Peripheral follicular cytotoxic T -like cells in Kawasaki disease with coronary artery aneurysms: A case report

INTRODUCTION

Kawasaki disease (KD) is the leading cause of acquired heart abnormalities during childhood. The infiltration of CD8+ T cells plays an essential role in the formation of coronary aneurysms. Follicular cytotoxic T (Tfc) cells are a newly defined subset of CD8+ T cells that express CXC-chemokine receptor 5. The role of Tfc cells in KD is unclear. However, in this report, we present 2 KD children with sustained coronary artery aneurysms (CAA), and we found that their peripheral C-X-C Chemokine Receptor 5+ T cells contained quite amounts of CD4 negative cells. Importantly, these cells have never been reported in KD.

PATIENTS CONCERNS

Case 1 was a 3-year-old boy with a complaint of continuous fever for 6 days and conjunctival injection for 3 days. Case 2 was a 6-month-old boy who was hospitalized because of persistent fever for 5 days, rashes and conjunctival injection for 1 day.

DIAGNOSIS

Case 1 was diagnosed with KD according to typical symptoms and signs including fever over 5 days, conjunctival injection, rashes, swelling cervical lymph nodes and a strawberry tongue. Case 2 had atypical symptoms including persistent fever for 5 days, rashes and conjunctival injection, and he was diagnosed with KD based on the echocardiographic findings.

INTERVENTION

Both the 2 patients received intravenous immunoglobulin and oral aspirin. Besides, case 1 was given the second infusion of intravenous immunoglobulin, intravenous prednisolone and low-molecular-weight heparin.

OUTCOMES

The CAA of case 1 did not regress until the 12th month after disease onset. The CAA of patient 2 began to regress at the third month after disease onset. During the months from disease onset to the recent follow-up, no cardiovascular events had occurred.

CONCLUSIONS

We speculate that Tfc cells may be associated with the formation of CAA. Further studies with larger sample size and functional analysis of these cells are needed.

Resistin Enhances Inflammatory Cytokine Production in Coronary Artery Tissues by Activating the NF-κB Signaling

Purpose. Kawasaki disease (KD) is a systemic vasculitis and is a leading cause of coronary artery lesions (CALs) in childhood. Our previous study has shown higher levels of serum Resistin in KD patients with coronary aneurysm. This study aimed at examining the association of Resistin with inflammatory cytokine expression in mouse model of coronary arteritis and determining the potential mechanisms. Methods. C57BL/6 mice were injected with Lactobacillus cell wall extract (LCWE) to induce coronary arteritis. The relative levels of Resistin, TNF-α, IL-1β, and MMP-9 expression and inflammatory infiltrates in the coronary arteries were determined longitudinally by quantitative RT-PCR, ELISA, and histology. The effect of TLR4 and NF-κB activation on Resistin-induced TNF-α and IL-1β expression in human coronary artery endothelium cells (HCAECs) was examined by quantitative RT-PCR. Results. Higher levels of Resistin, TNF-α, IL-1β, and MMP-9 expression were associated with the degrees of inflammatory infiltrates in the coronary artery walls of the LCWE-injected mice. Resistin enhanced TNF-α and IL-1β expression in HCAECs at 18 or 24 hours after stimulation. Pretreatment with anti-TLR4 attenuated Resistin-enhanced IL-1β, but not TNF-α, expression and pretreatment with parthenolide or QNZ demolished Resistin-enhanced TNF-α expression in HACECs. Pretreatment with parthenolide, but not QNZ, blocked Resistin-enhanced IL-1β expression in HCAECs. Conclusion. Resistin may enhance inflammation by cross-talking with TLR4/NF-κB signaling during the development of coronary arteritis in mice.

Coronary artery aneurysm induced by Kawasaki disease in children show features typical senescence

BACKGROUND

Kawasaki disease (KD) causes coronary artery disease (CAD) in children. In addition, a history of KD is suspected to be a risk factor for the development of atherosclerotic heart disease in the future. Histological senescence changes are a common denominator in atherosclerotic lesions in adults, so the present study investigated whether histological senescence changes had already occurred in KD aneurysm.

METHODS AND RESULTS

KD coronary aneurysms and internal mammary arteries retrieved from 5 children with KD (3, 4, 5, 6, and 11 years old, respectively) who underwent coronary artery bypass grafting, as well as giant coronary aneurysm size-reducing operations, were analyzed. Senescence-associated strong beta-galactosidase activity was observed in KD aneurysms, but not in the internal mammary arteries. An immunohistochemical analysis of the KD aneurysm using anti-CD31, anti-endothelial nitric oxide synthetase (eNOS), anti-vascular adhesion molecule-1 (VCAM-1), and anti-monocyte chemoattractant protein-1 (MCP-1) showed vascular endothelium CD31 staining, decreased staining of eNOS and strong staining of MCP-1 and VCAM-1. cDNA microarray gene expression profiling revealed increased MCP-1 expression in the KD aneurysm, a finding confirmed by quantitative polymerase chain reaction.

CONCLUSIONS

Histological features of senescence and active remodeling gene expression show that the KD aneurysm is not a silent vasculitis terminal. The future fate of KD aneurysms, including atherosclerosis, should be monitored carefully.

TNF-alpha is necessary for induction of coronary artery inflammation and aneurysm formation in an animal model of Kawasaki disease

Kawasaki disease is the most common cause of multisystem vasculitis in childhood. The resultant coronary artery lesions make Kawasaki disease the leading cause of acquired heart disease in children in the developed world. TNF-alpha is a pleiotropic inflammatory cytokine elevated during the acute phase of Kawasaki disease. In this study, we report rapid production of TNF-alpha in the peripheral immune system after disease induction in a murine model of Kawasaki disease. This immune response becomes site directed, with migration to the coronary arteries dependent on TNF-alpha-mediated events. Production of TNF-alpha in the heart is coincident with the presence of inflammatory infiltrate at the coronary arteries, which persists during development of aneurysms. More importantly, inflammation and elastin breakdown in the coronary vessels are completely eliminated in the absence of TNF-alpha effector functions. Mice treated with the TNF-alpha-blocking agent etanercept, as well as TNFRI knockout mice, are resistant to development of both coronary arteritis and coronary aneurysm formation. Taken together, TNF-alpha is necessary for the development of coronary artery lesions in an animal model of Kawasaki disease. These findings have important implications for potential new therapeutic interventions in children with Kawasaki disease.

Angiogenesis in fatal acute Kawasaki disease coronary artery and myocardium

Angiogenesis has been shown to be dysregulated in coronary artery (CA) aneurysms in the chronic phase of Kawasaki disease (KD). Neovascularization may occur in inflammatory-related vascular diseases because many angiogenesis mediators are secreted by inflammatory cells. We hypothesized that inflammation of the acute KD CA aneurysm could lead to dysregulation of angiogenesis mediators and subsequent neovascularization. To investigate this hypothesis, acute fatal KD cardiac tissues were immunostained for angiogenic inducers and inhibitors. Microvessel density was determined and the degree of inflammation assessed. Marked inflammation and angiogenesis were found in acute KD CA aneurysms and myocardium, with the highest microvessel density seen in patients who died 2-3 weeks after onset of the disease. Expression of proangiogenic proteins was higher than expression of inhibitors in KD CA aneurysms and myocardium. Angiogenesis mediators were localized to inflammatory cells in the myointima, adventitia, and myocardium. We conclude that significant neovascularization occurs in acute KD CA aneurysms and myocardium much sooner after onset of the disease than has been previously reported, that multiple angiogenesis factors are involved, and that dysregulation of angiogenesis likely contributes to KD vasculopathy.

Cell adhesion molecule expression in coronary artery aneurysms in acute Kawasaki disease

BACKGROUND

The pathogenesis of coronary artery aneurysm (CAA) formation in acute Kawasaki disease (KD) remains unclear. Cell adhesion molecules mediate cell-cell and cell-matrix interactions and regulate leukocyte migration, angiogenesis and tissue remodeling. We hypothesized that cell adhesion molecules are expressed in acute KD CAA.

METHODS

: P-selectin, E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and integrin beta1 were immunolocalized in coronary arteries from 6 acute KD patients and 7 controls.

RESULTS

In endothelial cells of adventitial neovasculature in KD CAA, P-selectin and integrin beta1 were expressed in all of 6 patients, and E-selectin and/or VCAM-1 were expressed in 4 of 6. Endothelial cells in controls and in nonaneurysmal KD coronary arteries expressed P-selectin and integrin beta1, but not E-selectin or VCAM-1. Integrin beta1 was expressed on infiltrating leukocytes in 5 of 6 KD CAA and on fibroblasts in 6 of 6; these findings were absent in controls and in nonaneurysmal KD coronary arteries.

CONCLUSIONS

The lack of widespread expression of E-selectin or VCAM-1 on endothelial cells of acute KD coronary arteries was surprising and suggests that inflammatory cell infiltration into KD coronaries is not simply the result of widespread up-regulation of cell adhesion molecules on endothelial cells by circulating cytokines. Rather, inflammatory cells may be directed to specific areas of the coronary arteries targeted by a pathogen causing KD. Our results suggest that E-selectin and VCAM-1 expression on neovasculature may contribute to neoangiogenesis and prolonged CAA inflammation and that integrin beta1 might be involved in fibroblastic remodeling of acute KD CAA.

Exercise capacity and incidence of myocardial perfusion defects after Kawasaki disease in children and adolescents

OBJECTIVES

This study evaluated exercise performance and myocardial perfusion during exercise in patients with Kawasaki disease who had a broad spectrum of residual coronary abnormalities.

BACKGROUND

Reports of exercise performance after Kawasaki disease have generally included a small number of patients evaluated by various protocols, frequently with incomplete data. Myocardial perfusion studies have usually been limited to those using pharmacologically induced coronary vasodilation. Therefore, to our knowledge there has not been a large study directly correlating exercise performance, electrocardiographic (ECG) changes and myocardial perfusion imaging.

METHODS

Forty-six patients were classified into three groups on the basis of coronary artery status: group 1 (n = 27) had no objective evidence of coronary artery lesions; group 2 (n = 11) had resolved aneurysms; group 3 (n = 8) had persistent coronary aneurysms. All patients underwent exercise testing with monitoring of ECG changes and oxygen consumption. Single-photon emission computed tomographic imaging was performed at rest and during peak exercise using technetium-99m sestamibi.

RESULTS

Maximal oxygen consumption was within normal limits and was similar for all three groups. Five patients had mild ST segment changes at peak exercise. Two of these patients had stress-induced perfusion defects. Myocardial perfusion defects were present in 37% of patients in group 1, 63% in group 2 and 100% in group 3. Perfusion defects corresponded to the coronary artery lesion site in all but three patients.

CONCLUSIONS

Maximal oxygen consumption is normal after Kawasaki disease regardless of coronary artery status. Stress-induced perfusion defects are frequent even in the absence of coronary abnormalities and are common in the absence of ST segment changes suggestive of ischemia.

Leukotriene B4 and Kawasaki disease

The role of LTB4 in Kawasaki disease as a chemo-attractant and immunomodulator is reviewed through our own experience and reports by other investigators. In our experiment using 19 patients, we measured calcium ionophore-stimulated LTB4 synthesis in PMNs obtained in three different stages of the illness (acute, convalescent and recovered phases). LTB4 synthesis was significantly increased in the convalescent phase of the illness. Other investigators showed increased serum-LTB4 concentration in acute as well as convalescent phases, suggesting that LTB4 participated in the inflammatory process of Kawasaki disease as an inflammatory mediator and immunomodulator. However, no difference was found in LTB4 synthetic activity in PMNs in any phases of the illness between the patients with and without coronary lesions, which indicated that LTB4 was not a parameter of coronary aneurysm formation. Therapeutic use of high-dose gamma-globulin showed a tendency to decreased LTB4 synthesis in PMNs, although it is not conclusive.

Spontaneous coronary artery dissection: case report and evidence for a defect in collagen metabolism

Spontaneous coronary artery dissection is a rare disease with a higher prevalence in women, especially in the post-partum state. In one case, we attempted to relate this pathology to a disorder in collagen metabolism. A 32-year-old woman presented two episodes of myocardial infarction, 2 and 4 months after delivery which were shown to be due to two consecutive coronary artery dissections on coronary angiogram. Collagen metabolism was investigated in skin fibroblast cultures derived from the patient, and in control fibroblast cultures. After protein labelling in culture, total protein and collagen synthesis were determined. Quantification of procollagen synthesized in cell cultures and their rate of conversion into collagen were determined both in the culture media and a cell layer extract by DEAE cellulose chromatography. The results showed a reduced total collagen synthesis in the cultures of the patient in comparison with control cultures. The ratio between type I and III procollagen was not altered. The rate of conversion of procollagen into collagen was higher in the pathological cultures than in control cultures. Impaired collagen synthesis due perhaps to a change in hormonal equilibrium in the post-partum state might therefore have been responsible for coronary artery dissection.