Evidence for selection of 11 amino acid CDR3 domains in V kappa III-derived immunoglobulin light chains in Kawasaki disease

Recent Advances in Kawasaki Disease

Kawasaki disease (KD) is characterized with acute systemic vasculitis, occurs predominantly in children between 6 months to 5 years of age. Patients with this disease recover well and the disease is self-limited in most cases. Since it can lead to devastating cardiovascular complications, KD needs special attention. Recent reports show steady increases in the prevalence of KD in both Japan and Korea. However, specific pathogens have yet to be found. Recent advances in research on KD include searches for genetic susceptibility related to KD and research on immunopathogenesis based on innate and acquired immunity. Also, search for etiopathogenesis and treatment of KD has been actively sought after using animal models. In this paper, the recent progress of research on KD was discussed.

Circulating interleukin 17 is increased in the acute stage of Kawasaki disease

OBJECTIVES

During the acute phase, patients with Kawasaki disease (KD), an acute systemic vasculitis, demonstrate a drastic increase in serum interleukin-6 (IL-6), which parallels the duration of the fever. Recently, IL-17 has been reported to induce IL-6 production. The aim of this study was to elucidate the involvement of IL-17 in the pathogenesis of KD.

METHODS

Serum samples were obtained from patients with KD (n=30) and normal controls (n=20), and the concentrations of IL-17 and IL-6 measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with the normal controls (2.08 +/- 2.14 pg/mL), serum IL-17 was markedly elevated in patients with acute KD (25.47 +/- 5.05 pg/mL): levels gradually decreased in the subacute phase (5.94 +/- 2.83 pg/mL). In the acute phase, levels of IL-6 were 83.52 +/- 19.12 pg/L, which correlated well with the serum levels of IL-17.

CONCLUSION

These results suggest that IL-17 may be involved in the development of, or the effects of inflammation in KD.

Kawasaki disease

Kawasaki disease is an acute febrile, systemic vasculitic syndrome of an unknown etiology that primarily occurs in children younger than five years of age. The principal presentations of Kawasaki disease include fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develops in 15% to 25% of untreated children with the disease, which may later lead to myocardial infarction, sudden death, or ischemic heart disease. Treatment with intravenous gamma globulin (IVIG) is effective, but the mode of action is still unclear. The development of a diagnostic test, a more specific therapy, and ultimately the prevention of this potentially fatal illness in children are all dependent upon the continued advances in determining the etiopathogenesis of this fascinating disorder.

Cloning the arterial IgA antibody response during acute Kawasaki disease

Kawasaki disease (KD) is the most common acquired cardiac disease in children in developed nations. The etiology of KD is unknown but likely to be a ubiquitous microbial agent. Previously, we showed that oligoclonal IgA plasma cells infiltrate coronary arteries and other inflamed tissues in acute KD. We demonstrated that a synthetic Ab made using an alpha H chain sequence prevalent in acute KD arterial tissue detected Ag in acute KD coronary arteries, lung, and other inflamed tissues and that Ag localized to cytoplasmic inclusion bodies in the acute KD ciliated bronchial epithelium. In this study, we synthesized a panel of mAbs from alpha and kappa chain sequences present in the KD arterial wall and tested the Abs for binding to acute KD tissues. We report that all of the synthetic mAbs that bind to acute KD tissues detect Ag in cytoplasmic inclusion bodies in the acute KD ciliated bronchial epithelium. Abs made from alpha sequences that were prevalent in KD arterial tissue show stronger binding to acute KD tissues than Abs made from less prevalent sequences. These findings highlight the likely importance of the inclusion bodies in the etiopathogenesis of acute KD, confirm that the IgA Ab response in acute KD is Ag driven, and demonstrate the usefulness of cloning the Ab response in diseased tissues to identify disease-relevant Ags.

Interleukin 6 gene promoter polymorphism is not associated with Kawasaki disease

We examined the IL-6 gene promoter and detected several interesting promoter polymorphisms: GGGCTG insertion at +162 bp and G deletion at +168 bp positions (M1), A to G substitution at -594 bp (M2) of the reported IL-6 promoter sequence. Other rare variations were also observed at several positions: -583 bp (T insertion), -507 bp (C insertion), -71 bp (T deletion), +17 bp (C insertion), and +121 bp (GC insertion). Although Kawasaki disease (KD) patients demonstrate a drastic increase in serum interleukin-6 (IL-6) during the acute phase that parallels the duration of fever, there were no significant differences in the nucleotide sequence between the KD patients and normal control group. By transient transfection with IL-6 gene promoter-luciferase fusion plasmids into CV-1 cells, we tested the functional significances of the polymorphisms. Mutations at +162 bp, +168 bp and -594 bp significantly decreased luciferase expression (P < 0.05), suggesting the promoter elements flanking the mutated nucleotides are important in transcriptional activation.