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1.
Top Stroke Rehabil ; 31(2): 157-166, 2024 03.
Article in English | MEDLINE | ID: mdl-37415422

ABSTRACT

INTRODUCTION: There is limited evidence on the costs and outcomes of patients with aphasia after stroke. The aim of this study was to estimate costs in patients with aphasia after stroke according to the aphasia therapies provided. METHODS: A three-arm, prospective, randomized, parallel group, open-label, blinded endpoint assessment trial conducted in Australia and New Zealand. Usual ward-based care (Usual Care) was compared to additional usual ward-based therapy (Usual Care Plus) and a prescribed and structured aphasia therapy program in addition to Usual Care (the VERSE intervention). Information about healthcare utilization and productivity were collected to estimate costs in Australian dollars for 2017-18. Multivariable regression models with bootstrapping were used to estimate differences in costs and outcomes (clinically meaningful change in aphasia severity measured by the WAB-R-AQ). RESULTS: Overall, 202/246 (82%) participants completed follow-up at 26 weeks. Median costs per person were $23,322 (Q1 5,367, Q3 52,669, n = 63) for Usual Care, $26,923 (Q1 7,303, Q3 76,174, n = 70) for Usual Care Plus and $31,143 (Q1 7,001. Q3 62,390, n = 69) for VERSE. No differences in costs and outcomes were detected between groups. Usual Care Plus was inferior (i.e. more costly and less effective) in 64% of iterations, and in 18% was less costly and less effective compared to Usual Care. VERSE was inferior in 65% of samples and less costly and less effective in 12% compared to Usual Care. CONCLUSION: There was limited evidence that additional intensively delivered aphasia therapy within the context of usual acute care provided was worthwhile in terms of costs for the outcomes gained.


Subject(s)
Aphasia , Stroke Rehabilitation , Stroke , Humans , Stroke/complications , Stroke/therapy , Cost-Benefit Analysis , Prospective Studies , Speech , Australia , Aphasia/etiology , Aphasia/rehabilitation
2.
Top Stroke Rehabil ; 30(6): 603-609, 2023 09.
Article in English | MEDLINE | ID: mdl-35786371

ABSTRACT

BACKGROUND: People with communication disabilities post-stroke have poor quality-of-life. OBJECTIVES: We aimed to explore the association of self-reported communication disabilities with different dimensions of quality-of-life between 90 and 180 days post-stroke. METHODS: Cross-sectional survey data were obtained between 90 and 180 days post-stroke from registrants in the Australian Stroke Clinical Registry recruited from three hospitals in Queensland. The usual follow-up survey included the EQ5D-3L. Responses to the Hospital Anxiety and Depression Scale, and extra questions (e.g. communication disabilities) were also collected. We used χ2 statistics to determine differences. RESULTS: Overall, 244/647 survivors completed the survey. Respondents with communication disabilities (n = 72) more often reported moderate to extreme problems in all EQ5D-3L dimensions, than those without communication disabilities (n = 172): anxiety or depression (74% vs 40%, p < .001), pain or discomfort (58% vs 39%, p = .006), self-care (46% vs 18%, p < .001), usual activities (77% vs 49%, p < .001), and mobility (68% vs 35%, p < .001). Respondents with communication disabilities reported less fatigue (66% vs 89%, p < .001), poorer cognitive skills (thinking) (16% vs 1%, p < .001) and lower social participation (31% vs 6%, p < .001) than those without communication disabilities. CONCLUSIONS: Survivors of stroke with communication disabilities are more negatively impacted across different dimensions of quality-of-life (as reported between 90 and 180 days post-stroke) compared to those without communication disabilities. This highlights the need for timely and on-going comprehensive multidisciplinary person-centered support.


Subject(s)
Stroke , Humans , Stroke/complications , Stroke/psychology , Cross-Sectional Studies , Australia , Quality of Life/psychology , Survivors/psychology
3.
Indian J Cancer ; 53(2): 322-324, 2016.
Article in English | MEDLINE | ID: mdl-28071638

ABSTRACT

INTRODUCTION: Nearly 15% of youth in India use tobacco. However, few studies have explored the use, knowledge, and attitudes of smokeless tobacco use among youth. AIM: To determine the patterns of use as well as knowledge and perceptions of smokeless tobacco among youth in Mumbai attending municipal schools. MATERIALS AND METHODS: A cross-sectional survey was performed among 1053 students in the 8th and 9th grades in 16 municipal schools in Mumbai to determine the knowledge and perceptions about smokeless tobacco products as well as the patterns of use. RESULTS AND CONCLUSIONS: Ever use of smokeless tobacco was reported by 47 (4.7%) students in the survey. Twenty-nine (2.9%) students reported ever using smoked tobacco. Students were more likely to identify cigarettes and bidis as tobacco products compared to smokeless tobacco products such as gutkha, mishri, and khaini. Betel nut products were used by 178 (17.9%) students. The high rate of smokeless tobacco and betel nut use coupled with low levels of knowledge about their contents and harms suggests that tobacco control programs targeting youth should ensure that these products are adequately explained and understood by students.


Subject(s)
Areca/adverse effects , Tobacco, Smokeless/adverse effects , Cross-Sectional Studies , Female , Humans , India , Male , Schools , Students
4.
Allergy ; 68(9): 1143-9, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23991716

ABSTRACT

BACKGROUND: Recent studies have suggested that the birth order effect in allergy may be established during the prenatal period and that the protective effect may originate in the mother. HLA class II disparity between mother and foetus has been associated with significantly increased Th1 production. In this study, we investigated whether production of HLA antibodies 4 years after pregnancy with index child is associated with allergic outcomes in offspring at 8 years. METHODS: Anti-HLA class I and II antibodies were measured in maternal serum (n = 284) and levels correlated to numbers of pregnancies and birth order, and allergic outcomes in offspring at 8 years of age. RESULTS: Maternal anti-HLA class I and II antibodies were significantly higher when birth order, and the number of pregnancies were larger. Anti-HLA class II, but not class I antibodies were associated with significantly less atopy and seasonal rhinitis in the offspring at age 8 years. Mothers with nonatopic (but not atopic) offspring had a significant increase in anti-HLA class I and II antibodies with birth order. CONCLUSION: This study suggests that the 'birth order' effect in children may be due to parity-related changes in the maternal immune response to foetal antigens. We have observed for the first time an association between maternal anti-HLA class II antibodies and protection from allergy in the offspring. Further work is required to determine immunologically how HLA disparity between mother and father can protect against allergy.


Subject(s)
Antibodies/immunology , Histocompatibility Antigens Class II/immunology , Hypersensitivity/immunology , Prenatal Exposure Delayed Effects/immunology , Adult , Antibodies/blood , Child , Female , Histocompatibility Antigens Class I/immunology , Humans , Hypersensitivity/prevention & control , Male , Pregnancy , Risk Factors
5.
Intern Med J ; 42(8): 874-9, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22212153

ABSTRACT

BACKGROUND/AIMS: Pulmonary arterial hypertension (PAH) frequently accompanies childhood congenital heart disease (CHD) and may persist into adult life. The advent of specific PAH therapies for PAH prompted formation of a national Australian and New Zealand registry in 2010 to document the incidence, demographics, presentation and outcomes for these patients. METHODS: This multicentre, prospective, web-based registry enrols patients with CHD-associated PAH being followed in a tertiary centre. The inclusion criteria stipulated patient age ≥16 years, a measured mean pulmonary arterial pressure >25 mmHg at rest or echocardiographical evidence of PAH or a diagnosis of Eisenmenger syndrome, and followed since 1 January 2000. A single observer collected standardised data during a series of site visits. RESULTS: Of the first 50 patients enrolled, 30 (60%) were female. The mean age (standard deviation (SD)) at the time of PAH diagnosis or confirmation in an adult centre was 27.23 (10.07) years, and 32 (64%) patients are currently aged >30 years. Fourteen (28%) patients were in World Health Organization Functional Class II and 36 (72%) in Class III at the time of diagnosis. Forty-seven of 50 (94%) had congenital systemic-pulmonary shunts, and 36 (72%) never underwent intervention. Thirteen (26%) had Down syndrome. Confirmation of PAH by recent cardiac catheterisation was available in 30 (60%) subjects. During follow up, a total of 32 (64%) patients received a PAH-specific therapy. CONCLUSIONS: CHD associated with PAH in adult life has resulted in a new population with unique needs. This registry will allow documentation of clinical course and long-term outcomes for these patients.


Subject(s)
Heart Defects, Congenital/epidemiology , Hypertension, Pulmonary/epidemiology , Registries , Adult , Female , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/therapy , Humans , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/therapy , Male , Prospective Studies , Young Adult
6.
Biomed Chromatogr ; 26(5): 566-70, 2012 May.
Article in English | MEDLINE | ID: mdl-21905056

ABSTRACT

Milrinone is a bipyridine phosphodiesterase inhibitor with positive inotropic and vasodilatory effects. As interest in longer term use of intravenous therapy increases, it becomes essential to monitor its plasma concentration owing to a narrow therapeutic range, an increased half-life in renal failure and toxicity associated with high levels. A high-performance liquid chromatography (HPLC) method with mass (MS) detection using a triple quadrupole mass spectrometer is presented. The method was compared with the UV/HPLC method and validated according to current international guidelines. Coefficients of variation of less than 7.5% were obtained across the therapeutic range and 18.3% at 2.4 ng/mL, the lower limit of quantitation. Plasma from 13 cardiac surgery patients receiving standard intravenous doses of milrinone were measured. Eight patients achieved therapeutic milrinone levels within 3-4 h post start of infusion, one was borderline sub-therapeutic and four patients achieved levels that were above the upper limit of the therapeutic range and potentially toxic. This method offers high sensitivity, is rapid, easy to use and requires minimal amount of sample. We believe this method could become the reference procedure for clinical monitoring of milrinone and help to improve the safety of the use of this drug in patients with cardiac failure.


Subject(s)
Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods , Milrinone/blood , Drug Monitoring/methods , Drug Stability , Heart Failure/blood , Heart Failure/surgery , Humans , Linear Models , Milrinone/administration & dosage , Milrinone/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity
7.
Am J Transplant ; 11(2): 312-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21219570

ABSTRACT

Preformed donor HLA-specific antibodies are a known indicator for poor patient survival after cardiac transplantation. The role of de novo donor-specific antibodies (DSA) formed after cardiac transplantation is less clear. Here we have retrospectively analyzed 243 cardiac transplant recipients, measuring HLA antibody production every year after transplantation up to 13 years post-transplant. Production of de novo DSA was analyzed in patients who had been negative for DSA prior to their transplant. DSA including transient antibodies were associated with poor patient survival (p = 0.0018, HR = 3.198). However, de novo and persistent DSA was strongly associated with poor patient survival (p = 0.0001 HR = 4.351). Although complement fixing persistent DSA correlated with poor patient survival, this was not increased compared to noncomplement fixing persistent DSA. Multivariable analysis indicated de novo persistent DSA to be an independent predictor of poor patient survival along with HLA-DR mismatch and donor age. Only increasing donor age was found to be an independent risk factor for earlier development of CAV. In conclusion, patients who are transplanted in the absence of pre-existing DSA make de novo DSA after transplantation which are associated with poor survival. Early and regular monitoring of post-transplant DSA is required to identify patients at risk of allograft failure.


Subject(s)
HLA Antigens/immunology , Heart Transplantation/adverse effects , Heart Transplantation/immunology , Isoantibodies/biosynthesis , Adult , Antibody Specificity , Complement Fixation Tests , Female , Graft Rejection/etiology , Graft Rejection/immunology , HLA-DR Antigens/immunology , Heart Transplantation/mortality , Histocompatibility Testing , Humans , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Retrospective Studies , Risk Factors , Tissue Donors
8.
Am J Transplant ; 9(8): 1912-9, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19563343

ABSTRACT

Little is known about the effect of MICA antibodies (Abs) on cardiac allograft function and survival. Pretransplant and posttransplant serum from 491 and 196 adult cardiac allograft recipients, respectively, has been investigated for MICA Abs, donor specificity and the effect of MICA Abs on graft survival, acute rejection episodes (AR) and cardiac allograft vasculopathy (CAV). Patients with HLA Abs (11.6%) were excluded from the analysis. A total of 11.8% of patients had MICA Abs, without HLA Abs, before their transplant. Actuarial graft survival demonstrated slightly better survival of patients with donor-specific MICA Abs at 1 and 5 years (88.9% and 83.3%) than patients negative for MICA Abs (72% and 63.7%, p = 0.051). After transplantation, 15.8% of patients produced MICA Abs, and in 17 patients these were produced de novo. There was no effect of pretransplant or posttransplant production of MICA Abs on numbers of AR episodes in year 1, or CAV assessed at years 3 and 5. Immunocytochemistry of cardiac biopsies from 11 patients did not demonstrate a presence of MICA. Sera from only 4/69 patients with MICA Abs fixed complement prior to transplantation and from 7/38 patients following transplantation. In conclusion, this study suggests that MICA Abs do not adversely affect the outcome of cardiac transplantation.


Subject(s)
Antibodies/immunology , Graft Survival/immunology , Heart Transplantation/immunology , Histocompatibility Antigens Class I/immunology , Adult , Antibodies/blood , Biopsy , Cohort Studies , Endothelium, Vascular/immunology , Endothelium, Vascular/pathology , Female , Humans , Male , Middle Aged , Myocardium/immunology , Myocardium/pathology , Retrospective Studies , Transplantation, Homologous , Treatment Outcome
10.
J Leukoc Biol ; 83(2): 263-71, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17974709

ABSTRACT

Anti-vimentin antibodies (AVA) are associated with autoimmunity and solid organ transplantation, conditions associated with vascular disease, but their contribution to disease pathogenesis is unknown. Here, we have examined interactions between AVA (mAb and serum from patients) and various leukocyte populations using whole blood and flow cytometry. Normal blood treated with patient sera containing high AVA-IgM titers or with a vimentin-specific monoclonal IgM led to activation of platelets and other leukocytes, as demonstrated by induced expression of P-selectin, fibrinogen, tissue factor, and formation of platelet:leukocyte (P:L) conjugates and a reduction in platelet counts. This activity was antigen (vimentin)-specific and was not mediated by irrelevant IgM antibodies. Flow cytometry demonstrated that AVA do not bind directly to resting platelets in whole blood, but they bind to approximately 10% of leukocytes. Supernatant, derived from AVA-treated leukocytes, induced platelet activation, as measured by the generation of platelet microparticles, when added to platelet-rich plasma. When AVA were added to whole blood in the presence of CV-6209, a platelet-activating factor (PAF) receptor inhibitor, platelet depletion was inhibited. This suggests that PAF is one of the mediators released from AVA-activated leukocytes that leads to P:L conjugation formation and platelet activation. In summary, AVA bind to leukocytes, resulting in release of a PAF and prothrombotic factor that exert a paracrine-activating effect on platelets. Overall, this proposed mechanism may explain the pathogenesis of thrombotic events in autoimmune diseases associated with AVA.


Subject(s)
Autoantibodies/immunology , Autoimmune Diseases/blood , Blood Platelets/immunology , Immunoglobulin M/immunology , Leukocytes/immunology , Platelet Activating Factor/physiology , Platelet Activation/immunology , Thrombophilia/etiology , Vimentin/immunology , Apoptosis/immunology , Autoantibodies/blood , Autoimmune Diseases/complications , Autoimmune Diseases/immunology , Cell Adhesion/immunology , Complement C3d/metabolism , Culture Media, Conditioned/pharmacology , Fibrinogen/metabolism , Humans , Immunoglobulin M/blood , Immunosorbent Techniques , Leukocytes/drug effects , Leukocytes/metabolism , P-Selectin/metabolism , Platelet Activating Factor/metabolism , Pyridinium Compounds/pharmacology , Recombinant Proteins/immunology , Thromboplastin/metabolism , Vimentin/genetics
11.
Am J Transplant ; 7(12): 2809-15, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17908268

ABSTRACT

The standard method to detect pretransplant antibodies has been the complement dependent cytotoxicity (CDC) test of donor leukocytes. Solid phase assays to detect HLA antibodies in pretransplant serum reveal a greater number of sensitized patients, but their clinical impact is less certain. Here we have developed a method of detecting C4d fixing HLA antibodies on Luminex beads. Pretransplant serum from 565 cardiac transplant patients was retrospectively tested for the presence of HLA antibodies using CDC, HLA coated Luminex beads and C4d deposition on Luminex beads, and the results correlated with graft survival. Whereas 5/565 patients had CDC positive donor specific antibodies (DSA) before their transplant, this number was increased by 19 using Luminex beads. The 1-year survival of CDC -ve/Luminex +ve patients with DSA (n = 19) was 42% compared with 77% for CDC -ve/Luminex +ve without DSA (n = 39, p = 0.0039). Fixation of C4d (22/67 Luminex positive sera) had a negative effect on graft outcome; 1-year graft survival was, C4d +ve/DSA +ve (n = 11) 20%, C4d +ve/DSA -ve (n = 11) 91%, C4d -ve DSA +ve (n = 13) 54%, C4d -ve DSA -ve (n = 32) 75%, compared with 75% for antibody-negative patients (p = 0.0002). In conclusion, detection of Luminex +ve DSA in pretransplant serum provides a powerful negative predictor of graft survival, especially if they bind C4d.


Subject(s)
Antibodies/blood , Complement C4b/immunology , Graft Rejection/immunology , HLA Antigens/immunology , Heart Transplantation/immunology , Microspheres , Peptide Fragments/immunology , Adolescent , Adult , Aged , Antibodies/analysis , Complement C4b/analysis , Cytotoxicity Tests, Immunologic , Female , Graft Rejection/diagnosis , Graft Survival/immunology , Humans , Male , Middle Aged , Multivariate Analysis , Peptide Fragments/analysis , Predictive Value of Tests , Prognosis , Retrospective Studies
12.
Am J Transplant ; 6(7): 1712-7, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16827875

ABSTRACT

Implantation of left ventricular assist devices (LVAD) is associated with HLA antibody sensitization. The objective of this study was to determine the specificity of antibodies produced by LVAD recipients using a combination of ELISA, Luminex and microcytotoxicity assays. Fifty-one LVAD patients were studied, from 44 to 838 days post-implantation. No patient developed HLA antibodies, although 24 produced IgG antibodies detectable in both ELISA and Luminex assays. These antibodies manifest as positive reactions with class I and class II wells of the ELISA and also blank wells. In Luminex assays, they produce high MFI readings with the negative control beads. Antibodies were detected 18 to 228 days after implantation. This reactivity was found to be directed against bovine serum albumin (BSA), commonly used to block non-specific binding in ELISA and Luminex assays; absorption of sera with BSA-coated beads completely abrogated reactivity in all solid phase assays, but did not eliminate anti-HLA antibodies in control sera. Ten of the 24 patients have proceeded to transplantation, with a 1-year graft survival of 69%. In conclusion, it appears that implantation of LVADS disrupts immunoregulatory pathways leading to production of anti-albumin antibodies. These can be misinterpreted as anti-HLA antibodies in solid phase assays.


Subject(s)
Antibodies/immunology , Cardiac Surgical Procedures , HLA Antigens/immunology , Heart Ventricles/surgery , Adult , Albumins/immunology , Animals , Cattle , Enzyme-Linked Immunosorbent Assay , Humans , Survival Rate
13.
Article in English | MEDLINE | ID: mdl-16021917

ABSTRACT

Human endothelial activity of ecto-5'-nucleotidase (E5'N) is several times higher than in pig endothelial cells. This may have implication for xenotransplantation due to the role this enzyme plays in conversion of pro-inflammatory and pro-aggreggatory nucleotides into anti-inflammatory and antiaggregatory adenosine. We have shown in this study that human E5'N can be functionally expressed in pig endothelial cells leading to increased adenosine production from both extracellular AMP and ATP. We suggest that E5'N expression in transgenic pigs for xenotransplantation may help to prolong graft survival.


Subject(s)
5'-Nucleotidase/biosynthesis , 5'-Nucleotidase/chemistry , Adenosine/metabolism , Endothelium, Vascular/cytology , Adenosine Triphosphate/chemistry , Adenosine Triphosphate/metabolism , Animals , Animals, Genetically Modified , Cell Line , Cells, Cultured , DNA, Complementary/metabolism , Endothelium, Vascular/metabolism , Graft Survival , Humans , Inflammation/pathology , Swine , Time Factors , Transplantation, Heterologous
14.
Circ Res ; 97(2): 192-8, 2005 Jul 22.
Article in English | MEDLINE | ID: mdl-15976317

ABSTRACT

Experimental studies have suggested that protective genes protect allografts from cardiac allograft vasculopathy (CAV), the major complication after cardiac transplantation. Here we have sought to confirm this hypothesis using long-term heart transplant recipients. Twenty-two patients that were 9 years or older after transplant were investigated; 11 of these were without angiographic evidence of CAV; 11 had developed early CAV at 1 to 3 years after transplant. To identify proteins that may act as protectors from CAV, a global proteomic approach was used comparing cardiac biopsies from 12 patients taken within the first 2 weeks after transplant and those taken after 9 years from the same patient. Proteins were separated by 2-D gel-electrophoresis, detected by silver staining, and analyzed using Progenesis software. A particular protein spot was found in 4/6 biopsies from patients without CAV, but absent from 5/6 biopsies from those with CAV (P=0.24); however, quantitative analysis of spot intensity showed a significant difference (0.061+/-0.05 versus 0.003+/-0.01, P=0.04). This spot was identified by mass spectrometry and a combination of techniques as a diphosphorylated form of HSP27. Immunohistochemistry of further biopsies not only validated that HSP27 was more abundantly expressed on biopsies without CAV but also showed it to be localized to blood vessels. In contrast, vessels from patients with CAV did not express HSP27 (P=0.028x10(-4)). Immunohistochemistry of 12 further early biopsies and nontransplanted heart showed HSP27 to be present in normal blood vessels. These findings suggest that expression of a specific diphosphorylated form of HSP27 is associated with healthy blood vessels; it appears to be lost from vessels of patients with graft vasculopathy.


Subject(s)
Coronary Artery Disease/prevention & control , Graft Rejection/prevention & control , Heart Transplantation/adverse effects , Heat-Shock Proteins/physiology , Apoptosis , Biopsy , Coronary Angiography , Coronary Artery Disease/etiology , Coronary Vessels/pathology , Graft Rejection/etiology , Heat-Shock Proteins/analysis , Humans , Immunohistochemistry , Phosphorylation
16.
Clin Exp Immunol ; 126(1): 173-9, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11678915

ABSTRACT

A HUVEC cDNA library was screened with sera from two patients who had developed transplant-associated coronary artery disease (TxCAD) following cardiac transplantation. A total of six positive clones were isolated from a primary screen of 40 000 genes. Subsequent DNA sequence analysis identified these to be lysyl tRNA synthetase, ribosomal protein L7, ribosomal protein L9, beta transducin and TANK. Another gene whose product could not be identified showed homology to a human cDNA clone (DKFZp566M063) derived from fetal kidney. Full-length constructs of selected genes were expressed as his-tag recombinant fusion proteins and used to screen a wider patient base by ELISA to determine prevalence and association with TxCAD. Of these ribosomal protein L7 showed the highest prevalence (55.6%) with TxCAD sera compared to 10% non-CAD.


Subject(s)
Autoantigens/immunology , Autoimmune Diseases/immunology , Coronary Artery Disease/immunology , Endothelium, Vascular/immunology , Heart Transplantation/adverse effects , Ribosomal Proteins/immunology , Adult , Autoantibodies/blood , Autoimmune Diseases/etiology , Coronary Artery Disease/etiology , Enzyme-Linked Immunosorbent Assay , Gene Library , Humans , Kinetics , Male , Middle Aged , Umbilical Veins/cytology
17.
J Thorac Cardiovasc Surg ; 122(1): 129-35, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11436045

ABSTRACT

OBJECTIVES: Valve allografts produce an immune response, which can influence their performance. The exact role of the interaction between recipient T cells and the different cellular components of the donor valve in stimulating an immune response is not known. Therefore the T-cell response to valve endothelial and interstitial cells was investigated in vitro. METHODS: Valve endothelial and interstitial cells were characterized for cell-surface molecules before and after interferon gamma treatment by means of a panel of specific monoclonal antibodies and flow cytometry. The proliferative response of highly purified T lymphocytes was used to assess the immunogenicity of cultured valve endothelial and interstitial cells. This was further investigated by using a 2-step tolerance-induction protocol. RESULTS: Valve endothelial and interstitial cells express similar levels of human leukocyte antigens and adhesion and costimulatory molecules, which are either induced or upregulated after interferon gamma treatment. T-cell responses to endothelial cells were detected after interferon gamma treatment, but responses to interferon gamma-treated interstitial cells were not detected. This lack of response resulted in the induction of T-cell anergy, which was reversed by the presence of the costimulatory molecule B7-1. CONCLUSIONS: Although valve endothelial and interstitial cells express a similar range of cell-surface molecules, it is only the endothelial cells that are immunogenic. In addition, we have shown that these 2 cell types interact in a donor-specific manner to orchestrate the immune response and therefore may have clinical relevance in the allogeneic response of the heart valve recipients.


Subject(s)
Clonal Anergy/immunology , Endothelium/immunology , Heart Valves/immunology , T-Lymphocytes/immunology , Antibodies, Monoclonal , Cell Division/immunology , Cells, Cultured , Flow Cytometry , Graft Rejection/immunology , Heart Valves/cytology , Humans , Interferon-gamma/pharmacology , Lymphocyte Activation/immunology , Transplantation, Homologous/immunology , Up-Regulation
18.
J Immunol ; 167(1): 532-41, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11418692

ABSTRACT

Blockade of the CD40-CD154 pathway can inhibit CD4(+) T cell activation but is unable to prevent immune responses mediated by CD8(+) T cells. However, even in the absence of CD8(+) T cells, inhibition of the CD40-CD154 pathway is insufficient to prevent the development of transplant arteriosclerosis. This study investigated the mechanisms of transplant arteriosclerosis in the absence of the CD40 pathway. C57BL/6 CD40(-/-) (H2(b)) recipients were transplanted with MHC-mismatched BALB/c (H2(d)) aortas. Transplant arteriosclerosis was evident in both CD40(-/-) and CD40(+/-) mice (intimal proliferation was 59 +/- 5% for CD40(-/-) mice vs 58 +/- 4% for CD40(+/-) mice) in the presence or absence of CD8(+) T cells (intimal proliferation was 46 +/- 7% for CD40(-/-) anti-CD8-treated mice vs 50 +/- 10% for CD40(+/-) anti-CD8-treated mice), confirming that CD8(+) T cells are not essential effector cells for the development of this disease. In CD40(-/-) recipients depleted of CD8(+) T cells, the number of eosinophils infiltrating the graft was markedly increased (109 +/- 24 eosinophils/grid for CD40(-/-) anti-CD8-treated mice vs 28 +/- 7 for CD40(+/-) anti-CD8-treated mice). The increased presence of eosinophils correlated with augmented intragraft production of IL-4. To test the hypothesis that IL-4 was responsible for the intimal proliferation, CD8 T cell-depleted CD40(-/-) recipients were treated with anti-IL-4 mAb. This resulted in significantly reduced eosinophil infiltration into the graft (12 +/- 5 eosinophils/grid for CD40(-/-) anti-CD8(+), anti-IL-4-treated mice vs 109 +/- 24 for CD40(-/-) anti-CD8-treated mice), intragraft eotaxin, CCR3 mRNA production, and the level of intimal proliferation (18 +/- 5% for CD40(-/-) anti-CD8(+)-, anti-IL-4-treated mice vs 46 +/- 7% for CD40(-/-) anti-CD8-treated mice). In conclusion, elevated intragraft IL-4 production results in an eosinophil infiltrate and is an important mechanism for CD8(+) T cell-independent transplant arteriosclerosis in the absence of CD40-CD154 costimulation.


Subject(s)
Aorta, Thoracic/transplantation , Arteriosclerosis/immunology , CD40 Antigens/genetics , CD40 Ligand/genetics , Chemokines, CC , Interleukin-4/physiology , Animals , Antibodies, Monoclonal/administration & dosage , Antigen-Presenting Cells/immunology , Antigen-Presenting Cells/metabolism , Arteriosclerosis/genetics , Arteriosclerosis/pathology , Arteriosclerosis/prevention & control , CD4-Positive T-Lymphocytes/pathology , CD40 Antigens/biosynthesis , CD40 Antigens/physiology , CD40 Ligand/physiology , CD8-Positive T-Lymphocytes/pathology , Cell Movement/genetics , Cell Movement/immunology , Chemokine CCL11 , Cytokines/biosynthesis , Cytokines/genetics , Eosinophils/pathology , H-2 Antigens/immunology , Histocompatibility Antigen H-2D , Interferon-gamma/antagonists & inhibitors , Interferon-gamma/genetics , Interleukin-4/antagonists & inhibitors , Interleukin-4/genetics , Interleukin-4/immunology , Isoantibodies/biosynthesis , Lymphocyte Depletion , Macrophage-1 Antigen/biosynthesis , Macrophages/immunology , Macrophages/pathology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/antagonists & inhibitors , RNA, Messenger/biosynthesis , Receptors, CCR3 , Receptors, Chemokine/biosynthesis , Receptors, Chemokine/genetics
19.
Cardiovasc Res ; 50(3): 547-55, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11376630

ABSTRACT

OBJECTIVE: Intercellular adhesion molecule (ICAM)-1 is an immunoglobulin-like cell adhesion molecule expressed by several cell types, including proliferating vascular smooth muscle cells (VSMC). Cross-linking ICAM-1 on the surface of different cell types has previously been shown to cause an increase in cellular activation within the cytoplasm. Here, our objective was to examine events following ligation of ICAM-1 on the surface of human VSMC. METHODS: VSMC were isolated by explant from human pulmonary arteries or aortic tissue from cardiac transplant donors. ICAM-1 was ligated with monoclonal antibodies, followed by cross-linking with a secondary antibody. Activation of signalling pathways, proliferation and expression of a second adhesion molecule, vascular cell adhesion molecule (VCAM)-1 were investigated. RESULTS: ICAM-1 cross-linking caused an increase in activation of extracellular regulated kinase (Erk)-1/-2 and Jun N-terminal kinase (JNK)-1/-2. mRNA and protein for VCAM-1 was observed after ICAM-1 cross-linking, and this was abrogated by addition of an upstream inhibitor of Erk-1/-2, PD98059. No increase in cell proliferation was observed. CONCLUSIONS: Ligation of ICAM-1 on the surface of vascular smooth muscle cells in vitro, leads to the expression of adhesion molecules associated with monocyte infiltration, but does not contribute to smooth muscle cell proliferation. In vivo, this might lead to prolongation of the inflammatory response within diseased blood vessels, by arresting monocytes within atherosclerotic plaques.


Subject(s)
Intercellular Adhesion Molecule-1/metabolism , Muscle Proteins/metabolism , Muscle, Smooth, Vascular/metabolism , Vascular Cell Adhesion Molecule-1/metabolism , Cell Communication/physiology , Cell Culture Techniques , Cell Division/physiology , Gene Expression Regulation , Humans , Muscle, Smooth, Vascular/cytology , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/physiology , Vascular Cell Adhesion Molecule-1/genetics
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