Search

Background Kawasaki disease (KD) is a febrile illness of young childhood that can result in coronary artery aneurysms and death. Coronavirus disease 2019 (COVID-19) mitigation strategies resulted in a marked decrease in KD cases worldwide, supporting a transmissible respiratory agent as the cause. We previously reported a peptide epitope recognized by monoclonal antibodies (MAbs) derived from clonally expanded peripheral blood plasmablasts from 3 of 11 KD children, suggesting a common disease trigger in a subset of patients with KD. Methods We performed amino acid substitution scans to develop modified peptides with improved recognition by KD MAbs. We prepared additional MAbs from KD peripheral blood plasmablasts and assessed MAb characteristics that were associated with binding to the modified peptides. Results We report a modified peptide epitope that is recognized by 20 MAbs from 11 of 12 KD patients. These MAbs predominantly use heavy chain VH3-74 ; two-thirds of VH3-74 plasmablasts from these patients recognize the epitope. The MAbs were nonidentical between patients but share a common complementarity-determining region 3 (CDR3) motif. Conclusions These results demonstrate a convergent VH3-74 plasmablast response to a specific protein antigen in children with KD, supporting one predominant causative agent in the etiopathogenesis of the illness. [ABSTRACT FROM AUTHOR]

Background Kawasaki disease (KD) is the leading cause of childhood acquired heart disease in developed nations and can result in coronary artery aneurysms and death. Clinical and epidemiologic features implicate an infectious cause but specific antigenic targets of the disease are unknown. Peripheral blood plasmablasts are normally highly clonally diverse but the antibodies they encode are approximately 70% antigen-specific 1–2 weeks after infection. Methods We isolated single peripheral blood plasmablasts from children with KD 1–3 weeks after onset and prepared 60 monoclonal antibodies (mAbs). We used the mAbs to identify their target antigens and assessed serologic response among KD patients and controls to specific antigen. Results Thirty-two mAbs from 9 of 11 patients recognize antigen within intracytoplasmic inclusion bodies in ciliated bronchial epithelial cells of fatal cases. Five of these mAbs, from 3 patients with coronary aneurysms, recognize a specific peptide, which blocks binding to inclusion bodies. Sera from 5/8 KD patients day ≥ 8 after illness onset, compared with 0/17 infant controls (P  < .01), recognized the KD peptide antigen. Conclusions These results identify a protein epitope targeted by the antibody response to KD and provide a means to elucidate the pathogenesis of this important worldwide pediatric problem. [ABSTRACT FROM AUTHOR]

Background. Kawasaki disease (KD) is widely viewed as an acute arteritis. However, our pathologic studies show that chronic coronary arteritis can persist long after disease onset and is closely linked with arterial stenosis. Transcriptome profiling of acute KD arteritis tissues revealed upregulation of T lymphocyte, type I interferon, and allograft inflammatory factor-1 (AIF1) genes. We determined whether these immune responses persist in chronic KD arteritis, and we investigated the role of AIF1 in these responses. Methods. Gene expression in chronic KD and childhood control arteries was determined by real-time reverse-transcriptase polymerase chain reaction, and arterial protein expression was determined by immunohistochemistry and immunofluorescence. Allograft inflammatory factor-1 small-interfering ribonucleic acid macrophage treatment was performed to investigate the role of AIF1 in macrophage and T lymphocyte activation. Results. Allograft inflammatory factor-1 protein was highly expressed in stenotic KD arteries and colocalized with the macrophage marker CD68. T lymphocyte and interferon pathway genes were significantly upregulated in chronic KD coronary artery tissues. Alpha interferon-induced macrophage expression of CD80 and major histocompatibility complex class II was dependent on AIF1, and macrophage expression of AIF1 was required for antigen-specific T lymphocyte activation. Conclusions. Allograft inflammatory factor-1, originally identified in posttransplant arterial stenosis, is markedly upregulated in KD stenotic arterial tissues. T lymphocyte and type I interferon responses persist in chronic KD arteritis. Allograft inflammatory factor-1 may play multiple roles linking type I interferon response, macrophage activation, and antigen-specific T lymphocyte activation. These results suggest the likely importance of lymphocyte-myeloid cell cross-talk in the pathogenesis of KD arteritis and can inform selection of new immunotherapies for clinical trials in high-risk KD children. [ABSTRACT FROM AUTHOR]

Reporting progress against targets for international biodiversity agreements is hindered by a shortage of suitable biodiversity data. We describe a cost-effective system involving Reef Life Survey citizen scientists in the systematic collection of quantitative data covering multiple phyla that can underpin numerous marine biodiversity indicators at high spatial and temporal resolution. We then summarize the findings of a continentaland decadal-scale State of the Environment assessment for rocky and coral reefs based on indicators of ecosystem state relating to fishing, ocean warming, and invasive species and describing the distribution of threatened species. Fishing impacts are widespread, whereas substantial warming-related change affected some regions between 2005 and 2015. Invasive species are concentrated near harbors in southeastern Australia, and the threatened-species index is highest for the Great Australian Bight and Tasman Sea. Our approach can be applied globally to improve reporting against biodiversity targets and enhance public and policymakers' understanding of marine biodiversity trends. [ABSTRACT FROM AUTHOR]

The majority of the world's forests are used for multiple purposes, which often include the potentially conflicting goals of timber production and biodiversity conservation. A scientifically validated management approach that can reduce such conflicts is retention forestry, an approach modeled on natural processes, which emerged in the last 25 years as an alternative to clearcutting. A portion of the original stand is left unlogged to maintain the continuity of structural and compositional diversity. We detail retention forestry's ecological role, review its current practices, and summarize the large research base on the subject. Retention forestry is applicable to all forest Homes, complements conservation in reserves, and represents bottom-up conservation through forest manager involvement. A research challenge is to identify thresholds for retention amounts to achieve desired outcomes. We define key issues for future development and link retention forestry with land-zoning allocation at various scales, expanding its uses to forest restoration and the management of uneven-age forests. [ABSTRACT FROM AUTHOR]

Background. Intracytoplasmic inclusion bodies (ICI) have been identified in ciliated bronchial epithelium of Kawasaki disease (KD) patients using a synthetic antibody derived from acute KD arterial IgA plasma cells; ICI may derive from the KD etiologic agent.Methods. Acute KD bronchial epithelium was subjected to immunofluorescence for ICI and cytokeratin, high-throughput sequencing, and transmission electron microscopy (TEM). Interferon pathway gene expression profiling was performed on KD lung.Results. An intermediate filament cytokeratin “cage” was not observed around KD ICI, making it unlikely that ICI are overproduced or misfolded human protein aggregates. Many interferon-stimulated genes were detected in the bronchial epithelium, and significant modulation of the interferon response pathway was observed in the lung tissue of KD patients. No known virus was identified by sequencing. Aggregates of virus-like particles (VLP) were detected by TEM in all 3 acute KD patients from whom nonembedded formalin-fixed lung tissue was available.Conclusions. KD ICI are most likely virus induced; bronchial cells with ICI contain VLP that share morphologic features among several different RNA viral families. Expedited autopsies and tissue fixation from acute KD fatalities are urgently needed to more clearly ascertain the VLP. These findings are compatible with the hypothesis that the infectious etiologic agent of KD may be a “new” RNA virus. [ABSTRACT FROM PUBLISHER]

Background. In developed nations, Kawasaki disease (KD) is the most common cause of acquired heart disease in children. An infectious etiology is likely but has not yet been identified. We have previously reported that oligoclonal immunoglobulin A plasma cells infiltrate acute KD tissues and that synthetic KD antibodies detect a distinctive spheroidal antigen in acute KD ciliated bronchial epithelium. Methods. To further characterize the antigen in acute KD bronchi, we examined paraffin-embedded ciliated bronchial epithelium using light microscopy (LM) and transmission electron microscopy (TEM). Results. The spheroids observed by immunohistochemistry (IHC) are visualized as inclusion bodies with hematoxylin-eosin and nucleic acid stains and in methylene blue/azure IT/basic fuchsin trichrome-stained plastic sections, suggesting the presence of both protein and nucleic acid. The structures visualized by LM correspond to homogeneous electron-dense perinuclear inclusion bodies (up to 1.4 microns in diameter) in ciliated bronchial epithelium from 4 patients with acute KD examined by TEM. Inclusion bodies were not present in control bronchial epithelium or in nonciliated cells. Conclusions. The antigen detected in acute KD ciliated bronchial epithelium by IHC with synthetic KD antibodies resides in cytoplasmic inclusion bodies that are consistent with aggregates of viral proteins and associated nucleic acid and may derive from the etiologic agent of KD. [ABSTRACT FROM AUTHOR]

Kawasaki disease (KD) is a self-limited, systemic vasculitis of children for which an infectious trigger is suspected. Recently, an association between KD and human coronavirus (HCoV)-New Haven (NH) was reported, on the basis of polymerase chain reaction (PCR) with primers that also amplified HCoV-NL63. We investigated the possible association between these HCoVs in the respiratory tract and KD by reverse-transcriptase (RT) PCR and viral culture in a geographically and ethnically diverse population. Only 1 (2%) of 48 patients with acute KD was positive by RT-PCR for HCoV-NL63/NH in a nasopharyngeal swab. These data do not support an association between these HCoVs and KD. [ABSTRACT FROM AUTHOR]

Research on media effects has documented the media's influence on beliefs and behavior while cross-cultural psychology has documented the effects of the language used in communication on identification with the ingroup and the outgroup. Media usage in the outgroup language should, therefore, affect identification patterns. This research investigates media effects in the acculturation process through a longitudinal design involving minority and majority group members evolving in the same bilingual environment. Subjects were Francophone students (N = 235) from minority and majority settings attending a bilingual (French-English) university. Results revealed that majority students increased significantly written and public media consumption in English whereas minority students increased French written media consumption. Furthermore, increased usage of English written and audiovisual media was related to identity changes in favour of the Anglophone group. Finally, path analysis emphasized the mediating role played by English language confidence and the determining role of ethnolinguistic vitality. [ABSTRACT FROM AUTHOR]

Background: Kawasaki disease (KD) is the most common acquired cardiac disease in children in developed nations. The etiology is unknown, but a ubiquitous infectious agent appears to be likely. Immunoglobulin A plasma cells infiltrate inflamed tissues in acute KD, producing oligoclonal, antigen-driven antibodies.Methods: To identify antigens important in the pathogenesis of KD, oligoclonal KD antibodies were prepared in vitro and tested by immunohistochemistry experiments on tissues from patients with acute KD and from control subjects and were also tested for reactivity with human inflammatory proteins.Results: By use of synthetic antibody A, specific binding to a cytoplasmic antigen in proximal bronchial epithelium was observed in 10 of 13 patients with acute KD but in 0 of 9 control subjects (P=.001). A subset of macrophages was positive in at least 1 inflamed tissue from all 17 patients with acute KD. Antigen was detected in 9 of 12 acute KD coronary artery aneurysms but in 0 of 10 control coronary arteries (P<.001). The antigen is not immunoglobulin or any of 40 common inflammatory proteins.Conclusions: We report the first demonstration of a KD-associated antigen in the tissues targeted by the disease. Our findings are consistent with the theory that KD is caused by a previously unidentified respiratory infectious agent with tropism for vascular tissue. [ABSTRACT FROM AUTHOR]

Reports on immunoglobulin G (IgG) plasma cell (PC) infiltration of proximal respiratory tract, pancreas, kidney and coronary artery in acute Kawasaki disease (KD). Significant increase in IgG PC in the trachea of patients who died from the disease and in children with fatal respiratory viral infection; Evidence on the entry of the KD etiologic agent through the upper respiratory tract resulting in an IgG immune response.