A challenging case of eosinophilic myocarditis leading to heart failure and transplantation.

The large spectrum of etiologies, severities, and histologic appearances of eosinophilic myocarditis (EoM) poses challenges to its diagnosis and management. Endomyocardial biopsy is the current gold standard for diagnosis. However, cardiovascular magnetic resonance imaging is becoming more frequently used to diagnose acute myocarditis because of enhanced sensitivity when compared to histopathologic examination, and its less invasive nature. We report a complicated case of EoM in a male in his mid-thirties that led to fulminant cardiogenic shock that required immunosuppressive therapy on day 5 of admission and implantation of a left ventricular assist device (LVAD) on day 30. EoM was diagnosed on histopathologic examination of the resected fragment of the left ventricular myocardium. Nine months after the initial presentation, the patient ultimately required heart transplantation. The explanted heart showed minimal residual interstitial inflammation with evidence of mildly active intimal arteritis and patchy areas of interstitial fibrosis. In this report, we describe our patient's clinical features and correlate them with imaging and histopathologic findings to illustrate the difficulty in diagnosing EoM, particularly in this complicated patient that ultimately required heart transplantation. The diagnosis can be challenging due to the variable histopathologic features, clinical presentation, and utilization of therapeutic medications and devices.

Early, rapidly progressive vasculopathy in a transplanted heart: A possible complication of COVID-19.

The epidemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has had a significant global impact, especially on immunosuppressed populations such as heart transplant recipients. While SARS-CoV-2 initially infects the respiratory system, cardiovascular complications induced by coronavirus disease 2019 (COVID-19) include cardiac arrest, myocardial infarction, heart failure, myocarditis, arrhythmia, acute myocyte injury, thrombotic events, and cardiogenic shock. Here, we present a case of a 45-year-old African American male who tested positive for COVID-19 infection six months after receiving a heart transplant. The patient was asymptomatic initially, but two weeks later he developed dyspnea, early satiety, and abdominal bloating. The patient was admitted to the hospital for acute renal failure and subsequently diagnosed with moderate acute T cell-mediated allograft rejection (Grade 2R) by endomyocardial biopsy. Three months after testing positive for COVID-19, the patient suffered a sudden cardiac death. At autopsy, the epicardium was diffusely edematous and showed vascular congestion. The coronary arteries showed a striking concentric narrowing of lumens and diffusely thickened arterial walls of all major extramural arteries deemed consistent with a rapidly progressive form of cardiac allograft vasculopathy (CAV). SARS-CoV-2 nucleocapsid protein was localized by immunohistochemistry (IHC) in endothelial cells of venules and capillaries within the epicardium. Our localization of SARS-CoV-2 in coronary vessel endothelial cells by IHC suggests that endothelial cell infection, endotheliitis, and immune-related inflammation may be a primary mechanism of vascular injury. The present case represents an early onset rapidly progressive form of CAV. This case may be the first case of post-transplant arteriopathy occurring in such a short time that includes corresponding autopsy, surgical pathology, and IHC data.

Endomyocardial biopsy facilitates diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA): a case report.

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare small vessel leukocytoclastic vasculitis that affects multiple organs and is often associated with anti-neutrophil cytoplasmic antibody (ANCA). EGPA presenting with cardiac involvement is often ANCA-negative, difficult to diagnose, and often fatal. The treatment and prognosis and can be quite different for other conditions included in the differential diagnosis. Imaging modalities have proven unreliable, and the skin is the most commonly biopsied site for histological diagnosis. CASE SUMMARY: We report a case of a 55-year-old Hispanic man who presented with a non-ST-elevated myocardial infarction, reduced ejection fraction heart failure, and hypereosinophilia. The patient's clinical history also included poorly controlled asthma and sinonasal polyps. Despite ANCA titers within the normal range and a skin biopsy lacking evidence of EPGA, high clinical suspicion prompted an endomyocardial biopsy on day nine from hospital admission which facilitated the diagnosis of ANCA-negative EGPA-induced cardiomyopathy. Six months of follow-up revealed that therapeutic response, as measured by the cardiac ejection fraction, directly correlated with medication compliance. CONCLUSION: Endomyocardial biopsy aids in the diagnosis of EGPA and initiates use of appropriate therapy.

Redox regulation of hepatic NLRP3 inflammasome activation and immune dysregulation in trichloroethene-mediated autoimmunity.

Trichloroethene (TCE) exposure is associated with the development of various autoimmune diseases (ADs), including autoimmune hepatitis (AIH) and systemic lupus erythematosus (SLE), potentially through the generation of excessive reactive oxygen and nitrogen species (RONS; oxidative stress). However, the mechanisms by which oxidative stress contributes to these TCE-mediated ADs are not fully understood, and are the focus of current investigation. Female MRL+/+ mice were treated with TCE along with or without antioxidant N-acetylcysteine (NAC) for 6 weeks (TCE, 10 mmol/kg, i. p., every 4th day; NAC, 250 mg/kg/day via drinking water). TCE-treated mice had elevated antinuclear antibodies (ANA) and 4-hydroxynonenal (HNE)-specific circulating immune complexes, suggesting the association of TCE-induced oxidative stress with autoimmune response. In addition, TCE exposure led to prominent lobular inflammation with sinusoid dilation, increased sinusoidal cellularity and increased staining for proliferating cell nuclear antigen (PCNA), confirming inflammatory and hepatocellular cell proliferation. Importantly, TCE exposure resulted in the activation of hepatic inflammasome (NLRP3 and caspase-1) and up-regulation of pro-inflammatory cytokine IL-1ß, and these changes were attenuated by NAC supplementation. TCE treatment also led to dysregulation of hepatic immune response as evident from markedly increased hepatic lymphocyte infiltration (especially B cells) and imbalance between Tregs (decreased) and Th17 cells (increased). Interestingly, TCE-mediated dysregulation of various hepatic and splenic immune cells was also effectively attenuated by NAC. Taken together, our findings provide evidence for TCE-mediated inflammasome activation, infiltration of various immune cells, and skewed balance of Treg and Th17 cells in the liver. The attenuation of TCE-mediated hepatic inflammasome activation and immune responses by NAC further supports a critical role of oxidative stress in TCE-mediated inflammation and autoimmunity. These novel findings could help in designing therapeutic strategies for such ADs.

A Case of Previously Unsuspected Cardiac Sarcoidosis Diagnosed at Autopsy and 23-Year Review of One Institution's Sarcoidosis Deaths.

Sarcoidosis is a noncaseating granulomatous disease of unknown etiology. The incidence is 11 per 100 000 white individuals and 34 per 100 000 black individuals. Cardiac involvement is seen in 2% to 5% of patients with systemic sarcoidosis and is often clinically undetected. This may be due to relative rarity of cardiac involvement, variability in presentation, or that there are no good clinical criteria for the diagnosis of cardiac sarcoidosis. Patients may be totally asymptomatic or have heart block, myocardial infarctions, heart failure, or sudden cardiac death, which may be due to involvement of the conduction system by sarcoidosis. We present a case of a 54-year-old black male with hypertension and hyperlipidemia. Prior to his death, he was witnessed to suddenly stand up, grab his chest, and collapse. His clinical cause of death was hypertensive and atherosclerotic cardiovascular disease. A retrospective review of autopsy cases over the last 23 years (1995-2018) at our institution (n = 6900) was undertaken. This case illustrates a rare disease and highlights the importance of complete autopsy even in patients who might otherwise be signed out as an external exam or records review only.

Primary Nonbacterial Thrombotic Endocarditis Presenting with Bowel Infarction Secondary to Superior Mesenteric Artery Embolism.

Nonbacterial thrombotic endocarditis (NBTE) is a rare antemortem diagnosis that is commonly associated with hypercoagulable states such as advanced malignancies, disseminated intravascular coagulation, and autoimmune diseases such as antiphospholipid syndrome and systemic lupus erythematosus. We present a case of a previously healthy 42-year-old man who presented with small bowel infarction caused by embolic occlusion of the superior mesenteric artery and was subsequently diagnosed with NBTE. Despite thorough investigation, efforts to find an underlying cause failed to reveal any associated systemic illnesses. This case report emphasizes the importance of further investigation into the possible underlying causes of NBTE, as it can manifest without any apparent systemic factors.

Utility of real-time three-dimensional echocardiography in improved assessment of a mitral valve papillary fibroelastoma.

Primary cardiac tumors are exceedingly rare. They are usually first identified by transthoracic echocardiography. However, transesophageal echocardiography (TEE), with the aid of real-time three-dimensional (3D) imaging, can provide additional important mass characteristics. We present a case that demonstrates the usefulness of 3D TEE in characterizing a papillary fibroelastoma.

The MET Receptor Tyrosine Kinase Confers Repair of Murine Pancreatic Acinar Cells following Acute and Chronic Injury.

Acinar cells represent the primary target in necroinflammatory diseases of the pancreas, including pancreatitis. The signaling pathways guiding acinar cell repair and regeneration following injury remain poorly understood. The purpose of this study was to determine the importance of Hepatocyte Growth Factor Receptor/MET signaling as an intrinsic repair mechanism for acinar cells following acute damage and chronic alcohol-associated injury. Here, we generated mice with targeted deletion of MET in adult acinar cells (MET-/-). Acute and repetitive pancreatic injury was induced in MET-/- and control mice with cerulein, and chronic injury by feeding mice Lieber-DeCarli diets containing alcohol with or without enhancement of repetitive pancreatic injury. We examined the exocrine pancreas of these mice histologically for acinar death, edema, inflammation and collagen deposition and changes in the transcriptional program. We show that MET expression is relatively low in normal adult pancreas. However, MET levels were elevated in ductal and acinar cells in human pancreatitis specimens, consistent with a role for MET in an adaptive repair mechanism. We report that genetic deletion of MET in adult murine acinar cells was linked to increased acinar cell death, chronic inflammation and delayed recovery (regeneration) of pancreatic exocrine tissue. Notably, increased pancreatic collagen deposition was detected in MET knockout mice following repetitive injury as well alcohol-associated injury. Finally, we identified specific alterations of the pancreatic transcriptome associated with MET signaling during injury, involved in tissue repair, inflammation and endoplasmic reticulum stress. Together, these data demonstrate the importance of MET signaling for acinar repair and regeneration, a novel finding that could attenuate the symptomology of pancreatic injury.

Induction of base excision repair enzymes NTH1 and APE1 in rat spleen following aniline exposure.

Mechanisms by which aniline exposure elicits splenotoxicity, especially a tumorigenic response, are not well-understood. Earlier, we have shown that aniline exposure leads to oxidative DNA damage and up-regulation of OGG1 and NEIL1/2 DNA glycosylases in rat spleen. However, the contribution of endonuclease III homolog 1 (NTH1) and apurinic/apyrimidinic endonuclease 1 (APE1) in the repair of aniline-induced oxidative DNA damage in the spleen is not known. This study was, therefore, focused on examining whether NTH1 and APE1 contribute to the repair of oxidative DNA lesions in the spleen, in an experimental condition preceding tumorigenesis. To achieve this, male SD rats were subchronically exposed to aniline (0.5 mmol/kg/day via drinking water for 30 days), while controls received drinking water only. By quantitating the cleavage products, the activities of NTH1 and APE1 were assayed using substrates containing thymine glycol (Tg) and tetrahydrofuran, respectively. Aniline treatment led to significant increases in NTH1- and APE1-mediated BER activity in the nuclear extracts of spleen of aniline-treated rats compared to the controls. NTH1 and APE1 mRNA expression in the spleen showed 2.9- and 3.2-fold increases, respectively, in aniline-treated rats compared to the controls. Likewise, Western blot analysis showed that protein expression of NTH1 and APE1 in the nuclear extracts of spleen from aniline-treated rats was 1.9- and 2.7-fold higher than the controls, respectively. Immunohistochemistry indicated that aniline treatment also led to stronger immunoreactivity for both NTH1 and APE1 in the spleens, confined to the red pulp areas. These results, thus, show that aniline exposure is associated with induction of NTH1 and APE1 in the spleen. The increased repair activity of NTH1 and APE1 could be an important mechanism for the removal of oxidative DNA lesions. These findings thus identify a novel mechanism through which NTH1 and APE1 may regulate the repair of oxidative DNA damage in aniline-induced splenic toxicity.

Induction of NEIL1 and NEIL2 DNA glycosylases in aniline-induced splenic toxicity.

The mechanisms by which aniline exposure elicits splenotoxic response, especially the tumorigenic response, are not well-understood. Earlier, we have shown that aniline-induced oxidative stress is associated with increased oxidative DNA damage in rat spleen. The base excision repair (BER) pathway is the major mechanism for the repair of oxidative DNA base lesions, and we have shown an up-regulation of 8-oxoguanine glycosylase 1 (OGG1), a specific DNA glycosylase involved in the removal of 8-hydroxy-2'-deoxyguanosine (8-OHdG) adducts, following aniline exposure. Nei-like DNA glycosylases (NEIL1/2) belong to a family of BER proteins that are distinct from other DNA glycosylases, including OGG1. However, contribution of NEIL1/2 in the repair of aniline-induced oxidative DNA damage in the spleen is not known. This study was, therefore, focused on evaluating if NEILs also contribute to the repair of oxidative DNA lesions in the spleen following aniline exposure. To achieve that, male SD rats were subchronically exposed to aniline (0.5 mmol/kg/day via drinking water for 30 days), while controls received drinking water only. The BER activity of NEIL1/2 was assayed using a bubble structure substrate containing 5-OHU (preferred substrates for NEIL1 and NEIL2) and by quantitating the cleavage products. Aniline treatment led to a 1.25-fold increase in the NEIL1/2-associated BER activity in the nuclear extracts of spleen compared to the controls. Real-time PCR analysis for NEIL1 and NEIL2 mRNA expression in the spleen revealed 2.7- and 3.9-fold increases, respectively, in aniline-treated rats compared to controls. Likewise, Western blot analysis showed that protein expression of NEIL1 and NEIL2 in the nuclear extract of spleens from aniline-treated rats was 2.0- and 3.8-fold higher than controls, respectively. Aniline treatment also led to stronger immunoreactivity for NEIL1 and NEIL2 in the spleens, confined to the red pulp areas. These studies, thus, show that aniline-induced oxidative stress is associated with an induction of NEIL1/2. The increased NIEL-mediated BER activity is another indication of aniline-induced oxidative damage in the spleen and could constitute another important mechanism of removal of oxidative DNA lesions, especially in transcribed DNA following aniline insult.

¹H and ³¹P NMR lipidome of ethanol-induced fatty liver.

BACKGROUND: Hepatic steatosis (fatty liver), an early and reversible stage of alcoholic liver disease, is characterized by triglyceride deposition in hepatocytes, which can advance to steatohepatitis, fibrosis, cirrhosis, and ultimately to hepatocellular carcinoma. In the present work, we studied altered plasma and hepatic lipid metabolome (lipidome) to understand the mechanisms and lipid pattern of early-stage alcohol-induced-fatty liver. METHODS: Male Fischer 344 rats were fed 5% alcohol in a Lieber-DeCarli diet. Control rats were pair-fed an equivalent amount of maltose-dextrin. After 1 month, animals were killed and plasma collected. Livers were excised for morphological, immunohistochemical, and biochemical studies. The lipids from plasma and livers were extracted with methyl-tert-butyl ether and analyzed by 750/800 MHz proton nuclear magnetic resonance (¹H NMR) and phosphorus (³¹P) NMR spectroscopy on a 600 MHz spectrometer. The NMR data were then subjected to multivariate statistical analysis. RESULTS: Hematoxylin and Eosin and Oil Red O stained liver sections showed significant fatty infiltration. Immunohistochemical analysis of liver sections from ethanol-fed rats showed no inflammation (absence of CD3 positive cells) or oxidative stress (absence of malondialdehyde reactivity or 4-hydroxynonenal positive staining). Cluster analysis and principal component analysis of ¹H NMR data of lipid extracts of both plasma and livers showed a significant difference in the lipid metabolome of ethanol-fed versus control rats. ³¹P NMR data of liver lipid extracts showed significant changes in phospholipids similar to ¹H NMR data. ¹H NMR data of plasma and liver reflected several changes, while comparison of ¹H NMR and ³¹P NMR data offered a correlation among the phospholipids. CONCLUSIONS: Our results show that alcohol consumption alters metabolism of cholesterol, triglycerides, and phospholipids that could contribute to the development of fatty liver. These studies also indicate that fatty liver precedes oxidative stress and inflammation. The similarities observed in plasma and liver lipid profiles offer a potential methodology for detecting early-stage alcohol-induced fatty liver disease by analyzing the plasma lipid profile.

Adenovirus-mediated overexpression of glutathione-s-transferase mitigates transplant arteriosclerosis in rabbit carotid allografts.

BACKGROUND: Cardiac transplant arteriosclerosis or cardiac allograft vasculopathy remains the leading cause of graft failure and patient death in heart transplant recipients. Endothelial cell injury is crucial in the development of human atherosclerosis and may play a role in allograft vasculopathy. Glutathione-S-transferase (GST) is known to protect endothelial cells from damage by oxidants and toxins. However, the contribution of human GST A4-4 (hGSTA4-4) to vascular cell injury and consequent transplant arteriosclerosis is unknown. METHODS: A recombinant adenoviral vector containing hGSTA4-4 gene was constructed and delivered to vascular endothelial cells in an in vivo rabbit carotid artery transplant model. Forty-five days after transplantation, allografts were harvested (n=28). Blood flow was measured by ultrasonography. In addition, grafts were analyzed by histology, morphometry, immunostaining, and western blot. RESULTS: The severity of arteriosclerosis in hGSTA4-4 transduced allografts was compared with control by measuring degree of stenosis by neointima. Decrease in blood flow in hGSTA4-4 transduced allografts was significantly less than control allografts, which also developed greater intimal thickening and stenosis than hGSTA4-4 transduced allografts in the proximal and distal regions of the graft. Leukocyte and macrophage infiltration was reduced in hGSTA4-4 transduced carotid arteries. CONCLUSION: Our data indicate that hGSTA4-4 overexpression protects the integrity of vessel wall from oxidative injury, and attenuates transplant arteriosclerosis.

Up-regulation of heme oxygenase-1 in rat spleen after aniline exposure.

The splenic toxicity of aniline is characterized by vascular congestion, hyperplasia, fibrosis, and the development of a variety of sarcomas in rats. However, the underlying mechanisms by which aniline elicits splenotoxic response are not well understood. Previously we have shown that aniline exposure causes oxidative damage to the spleen. To further explore the oxidative mechanism of aniline toxicity, we evaluated the potential contribution of heme oxygenase-1 (HO-1), which catalyzes heme degradation and releases free iron. Male SD rats were given 1 mmol/kg/day aniline in water by gavage for 1, 4, or 7 days, and respective controls received water only. Aniline exposure led to significant increases in HO-1 mRNA expression in the spleen (2-and 2.4-fold at days 4 and 7, respectively) with corresponding increases in protein expression, as confirmed by ELISA and Western blot analysis. Furthermore, immunohistochemical assessment of spleen showed stronger immunostaining for HO-1 in the spleens of rats treated for 7 days, confined mainly to the red pulp areas. No changes were observed in mRNA and protein levels of HO-1 after 1 day exposure. The increase in HO-1 expression was associated with increases in total iron (2.4-and 2.7-fold), free iron (1.9-and 3.5-fold), and ferritin levels (1.9-and 2.1-fold) at 4 and 7 days of aniline exposure. Our data suggest that HO-1 up-regulation in aniline-induced splenic toxicity could be a contributing pro-oxidant mechanism, mediated through iron release, and leading to oxidative damage.

Development and characterization of a novel in vivo model of carcinoid syndrome.

PURPOSE: Carcinoid syndrome, characterized by flushing, diarrhea, and valvular heart disease, can occur following carcinoid tumor metastasis to the liver and systemic release of bioactive hormones into the systemic circulation. Treatment of this devastating disease is hampered by the lack of an in vivo model that recapitulates the clinical syndrome. EXPERIMENTAL DESIGN: Here, we have injected BON cells, a novel human carcinoid cell line established in our laboratory, into the spleens of athymic nude mice to establish liver metastases. RESULTS: The majority of mice injected intrasplenically with BON cells developed significant increases in plasma serotonin and urine 5-hydroxyindoleacetic acid, and several mice exhibited mesenteric fibrosis, diarrhea, and fibrotic cardiac valvular disease reminiscent of carcinoid syndrome by both echocardiographic and histopathologic evaluation. Mice pretreated with octreotide, a long-acting somatostatin analogue, or bevacizumab, a vascular endothelial growth factor inhibitor, developed fewer liver metastases and manifestations of carcinoid syndrome, including valvular heart disease. CONCLUSION: We have provided an important in vivo model to further delineate novel treatment modalities for carcinoid syndrome that will also be useful to elucidate the factors contributing to the sequelae of carcinoid disease (e.g., mesenteric fibrosis and valvular heart disease).

Oxidative DNA damage and its repair in rat spleen following subchronic exposure to aniline.

The mechanisms by which aniline exposure elicits splenotoxic response, especially the tumorigenic response, are not well-understood. Splenotoxicity of aniline is associated with iron overload and generation of reactive oxygen species (ROS) which can cause oxidative damage to DNA, proteins and lipids (oxidative stress). 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is one of the most abundant oxidative DNA lesions resulting from ROS, and 8-oxoguanine glycosylase 1 (OGG1), a specific DNA glycosylase/lyase enzyme, plays a key role in the removal of 8-OHdG adducts. This study focused on examining DNA damage (8-OHdG) and repair (OGG1) in the spleen in an experimental condition preceding a tumorigenic response. To achieve that, male Sprague-Dawley rats were subchronically exposed to aniline (0.5 mmol/kg/day via drinking water for 30 days), while controls received drinking water only. Aniline treatment led to a significant increase in splenic oxidative DNA damage, manifested as a 2.8-fold increase in 8-OHdG levels. DNA repair activity, measured as OGG1 base excision repair (BER) activity, increased by approximately 1.3 fold in the nuclear protein extracts (NE) and approximately 1.2 fold in the mitochondrial protein extracts (ME) of spleens from aniline-treated rats as compared to the controls. Real-time PCR analysis for OGG1 mRNA expression in the spleen revealed a 2-fold increase in expression in aniline-treated rats than the controls. Likewise, OGG1 protein expression in the NEs of spleens from aniline-treated rats was approximately 1.5 fold higher, whereas in the MEs it was approximately 1.3 fold higher than the controls. Aniline treatment also led to stronger immunostaining for both 8-OHdG and OGG1 in the spleens, confined to the red pulp areas. It is thus evident from our studies that aniline-induced oxidative stress is associated with increased oxidative DNA damage. The BER pathway was also activated, but not enough to prevent the accumulation of oxidative DNA damage (8-OHdG). Accumulation of mutagenic oxidative DNA lesions in the spleen following exposure to aniline could play a critical role in the tumorigenic process.

Peri-operative alemtuzumab (Campath-1H) and plasmapheresis for high-PRA positive lymphocyte crossmatch heart transplant: a strategy to shorten left ventricular assist device support.

Patients on a left ventricular assist device (LVAD) often have a high level of panel-reactive antibodies (PRA). Conventional therapy is to await a heart from a negative prospective-crossmatch donor. We transplanted three high-PRA patients with non-crossmatched hearts, using intra- and post-operative plasmapheresis and long-term T-/B-/plasma-cell therapy with alemtuzumab. Three highly sensitized patients (70%, 94% and 96% T-PRA; 63%, 24% and 73% B-PRA) were transplanted after 29, 187 and 94 days LVAD support. The first patient (Case 1) had an erroneous prospective negative crossmatch (due to an outside laboratory's use of the wrong patient's serum) with immediate allograft dysfunction. The correct serum showed a strongly positive crossmatch; plasmapheresis followed by alemtuzumab (20 mg intravenously) shortly after arrival in the ICU resulted in rapid hemodynamic improvement. Encouraged by this success, the next two patients (Cases 2 and 3) underwent LVAD explant and heart transplant with the next available ABO-identical, non-crossmatched donors, using plasmapheresis on bypass immediately before heart implant and alemtuzumab 20 mg intravenously upon ICU arrival, with uneventful courses. All three patients had positive retrospective T- and B-cell crossmatches. Maintenance immunosuppression consisted of cyclosporine and routine prednisone taper, with plasmapheresis as needed (Patient 1, x10; Patient 2, x5) based on diastolic dysfunction. Mycophenolate mofetil was started as a third agent several months post-transplant. Patients are presently New York Heart Association (NYHA) Class I at 26, 16 and 13 months post-transplant. In this small series with follow-up, immediate antibody removal with plasmapheresis, combined with alemtuzumab, a long-acting antibody to CD52 (expressed on T, B and some plasma cells), appears effective in allowing transplantation in sensitized, positive crossmatch recipients. Expanded use of this strategy could shorten LVAD support in many sensitized patients.

Cardiac preconditioning with local laser-induced hyperthermia.

BACKGROUND: Whole body hyperthermia has been shown to be highly effective in preconditioning cardiac tissue against reperfusion injury. The current study was aimed to assess the ability of regional sublethal laser-induced hyperthermia to precondition cardiac tissue against ischemic-induced myocardial infarction. METHODS AND RESULTS: Diode laser radiation was used to locally heat (42 degrees C) the left ventricle by irradiating the epicardial surface of rat heart for 20 min. As control, another group of animals were treated with whole-body hyperthermia (WBH) for 20 min. After a 4-h recovery period, the left coronary artery was occluded for 30 min followed by 4 h of reperfusion. A significant degree of reduction in infarct size as assessed by percent of at-risk area was observed in animals that were subjected to laser-induced local hyperthermia (15.4 +/- 3.1; n = 5) versus the sham group (49.8 +/- 6.6; n = 5). The degree of cardiac protection induced by local hyperthermia was similar to the protection observed when the animals were preconditioned with WBH. Furthermore, regional laser-induced hyperthermia and WBH induced similar degree of up-regulation of heat shock protein 70 in cardiac tissue. Regional hyperthermia up-regulated heat shock protein in regions of the heart beyond that directly subjected to laser-induced heat stress. CONCLUSION: Sublethal local heating of the heart with diode laser irradiation can improve myocardial salvage and may provide a practical approach for tissue preconditioning against reperfusion injury.

Chronic exposure to trichloroethene causes early onset of SLE-like disease in female MRL +/+ mice.

Trichloroethene (TCE) exacerbates the development of autoimmune responses in autoimmune-prone MRL +/+ mice. Although TCE-mediated autoimmune responses are associated with an increase in serum immunoglobulins and autoantibodies, the underlying mechanism of autoimmunity is not known. To determine the progression of TCE-mediated immunotoxicity, female MRL +/+ mice were chronically exposed to TCE through the drinking water (0.5 mg/ml of TCE) for various periods of time. Serum concentrations of antinuclear antibodies increased after 36 and 48 weeks of TCE exposure. Histopathological analyses showed lymphocyte infiltration in the livers of MRL +/+ mice exposed to TCE for 36 or 48 weeks. Lymphocyte infiltration was also apparent in the pancreas, lungs, and kidneys of mice exposed to TCE for 48 weeks. Immunoglobulin deposits in kidney glomeruli were found after 48 weeks of exposure to TCE. Our results suggest that chronic exposure to TCE promotes inflammation in the liver, pancreas, lungs, and kidneys, which may lead to SLE-like disease in MRL +/+ mice.

Cellular differentiation in three-dimensional lung cell cultures.

INTRODUCTION: Aspects of human biology that are not sufficiently addressed by current cell culture models are cellular differentiation and three-dimensional (3-D) structural organization. A model that more closely associates the presence and biology of organelles to molecular expressions relevant to these organelles may provide evidence of cellular differentiation and the beginning steps in the construction of a 3-D architecture. The development of a new model--3-D cell cultures--may ultimately provide a better understanding of lung biology and pathobiology. PURPOSE: The purpose of this study was to develop both traditional monolayer and 3-D cell cultures of a known and well documented normal lung cell line and then to determine similarities and differences between these cultures in terms of differentiation and molecular marker expression. RESULTS: Electron microscopy identified presence of lipid inclusion, microvilli, extra cellular matrix, and tight junctions in the 3-D cultures; differentiation not seen in ML cultures. The degree of differentiation determined by immunohistochemistry when the cell line was grown as ML or 3-D cultures shows that ultra-structure and marker expressions were more representative of control tissue than when cells were grown in 3-D than as MLs. METHODS: An immortalized cell line was grown as a traditional monolayer (ML) in culture flasks and as 3-D cultures in rotating walled vessels and incubated under identical conditions. Comparison for presence of differentiation and marker expression between these cultures and control tissue collected from surgical patient specimens was studied. Electron microscopy for identification of ultra structures, and immunohistochemistry (ZO-1, EMA, ICAM-1, villin, tubulin, CK 18, VWF, Collagen IV and human mucin) for phenotypic comparisons between cells in ML and 3-D cell cultures was conducted. SUMMARY: The development of 3-D cell cultures will provide for a new and more powerful tool in the study of lung biology and pathobiology.

Regression of lung and colon cancer xenografts by depleting or inhibiting RLIP76 (Ral-binding protein 1).

Ral-binding protein 1 (RALBP1) is a stress-responsive and stress-protective multispecific transporter of glutathione conjugates (GS-E) and xenobiotic toxins. It is frequently overexpressed in malignant cells and plays a prominent antiapoptotic role selectively in cancer cells through its ability to control cellular concentration of proapoptotic oxidized lipid byproducts. In the absence of chemotherapy, depletion or inhibition of RALBP1 causes regression of syngeneic mouse B16 melanoma. Because RALBP1 transports anthracycline and Vinca alkaloid drugs, as well as GS-E, and because it confers resistance to these drugs, we proposed that depletion or inhibition of RALBP1 should cause regression of human solid tumors that overexpress RALBP1 and augment chemotherapy efficacy. Non-small-cell lung cancer (NSCLC) H358 and H520 and colon SW480 cell lines were used. Cytotoxic synergy between anti-RALBP1 immunoglobulin G (IgG), cis-diammine-dichloroplatinum (II) [CDDP], and vinorelbine was examined in cell culture and xenografts of NSCLC cells. Effects of RALBP1 depletion by antisense were examined in xenografts of NSCLC H358, NSCLC H520, and colon SW480 cells. RALBP1 depletion by phosphorothioate antisense was confirmed and was associated with rapid, complete, and sustained remissions in established s.c. human lung and colon xenografts. RALBP1 inhibition by anti-RALBP1 IgG was equally as effective as antisense and enhanced CDDP-vinorelbine in lung cancer xenografts. These studies show that RALBP1 is a transporter that serves as a key effector function in cancer cell survival and is a valid target for cancer therapy, and confirm that inhibitory modulation of RALBP1 transport activity at the cell surface is sufficient for antitumor effects.