Mitsuaki Isobe

Comparison of clinical features and prognosis of cardiac sarcoidosis and idiopathic dilated cardiomyopathy

In the present study, clinical findings of 15 patients with cardiac sarcoidosis presenting as dilated cardiomyopathy were compared with those of 30 consecutive patients with idiopathic dilated cardiomyopathy. The sarcoidosis patients had different clinical features, including female predominance, a high incidence of grave conduction disturbance and abnormal wall thickness, uneven wall motion abnormalities, and perfusion defects preferentially affecting the anteroseptal and apical regions, and poor prognosis compared with those with idiopathic dilated cardiomyopathy.

Iodine-123 Metaiodobenzylguanidine Scintigraphic Assessment of Myocardial Sympathetic Innervation in Patients With Familial Amyloid Polyneuropathy☆

OBJECTIVES This study attempted to assess myocardial sympathetic innervation using iodine-123 (I-123) metaidobenzylguanidine (MIBG) imaging in patients with familial amyloid polyneuropathy. BACKGROUND Signs and symptoms of cardiac autonomic dysfunction are commonly seen in patients with cardiac amyloidosis. However, the incidence and magnitude of abnormalities in myocardial sympathetic nerve function by means of I-123 MIBG imaging and their relation to clinical findings, cardiac function and the results of thallium-201 (Tl-201) and technetium-99m pyrophosphate (Tc-99m PYP) myocardial scanning have not yet been clarified. METHODS We performed M-mode, two-dimensional and Doppler echocardiography and I-123 MIBG, Tl-201 and Tc-99m PYP imaging of the heart in 12 patients with familial amyloid polyneuropathy and biopsy-proved cardiac amyloidosis. RESULTS Ten of 12 patients had no clinical evidence of overt heart disease, but left ventricular (LV) wall thickening was observed in 4 of these 10. Left ventricular percent fractional shortening and Doppler transmitral flow velocity patterns were found to be normal in all 12 patients. Eight of 12 patients showed no myocardial MIBG accumulation, with limited uptake in the remaining 4 demonstrated only in the LV anterior wall. Diffuse but mild myocardial uptake of Tc-99m PYP occurred in only 4 of 12 patients, and all 12 had normal results on Tl-201 myocardial scanning. Complete defects on myocardial MIBG scans were found in five of eight patients with negative findings on Tc-99m PYP myocardial scanning. The incidence and magnitude of myocardial uptake of MIBG were independent of clinical findings, extent of endomyocardial amyloid deposition, electrocardiographic QRS voltage and ventricular wall thickness. CONCLUSIONS Patients with familial amyloid polyneuropathy show a high incidence of myocardial adrenergic denervation with viable myocardium that can be identified very early in cardiac amyloidosis, before the development of clinically apparent heart disease, ventricular wall thickening, significant LV systolic and diastolic dysfunction and positive findings on Tc-99m PYP myocardial scanning.

Gene Therapy for Attenuating Cardiac Allograft Arteriopathy Using Ex Vivo E2F Decoy Transfection by HVJ-AVE–Liposome Method in Mice and Nonhuman Primates

Cardiac allograft arteriopathy, which limits the long-term survival of recipients, is characterized by diffuse intimal thickening composed of proliferative smooth muscle cells. The transcription factor E2F plays a pivotal role in the coordinated transcription of cell-cycle regulatory genes. To test the hypothesis that double-stranded DNA with specific affinity for E2F (E2F decoy) is effective in preventing intimal hyperplasia, we performed ex vivo single intraluminal delivery of E2F decoy into cardiac allografts of mice and Japanese monkeys using the hemagglutinating virus of Japan (HVJ) artificial viral envelope–liposome method. In murine models, antisense cyclin-dependent kinase 2 (cdk2) kinase oligodeoxynucleotide (ODN) and no transfers were performed to compare the effects. Severe intimal thickening was observed, and multiple cell-cycle regulatory genes were enhanced in untreated allografts. E2F decoy prevented neointimal formation and suppressed these genes for up to 8 weeks, whereas antisense cdk2 kinase ODN had limited effects. In primate models, E2F decoy dramatically prevented neointimal thickening and suppressed multiple cell-cycle regulatory genes, whereas intimal thickening developed in the nontransfected or mismatch decoy-transfected allografts. Gel mobility shift assay proved the specific effects of E2F decoy, and reverse transcriptase–polymerase chain reaction documented that neither complication nor dissemination of HVJ into other organs was observed. We demonstrate that ex vivo gene delivery to allografts is a potent strategy to modify allograft gene expression, resulting in prevention of graft arteriopathy without systemic adverse effects.

Early complement system activation and neutrophil priming in acute pancreatitis: Participation of trypsin

BACKGROUND It is known that the pancreatic enzyme trypsin can cleave components of the complement system, producing the chemokines C3a and C5a. In the setting of experimental acute pancreatitis, we analyzed the contribution of serum trypsin to systemic complement activation and its importance in neutrophil lung sequestration, an early event in acute pancreatitis. METHODS Cerulein was infused into Lewis rats to produce mild edematous acute pancreatitis. Soluble complement receptor, sCR1, was used to block complement activation. RESULTS Induction of acute pancreatitis was confirmed by the serum levels of amylase and trypsin and by histologic studies. A correlation was found between serum total complement activity and the trypsin level (r = -0.884). Whole lung tissue myeloperoxidase activity was high in rat lungs at t = 4 hours, indicating accumulation of neutrophils. The sCR-1-treated group showed significantly lower levels. Flow cytometry of neutrophils incubated with serum from rats with pancreatitis showed significantly higher CD11b/CD18 expression than that after incubation with serum from control or sCR-1-treated rats. Until t = 12 hours, no change in the lung wet to dry weight ratio or bronchoalveolar fluid cytology was observed, indicating no functional enhancement of neutrophils that had accumulated in the lungs. CONCLUSIONS The present results demonstrate the important role of trypsin in systemic complement activation early in the course of acute pancreatitis. The resulting central production of chemotaxins causes priming of circulating neutrophils and subsequent lung sequestration. These events can be at least partially reversed by sCR-1 treatment.

Antisense Bcl-x oligonucleotide induces apoptosis and prevents arterial neointimal formation in murine cardiac allografts

OBJECTIVE Cardiac allograft arteriosclerosis, which limits long-term survival of recipients, cannot be prevented by conservative therapies. The arteriopathy is characterized by diffuse intimal thickening comprised of proliferative smooth muscle cells (SMCs). Cell death is a prominent feature of atherosclerosis; Bcl-x is one of the anti-apoptotic mediators. METHODS To test the hypothesis that antisense bcl-x oligodeoxynucleotide (ODN) is effective in preventing intimal hyperplasia through enhancing apoptosis after cardiac transplantation, we performed single intraluminal delivery of antisense bcl-x ODN into murine cardiac allografts (n = 9). DBA/2 (H-2d) hearts were transplanted into B10.D2 (H-2d) mice. Sense bcl-x ODN (n = 8) and no treatment (n = 8) studies were also performed. RESULTS Allografts were harvested at 4 weeks after transplantation; all allografts kept beating throughout the period. Coronary intimal thickening had developed in nontreated and sense ODN transfected allografts at 4 weeks after transplantation with enhanced expression of Bcl-x and cell adhesion molecules, and suppressed apoptosis. However, antisense bcl-x ODN prevented neointimal formation through enhanced apoptosis. CONCLUSION These results indicate that apoptosis of vascular SMCs induced by Bcl-x is associated with initial hyperplasia after heart transplantation. Antisense bcl-x ODN inhibits SMC proliferation by inducing apoptosis in graft coronary arteries.

Effects of intracellular cyclic AMP modulators on human eosinophil survival, degranulation and CD11b expression.

Background: Brochial asthma is characterized by infiltration of inflammatory cells such as lymphocytes and eosinophils. Theophylline is one of the most widely used drugs in the therapy of bronchial asthma, and phosphodiesterase (PDE) inhibition is thought to be an important mechanism of its anti–inflammatory actions. However, the detailed effects of PDE inhibition on eosinophils still remain unclear. Methods: Eosinophils in peripheral blood obtained from normal subjects and patients with mild off–season allergic rhinitis were purified using CD16 negative selection. The following effects of theophylline (nonselective PDE inhibitor), KF19514 (selective PDE IV inhibitor), mirlinone (selective PDE III inhibitor), procaterol (β2–adrenoceptor agonist) and N6, 2′–O–dibutyryladenosine 3′5′–cyclic monophosphate (dB–cAMP; AMP analogue) on eosinophils were examined: (1) survival in the presence of interleukin–5, (2) degranulation by granulocyte/macrophage colony–stimulating factor (GM–CSF) or platelet–activating factor (PAF), (3) CD11b expression under GM–CSF or PAF stimulation and (4) intracellular cAMP level. Results: Eosinophil survival was inhibited by theophilline, KF19514 or procaterol. GM–CSF– or PAF–induced degranulation was inhibited by theophylline, KF19514, procaterol or dB–cAMP. CD11b up–regulation by PAF was inhibited by theophylline, KF19514 or dB–cAMP, while GM–CSF–stimulated CD11b up–regulation was not significantly inhibited by any of the drugs tested. The levels of intracellular cAMP were increased by theophylline, KF19514 and procaterol. Conclusions: Intracellular cAMP is an important factor in the regulation of eosinophil biological functions. PDE IV inhibitors and β2–agonists are suggested to be useful for the treatment of bronchial asthma through inhibition of eosinophil effector function.

Improvement of eosinophilic heart disease after steroid therapy: successful demonstration by endomyocardial biopsied specimens.

SummaryA 62-year-old man with acute eosinophilic endomyocarditis developed congestive heart failure. The biopsy specimens revealed degranulated eosinophils and eosinophil cationic protein (ECP) in the endocardium, and in activated eosinophils and the myocardial interstitium. On electronmicroscopy, a characteristic cardiac myocytolytic change showing disruption at the intercellular junctional site was observed. After steroid treatment, clinical symptoms, systolic dysfunction and laboratory data dramatically improved. In the subsequent biopsy specimens, eosinophilic infiltration and ECP disappeared. Steroid therapy provided a beneficial effect in preventing the progression of cardiac damage. This effect was clearly documented by histochemical studies of the serial endomyocardial biopsy samples.

Expression of vascular endothelial growth factor and angiogenesis in cardiac myxoma: A study of fifteen patients

OBJECTIVE To clarify the association between angiogenesis and the clinicopathologic features in cardiac myxoma, vascular endothelial growth factor expression in the myxoma was examined by using reverse transcriptase polymerase chain reaction and immunohistochemistry, and the microvessel density was determined by counting microvessels in the myxoma by using immunostaining for platelet endothelial cell adhesion molecule 1. METHODS Seven fresh-frozen and 15 formalin-embedded tissues were analyzed by means of reverse transcriptase polymerase chain reaction and immunostaining for vascular endothelial growth factor, respectively. The microvessel density was measured in the 15 formalin-embedded tissues. Furthermore, immunostaining for proliferating cell nuclear antigen was performed, and the proliferating cell nuclear antigen-labeling index was calculated. RESULTS All of the 7 analyzed myxomas were positive for vascular endothelial growth factor messenger RNA, as determined by means of reverse transcriptase polymerase chain reaction, whereas atrial septum and atrium tissues were negative. Positive immunohistochemical reaction for vascular endothelial growth factor was observed in the cells of all 15 myxomas. The size of myxomas with high vascular endothelial growth factor expression was smaller than that of myxomas with low vascular endothelial growth factor expression. The microvessel density in myxomas with high vascular endothelial growth factor expression was higher than that in myxomas with low vascular endothelial growth factor expression. There was an inverse correlation between the tumor size and the ratio of the microvessel density in the central part to the microvessel density in the peripheral part of myxomas. Furthermore, there was an inverse correlation between the proliferating cell nuclear antigen-labeling index and the tumor size, and the prolferating cell nuclear antigen-labeling index in myxomas with high vascular endothelial growth factor expression was higher than that in myxomas with low vascular endothelial growth factor expression. CONCLUSIONS Cardiac myxomas produce vascular endothelial growth factor, which probably induces angiogenesis for tumor growth.

The role of cell adhesion molecules in allograft rejection after penetrating keratoplasty in mice. Clinical and immunohistochemical study.

Abstract• Background: It has been reported that adhesion molecules play an important role in immunological rejection after organ transplantation. In the present study, we examined the role of ICAM-1/LFA-1 adhesion molecules in corneal allograft rejection and evaluated the immunological specificity of monoclonal antibodies (mAbs) in preventing allograft rejection in mice. • Methods: The allografted mice were intraperitoneally injected with 100 μg/day of the following mAbs: a control mAb, anti-ICAM-1 mAb, anti-LFA-1 mAb, or a mixture of anti-ICAM-1 and anti-LFA-1 mAbs from 1 day before to 7 days after surgery. The expression of ICAM-1 and LFA-1 molecules in the grafted cornea was studied immunohistochemically. The corneas from a syngeneic donor or a third-party strain were transplanted 4 weeks after the initial keratoplasty onto the mice treated with both anti-ICAM-1 and anti-LFA-1 mAbs. • Results: The allografts treated with anti-LFA-I mAb alone or both anti-ICAM-1 and anti-LFA-1 mAbs remained transparent for more than 2 weeks, and the survival rate at 8 weeks was 40% in both groups. ICAM-1 was expressed on the mononuclear cells, keratocytes and endothelial cells in the allografts without treatment. The second corneal grafts syngeneic to the initial donor remained transparent at 2 weeks, whereas those from the third party were rejected. • Conclusions: ICAM-1 and LFA-1 adhesion molecules play a crucial role in the pathophysiology of corneal transplant rejection. The immunosuppressive effects of anti-ICAM-1 and anti-LFA-1 mAbs are highly allospecific. The administration of mAbs to the adhesion molecules represents a new means of suppressing allograft rejection after penetrating keratoplasty.

Intercellular adhesion molecule-1 on eosinophils is involved in eosinophil protein X release induced by cytokines.

Recent evidence suggests that adhesion molecules play important roles in eosinophil functions such as degranulation and superoxide anion production. CD11b/CD18 (Mac‐1) and CD49d/CD29 (VLA‐4) are involved in eosinophil–endothelial adhesion through their counterligands, intercellular adhesion molecule‐1 (ICAM‐1; CD54) and vascular cell adhesion molecule‐1 (VCAM‐1), respectively. CD54 is also induced on eosinophils by cytokine stimulation. We hypothesized that CD54 on human eosinophils may participate in eosinophil degranulation. CD54 was induced on eosinophils by a combination of human recombinant granulocyte–macrophage colony‐stimulating factor (rGM‐CSF) and human recombinant tumour necrosis factor‐α (rTNF‐α) within 2 hr of incubation, as determined by flow cytometric analysis. Recombinant GM‐CSF alone induced a slight but significant CD54 expression on eosinophils. Release of eosinophil protein X, an indicator of eosinophil degranulation, was induced by rGM‐CSF and this effect was synergistically enhanced by adding rTNF‐α. To determine the role of newly expressed CD54 in eosinophil degranulation, a blocking assay was performed using monoclonal antibody (mAb) against CD54 and CD18. Anti‐CD18 mAb and anti‐CD54 mAb markedly inhibited eosinophil degranulation induced by rGM‐CSF or a combination of rGM‐CSF and rTNF‐α. On the other hand, anti‐CD54 mAb had little effect on rGM‐CSF‐ or rGM‐CSF/rTNF‐α‐induced adhesion of eosinophils, whereas anti‐CD18 mAb significantly inhibited eosinophil adhesion. These results indicate that CD54 on eosinophils plays an important role in the eosinophil degranulation and that eosinophils are capable of interacting with other β2 integrin‐positive cells.