Abstract O.24: Gut Microflora Influences Pathology in the Kawasaki Disease Vasculitis Mouse Model

Background: Kawasaki Disease (KD) is the leading cause of acquired heart disease in the US. We have demonstrated the critical role of innate immune responses via IL-1R/MyD88 signaling in the Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model. The diversity and composition of microflora (both bacterial and fungal) have been associated with the regulation and alterations of immune responses and various pathologies. However, the role of gut microbiota in immunopathology of KD has not been investigated. Objective: To evaluate the role of gut microflora in development of coronary arteritis, and vascular abnormalities in KD mouse model. Methods and Results: We investigated the role of gut microflora in the LCWE-induced KD mouse model, using Specific-Pathogen Free (SPF) and Germ Free (GF) mice (C57BL/6). GF mice showed a significant decrease of KD lesions, including coronary arteritis compared with SPF mice. The development of LCWE-induced AAA, which we recently discovered in this mouse model, was also markedly diminished in GF mice. In addition to GF mice, we also investigated the specific role of commensal fungi, and determined whether altered fungal burden in this KD mouse model contributes to disease severity. To deplete fungi in the gut microflora, we exposed pregnant SPF mice and their offspring to fluconazole (antifungal) in their drinking water for 5 wks and induced KD. The fluconazole treated mice had significantly reduced coronary arteritis, and AAA compared to controls. Since Dectin-1 has emerged as a key receptor that recognizes β-1,3-glucans found in the cell wall of nearly all fungi, we next induced KD in Dectin-1 deficient mice. Dectin-1 deficient mice also had significantly reduced KD lesions such as coronary arteritis compared with WT mice. Conclusions: We demonstrate here that gut microflora play a critical role in the development of KD vasculitis in LCWE-induced mouse model. Our results suggest that fungi in the intestinal microbiota may specifically control the induction and severity of KD vasculitis, which may be mediated by Dectin-1. These findings provide a new perspective on the potential role of the microbiome in KD pathogenesis and may offer new diagnostic and therapeutic strategies for KD patients.

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Abstract 636: Gut Microflora Influences Pathology in the Kawasaki Disease (KD) Vasculitis Mouse Model

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.35.suppl_1.636 ◽

2015 ◽

Vol 35 (suppl_1) ◽

Author(s):

Daiko Wakita ◽

Yosuke Kurashima ◽

Yoshihiro Takasato ◽

Youngho Lee ◽

Kenichi Shimada ◽

...

Keyword(s):

Mouse Model ◽

Immune Responses ◽

Critical Role ◽

Gut Microflora ◽

Vascular Abnormalities ◽

Coronary Arteritis ◽

Specific Pathogen ◽

New Perspective ◽

Bacteria And Fungi

Background: KD is the leading cause of acquired heart disease in the US. We have demonstrated the critical role of innate immune responses via IL-1R/MyD88 signaling in the Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model. The diversity and composition of microflora (both bacterial and fungal) have been associated with the regulation and alterations of immune responses and various pathologies. However, the role of gut microbiota in immunopathology of KD has not been investigated. Objective: To evaluate the role of gut microflora in development of coronary arteritis, and vascular abnormalities in KD mouse model. Methods and Results: We investigated the role of gut microflora in the LCWE-induced KD mouse model, using Specific-Pathogen Free (SPF) and Germ Free (GF) mice (C57BL/6). GF mice showed a significant decrease of KD lesions, including coronary arteritis compared with SPF mice. The development of LCWE-induced AAA, which we recently discovered in this mouse model, was also markedly diminished in GF mice. In addition to GF mice, we also investigated the specific role of commensal bacteria and/or fungi, and determined whether altered microorganism burden in this KD mouse model contributes to disease severity. To deplete bacteria and/or fungi in the gut microflora, we exposed pregnant SPF mice and their offspring to antibiotics cocktail (Abx) or antifungal drug (fluconazole; Fluc) in their drinking water for 5 wks and induced KD. The mice treated with Abx or Fluc had significantly reduced coronary arteritis and AAA compared to controls. The Abx plus Fluc administration showed marked decrease of KD vasculitis. Conclusions: We demonstrate here that gut microflora play a critical role in the development of KD vasculitis in LCWE-induced mouse model. Our results suggest that both bacteria and fungi in the intestinal microbiota may control the induction and severity of KD vasculitis. These findings provide a new perspective on the potential role of the microbiome in KD pathogenesis and may offer new diagnostic and therapeutic strategies for KD patients.

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Abstract 426: Abdominal Aorta Dilatation and Aneurysm in Kawasaki Disease Vasculitis Mouse Model: Role of IL-1 Signaling

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.35.suppl_1.426 ◽

2015 ◽

Vol 35 (suppl_1) ◽

Author(s):

Daiko Wakita ◽

Yosuke Kurashima ◽

Youngho Lee ◽

Kenichi Shimada ◽

Shuang Chen ◽

...

Keyword(s):

Kawasaki Disease ◽

Mouse Model ◽

Abdominal Aorta ◽

Active Form ◽

Aortic Dilatation ◽

Caspase 1 ◽

Abdominal Aortic ◽

Aorta Dilatation ◽

Deficient Mice

Background: Kawasaki disease (KD) is the most common cause of acquired cardiac disease among US children. KD causes coronary artery aneurysms in up to 25% of untreated patients, and less frequently aneurysms in other systemic arteries including the abdominal aorta. Objective: To evaluate the development of abdominal aorta dilatation and aneurysm in KD mouse model and investigate the role of IL-1 signaling. Methods and Results: We investigated the incidence and progression of abdominal aorta aneurysm (AAA) and dilatation in the Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model at 1, 2, 5 wks. Over 80% of the mice developed significant dilation of abdominal aorta at 1 wk with progressively greater dilatation at 5 wks, with greater severity in males. KD mice showed fusiform and saccular AAA, which were always below the renal artery. Immunohistochemistry showed significant intimal proliferation, massive myofibroblastic proliferation that breaks the elastin layer, infiltration of large numbers of neutrophils and macrophages into the media and adventitia. IL-1R- or IL-1beta-deficient mice were completely protected from the KD associated abdominal aorta dilatation and AAA. Active form Caspase-1 was detected at infiltrated macrophages and the Caspase-1-deficient mice showed significant reduction of AAA formation. Blockade of IL-1/IL-1R signaling with IL-1R antagonist (Anakinra), or neutralizing antibody against IL-1α or IL-1β significantly prevented the AAA in the KD mice. Conclusions: We report a new model of AAA and aortic dilatation in the LCWE-induced KD mouse model. These studies suggest that in children with KD the incidence of abdominal aortic dilatation and AAA maybe higher than currently appreciated, thus requiring prospective studies to determine the frequency of these vascular complications. Our findings also demonstrate that IL-1 plays an important role in development of LCWE-induced abdominal aortic lesions and blockade of IL-1 signaling may be a promising therapeutic target not only for KD vasculitis and coronary arteritis, but also for abdominal aorta dilatation and AAA associated with the disease.

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Abstract 71: Abdominal Aorta Dilatation and Aneurysm in Kawasaki Disease Vasculitis Mouse Model: Role of IL-1 Signaling

Circulation ◽

10.1161/circ.131.suppl_2.71 ◽

2015 ◽

Vol 131 (suppl_2) ◽

Author(s):

Daiko Wakita ◽

Youngho Lee ◽

Kenichi Shimada ◽

Shuang Chen ◽

Timothy R Crother ◽

...

Keyword(s):

Coronary Artery ◽

Kawasaki Disease ◽

Mouse Model ◽

Abdominal Aorta ◽

Vascular Complications ◽

Aortic Dilatation ◽

Coronary Arteritis ◽

Abdominal Aortic ◽

Aorta Dilatation

Background: Kawasaki disease (KD) is the most common cause of acute systemic vasculitis and acquired cardiac disease among US children. KD causes coronary artery aneurysms in up to 25% of untreated patients, and less frequently aneurysms in other systemic arteries including the abdominal aorta. Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model mimics histopathologically the coronary artery lesions seen in KD patients. Objective: To evaluate the development of abdominal aorta dilatation and aneurysm in KD mouse model and investigate the role of IL-1 signaling. Methods and Results: We investigated the incidence and progression of abdominal aorta aneurysm (AAA) and dilatation in the KD model at 1, 2, 5 weeks. Over 80% of the mice developed significant dilation of abdominal aorta at 2 wks with progressively greater dilatation at 5 wks, with greater severity in males. KD mice showed fusiform and saccular AAA, which were always below the renal artery. Immunohistochemistry showed significant intimal proliferation, massive myofibroblastic proliferation that breaks the elastin layer, infiltration of large numbers of neutrophils and macrophages into the media and adventitia. IL-1R- or IL-1beta-deficient mice were completely protected from the KD associated abdominal aorta dilatation and AAA. IL-1R antagonist (Anakinra) significantly prevented the abdominal aorta dilatation and AAA (in addition to blocking coronary arteritis) in the KD mice. Conclusions: We report a new model of AAA and aortic dilatation in the LCWE-induced KD mouse model. These studies suggest that in children with KD the incidence of abdominal aortic dilatation and AAA maybe higher than currently appreciated, thus requiring prospective studies to determine the frequency of these vascular complications. Our findings also demonstrate that IL-1 plays an important role in development of LCWE-induced abdominal aortic lesions and blockade of IL-1 signaling may be a promising therapeutic target not only for KD vasculitis and coronary arteritis, but also for abdominal aorta dilatation and AAA associated with the disease.

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Faculty Opinions recommendation of Critical role of the IgM Fc receptor in IgM homeostasis, B-cell survival, and humoral immune responses.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717959020.793462522 ◽

2012 ◽

Author(s):

Takeshi Tsubata

Keyword(s):

Immune Responses ◽

B Cell ◽

Cell Survival ◽

Critical Role ◽

Fc Receptor ◽

Humoral Immune ◽

Humoral Immune Responses ◽

B Cell Survival

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GSDMD contributes to host defence against Staphylococcus aureus skin infection by suppressing the Cxcl1–Cxcr2 axis

Veterinary Research ◽

10.1186/s13567-021-00937-7 ◽

2021 ◽

Vol 52 (1) ◽

Author(s):

Zhen-Zhen Liu ◽

Yong-Jun Yang ◽

Feng-Hua Zhou ◽

Ke Ma ◽

Xiao-Qi Lin ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Skin Infection ◽

Bacterial Colonization ◽

Critical Role ◽

Host Defence ◽

Skin Damage ◽

Microbial Infection ◽

Caspase 1 ◽

Deficient Mice

AbstractGasdermin D (GSDMD), a member of the gasdermin protein family, is a caspase substrate, and its cleavage is required for pyroptosis and IL-1β secretion. To date, the role and regulatory mechanism of GSDMD during cutaneous microbial infection remain unclear. Here, we showed that GSDMD protected against Staphylococcus aureus skin infection by suppressing Cxcl1–Cxcr2 signalling. GSDMD deficiency resulted in larger abscesses, more bacterial colonization, exacerbated skin damage, and increased inflammatory cell infiltration. Although GSDMD deficiency resulted in defective IL-1β production, the critical role of IL-1β was counteracted by the fact that Caspase-1/11 deficiency also resulted in less IL-1β production but did not aggravate disease severity during S. aureus skin infection. Interestingly, GSDMD-deficient mice had increased Cxcl1 secretion accompanied by increased recruitment of neutrophils, whereas Caspase-1/11-deficient mice presented similar levels of Cxcl1 and neutrophils as wild-type mice. Moreover, the absence of GSDMD promoted Cxcl1 secretion in bone marrow-derived macrophages induced by live, dead, or different strains of S. aureus. Corresponding to higher transcription and secretion of Cxcl1, enhanced NF-κB activation was shown in vitro and in vivo in the absence of GSDMD. Importantly, inhibiting the Cxcl1–Cxcr2 axis with a Cxcr2 inhibitor or anti-Cxcl1 blocking antibody rescued host defence defects in the GSDMD-deficient mice. Hence, these results revealed an important role of GSDMD in suppressing the Cxcl1–Cxcr2 axis to facilitate pathogen control and prevent tissue damage during cutaneous S. aureus infection.

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Essential role of IPS-1 in innate immune responses against RNA viruses

Journal of Experimental Medicine ◽

10.1084/jem.20060792 ◽

2006 ◽

Vol 203 (7) ◽

pp. 1795-1803 ◽

Cited By ~ 345

Author(s):

Himanshu Kumar ◽

Taro Kawai ◽

Hiroki Kato ◽

Shintaro Sato ◽

Ken Takahashi ◽

...

Keyword(s):

Rna Viruses ◽

Rna Virus ◽

Critical Role ◽

Nuclear Factor Κb ◽

Type I ◽

Innate Immune Responses ◽

Antiviral Responses ◽

Deficient Mice

IFN-β promoter stimulator (IPS)-1 was recently identified as an adapter for retinoic acid–inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (Mda5), which recognize distinct RNA viruses. Here we show the critical role of IPS-1 in antiviral responses in vivo. IPS-1–deficient mice showed severe defects in both RIG-I– and Mda5-mediated induction of type I interferon and inflammatory cytokines and were susceptible to RNA virus infection. RNA virus–induced interferon regulatory factor-3 and nuclear factor κB activation was also impaired in IPS-1–deficient cells. IPS-1, however, was not essential for the responses to either DNA virus or double-stranded B-DNA. Thus, IPS-1 is the sole adapter in both RIG-I and Mda5 signaling that mediates effective responses against a variety of RNA viruses.

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Immunogenicity and protective efficacy of enterotoxigenic Escherichia coli (ETEC) total RNA against ETEC challenge in a mouse model

Scientific Reports ◽

10.1038/s41598-020-77551-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mandi Liu ◽

Yue Zhang ◽

Di Zhang ◽

Yun Bai ◽

Guomei Liu ◽

...

Keyword(s):

Escherichia Coli ◽

Mouse Model ◽

Immune Responses ◽

Protective Efficacy ◽

Enterotoxigenic Escherichia Coli ◽

Economic Losses ◽

Th2 Response ◽

Total Rna ◽

Etec Infection

AbstractEnterotoxigenic Escherichia coli (ETEC), an essential cause of post-weaning diarrhea (PWD) in piglets, leads to significant economic losses to the pig industry. The present study aims to identify the role of ETEC total RNA in eliciting immune responses to protect animals against ETEC infection. The results showed that the total RNA isolated from pig-derived ETEC K88ac strain effectively stimulated the IL-1β secretion of porcine intestinal epithelial cells (IPEC-J2). The mouse model immunized with ETEC total RNA via intramuscular injection (IM) or oral route (OR) was used to evaluate the protective efficiency of the ETEC total RNA. The results suggested that 70 μg ETEC total RNA administered by either route significantly promoted the production of the serum IL-1β and K88ac specific immunoglobulins (IgG, IgM, and IgA). Besides, the ETEC RNA administration augmented strong mucosal immunity by elevating K88ac specific IgA level in the intestinal fluid. Intramuscularly administered RNA induced a Th1/Th2 shift toward a Th2 response, while the orally administered RNA did not. The ETEC total RNA efficiently protected the animals against the ETEC challenge either by itself or as an adjuvant. The histology characterization of the small intestines also suggested the ETEC RNA administration protected the small intestinal structure against the ETEC infection. Particularly of note was that the immunity level and protective efficacy caused by ETEC RNA were dose-dependent. These findings will help understand the role of bacterial RNA in eliciting immune responses, and benefit the development of RNA-based vaccines or adjuvants.

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Brain-Specific SNAP-25 Deletion Leads to Elevated Extracellular Glutamate Level and Schizophrenia-Like Behavior in Mice

Neural Plasticity ◽

10.1155/2017/4526417 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 12

Author(s):

Hua Yang ◽

Mengjie Zhang ◽

Jiahao Shi ◽

Yunhe Zhou ◽

Zhipeng Wan ◽

...

Keyword(s):

Cerebral Cortex ◽

Mouse Model ◽

Glutamate Release ◽

Critical Role ◽

Conditional Knockout ◽

Snare Complex ◽

Extracellular Glutamate ◽

Glutamate Level

Several studies have associated reduced expression of synaptosomal-associated protein of 25 kDa (SNAP-25) with schizophrenia, yet little is known about its role in the illness. In this paper, a forebrain glutamatergic neuron-specific SNAP-25 knockout mouse model was constructed and studied to explore the possible pathogenetic role of SNAP-25 in schizophrenia. We showed that SNAP-25 conditional knockout (cKO) mice exhibited typical schizophrenia-like phenotype. A significantly elevated extracellular glutamate level was detected in the cerebral cortex of the mouse model. Compared with Ctrls, SNAP-25 was dramatically reduced by about 60% both in cytoplasm and in membrane fractions of cerebral cortex of cKOs, while the other two core members of SNARE complex: Syntaxin-1 (increased ~80%) and Vamp2 (increased ~96%) were significantly increased in cell membrane part. Riluzole, a glutamate release inhibitor, significantly attenuated the locomotor hyperactivity deficits in cKO mice. Our findings provide in vivo functional evidence showing a critical role of SNAP-25 dysfunction on synaptic transmission, which contributes to the developmental of schizophrenia. It is suggested that a SNAP-25 cKO mouse, a valuable model for schizophrenia, could address questions regarding presynaptic alterations that contribute to the etiopathophysiology of SZ and help to consummate the pre- and postsynaptic glutamatergic pathogenesis of the illness.

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