RESUMEN
To carry out their physiological responsibilities, CD4+ T lymphocytes interact with various tissues of different mechanical properties. Recent studies suggest that T cells migrate upstream on surfaces expressing intracellular adhesion molecule-1 (ICAM-1) through interaction with leukocyte function-associated antigen-1 (αLß2) (LFA-1) integrins. LFA-1 likely behaves as a mechanosensor, and thus we hypothesized that substrate mechanics might affect the ability of LFA-1 to support upstream migration of T cells under flow. Here we measured motility of CD4+ T lymphocytes on polyacrylamide gels with predetermined stiffnesses containing ICAM-1, vascular cell adhesion molecule-1 (VCAM-1), or a 1:1 mixture of VCAM-1/ICAM-1. Under static conditions, we found that CD4+ T cells exhibit an increase in motility on ICAM-1, but not on VCAM-1 or VCAM-1/ICAM-1 mixed, surfaces as a function of matrix stiffness. The mechanosensitivity of T-cell motility on ICAM-1 is overcome when VLA-4 (very late antigen-4 [α4ß1]) is ligated with soluble VCAM-1. Last, we observed that CD4+ T cells migrate upstream under flow on ICAM-1-functionalized hydrogels, independent of substrate stiffness. In summary, we show that CD4+ T cells under no flow respond to matrix stiffness through LFA-1, and that the cross-talk of VLA-4 and LFA-1 can compensate for deformable substrates. Interestingly, CD4+ T lymphocytes migrated upstream on ICAM-1 regardless of the substrate stiffness, suggesting that flow can compensate for substrate stiffness.
Asunto(s)
Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/fisiología , Integrinas/metabolismo , Resinas Acrílicas/química , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Movimiento Celular , Humanos , Hidrogeles/química , Integrina alfa4beta1/química , Integrina alfa4beta1/metabolismo , Molécula 1 de Adhesión Intercelular/química , Molécula 1 de Adhesión Intercelular/metabolismo , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Mecanotransducción Celular , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Sarcomeric signaling complexes are important to sustain proper sarcomere structure and function, however, the mechanisms underlying these processes are not fully elucidated. In a gene trap experiment, we found that vascular cell adhesion protein 1 isoform X2 (VCAP1X2) mutant embryos displayed a dilated cardiomyopathy phenotype, including reduced cardiac contractility, enlarged ventricular chamber and thinned ventricular compact layer. Cardiomyocyte and epicardial cell proliferation was decreased in the mutant heart ventricle, as was the expression of pAKT and pERK. Contractile dysfunction in the mutant was caused by sarcomeric disorganization, including sparse myofilament, blurred Z-disc, and decreased gene expression for sarcomere modulators (smyd1b, mypn and fhl2a), sarcomeric proteins (myh6, myh7, vmhcl and tnnt2a) and calcium regulators (ryr2b and slc8a1a). Treatment of PI3K activator restored Z-disc alignment while injection of smyd1b mRNA restored Z-disc alignment, contractile function and cardiomyocyte proliferation in ventricles of VCAP1X2 mutant embryos. Furthermore, injection of VCAP1X2 variant mRNA rescued all phenotypes, so long as two cytosolic tyrosines were left intact. Our results reveal two tyrosine residues located in the VCAP1X2 cytoplasmic domain are essential to regulate cardiac contractility and the proliferation of ventricular cardiomyocytes and epicardial cells through modulating pAKT and pERK expression levels.
Asunto(s)
Molécula 1 de Adhesión Celular Vascular/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Animales , Calcio/metabolismo , Proliferación Celular , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ventrículos Cardíacos/metabolismo , Mutagénesis , Contracción Miocárdica , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Miofibrillas/metabolismo , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Fosforilación , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sarcómeros/química , Sarcómeros/fisiología , Intercambiador de Sodio-Calcio/genética , Intercambiador de Sodio-Calcio/metabolismo , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/genética , Proteínas de Pez Cebra/química , Proteínas de Pez Cebra/genéticaRESUMEN
Chemokine (C-C motif) ligand 25 (CCL25) and C-X-C motif chemokine 10 (CXCL10) induce the ligand-specific activation of integrin α4ß7 to mediate the selective adhesion of lymphocytes to mucosal vascular addressin cell adhesion molecule-1 (MAdCAM-1) or vascular cell adhesion molecule-1 (VCAM-1). However, the mechanism underlying the selective binding of different ligands by α4ß7 remains obscure. In this study, we demonstrate that CCL25 and CXCL10 induce distinct active conformers of α4ß7 with a high affinity for either MAdCAM-1 or VCAM-1. Single-cell force measurements show that CCL25 increases the affinity of α4ß7 for MAdCAM-1 but decreases its affinity for VCAM-1, whereas CXCL10 has the opposite effect. Structurally, CCL25 induces a more extended active conformation of α4ß7 compared with CXCL10-activated integrin. These two distinct intermediate open α4ß7 conformers selectively bind to MAdCAM-1 or VCAM-1 by distinguishing their immunoglobulin domain 2. Notably, Mn2+ fully opens α4ß7 with a high affinity for both ligands. Thus, integrin α4ß7 adopts different active conformations to switch its ligand-binding specificity.
Asunto(s)
Integrinas/química , Sitios de Unión , Adhesión Celular/genética , Moléculas de Adhesión Celular , Quimiocina CXCL10/química , Quimiocina CXCL10/metabolismo , Quimiocinas CC/química , Quimiocinas CC/metabolismo , Humanos , Inmunoglobulinas/química , Inmunoglobulinas/metabolismo , Ligandos , Linfocitos/metabolismo , Modelos Moleculares , Mucoproteínas/química , Mucoproteínas/metabolismo , Conformación Proteica , Dominios Proteicos , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Abdominal aortic aneurysm (AAA) is an often deadly disease without medical, non-invasive treatment options. The upregulation of vascular cell adhesion molecule-1 (VCAM-1) on aortic endothelium provides an early target epitope for a novel biotechnological theranostic approach. MicroRNA-126 was used as a therapeutic agent, based on its capability to downregulate VCAM-1 expression in endothelial cells and thereby reduces leukocyte adhesion and exerts anti-inflammatory effects. Ultrasound microbubbles were chosen as carriers, allowing both molecular imaging as well as targeted therapy of AAA. Microbubbles were coupled with a VCAM-1-targeted single-chain antibody (scFvmVCAM-1) and a microRNA-126 mimic (M126) constituting theranostic microbubbles (TargMB-M126). TargMB-M126 downregulates VCAM-1 expression in vitro and in an in vivo acute inflammatory murine model. Most importantly, using TargMB-M126 and ultrasound-guided burst delivery of M126, the development of AAA in an angiotensin-II-induced mouse model can be prevented. Overall, we describe a unique biotechnological theranostic approach with the potential for early diagnosis and long-sought-after medical therapy of AAA.
Asunto(s)
Aneurisma de la Aorta Abdominal/genética , Aneurisma de la Aorta Abdominal/patología , Terapia Genética , MicroARNs/genética , Animales , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/terapia , Biomarcadores , Células Cultivadas , Modelos Animales de Enfermedad , Células Endoteliales , Técnicas de Transferencia de Gen , Terapia Genética/métodos , Inmunohistoquímica , Masculino , Ratones , Ratones Noqueados , MicroARNs/administración & dosificación , MicroARNs/química , Imagen Molecular , Anticuerpos de Cadena Única/farmacología , Ultrasonografía , Molécula 1 de Adhesión Celular Vascular/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
OBJECTIVE: To examine some anthropometric parameters, arterial stiffness, lipid profile, and soluble adhesion molecules in young adults with reduced physical activity. MATERIAL AND METHODS: The study is carried on 54 healthy young adults aged 20.97 ± 2.04 years. Two groups: 23 with reduced physical activity (INAC) and 31 with optimal physical activity (AC). Body mass index (BMI), basal metabolic rate (BMR), central aortic systolic blood pressure (CSBP, mmHg), plasma atherogenic index (AIP), and serum soluble cell adhesion molecules (sICAM-1, sVCAM-1) are followed up. RESULTS: CSBP [115.56 ± 10.22 vs. 105.13 ± 9.88*], AIP [-0.04 ± 0.18 vs. -0.08 ± 0.08**] and sICAM-1 [362.5 ± 49.95 vs. 281.75 ± 80.39**] are significantly higher, and BMR [1431 ± 297.9 vs. 1674.6 ± 365.57*] is significantly lower in the physically inactive young healthy adults. CONCLUSIONS: CSBP, AIP, and sICAM-1 are higher in young adults with reduced physical activity. This plays substantial role in the acceleration of atherogenic process and in long-term perspective could promote cardiovascular diseases.
Asunto(s)
Enfermedades Asintomáticas , Aterosclerosis/fisiopatología , Molécula 1 de Adhesión Intercelular/sangre , Prehipertensión/fisiopatología , Conducta Sedentaria , Regulación hacia Arriba , Rigidez Vascular , Adolescente , Adulto , Enfermedades Asintomáticas/epidemiología , Enfermedades Asintomáticas/terapia , Aterosclerosis/epidemiología , Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Metabolismo Basal , Biomarcadores/sangre , Bulgaria/epidemiología , Ejercicio Físico , Estudios de Seguimiento , Humanos , Molécula 1 de Adhesión Intercelular/química , Prehipertensión/epidemiología , Prehipertensión/metabolismo , Prehipertensión/prevención & control , Factores de Riesgo , Índice de Severidad de la Enfermedad , Solubilidad , Estudiantes de Odontología , Estudiantes de Medicina , Molécula 1 de Adhesión Celular Vascular/sangre , Molécula 1 de Adhesión Celular Vascular/química , Adulto JovenRESUMEN
The biophysical fine-tuning of cancer cell plasticity is crucial for tumor progression but remains largely enigmatic. Although vascular cell adhesion molecule-1 (VCAM-1/CD106) has been implicated in melanoma progression, here its presentation on endothelial cells was associated with diminished melanoma cell spreading. Using a specific nanoscale modulation of VCAM-1 (tunable from 70 to 670 ligands/µm²) next to integrin ligands (RGD motifs) in a bifunctional system, reciprocal regulation of integrin α4 (ITGA4/VLA-4/CD49d)-dependent adhesion and spreading of melanoma cells was found. As the VCAM-1/VLA-4 receptor pair facilitated adhesion, while at the same time antagonizing RGD-mediated spreading, melanoma cell morphogenesis on these bifunctional matrices was directly regulated by VCAM-1 in a dichotomic and density-dependent fashion. This was accompanied by concordant regulation of F-actin cytoskeleton remodeling, Rac1-expression, and paxillin-related adhesion formation. The novel function of VCAM-1 was corroborated in vivo using two murine models of pulmonary metastasis. The regulation of melanoma cell plasticity by VCAM-1 highlights the complex regulation of tumor-matrix interactions.Implications: Nanotechnology has revealed a novel dichotomic function of the VCAM-1/VLA-4 interaction on melanoma cell plasticity, as nanoscale tuning of this interaction reciprocally determines adhesion and spreading in a ligand density-dependent manner. Mol Cancer Res; 16(3); 528-42. ©2017 AACR.
Asunto(s)
Integrina alfa4beta1/metabolismo , Melanoma/metabolismo , Melanoma/patología , Molécula 1 de Adhesión Celular Vascular/metabolismo , Animales , Adhesión Celular/fisiología , Línea Celular Tumoral , Plasticidad de la Célula/fisiología , Humanos , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Nanotecnología/métodos , Oligopéptidos/química , Transfección , Molécula 1 de Adhesión Celular Vascular/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/químicaRESUMEN
PURPOSE: The aim of the current meta-analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor necrosis factor (TNF), interleukin 6 (IL-6), C-reactive protein (CRP), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) in adults. METHODS: After a systemic search on PubMed, Embase, and Cochrane library and bibliographies of relevant articles, 25 randomized controlled trials that met the inclusion criteria were identified. RESULTS: No significant effect of dietary ALA supplementation was observed on TNF (SMD: -0.03, 95% CI -0.36 to 0.29), IL-6 (SMD: -0.17, 95% CI -0.46 to 0.12), CRP (SMD: -0.06, 95% CI -0.24 to 0.12), sICAM-1 (SMD: -0.06, 95% CI -0.26 to 0.13), and sVCAM-1 (SMD: -0.24, 95% CI -0.56 to 0.09). Subgroup analysis revealed that increasing dietary ALA tends to elevate CRP concentration in healthy subjects. However, the null effect of ALA supplementation on other inflammatory markers was not changed in various subgroups, indicating that the results are stable. Meta-regression results revealed a negative relationship between the effect size on CRP and its baseline concentration. No significant publication bias was observed for all inflammatory markers as suggested by funnel plot and Begg's test. CONCLUSION: Our meta-analysis did not find any beneficial effect of ALA supplementation on reducing inflammatory markers including TNF, IL-6, CRP, sICAM-1, and sVCAM-1. However, in healthy subjects, ALA supplementation might increase CRP concentration.
Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Enfermedad Crónica/prevención & control , Suplementos Dietéticos , Medicina Basada en la Evidencia , Mediadores de Inflamación/sangre , Ácido alfa-Linolénico/uso terapéutico , Antiinflamatorios no Esteroideos/efectos adversos , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Suplementos Dietéticos/efectos adversos , Humanos , Mediadores de Inflamación/química , Molécula 1 de Adhesión Intercelular/sangre , Molécula 1 de Adhesión Intercelular/química , Interleucina-6/sangre , Ensayos Clínicos Controlados Aleatorios como Asunto , Solubilidad , Factor de Necrosis Tumoral alfa/sangre , Molécula 1 de Adhesión Celular Vascular/sangre , Molécula 1 de Adhesión Celular Vascular/química , Ácido alfa-Linolénico/efectos adversosRESUMEN
Bone morphogenetic proteins 9 and 10 (BMP9/BMP10) are circulating cytokines with important roles in endothelial homeostasis. The aim of this study was to investigate the roles of BMP9 and BMP10 in mediating monocyte-endothelial interactions using an in vitro flow adhesion assay. Herein, we report that whereas BMP9/BMP10 alone had no effect on monocyte recruitment, at higher concentrations both cytokines synergized with tumor necrosis factor-α (TNFα) to increase recruitment to the vascular endothelium. The BMP9/BMP10-mediated increase in monocyte recruitment in the presence of TNFα was associated with up-regulated expression levels of E-selectin, vascular cell adhesion molecule (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) on endothelial cells. Using siRNAs to type I and II BMP receptors and the signaling intermediaries (Smads), we demonstrated a key role for ALK2 in the BMP9/BMP10-induced surface expression of E-selectin, and both ALK1 and ALK2 in the up-regulation of VCAM-1 and ICAM-1. The type II receptors, BMPR-II and ACTR-IIA were both required for this response, as was Smad1/5. The up-regulation of cell surface adhesion molecules by BMP9/10 in the presence of TNFα was inhibited by LDN193189, which inhibits ALK2 but not ALK1. Furthermore, LDN193189 inhibited monocyte recruitment induced by TNFα and BMP9/10. BMP9/10 increased basal IκBα protein expression, but did not alter p65/RelA levels. Our findings suggest that higher concentrations of BMP9/BMP10 synergize with TNFα to induce the up-regulation of endothelial selectins and adhesion molecules, ultimately resulting in increased monocyte recruitment to the vascular endothelium. This process is mediated mainly via the ALK2 type I receptor, BMPR-II/ACTR-IIA type II receptors, and downstream Smad1/5 signaling.
Asunto(s)
Receptores de Activinas Tipo I/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Endotelio Vascular/metabolismo , Factores de Diferenciación de Crecimiento/metabolismo , Monocitos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Receptores de Activinas Tipo I/antagonistas & inhibidores , Receptores de Activinas Tipo I/genética , Receptores de Activinas Tipo II/antagonistas & inhibidores , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Aorta , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Selectina E/química , Selectina E/genética , Selectina E/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/inmunología , Factor 2 de Diferenciación de Crecimiento , Humanos , Molécula 1 de Adhesión Intercelular/química , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Cinética , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Pirazoles/farmacología , Pirimidinas/farmacología , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/agonistas , Regulación hacia Arriba/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
AIM: The contribution of the inflammatory mediator interleukin-17 (IL-17) in nonsmall cell lung cancer (NSCLC) malignancy has been reported in the literature. MicroRNA-181a-5p (miR-181a-5p) acts as a tumor suppressor which can regulate target gene at the posttranscriptional level. Our study aimed to investigate the interaction between IL-17 and miR-181a-5p in NSCLC. METHODS: 35 patients with NSCLC and 24 COPD controls were selected and examined in our study. In vitro, H226 and H460 cell lines were exposed to different doses (20, 40, 60, and 80 ng/mL) of IL-17 to examine the effect of IL-17 on miR-181a-5p and vascular cell adhesion molecule 1 (VCAM-1) expression. MiR-181 mimic and miR-181a-5p inhibitor were transfected to explore the regulation of VCAM-1 as well as tumor cell proliferation and migration. RESULTS: miR-181a-5p expression was downregulated, and IL-17 and VCAM-1 expression was upregulated in NSCLC tissues. Furthermore, IL-17 decreased miR-181a-5p expression but increased VCAM-1 expression in H226 and H460 cells. MiR-181 regulated VCAM-1 expression through binding to 3'-UTR sequence. MiR-181 attenuated tumor cell proliferation and migration. IL-17 modulated miR-181a-5p expression through activating NF-κB but not Stat3. CONCLUSION: Taken together, our data show the regulation of VCAM-1 expression by miR-181a-5p under IL-17 exposure, predicting a potential way for counteracting cancer metastasis.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Interleucina-17/metabolismo , Neoplasias Pulmonares/patología , MicroARNs/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Adulto , Anciano , Antagomirs/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Estudios de Casos y Controles , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo/efectos de los fármacos , Femenino , Células HEK293 , Humanos , Interleucina-17/farmacología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Persona de Mediana Edad , FN-kappa B/antagonistas & inhibidores , FN-kappa B/genética , FN-kappa B/metabolismo , Interferencia de ARN , Factor de Transcripción STAT3/antagonistas & inhibidores , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/genéticaRESUMEN
Vascular cell adhesion molecule-1 (VCAM-1) is closely associated with tumor progression and metastasis. However, the relevance and role of VCAM-1 in lung cancer have not been clearly elucidated. In this study, we found that VCAM-1 was highly overexpressed in lung cancer tissue compared with that of normal lung tissue, and high VCAM-1 expression correlated with poor survival in lung cancer patients. VCAM-1 knockdown reduced migration of A549 human lung cancer cells into Matrigel, and competitive blocking experiments targeting the Ig-like domain 6 of VCAM-1 (VCAM-1-D6) demonstrated that the VCAM-1-D6 domain was critical for VCAM-1 mediated A549 cell migration into Matrigel. Next, we developed a human monoclonal antibody specific to human and mouse VCAM-1-D6 (VCAM-1-D6 huMab), which was isolated from a human synthetic antibody library using phage display technology. Finally, we showed that VCAM-1-D6 huMab had a nanomolar affinity for VCAM-1-D6 and that it potently suppressed the migration of A549 and NCI-H1299 lung cancer cell lines into Matrigel. Taken together, these results suggest that VCAM-1-D6 is a key domain for regulating VCAM-1-mediated lung cancer invasion and that our newly developed VCAM-1-D6 huMab will be a useful tool for inhibiting VCAM-1-expressing lung cancer cell invasion.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Movimiento Celular/efectos de los fármacos , Neoplasias Pulmonares/metabolismo , Molécula 1 de Adhesión Celular Vascular/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Sitios de Unión , Línea Celular Tumoral , Humanos , Ratones , Molécula 1 de Adhesión Celular Vascular/químicaRESUMEN
Tumor necrosis factor alpha (TNFα)-induced angiogenesis plays important roles in the progression of various diseases, including cancer, wet age-related macular degeneration, and rheumatoid arthritis. However, the relevance and role of vascular cell adhesion molecule-1 (VCAM-1) in angiogenesis have not yet been clearly elucidated. In this study, VCAM-1 knockdown shows VCAM-1 involvement in TNFα-induced angiogenesis. Through competitive blocking experiments with VCAM-1 Ig-like domain 6 (VCAM-1-D6) protein, we identified VCAM-1-D6 as a key domain regulating TNFα-induced vascular tube formation. We demonstrated that a monoclonal antibody specific to VCAM-1-D6 suppressed TNFα-induced endothelial cell migration and tube formation and TNFα-induced vessel sprouting in rat aortas. We also found that the antibody insignificantly affected endothelial cell viability, morphology and activation. Finally, the antibody specifically blocked VCAM-1-mediated cell-cell contacts by directly inhibiting VCAM-1-D6-mediated interaction between VCAM-1 molecules. These findings suggest that VCAM-1-D6 may be a potential novel therapeutic target in TNFα-induced angiogenesis and that antibody-based modulation of VCAM-1-D6 may be an effective strategy to suppress TNFα-induced angiogenesis.
Asunto(s)
Neovascularización Fisiológica , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Animales , Anticuerpos Monoclonales/farmacología , Movimiento Celular/efectos de los fármacos , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Dominios de Inmunoglobulinas , Masculino , Neovascularización Fisiológica/efectos de los fármacos , Ratas Sprague-Dawley , Molécula 1 de Adhesión Celular Vascular/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/químicaRESUMEN
The role of IL-1ß in regulating the expression of extracellular matrix (ECM) and cell adhesion genes in human adipocytes has been examined. Adipocytes differentiated in culture were incubated with IL-1ß for 4 or 24 h and RNA probed with PCR arrays for 84 ECM and cell adhesion genes. Treatment with IL-1ß resulted in changes in the expression at one or both time points of â¼50% of the genes probed by the arrays, the majority being down-regulated. Genes whose expression was down-regulated by IL-1ß included those encoding several collagen chains and integrin subunits. In contrast, IL-1ß induced substantial increases (>10-fold) in the expression of ICAM1, VCAM1, MMP1 and MMP3; the secretion of the encoded proteins was also markedly stimulated. IL-1ß has a pervasive effect on the expression of ECM and cell adhesion genes in human adipocytes, consistent with the derangement of tissue structure during inflammation in white fat.
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Adipocitos Blancos/metabolismo , Moléculas de Adhesión Celular/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Regulación de la Expresión Génica , Interleucina-1beta/metabolismo , Adipocitos Blancos/inmunología , Adipocitos Blancos/patología , Moléculas de Adhesión Celular/genética , Diferenciación Celular , Células Cultivadas , Proteínas de la Matriz Extracelular/genética , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/química , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Interleucina-1beta/genética , Metaloproteinasa 1 de la Matriz/química , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 3 de la Matriz/química , Metaloproteinasa 3 de la Matriz/genética , Metaloproteinasa 3 de la Matriz/metabolismo , Persona de Mediana Edad , Obesidad/inmunología , Obesidad/metabolismo , Obesidad/patología , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Grasa Subcutánea/inmunología , Grasa Subcutánea/metabolismo , Grasa Subcutánea/patología , Regulación hacia Arriba , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
BACKGROUND AND AIMS: Early detection and evaluation of vulnerable atherosclerotic plaque are important for risk stratification and timely intervention, and vascular cell adhesion molecule 1 (VCAM1) assists in adhesion and recruitment of inflammatory cells to vulnerable lesions. We labeled a single-chain variable fragment (scFv) of VCAM1 with 99mtechnetium (99mTc) and fluorescent markers to investigate its potential utility in detecting vulnerable plaques in animal models of atherosclerosis. METHODS: We labeled VCAM1 scFv with 99mTc and cyanine5 (CY5) and evaluated the probes on apolipoprotein E gene-deficient mice and New Zealand White rabbits with induced atherosclerosis. Histopathology and Western blot examinations confirmed atherosclerotic plaque and VCAM1 expression in the aortas. In vivo biodistribution of 99mTc-scFv-VCAM1 was studied. Abdominal organs of mice were removed after CY5-scFv-VCAM1 administration for aortic fluorescence imaging. Rabbits SPECT imaging of 99mTc-scFv-VCAM1 was performed and autoradiography (ARG) of the aortas was checked to confirm the tracer uptake. RESULTS: The radiochemical purity of 99mTc-scFv-VCAM1 was 98.72± 1.04% (n = 5) and its specific activity was 7.8 MBq/µg. Biodistribution study indicated predominant probe clearance by kidneys. In fluorescence imaging, stronger signal from CY5-scFv-VCAM1 in the aorta was observed in atherosclerotic mice than that in controls. SPECT imaging with 99mTc-scFv-VCAM1 showed tracer uptake in the abdominal aorta and the aortic arch of atherosclerotic animals. ARG confirmed tracer uptake in the aortas of atherosclerotic rabbits, with higher uptake ratios of aortic arch/descending aorta in experimental animals (4.45 ± 0.63, n = 5) than controls (1.12 ± 0.15, n = 5; p < 0.05). CONCLUSIONS: SPECT and fluorescence imaging results showed the feasibility and effectiveness of detecting vulnerable plaque with scFv of VCAM1, indicating its potential for early diagnosis and evaluation of atherosclerosis.
Asunto(s)
Microscopía Fluorescente , Placa Aterosclerótica/diagnóstico por imagen , Anticuerpos de Cadena Única/química , Tomografía Computarizada de Emisión de Fotón Único , Molécula 1 de Adhesión Celular Vascular/química , Animales , Aorta/diagnóstico por imagen , Aterosclerosis/diagnóstico por imagen , Ensayo de Inmunoadsorción Enzimática , Colorantes Fluorescentes/química , Humanos , Riñón/diagnóstico por imagen , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Conejos , Tecnecio/química , Distribución TisularRESUMEN
Upregulation of cell adhesion molecules on endothelial cells is a hallmark of inflammation and an early feature of several neurological conditions. Here, we describe bimodal in vivo imaging of this inflammatory event in the brain using functionalized micron-sized particles of iron oxide. The particles were conjugated to anti-VCAM-1 antibodies and subsequently labeled with iodine-125. Radiolabeling of the antibody-coated particles was straightforward and proceeded in high radiochemical yields using commercially available iodination tubes. The corresponding contrast agent was evaluated in a rat model of cerebral inflammation based on intracerebral injection of tumor necrosis factor alpha and a rat model of status epilepticus. Biodistribution studies and phosphorimaging of cryosections were used to verify in vivo imaging data obtained with single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). The contrast agent showed rapid and highly localized binding to the vasculature of inflamed brain tissue, and was effectively cleared from the blood pool within 2 min postinjection. Overall, the pattern of hypointensities observed with MRI was in good agreement with the distribution of the contrast agent as determined with SPECT and phosphorimaging; however, conspicuous differences in the signal intensities were observed. The results demonstrate that radiolabeled micron-sized particles of iron oxide enable multimodal in vivo imaging with MRI and nuclear techniques, and highlight the value of validating different imaging methods against one another.
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Medios de Contraste/farmacocinética , Inflamación/patología , Radioisótopos de Yodo/farmacocinética , Microesferas , Imagen Multimodal/métodos , Estado Epiléptico/complicaciones , Molécula 1 de Adhesión Celular Vascular/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Compuestos Férricos/metabolismo , Procesamiento de Imagen Asistido por Computador , Inflamación/etiología , Inflamación/metabolismo , Litio/toxicidad , Imagen por Resonancia Magnética/métodos , Masculino , Agonistas Muscarínicos/toxicidad , Pilocarpina/toxicidad , Radiofármacos , Ratas , Ratas Sprague-Dawley , Estado Epiléptico/inducido químicamente , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/métodos , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/inmunologíaRESUMEN
In recent years, surface modification of nanocarriers with targeting motifs has been explored to modulate delivery of various diagnostic, sensing and therapeutic molecular cargo to desired sites of interest in in vitro bioengineering platforms and in vivo pathologic tissue. However, most surface functionalization approaches are often plagued by complex chemical modifications and effortful purifications. To resolve such challenges, this study demonstrates a unique method to immobilize antibodies that can act as targeting motifs on the surfaces of nanocarriers, inspired by a process that bacteria use for immobilization of the host's antibodies. We hypothesized that alkylated Staphylococcus aureus protein A (SpA) would self-assemble with micelles and subsequently induce stable coupling of antibodies to the micelles. We examined this hypothesis by using poly(2-hydroxyethyl-co-octadecyl aspartamide) (PHEA-g-C18) as a model polymer to form micelles. The self-assembly between the micelles and alkylated SpA became more thermodynamically favorable by increasing the degree of substitution of octadecyl chains to PHEA-g-C18, due to a positive entropy change. Lastly, the mixing of SpA-PA-coupled micelles with antibodies resulted in the coating of micelles with antibodies, as confirmed with a fluorescence resonance energy transfer (FRET) assay. The micelles coated with antibodies to VCAM-1 or integrin αv displayed a higher binding affinity to substrates coated with VCAM-1 and integrin αvß3, respectively, than other controls, as evaluated with surface plasmon resonance (SPR) spectroscopy and a circulation-simulating flow chamber. We envisage that this bacteria-inspired protein immobilization approach will be useful to improve the quality of targeted delivery of nanoparticles, and can be extended to modify the surface of a wide array of nanocarriers.
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Portadores de Fármacos/química , Nanopartículas/química , Proteína Estafilocócica A/química , Secuencias de Aminoácidos , Anticuerpos/química , Biomimética , Fibroblastos/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Integrina alfaVbeta3/química , Micelas , Ácido Palmítico/química , Polímeros/química , Staphylococcus aureus , Resonancia por Plasmón de Superficie , Termodinámica , Molécula 1 de Adhesión Celular Vascular/químicaRESUMEN
Vascular inflammation plays a significant role in the pathogenesis of atherosclerosis. Luteolin, a naturally occurring flavonoid present in many medicinal plants and some commonly consumed fruits and vegetables, has received wide attention for its potential to improve vascular function in vitro. However, its effect in vivo and the molecular mechanism of luteolin at physiological concentrations remain unclear. Here, we report that luteolin as low as 0.5 µM significantly inhibited tumor necrosis factor (TNF)-α-induced adhesion of monocytes to human EA.hy 926 endothelial cells, a key event in triggering vascular inflammation. Luteolin potently suppressed TNF-α-induced expression of the chemokine monocyte chemotactic protein-1 (MCP-1) and adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), key mediators involved in enhancing endothelial cell-monocyte interaction. Furthermore, luteolin inhibited TNF-α-induced nuclear factor (NF)-κB transcriptional activity, IκBα degradation, expression of IκB kinase ß and subsequent NF-κB p65 nuclear translocation in endothelial cells, suggesting that luteolin can inhibit inflammation by suppressing NF-κB signaling. In an animal study, C57BL/6 mice were fed a diet containing 0% or 0.6% luteolin for 3 weeks, and luteolin supplementation greatly suppressed TNF-α-induced increase in circulating levels of MCP-1/JE, CXCL1/KC and sICAM-1 in C57BL/6 mice. Consistently, dietary intake of luteolin significantly reduced TNF-α-stimulated adhesion of monocytes to aortic endothelial cells ex vivo. Histology shows that luteolin treatment prevented the eruption of endothelial lining in the intima layer of the aorta and preserved elastin fibers' delicate organization as shown by Verhoeff-Van Gieson staining. Immunohistochemistry studies further show that luteolin treatment also reduced VCAM-1 and monocyte-derived F4/80-positive macrophages in the aorta of TNF-α-treated mice. In conclusion, luteolin protects against TNF-α-induced vascular inflammation in both in vitro and in vivo models. This anti-inflammatory effect of luteolin may be mediated via inhibition of the NF-κB-mediated pathway.
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Suplementos Dietéticos , Endotelio Vascular/metabolismo , Proteínas I-kappa B/antagonistas & inhibidores , Luteolina/uso terapéutico , Monocitos/inmunología , FN-kappa B/antagonistas & inhibidores , Vasculitis/dietoterapia , Animales , Antiinflamatorios no Esteroideos/metabolismo , Antiinflamatorios no Esteroideos/uso terapéutico , Aorta/inmunología , Aorta/metabolismo , Aorta/patología , Adhesión Celular , Línea Celular , Células Cultivadas , Quimiocina CCL2/antagonistas & inhibidores , Quimiocina CCL2/sangre , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/inmunología , Endotelio Vascular/patología , Células Endoteliales de la Vena Umbilical Humana/citología , Proteínas I-kappa B/metabolismo , Molécula 1 de Adhesión Intercelular/sangre , Molécula 1 de Adhesión Intercelular/química , Molécula 1 de Adhesión Intercelular/metabolismo , Luteolina/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones Endogámicos C57BL , Monocitos/metabolismo , Monocitos/patología , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Distribución Aleatoria , Transducción de Señal , Organismos Libres de Patógenos Específicos , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/metabolismo , Vasculitis/inmunología , Vasculitis/metabolismo , Vasculitis/patologíaRESUMEN
BACKGROUND AND AIM: Left ventricular (LV) hypertrophy and diastolic function have been found to be associated with obesity and hypertension in adults. However, there are scarce data about the association of obesity itself to cardiac alteration in children. The aim of this study was to detect early changes in LV structure and function in obese children and whether they are associated with the biomarkers of metabolic risk and endothelial activation. METHODS AND RESULTS: A total of 130 children aged 7-16 years (88 obese and 42 normal-weight children) were studied. All children had normal resting blood pressure. Two-dimensional ultrasound with M-mode imaging was performed to assess the LV mass index (LVMi), calculated as LV mass/height(2.7), and the peak diastolic of pulmonary venous flow velocity (PVFD). Tissue Doppler imaging was used to analyze ventricular performance through the ratio of the transmitral peak early filling velocity to the early average diastolic peak myocardial velocity (E/E'). The indicators of metabolic control, inflammation, and endothelial cell activation were evaluated. Compared to the controls, the obese subjects had significantly higher LVMi and E/E' and lower PVFD values, the two latest being found especially in severely obese subjects. In the multivariate analysis, the parameters of diastolic function (E/E' and PVFD) were independently associated with obesity, apolipoprotein A1, soluble vascular cell endothelial molecule-1 (sVCAM-1), and retinol-binding protein 4 (RBP4). CONCLUSION: An echocardiographic evaluation of diastolic function is a useful tool to detect early cardiac changes in obese children. Emergent cardiovascular risk markers such as apolipoprotein A1, RBP4, and sVCAM-1 are associated with the parameters of diastolic function.
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Enfermedades Cardiovasculares/etiología , Ventrículos Cardíacos/fisiopatología , Síndrome Metabólico/etiología , Obesidad/fisiopatología , Disfunción Ventricular Izquierda/etiología , Adolescente , Apolipoproteína A-I/sangre , Biomarcadores/sangre , Índice de Masa Corporal , Enfermedades Cardiovasculares/epidemiología , Niño , Estudios Transversales , Diagnóstico Precoz , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Síndrome Metabólico/epidemiología , Obesidad/sangre , Estudios Prospectivos , Proteínas Plasmáticas de Unión al Retinol/análisis , Factores de Riesgo , Solubilidad , España/epidemiología , Ultrasonografía , Molécula 1 de Adhesión Celular Vascular/sangre , Molécula 1 de Adhesión Celular Vascular/química , Disfunción Ventricular Izquierda/diagnóstico por imagenRESUMEN
Cowpea (Vigna unguiculata) is a drought tolerant crop with several agronomic advantages over other legumes. This study evaluated varieties from four major cowpea phenotypes (black, red, light brown and white) containing different phenolic profiles for their anti-inflammatory property on non-malignant colonic myofibroblasts (CCD18Co) cells challenged with an endotoxin (lipopolysaccharide, LPS). Intracellular reactive oxygen species (ROS) assay on the LPS-stimulated cells revealed antioxidative potential of black and red cowpea varieties. Real-time qRT-PCR analysis in LPS-stimulated cells revealed down-regulation of proinflammatory cytokines (IL-8, TNF-α, VCAM-1), transcription factor NF-κB and modulation of microRNA-126 (specific post-transcriptional regulator of VCAM-1) by cowpea polyphenolics. The ability of cowpea polyphenols to modulate miR-126 signaling and its target gene VCAM-1 were studied in LPS-stimulated endothelial cells transfected with a specific inhibitor of miR-126, and treated with 10 mg GAE/L black cowpea extract where the extract in part reversed the effect of the miR-126 inhibitor. This suggests that cowpea may exert their anti-inflammatory activities at least in part through induction of miR-126 that then down-regulate VCAM-1 mRNA and protein expressions. Overall, Cowpea therefore is promising as an anti-inflammatory dietary component.
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Antiinflamatorios no Esteroideos/metabolismo , Colitis/prevención & control , Fabaceae/química , Alimentos Funcionales/análisis , Extractos Vegetales/metabolismo , Polifenoles/metabolismo , Semillas/química , Antiinflamatorios no Esteroideos/análisis , Antiinflamatorios no Esteroideos/química , Antioxidantes/análisis , Antioxidantes/química , Antioxidantes/metabolismo , Línea Celular , Colitis/inmunología , Colitis/metabolismo , Colon/inmunología , Colon/metabolismo , Citocinas/antagonistas & inhibidores , Citocinas/genética , Citocinas/metabolismo , Regulación hacia Abajo , Fabaceae/metabolismo , Humanos , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , MicroARNs/metabolismo , Miofibroblastos/inmunología , Miofibroblastos/metabolismo , Pigmentos Biológicos/biosíntesis , Extractos Vegetales/química , Polifenoles/análisis , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Semillas/metabolismo , Especificidad de la Especie , Texas , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Escin, a natural mixture of triterpenoid saponin isolated from the seed of the horse chestnut, is reported to have a potent antiulcer activity against ethanol-induced gastric mucosal lesions. This study investigated the possible mechanisms underlying the gastroprotective effect of escin against indomethacin-induced gastric ulcer in mice. Gastric ulceration was induced by a single intragastric administration of indomethacin (18 mg/kg). The mice underwent intragastric treatment with escin at doses of 0.45, 0.9 or 1.8 mg/kg. Gastric lesion was estimated morphometrically and histopathologically 6 h after the indomethacin administration. The antioxidative parameters in gastric mucosa were measured. Moreover, the activity of myeloperoxidase and the contents of TNF-α, P-selectin and VCAM-1 in gastric tissues were determined. The results showed that escin protected gastric tissues against indomethacin-induced gastropathy as demonstrated from a reduction in the ulcer index and an attenuation of histopathologic changes. Escin caused significant reductions of the contents of malondialdehyde, TNF-α, P-selectin, VCAM-1 and myeloperoxidase activity. The altered activities of superoxide dismutase, catalase and glutathione peroxidase in the stomach tissues were also ameliorated by escin treatment. The present study demonstrated that escin had a protective effect against indomethacin-induced gastric ulcer in mice, not only by virtue of its antioxidant potential, but also due to its anti-inflammatory effect.
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Antiinflamatorios no Esteroideos/antagonistas & inhibidores , Antiulcerosos/uso terapéutico , Escina/uso terapéutico , Mucosa Gástrica/efectos de los fármacos , Indometacina/antagonistas & inhibidores , Sustancias Protectoras/uso terapéutico , Úlcera Gástrica/prevención & control , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Antiulcerosos/administración & dosificación , Antioxidantes/administración & dosificación , Antioxidantes/uso terapéutico , Relación Dosis-Respuesta a Droga , Escina/administración & dosificación , Mucosa Gástrica/inmunología , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , ATPasa Intercambiadora de Hidrógeno-Potásio/química , ATPasa Intercambiadora de Hidrógeno-Potásio/metabolismo , Indometacina/efectos adversos , Peroxidación de Lípido/efectos de los fármacos , Ratones , Oxidorreductasas/antagonistas & inhibidores , Oxidorreductasas/metabolismo , Selectina-P/antagonistas & inhibidores , Selectina-P/química , Selectina-P/metabolismo , Sustancias Protectoras/administración & dosificación , Distribución Aleatoria , Índice de Severidad de la Enfermedad , Estómago/efectos de los fármacos , Estómago/inmunología , Estómago/patología , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patología , Factor de Necrosis Tumoral alfa/agonistas , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/química , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
UNLABELLED: (99m)Tc-cAbVCAM1-5, a single-domain antibody fragment directed against mouse or human vascular cell adhesion molecule 1 (VCAM-1), recently has been proposed as a new imaging agent for the detection of inflamed atherosclerotic lesions. Indeed, in a mouse model of atherosclerosis, (99m)Tc-cAbVCAM1-5 specifically bound to VCAM-1-positive lesions, thereby allowing their identification on SPECT images. The purpose of the present study was to investigate (99m)Tc-cAbVCAM1-5 imaging sensitivity using a reference statin therapy. METHODS: Thirty apolipoprotein E-deficient mice were fed a western-type diet. First, the relationship between the level of VCAM-1 expression and (99m)Tc-cAbVCAM1-5 uptake was evaluated in 18 mice using immunohistochemistry and autoradiography. Second, longitudinal SPECT/CT imaging was performed on control (n = 9) or atorvastatin-treated mice (0.01% w/w, n = 9). RESULTS: (99m)Tc-cAbVCAM1-5 uptake in atherosclerotic lesions correlated with the level of VCAM-1 expression (P < 0.05). Atorvastatin exerted significant antiatherogenic effects, and (99m)Tc-cAbVCAM1-5 lesion uptake was significantly reduced in 35-wk-old atorvastatin-treated mice, as indicated by ex vivo γ-well counting and autoradiography (P < 0.05). SPECT imaging quantification based on contrast-enhanced CT was reproducible (interexperimenter intraclass correlation coefficient, 0.97; intraexperimenter intraclass correlation coefficient, 0.90), and yielded results that were highly correlated with tracer biodistribution (r = 0.83; P < 0.0001). Therefore, reduced (99m)Tc-cAbVCAM1-5 uptake in atorvastatin-treated mice was successfully monitored noninvasively by SPECT/CT imaging (0.87 ± 0.06 vs. 1.11 ± 0.09 percentage injected dose per cubic centimeter in control group, P < 0.05). CONCLUSION: (99m)Tc-cAbVCAM1-5 imaging allowed the specific, sensitive, and reproducible quantification of VCAM-1 expression in mouse atherosclerotic lesions. (99m)Tc-cAbVCAM1-5 therefore exhibits suitable characteristics for the evaluation of novel antiatherogenic agents.