1 expression in activated macrophages has been described, there are several novel points to this study. First, AIF-1 is detected in macrophages in human atherosclerotic arteries, and its expression can be induced by stimulation with oxidized LDL but not native LDL. Second, knockdown of AIF-1 protein by stable transfection of siRNA reduces the important macrophage activities of proliferation and migration. These activities could be restored by rescue of AIF-1 expression. Apoptosis is not induced by AIF-1 siRNA. Third, the potential mechanism of these effects is a reduction in signal transduction, regardless of whether the stimuli comprise inflammatory cytokines or oxidized LDL. It is clear from multiple descriptive reports that AIF-1 expression is a fundamental part of the inflammatory process. The data presented in this study extend these reports and show that AIF-1 expression is crucial for macrophage activation, particularly in response to atherogenic stimuli.
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FOOTNOTES |
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The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
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REFERENCES |
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2. Autieri MV, Kelemen SE, and Wendt KW. AIF-1 is an actin-polymerizing and Rac1-activating protein that promotes vascular smooth muscle cell migration. Circ Res 92: 1107–1114, 2003.
3. Autieri MV, Kelemen SE, Thomas BA, Feller ED, Goldman BI, and Eisen HJ. Allograft inflammatory factor-1 (AIF-1) expression correlates with cardiac rejection and development of cardiac allograft vasculopathy. Circulation 106: 2218–2223, 2002.
4. Autieri MV, Mu A, and Carbone C. Expression of allograft inflammatory factor-1 (AIF1) is a marker of activated human VSMC and arterial injury. Arterioscler Thromb Vasc Biol 20: 1737–1744, 2000.
5. Brown AJ, Dean RT, and Jessup W. Free and esterified oxysterol: formation during copper-oxidation of low density lipoprotein and uptake by macrophages. J Lipid Res 37: 320–335, 1996.[Abstract]
6. Brummelkamp TR, Bernards R, and Agami R. A system for stable expression of short interfering RNAs in mammalian cells. Science 296: 550–553, 2002.
7. Chen ZW, Ahren B, Ostenson CG, Cintra A, Bergman T, Moller C, Fuxe K, Mutt V, Jornvall H, and Efendic S. Identification, isolation, and characterization of daintain (allograft inflammatory factor 1), a macrophage polypeptide with effects on insulin secretion and abundantly present in the pancreas of prediabetic BB rats. Proc Natl Acad Sci USA 94: 13879–13884, 1997.
8. Chen J, DeVivo M, Dingus J, Harry A, Li J, Sui J, Carty DJ, Blank JL, Exton JH, Stoffel RH, Inglese J, Lefkowitz RJ, Logothetis DE, Hildebrandt JD, and Iyengar R. A region of adenylyl cyclase 2 critical for regulation by G protein beta gamma subunits. Science 268: 1166–1169, 1995.
9. Chen X, Kelemen SE, and Autieri MV. AIF-1 expression modulates proliferation of human vascular smooth muscle cells by autocrine expression of G-CSF. Arterioscler Thromb Vasc Biol 21: 1–7, 2004.
10. Chung SW, Kang BY, Kim SH, Pak YK, Cho D, Trinchieri G, and Kim TS. Oxidized low density lipoprotein inhibits interleukin-12 production in lipopolysaccharide-activated mouse macrophages via direct interactions between peroxisome proliferator-activated receptor- and nuclear factor-
B. J Biol Chem 275: 32681–32687, 2000.
11. Deininger MH, Meyermann R, and Schluesener HJ. The allograft inflammatory factor-1 family of proteins. FEBS Lett 514: 115–121, 2002.[CrossRef][Web of Science][Medline]
12. Feng Y, Schreiner GF, Chakravarty S, Liu DY, and Joly AH. Inhibition of the mitogen activated protein kinase, p38 alpha, prevents proinflammatory cytokine induction by human adherent mononuclear leukocytes in response to lipid loading. Atherosclerosis 158: 331–338, 2001.[CrossRef][Web of Science][Medline]
13. Fukiki K, Shin DH, Nakao M, and Yano T. Molecular cloning of carp CC chemokine, CXC, chemokine receptors, allograft inflammatory factor-1, and natural killer cell enhancing factor by use of suppression subtractive hybridization. Immunogenetics 49: 909–914, 1999.[CrossRef][Web of Science][Medline]
14. Grimm PC, McKenna R, Nickerson P, Russell ME, Gough J, Gospodarek E, Liu B, Jeffery J, and Rush DN. Clinical rejection is distinguished from subclinical rejection by increased infiltration by a population of activated macrophages. J Am Soc Nephrol 10: 1582–1589, 1999.
15. Hamilton JA, Myers D, Jessup W, Cochrane F, Byrne R, Whitty G, and Moss S. Oxidized LDL can induce macrophage survival, DNA synthesis, and enhanced proliferative response to CSF-1 and GM-CSF. Arterioscler Thromb Vasc Biol 19: 98–105, 1999.
16. Hansson GK. Inflammation, atherosclerosis, and coronary artery disease. N Engl J Med 352: 1685–1695, 2005.
17. Hung AY and Sheng M. PDZ domains: structural modules for protein complex assembly. J Biol Chem 277: 5699–5702, 2002.
18. Kamanna VS, Pai R, Roh DD, and Kirschenbaum MA. Oxidative modification of low-density lipoprotein enhances the murine mesangial cell cytokines associated with monocyte migration, differentiation, and proliferation. Lab Invest 74: 1067–1079, 1996.[Web of Science][Medline]
19. Kruse Steffen M, R, Batel R, Muler I, and Muller W. Differential expression of allograft inflammatory factor 1 and of glutathione peroxidase during auto- and allograft response in marine sponges. J Cell Sci 112: 4305–4313, 1999.[Abstract]
20. Kuschel R, Deininger MH, Meyermann R, Bornemann A, Yablonka-Reuveni Z, and Schluesener HJ. Allograft inflammatory factor-1 is expressed by macrophages in injured skeletal muscle and abrogates proliferation and differentiation of satellite cells. J Neuropathol Exp Neurol 59: 323–332, 2000.[Web of Science][Medline]
21. Mifune M, Ohtsu H, Suzuki H, Frank GD, Inagami T, Utsunomiya H, Dempsey PJ, and Eguchi S. Signal transduction of betacellulin in growth and migration of vascular smooth muscle cells. Am J Physiol Cell Physiol 287: C807–C813, 2004.
22. Nick JA, Young SK, Brown KK, Avdi NJ, Arndt PG, Suratt BT, Janes MS, Henson PM, and Worthen GS. Role of p38 mitogen-activated protein kinase in a murine model of pulmonary inflammation. J Immunol 164: 2151–2159, 2000.
23. Kusuhara MO, Chait A, Cader A, and Berk BC. Oxidized LDL stimulates mitogen-activated protein kinases in smooth muscle cells and macrophages. Arterioscler Thromb Vasc Biol 17: 141–148, 1997.
24. Rosenfeld ME and Ross R. Macrophage and smooth muscle cell proliferation in atherosclerotic lesions of WHHL and comparably hypercholesterolemic fat-fed rabbits. Arteriosclerosis 10: 680–687, 1990.
25. Ross R. The pathogenesis of atherosclerosis: a perspective for the 1990s. Nature 362: 801–809, 1993.[CrossRef][Medline]
26. Schluesener HJ, Seid K, and Meyermann R. Effects of autoantigen and dexamethasone treatment on expression of endothelial-monocyte activating polypeptide II and allograft-inflammatory factor-1 by activated macrophages and microglial cells in lesions of experimental autoimmune encephalomyelitis, neuritis, and uveitis. Acta Neuropathol (Berl) 97: 119–126, 1999.[CrossRef][Medline]
27. Senokuchi T, Matsumura T, Sakai M, Matsuo T, Yano M, Kiritoshi S, Sonoda K, Kukidome D, Nishikawa T, and Araki E. Extracellular signal-regulated kinase and p38 mitogen-activated protein kinase mediate macrophage proliferation induced by oxidized low-density lipoprotein. Atherosclerosis 176: 233–245, 2004.[CrossRef][Web of Science][Medline]
28. Seo D, Wang T, Dressman H, Herderick EE, Iversen ES, Dong C, Vata K, Milano CA, Rigat F, Pittman J, Nevins JR, West M, and Goldschmidt-Clermont PJ. Gene expression phenotypes of atherosclerosis. Arterioscler Thromb Vasc Biol 24: 1922–1927, 2004.
29. Sibinga NE, Feinberg MW, Yang H, Werner F, and Jain MK. Macrophage-restricted and interferon gamma-inducible expression of the allograft inflammatory factor-1 gene requires Pu.1. J Biol Chem 277: 16202–16210, 2002.
30. Utans U, Arceci R, Yamashita Y, and Russell M. Cloning and characterization of allograft inflammatory factor-1: a novel macrophage factor identified in rat cardiac allografts with chronic rejection. J Clin Invest 95: 2954–2962, 1995.[Web of Science][Medline]
31. Utans U, Quist WC, McManus BM, Wilson JE, Arceci RJ, Wallace AF, and Russell ME. Allograft inflammatory factory-1. A cytokine-responsive macrophage molecule expressed in transplanted human hearts. Transplantation 61: 1387–1392, 1996.[CrossRef][Web of Science][Medline]
32. Watano K, Iwabuchi K, Fujii S, Ishimori N, Mitsuhashi S, Ato M, Kitabatake A, and Onoe K. Allograft inflammatory factor-1 augments production of interleukin-6, -10 and -12 by a mouse macrophage line. Immunology 104: 307–316, 2001.[CrossRef][Web of Science][Medline]
33. Yamaki K, Hong J, Hiraizumi K, Ahn JW, Zee O, and Ohuchi K. Participation of various kinases in staurosporine induced apoptosis of RAW 264.7 cells. J Pharm Pharmacol 54: 1535–1544, 2002.[CrossRef][Web of Science][Medline]
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P < 0.057, compared with control cells at the same time point (n = 3).