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1.
Clin Exp Immunol ; 199(3): 303-313, 2020 03.
Article in English | MEDLINE | ID: mdl-31758701

ABSTRACT

Kawasaki disease (KD) is the leading cause of acquired heart disease in children. In addition to coronary artery abnormalities, aneurysms and myocarditis, acute KD is also associated with echocardiogram (ECG) abnormalities in 40-80% of patients. Here, we show that these ECG changes are recapitulated in the Lactobacillus casei cell wall extract (LCWE)-induced KD vasculitis mouse model. LCWE-injected mice developed elevated heart rate and decreased R wave amplitude, with significant differences in prolonged ventricular repolarization. LCWE-injected mice developed cardiac ganglion inflammation, that may affect the impulse-conducting system in the myocardium. Furthermore, serum nerve growth factor (NGF) was significantly elevated in LCWE-injected mice, similar to children with KD vasculitis, associated with increased neural remodeling of the myocardium. ECG abnormalities were prevented by blocking interleukin (IL)-1 signaling with anakinra, and the increase in serum NGF and cardiac neural remodeling were similarly blocked in Il1r1-/- mice and in wild-type mice treated with anakinra. Thus, similar to clinical KD, the LCWE-induced KD vasculitis mouse model also exhibits electrophysiological abnormalities and cardiac neuronal remodeling, and these changes can be prevented by blocking IL-1 signaling. These data support the acceleration of anti-IL-1 therapy trials to benefit KD patients.


Subject(s)
Disease Models, Animal , Interleukin-1/metabolism , Mucocutaneous Lymph Node Syndrome/physiopathology , Vasculitis/physiopathology , Animals , Antirheumatic Agents/pharmacology , Biological Products/toxicity , Cell Wall/chemistry , Child , Electrocardiography/drug effects , Female , Humans , Interleukin 1 Receptor Antagonist Protein/pharmacology , Interleukin-1/genetics , Lacticaseibacillus casei/chemistry , Mice, Inbred C57BL , Mice, Knockout , Mucocutaneous Lymph Node Syndrome/chemically induced , Mucocutaneous Lymph Node Syndrome/therapy , Nerve Growth Factor/blood , Receptors, Interleukin-1 Type I/genetics , Receptors, Interleukin-1 Type I/metabolism , Signal Transduction/drug effects , Vasculitis/chemically induced , Vasculitis/therapy
2.
Am J Transplant ; 16(2): 640-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26461171

ABSTRACT

Primary graft dysfunction (PGD) is a possible risk factor for bronchiolitis obliterans syndrome (BOS) following lung transplantation; however, the mechanism for any such association is poorly understood. Based on the association of TGF-ß with acute and chronic inflammatory disorders, we hypothesized that it might play a role in the continuum between PGD and BOS. Thus, the association between PGD and BOS was assessed in a single-center cohort of lung transplant recipients. Bronchoalveolar lavage fluid concentrations of TGF-ß and procollagen collected within 24 h of transplantation were compared across the spectrum of PGD, and incorporated into Cox models of BOS. Immunohistochemistry localized expression of TGF-ß and its receptor in early lung biopsies posttransplant. We found an association between PGD and BOS in both bilateral and single lung recipients with a hazard ratio of 3.07 (95% CI 1.76-5.38) for the most severe form of PGD. TGF-ß and procollagen concentrations were elevated during PGD (p < 0.01), and associated with increased rates of BOS. Expression of TGF-ß and its receptor localized to allograft infiltrating mononuclear and stromal cells, and the airway epithelium. These findings validate the association between PGD and the subsequent development of BOS, and suggest that this association may be mediated by receptor/TGF-ß biology.


Subject(s)
Biomarkers/metabolism , Bronchiolitis Obliterans/diagnosis , Graft Rejection/diagnosis , Lung Transplantation/adverse effects , Primary Graft Dysfunction/diagnosis , Transforming Growth Factor beta/metabolism , Aged , Bronchiolitis Obliterans/etiology , Bronchiolitis Obliterans/metabolism , Case-Control Studies , Female , Follow-Up Studies , Graft Rejection/blood , Graft Rejection/etiology , Graft Survival , Humans , Immunoenzyme Techniques , Lung Diseases/surgery , Male , Middle Aged , Postoperative Complications , Primary Graft Dysfunction/etiology , Primary Graft Dysfunction/metabolism , Prognosis , Prospective Studies , Retrospective Studies , Risk Assessment , Risk Factors , Severity of Illness Index
3.
Am J Transplant ; 15(8): 2037-49, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25904443

ABSTRACT

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro.


Subject(s)
Antibodies, Monoclonal/immunology , Complement Activation/immunology , Complement C1s/immunology , HLA Antigens/immunology , Cells, Cultured , Endothelium, Vascular/cytology , Endothelium, Vascular/immunology , Heart Transplantation , Humans
4.
Lung ; 192(3): 421-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24682307

ABSTRACT

Hepatopulmonary syndrome (HPS) is characterized by impaired oxygenation due to pulmonary vascular dilatation in patients with end-stage liver disease. At our center, we identified 29 patients who were listed for liver transplantation (LT) with a model for end-stage liver disease exception for HPS between 2001 and 2012. Five of these patients were found to have concurrent interstitial lung disease (ILD). The chest high-resolution computed-tomography demonstrated ground-glass opacities and subpleural reticulation, most consistent with nonspecific interstitial pneumonia (NSIP). All four of our patients who underwent LT experienced prolonged hypoxemia postoperatively, with one surgery-related death. However, the three surviving patients had eventual resolution of their hypoxemia with no evidence of ILD progression. In conclusion, we report a high prevalence of ILD, most consistent with NSIP, among patients with HPS. Although there may be increased perioperative risks, the finding of ILD in patients with HPS should not be considered an absolute contraindication to LT.


Subject(s)
Hepatopulmonary Syndrome/complications , Lung Diseases, Interstitial/complications , Adult , Aged , Biopsy , California , Fatal Outcome , Female , Hepatopulmonary Syndrome/diagnosis , Hepatopulmonary Syndrome/surgery , Humans , Hypoxia/diagnosis , Hypoxia/etiology , Liver Transplantation/adverse effects , Lung Diseases, Interstitial/diagnostic imaging , Male , Middle Aged , Patient Selection , Risk Assessment , Risk Factors , Tomography, X-Ray Computed , Treatment Outcome , Waiting Lists
5.
Am J Transplant ; 13(2): 299-311, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23279566

ABSTRACT

Donor-specific HLA antibodies significantly lower allograft survival, but as yet there are no satisfactory therapies for prevention of antibody-mediated rejection. Intracapillary macrophage infiltration is a hallmark of antibody-mediated rejection, and macrophages are important in both acute and chronic rejection. The purpose of this study was to investigate the Fc-independent effect of HLA I antibodies on endothelial cell activation, leading to monocyte recruitment. We used an in vitro model to assess monocyte binding to endothelial cells in response to HLA I antibodies. We confirmed our results in a mouse model of antibody-mediated rejection, in which B6.RAG1(-/-) recipients of BALB/c cardiac allografts were passively transferred with donor-specific MHC I antibodies. Our findings demonstrate that HLA I antibodies rapidly increase intracellular calcium and endothelial presentation of P-selectin, which supports monocyte binding. In the experimental model, donor-specific MHC I antibodies significantly increased macrophage accumulation in the allograft. Concurrent administration of rPSGL-1-Ig abolished antibody-induced monocyte infiltration in the allograft, but had little effect on antibody-induced endothelial injury. Our data suggest that antagonism of P-selectin may ameliorate accumulation of macrophages in the allograft during antibody-mediated rejection.


Subject(s)
Antibodies/immunology , Graft Rejection/immunology , Histocompatibility Antigens Class I/immunology , Monocytes/cytology , P-Selectin/antagonists & inhibitors , Animals , Antibodies, Monoclonal/chemistry , Aorta/cytology , Calcium/metabolism , Cells, Cultured , Endothelial Cells/cytology , Exocytosis , Heart Transplantation/methods , Humans , Immunization, Passive , Leukocyte Common Antigens/metabolism , Macrophages/cytology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Transplantation, Homologous/immunology
6.
Am J Transplant ; 12(2): 477-84, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22152000

ABSTRACT

Community-acquired respiratory viruses (CARV) can accelerate the development of lung allograft dysfunction, but the immunologic mechanisms are poorly understood. The chemokine receptor CXCR3 and its chemokine ligands, CXCL9, CXCL10 and CXCL11 have roles in the immune response to viruses and in the pathogenesis of bronchiolitis obliterans syndrome, the predominant manifestation of chronic lung allograft rejection. We explored the impact of CARV infection on CXCR3/ligand biology and explored the use of CXCR3 chemokines as biomarkers for subsequent lung allograft dysfunction. Seventeen lung transplant recipients with CARV infection had bronchoalveolar lavage fluid (BALF) available for analysis. For comparison, we included 34 BALF specimens (2 for each CARV case) that were negative for infection and collected at a duration posttransplant similar to a CARV case. The concentration of each CXCR3 chemokine was increased during CARV infection. Among CARV infected patients, a high BALF concentration of either CXCL10 or CXCL11 was predictive of a greater decline in forced expiratory volume in 1 s, 6 months later. CXCR3 chemokine concentrations provide prognostic information and this may have important implications for the development of novel treatment strategies to modify outcomes after CARV infection.


Subject(s)
Graft Rejection/etiology , Lung Transplantation , Receptors, CXCR3/metabolism , Respiratory Tract Infections/complications , Virus Diseases/complications , Biomarkers/metabolism , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/virology , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Graft Rejection/immunology , Graft Rejection/metabolism , Humans , Immunohistochemistry , Ligands , Male , Middle Aged , Prognosis , Prospective Studies , Respiratory Tract Infections/metabolism , Respiratory Tract Infections/virology , Risk Factors , Transplantation, Homologous , Virus Diseases/metabolism , Virus Diseases/virology , Viruses/isolation & purification
7.
Eur Respir J ; 36(4): 893-900, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20351032

ABSTRACT

Lung involvement is the leading cause of death in systemic sclerosis (SSc), but lung transplantation (LT) for systemic disease remains controversial. Our objective was to comprehensively evaluate post-LT outcomes for SSc compared to idiopathic pulmonary fibrosis (IPF). We retrospectively evaluated bilateral LT recipients (LTRs) with SSc or IPF at our centre between January 1, 2003 and December 31, 2007. The primary end-point was all-cause mortality at 1 yr post-LT. Secondary end-points included assessments of acute rejection (AR), pulmonary function, infection and chronic rejection. 14 patients with SSc and 38 patients with IPF underwent LT. Apart from a younger SSc cohort (53.2 versus 58.8 yrs; p = 0.02), the two groups were well matched. 1-yr all-cause mortality was no different between SSc (6.6%) and IPF (13.1%) groups, after adjusting for age (p = 0.62). Rates of (AR) ≥2 were significantly increased for the SSc compared with the IPF group (hazard ratio (HR) 2.91; p = 0.007). Other end-points, including chronic rejection, infection and pulmonary function, showed no differences. SSc LTRs experience similar survival 1 yr post-LT when compared to IPF. AR rates may be significantly higher in the SSc group. Longer follow-up is necessary to determine the effects of gastrointestinal dysfunction and AR on late allograft function in SSc LTR.


Subject(s)
Lung Transplantation/methods , Scleroderma, Systemic/therapy , Adult , Algorithms , Cohort Studies , Female , Humans , Immunosuppressive Agents/pharmacology , Male , Middle Aged , Patient Compliance , Pulmonary Fibrosis/complications , Pulmonary Fibrosis/therapy , Retrospective Studies , Scleroderma, Systemic/complications , Time Factors , Treatment Outcome
8.
Am J Transplant ; 9(8): 1903-11, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19459819

ABSTRACT

Multiple infections have been linked with the development of bronchiolitis obliterans syndrome (BOS) post-lung transplantation. Lung allograft airway colonization by Aspergillus species is common among lung transplant recipients. We hypothesized that Aspergillus colonization may promote the development of BOS and may decrease survival post-lung transplantation. We reviewed all lung transplant recipients transplanted in our center between January 2000 and June 2006. Bronchoscopy was performed according to a surveillance protocol and when clinically indicated. Aspergillus colonization was defined as a positive culture from bronchoalveolar lavage or two sputum cultures positive for the same Aspergillus species, in the absence of invasive pulmonary Aspergillosis. We found that Aspergillus colonization was strongly associated with BOS and BOS related mortality in Cox regression analyses. Aspergillus colonization typically preceded the development of BOS by a median of 261 days (95% CI 87-520). Furthermore, in a multivariate Cox regression model, Aspergillus colonization was a distinct risk factor for BOS, independent of acute rejection. These data suggest a potential causative role for Aspergillus colonization in the development of BOS post-lung transplantation and raise the possibility that strategies aimed to prevent Aspergillus colonization may help delay or reduce the incidence of BOS.


Subject(s)
Aspergillosis/complications , Aspergillus/pathogenicity , Bronchiolitis Obliterans/epidemiology , Lung Transplantation/adverse effects , Lung/microbiology , Adolescent , Adult , Aged , Antifungal Agents/therapeutic use , Aspergillosis/prevention & control , Female , Humans , Incidence , Kaplan-Meier Estimate , Lung Transplantation/immunology , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors , Transplantation, Homologous , Young Adult
9.
Am J Transplant ; 8(9): 1921-30, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18671677

ABSTRACT

Pathologic obliterative bronchiolitis (OB)/Bronchiolitis obliterans syndrome (pathologic OB/BOS) is the major obstacle to long-term survival post-lung transplantation (LT). Our group has demonstrated that pulmonary hypertension (PH) complicates the course of chronic inflammatory lung diseases that have similarities to pathologic OB/BOS and that vascular remodeling of the bronchial circulation occurs during BOS. Consequently, we hypothesized that PH is associated with pathologic OB/BOS and may result from a vasculopathy of the allograft pulmonary circulation. We conducted a single-center, retrospective study and examined the presence of PH and vasculopathy in patients with pathologic OB/BOS. Fifty-two pathologic specimens post-LT were recovered from January 10, 1997 to January 5, 2007 and divided into two groups, those with and without pathologic OB/BOS.PH was defined as a mean pulmonary artery pressure (mPAP) > 25 mmHg by right heart catheterization (RHC) or right ventricular systolic pressure (RVSP) > or = 45 mmHg by transthoracic echocardiogram (TTE). PH was more prevalent in those LT recipients with pathologic OB/BOS (72% vs. 0%, p = 0.003). Furthermore, pulmonary arteriopathy and venopathy were more prevalent in patients with pathologic OB/BOS (84% vs. 4%, p < 0.0001, and 77% vs. 35%, p = 0.004, respectively). PH is common in LT recipients with pathologic OB/BOS and is associated with a vasculopathy of the allograft pulmonary circulation.


Subject(s)
Blood Vessels/pathology , Bronchiolitis Obliterans/pathology , Bronchiolitis Obliterans/physiopathology , Hypertension, Pulmonary/complications , Lung Transplantation/adverse effects , Adult , Blood Vessels/physiopathology , Female , Humans , Hypertension, Pulmonary/physiopathology , Male , Middle Aged , Retrospective Studies , Transplantation, Homologous/adverse effects , Transplants/adverse effects
10.
Am J Transplant ; 8(7): 1512-22, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18513272

ABSTRACT

Pulmonary CMV infection (CMVI) and disease (CMVD) is associated with reduced long-term survival post-lung transplantation, however, the specific biologic mechanisms remain unclear. We have demonstrated a role of CC chemokines during lung allograft dysfunction. Based on these findings, we hypothesized that pulmonary CMV upregulates the expression of multiple CC chemokines that leads to allograft dysfunction and decreased long-term survival. We performed a nested case control study in lung transplant recipients to investigate alterations in CC chemokine biology during pulmonary CMV. Levels of CC chemokines were measured in bronchoalveolar lavage fluid (BALF) from recipients with CMVI (n = 33), CMVD (n = 6), and in healthy lung transplant controls (n = 33). We found a trend toward increased levels of MIP-1alpha/CCL3 during pulmonary CMVI. Levels of MCP-1/CCL2 and RANTES/CCL5 were significantly elevated during pulmonary CMV. Interestingly, elevated levels of CCL3 in BALF were protective with regards to survival. Importantly, elevated levels of CCL2 in BALF predicted the development of BOS, while elevated levels of CCL5 in BALF predicted an increase in mortality post-lung transplant. Altered levels of specific CC chemokines during pulmonary CMV are associated with future clinical outcomes. These results suggest a possible utility of BALF CC chemokines as biomarkers for guiding risk assessment during pulmonary CMV post-lung transplantation.


Subject(s)
Bronchiolitis Obliterans/blood , Bronchiolitis Obliterans/mortality , Chemokines, CC/blood , Cytomegalovirus Infections/blood , Lung Transplantation/mortality , Bronchiolitis Obliterans/virology , Bronchoalveolar Lavage Fluid/virology , Case-Control Studies , Chemokine CCL2/blood , Chemokine CCL3/blood , Cytomegalovirus Infections/mortality , Female , Graft Survival , Humans , Male , Middle Aged , Receptors, Chemokine/blood , Risk Assessment , Up-Regulation
11.
Methods Inf Med ; 46(2): 206-11, 2007.
Article in English | MEDLINE | ID: mdl-17347757

ABSTRACT

OBJECTIVES: A new deconvolution method for the analysis of time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) data is introduced and applied for tissue diagnosis. METHOD: The intrinsic TR-LIFS decays are expanded on a Laguerre basis, and the computed Laguerre expansion coefficients (LEC) are used to characterize the sample fluorescence emission. The method was applied for the diagnosis of atherosclerotic vulnerable plaques. RESULTS: At a first stage, using a rabbit atherosclerotic model, 73 TR-LIFS in-vivo measurements from the normal and atherosclerotic aorta segments of eight rabbits were taken. The Laguerre deconvolution technique was able to accurately deconvolve the TR-LIFS measurements. More interesting, the LEC reflected the changes in the arterial biochemical composition and provided discrimination of lesions rich in macrophages/foam-cells with high sensitivity (> 85%) and specificity (> 95%). At a second stage, 348 TR-LIFS measurements were obtained from the explanted carotid arteries of 30 patients. Lesions with significant inflammatory cells (macrophages/foam-cells and lymphocytes) were detected with high sensitivity (> 80%) and specificity (> 90%), using LEC-based classifiers. CONCLUSION: This study has demonstrated the potential of using TR-LIFS information by means of LEC for in vivo tissue diagnosis, and specifically for detecting inflammation in atherosclerotic lesions, a key marker of plaque vulnerability.


Subject(s)
Arteriosclerosis/diagnosis , Lasers , Signal Processing, Computer-Assisted , Spectrometry, Fluorescence , Spectrum Analysis/instrumentation , Animals , Arteriosclerosis/pathology , Computer Systems , Foam Cells , Humans , Inflammation , Macrophages , Rabbits , Spectrum Analysis/methods , Time
12.
Transplant Proc ; 38(10): 3221-4, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17175228

ABSTRACT

UNLABELLED: Chemokines are known to participate in allograft rejection by mediating leukocyte trafficking. Despite redundancy in chemokine family, several chemokine-chemokine receptor interactions have proven critical in alloimmune responses. We sought to determine the effect of combined blockade of CXCR3 and CCR5, two critical chemokine receptors, in acute rejection. METHODS: Heterotopic heart transplantation was performed using BALB/c to B6/129 mice deficient in CCR5. Following transplantation these mice were treated with goat anti-CXCR3 serum every other day. In the control group, BALB/c hearts were transplanted in wild type B6/129 recipients and treated with goat serum alone. No immunosuppression was given to either group. Recipient mice were then assessed daily for allograft function by abdominal palpation, and graft survival was confirmed by laparotomy. RESULTS: The donor hearts in the control group were rejected at 6 +/- 1 days posttransplantation. Combined blockade of CXCR3 and CCR5 prolonged allograft survival versus control; all allografts survived to 24 days. In addition, there was a decrease in graft infiltrating CD4 and CD8 lymphocytes in the experimental group at 24 days. CONCLUSION: Combined CXCR3 and CCR5 blockade is effective in prolonging allograft survival in a fully MHC mismatched murine model. Combined chemokine blockade holds promise in control of acute rejection in organ transplantation.


Subject(s)
CCR5 Receptor Antagonists , Graft Rejection/immunology , Graft Survival/immunology , Heart Transplantation/immunology , Receptors, Chemokine/antagonists & inhibitors , Transplantation, Homologous/immunology , Animals , Mice , Mice, Inbred BALB C , Mice, Knockout , Receptors, CCR5/deficiency , Receptors, CCR5/immunology , Receptors, CXCR3 , Receptors, Chemokine/immunology
13.
Transplant Proc ; 38(10): 3259-62, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17175242

ABSTRACT

Chronic rejection in transplanted hearts or cardiac allograft vasculopathy (CAV) is the leading cause of late death among heart transplant recipients. We hypothesized that induction of HO-1 by D4-F, an apoA-I mimetic peptide with potent antiinflammatory/antioxidant properties, attenuated CAV. We utilized a previously characterized murine model of CAV. B6.C-H2(bml2) hearts were heterotopically transplanted into C57BL/6 mice. In the control group, recipient mice were treated with 20 microg of saline daily. In experimental group I, mice were treated daily with 20 microg of D4-F. In experimental group II, mice were treated daily with 20 microg of D4-F daily, plus CuPP, which does not have any effect on HO-1 activity. In experimental group III, recipient mice were treated with 20 mug of D4-F daily, plus SnPP, which is a competitive inhibitor of HO-1. Donor hearts were harvested on day 24 after transplantation. The donor hearts in the control group developed severe intimal lesions. In experimental group I, treatment with D4-F was associated with upregulation of HO-1 and a marked reduction in intimal lesions, which was consistent in experimental group II. In experimental group III, inhibition of HO-1 was associated with partial restoration of intimal lesions. Induction of HO-1 by an apoA-1 mimetic peptide was effective to control CAV. This class of antiinflammatory peptides, which show an ability to induce HO-1, provides a novel strategy for the treatment of CAV.


Subject(s)
Graft Rejection/prevention & control , Heart Transplantation/immunology , Heme Oxygenase-1/genetics , Animals , Anti-Inflammatory Agents/pharmacology , Apolipoprotein A-I/pharmacology , Female , Heart Transplantation/pathology , Mice , Mice, Inbred C57BL , Models, Animal , Peptide Fragments/pharmacology , Transplantation, Heterotopic , Transplantation, Homologous/immunology , Transplantation, Homologous/pathology
14.
Am J Transplant ; 6(7): 1560-71, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16827856

ABSTRACT

We tested the hypothesis that phosphorylation of S6 ribosomal protein (S6RP), a downstream target of the PI3K/Akt/mTOR pathway, is a biomarker of antibody-mediated rejection (AMR) in heart allografts. Primary cultures of human aortic and microvascular endothelial cells (EC) were treated with anti-HLA class I and class II antibodies (Ab) and cell lysates were studied for phosphorylation of S6 ribosmal protein at Serine235/236 (p-S6RP). Treatment of cultured EC with anti-class I and class II Ab stimulated S6RP phosphorylation. Immunohistochemical techniques were used to detect the level of p-S6RP in endomyocardial biopsies (n = 131) from 46 heart transplant recipients and the results were correlated with histopathological diagnosis of rejection, C4d staining, production of posttransplant anti-HLA Ab and clinical outcome. Increased phosphorylation of S6RP in endomyocardial biopsies was significantly associated with the diagnosis of AMR (p < 0.0001). No significant association between acute cellular rejection (ACR) and p-S6RP was observed. C4d staining was positively associated with both AMR and p-S6RP. Posttransplant anti-HLA class II Ab production was also significantly associated with a positive p-S6RP status in cardiac biopsies. These results indicate that p-S6RP is a useful biomarker for the diagnosis of AMR.


Subject(s)
Antibodies/immunology , Graft Rejection/immunology , Heart Transplantation , Ribosomal Protein S6/metabolism , Acute Disease , Biomarkers , Biopsy , Cells, Cultured , Endothelial Cells/immunology , Endothelial Cells/metabolism , Graft Rejection/enzymology , Heart Transplantation/immunology , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class II/immunology , Humans , Myocardium/metabolism , Phosphorylation , Protein Kinases/metabolism , Signal Transduction , Transplantation, Homologous/immunology
15.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 2663-6, 2006.
Article in English | MEDLINE | ID: mdl-17946129

ABSTRACT

In this study, time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) and ultrasonography were applied to detect vulnerable (high-risk) atherosclerotic plaque. A total of 813 TR-LIFS measurements were taken from carotid plaques of 65 patients, and subsequently analyzed using the Laguerre deconvolution technique. The investigated spots were classified by histopathology as thin, fibrotic, calcified, low-inflamed, inflamed and necrotic lesions. Spectral and time-resolved parameters (normalized intensity values and Laguerre expansion coefficients) were extracted from the TR-LIFS data. Feature selection for classification was performed by either analysis of variance (ANOVA) or principal component analysis (PCA). A stepwise linear discriminant analysis algorithm was developed for detecting inflamed and necrotic lesion, representing the most vulnerable plaques. These vulnerable plaques were detected with high sensitivity (>80%) and specificity (>90%). Ultrasound (US) imaging was obtained in 4 carotid plaques in addition to TR-LIFS examination. Preliminary results indicate that US provides important structural information of the plaques that could be combined with the compositional information obtained by TR-LIFS, to obtain a more accurate diagnosis of vulnerable atherosclerotic plaque.


Subject(s)
Algorithms , Carotid Artery Diseases/diagnosis , Diagnosis, Computer-Assisted/methods , Spectrometry, Fluorescence/methods , Ultrasonography/methods , Humans , Reproducibility of Results , Sensitivity and Specificity
16.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 6559-62, 2005.
Article in English | MEDLINE | ID: mdl-17281773

ABSTRACT

This study investigates the ability of time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) to detect inflammation in atherosclerotic lesion, a key feature of plaque vulnerability. A total of 348 TR-LIFS measurements were taken from carotid plaques of 30 patients, and subsequently analyzed using the Laguerre deconvolution technique. The investigated spots were classified as Early, Fibrotic/Calcified or Inflamed lesions. A stepwise linear discriminant analysis algorithm was developed using spectral and TR features (normalized intensity values and Laguerre expansion coefficients at discrete emission wavelengths, respectively). Features from only three emission wavelengths (390, 450 and 500 nm) were used in the classifier. The Inflamed lesions were discriminated with sensitivity > 80% and specificity > 90 %, when the Laguerre expansion coefficients were included in the feature space. These results indicate that TR-LIFS information derived from the Laguerre expansion coefficients at few selected emission wavelengths can discriminate inflammation in atherosclerotic plaques. We believe that TR-LIFS derived Laguerre expansion coefficients can provide a valuable additional dimension for the detection of vulnerable plaques.

17.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 1372-5, 2004.
Article in English | MEDLINE | ID: mdl-17271948

ABSTRACT

This study investigates the ability of new analytical methods of time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) data to characterize tissue in-vivo, such as the composition of atherosclerotic vulnerable plaques. A total of 73 TR-LIFS measurements were taken in-vivo from the aorta of 8 rabbits, and subsequently analyzed using the Laguerre deconvolution technique. The investigated spots were classified as normal aorta, thin or thick lesions, and lesions rich in either collagen or macrophages/foam-cells. Different linear and nonlinear classification algorithms (linear discriminant analysis, stepwise linear discriminant analysis, principal component analysis, and feedforward neural networks) were developed using spectral and TR features (ratios of intensity values and Laguerre expansion coefficients, respectively). Normal intima and thin lesions were discriminated from thick lesions (sensitivity >90%, specificity 100%) using only spectral features. However, both spectral and time-resolved features were necessary to discriminate thick lesions rich in collagen from thick lesions rich in foam cells (sensitivity >85%, specificity >93%), and thin lesions rich in foam cells from normal aorta and thin lesions rich in collagen (sensitivity >85%, specificity >94%). Based on these findings, we believe that TR-LIFS information derived from the Laguerre expansion coefficients can provide a valuable additional dimension for in-vivo tissue characterization.

18.
Circulation ; 104(25): 3103-8, 2001 Dec 18.
Article in English | MEDLINE | ID: mdl-11748108

ABSTRACT

BACKGROUND: Inflammation is implicated in atherogenesis and plaque disruption. Toll-like receptor 2 (TLR-2) and TLR-4, a human homologue of drosophila Toll, play an important role in the innate and inflammatory signaling responses to microbial agents. To investigate a potential role of these receptors in atherosclerosis, we assessed the expression of TLR-2 and TLR-4 in murine and human atherosclerotic plaques. METHODS AND RESULTS: Aortic root lesions of high-fat diet-fed apoE-deficient mice (n=5) and human coronary atherosclerotic plaques (n=9) obtained at autopsy were examined for TLR-4 and TLR-2 expression by immunohistochemistry. Aortic atherosclerotic lesions in all apoE-deficient mice expressed TLR-4, whereas aortic tissue obtained from control C57BL/6J mice showed no TLR-4 expression. All 5 lipid-rich human plaques expressed TRL-4, whereas the 4 fibrous plaques and 4 normal human arteries showed no or minimal expression. Serial sections and double immunostaining showed TLR-4 colocalizing with macrophages both in murine atherosclerotic lesions and at the shoulder region of human coronary artery plaques. In contrast to TLR-4, none of the plaques expressed TLR-2. Furthermore, basal TLR-4 mRNA expression by human monocyte-derived macrophages was upregulated by ox-LDL in vitro. CONCLUSIONS: Our study demonstrates that TLR-4 is preferentially expressed by macrophages in murine and human lipid-rich atherosclerotic lesions, where it may play a role to enhance and sustain the innate immune and inflammatory responses. Moreover, upregulation of TLR-4 in macrophages by oxidized LDL suggests that TLR-4 may provide a potential pathophysiological link between lipids and infection/inflammation and atherosclerosis.


Subject(s)
Arteriosclerosis/metabolism , Drosophila Proteins , Lipid Metabolism , Lipoproteins, LDL/pharmacology , Macrophages/drug effects , Membrane Glycoproteins/drug effects , Receptors, Cell Surface/drug effects , Animals , Apolipoproteins E/deficiency , Apolipoproteins E/genetics , Arteriosclerosis/pathology , Coronary Vessels/chemistry , Coronary Vessels/pathology , Gene Expression Regulation/drug effects , Humans , Immunohistochemistry , Macrophages/metabolism , Macrophages/pathology , Membrane Glycoproteins/biosynthesis , Membrane Glycoproteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Cell Surface/biosynthesis , Receptors, Cell Surface/genetics , Reverse Transcriptase Polymerase Chain Reaction , Toll-Like Receptor 2 , Toll-Like Receptor 4 , Toll-Like Receptors
19.
Circ Res ; 89(12): 1122-9, 2001 Dec 07.
Article in English | MEDLINE | ID: mdl-11739276

ABSTRACT

c-Myc, a protooncogene, mediates both proliferative and cellular growth in many cell types. Although not expressed in the adult heart under normal physiological conditions, Myc expression is rapidly upregulated in response to hypertrophic stimuli. Although Myc is capable of sustaining hyperplastic growth in fetal myocytes, the effects of its re-expression in adult postmitotic myocardium and its role in mediating cardiac hypertrophy are unknown. To determine the effects of de novo Myc activity in adult postmitotic myocardium in vivo, we created a novel transgenic model in which Myc is expressed and inducibly activated specifically in cardiac myocytes. Activation of Myc in adult myocardium was sufficient to reproduce the characteristic changes in myocyte size, protein synthesis, and cardiac-specific gene expression seen in cardiac hypertrophy. Despite the increased cardiac mass, left ventricular function remained normal. Activation of Myc also provoked cell cycle reentry in postmitotic myocytes, which led to increased nuclei per myocyte and DNA content per nuclei.


Subject(s)
Cardiomegaly/metabolism , DNA/biosynthesis , Myocardium/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Tamoxifen/analogs & derivatives , Animals , Cardiomegaly/pathology , Cell Cycle/drug effects , Cell Division/drug effects , Disease Models, Animal , Gene Expression Regulation/drug effects , Heart/drug effects , Humans , Ligands , Mice , Mice, Inbred C3H , Mice, Transgenic , Myocardium/pathology , Myosin Heavy Chains/genetics , Organ Size/drug effects , Organ Specificity/drug effects , Ploidies , Proto-Oncogene Proteins c-myc/genetics , Receptors, Estrogen/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Tamoxifen/pharmacology , Up-Regulation/drug effects , Ventricular Myosins/genetics
20.
Am J Respir Crit Care Med ; 164(12): 2239-42, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11751193

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic and often fatal disorder. Fibroplasia and deposition of extracellular matrix are dependent, in part, on angiogenesis and vascular remodeling. We obtained open lung biopsies from patients undergoing thoracic surgery for reasons other than interstitial lung disease (control) (n = 78) and from patients with IPF (n = 91). We found that levels of epithelial neutrophil-activating peptide 78 (ENA-78) were greater from tissue specimens of IPF patients, as compared with control subjects. When ENA-78 was depleted from IPF tissue specimens, tissue-derived angiogenic activity was markedly reduced. Immunolocalization of ENA-78 demonstrated that hyperplastic Type II pneumocytes and macrophages were the predominant cellular sources of ENA-78. These findings support the notion that ENA-78 may be an important additional factor that regulates angiogenic activity in IPF.


Subject(s)
Angiogenesis Inducing Agents/physiology , Chemokines, CXC , Interleukin-8/analogs & derivatives , Interleukin-8/physiology , Lung/blood supply , Neovascularization, Pathologic , Pulmonary Fibrosis/physiopathology , Angiogenesis Inducing Agents/metabolism , Animals , Chemokine CXCL5 , Cornea/blood supply , Enzyme-Linked Immunosorbent Assay , Epithelium/metabolism , Epithelium/pathology , Fibroblasts/pathology , Humans , Interleukin-8/metabolism , Lung/metabolism , Lung/pathology , Macrophages/metabolism , Macrophages/pathology , Neovascularization, Pathologic/physiopathology , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology , Rats , Rats, Long-Evans
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