Showing papers by "Masahiro Yamamoto published in 2015"
TL;DR: Guanylate-binding proteins GBP2 and GBP5 are identified as key activators of AIM2 during infection with F. novicida and facilitated the presentation of ligands by directly attacking cytosolic bacteria in addition to their role in host defense against vacuolar pathogens.
Abstract: The AIM2 inflammasome detects double-stranded DNA in the cytosol and induces caspase-1-dependent pyroptosis as well as release of the inflammatory cytokines interleukin 1β (IL-1β) and IL-18. AIM2 is critical for host defense against DNA viruses and bacteria that replicate in the cytosol, such as Francisella tularensis subspecies novicida (F. novicida). The activation of AIM2 by F. novicida requires bacteriolysis, yet whether this process is accidental or is a host-driven immunological mechanism has remained unclear. By screening nearly 500 interferon-stimulated genes (ISGs) through the use of small interfering RNA (siRNA), we identified guanylate-binding proteins GBP2 and GBP5 as key activators of AIM2 during infection with F. novicida. We confirmed their prominent role in vitro and in a mouse model of tularemia. Mechanistically, these two GBPs targeted cytosolic F. novicida and promoted bacteriolysis. Thus, in addition to their role in host defense against vacuolar pathogens, GBPs also facilitate the presentation of ligands by directly attacking cytosolic bacteria.
279 citations
TL;DR: This work has found that the transcription factor IRF1 was required for activation of the AIM2 inflammasome during infection with the Francisella tularensis subspecies novicida, whereas engagement of the CVs by mouse cytomegalovirus (MCMV) or transfected double-stranded DNA did not require IRF 1.
Abstract: Inflammasomes are critical for mounting host defense against pathogens. The molecular mechanisms that control activation of the AIM2 inflammasome in response to different cytosolic pathogens remain unclear. Here we found that the transcription factor IRF1 was required for activation of the AIM2 inflammasome during infection with the Francisella tularensis subspecies novicida (F. novicida), whereas engagement of the AIM2 inflammasome by mouse cytomegalovirus (MCMV) or transfected double-stranded DNA did not require IRF1. Infection of F. novicida detected by the DNA sensor cGAS and its adaptor STING induced type I interferon-dependent expression of IRF1, which drove the expression of guanylate-binding proteins (GBPs); this led to intracellular killing of bacteria and DNA release. Our results reveal a specific requirement for IRF1 and GBPs in the liberation of DNA for sensing by AIM2 depending on the pathogen encountered by the cell.
262 citations
TL;DR: GBPs control the kinetics of inflammasome activation and thereby shape macrophage responses to Chlamydia infections, and reveal that GBPs support fast-kinetics processing and secretion of interleukin-1β and IL-18 by the NLRP3 inflammaome but are dispensable for the secretion of the same cytokines at later times postinfection.
Abstract: Interferon (IFN)-inducible guanylate binding proteins (GBPs) mediate cell-autonomous host resistance to bacterial pathogens and promote inflammasome activation. The prevailing model postulates that these two GBP-controlled activities are directly linked through GBP-dependent vacuolar lysis. It was proposed that the rupture of pathogen-containing vacuoles (PVs) by GBPs destroyed the microbial refuge and simultaneously contaminated the host cell cytosol with microbial activators of inflammasomes. Here, we demonstrate that GBP-mediated host resistance and GBP-mediated inflammatory responses can be uncoupled. We show that PVs formed by the rodent pathogen Chlamydia muridarum, so-called inclusions, remain free of GBPs and that C. muridarum is impervious to GBP-mediated restrictions on bacterial growth. Although GBPs neither bind to C. muridarum inclusions nor restrict C. muridarum growth, we find that GBPs promote inflammasome activation in C. muridarum-infected macrophages. We demonstrate that C. muridarum infections induce GBP-dependent pyroptosis through both caspase-11-dependent noncanonical and caspase-1-dependent canonical inflammasomes. Among canonical inflammasomes, we find that C. muridarum and the human pathogen Chlamydia trachomatis activate not only NLRP3 but also AIM2. Our data show that GBPs support fast-kinetics processing and secretion of interleukin-1β (IL-1β) and IL-18 by the NLRP3 inflammasome but are dispensable for the secretion of the same cytokines at later times postinfection. Because IFN-γ fails to induce IL-1β transcription, GBP-dependent fast-kinetics inflammasome activation can drive the preferential processing of constitutively expressed IL-18 in IFN-γ-primed macrophages in the absence of prior Toll-like receptor stimulation. Together, our results reveal that GBPs control the kinetics of inflammasome activation and thereby shape macrophage responses to Chlamydia infections.
118 citations
TL;DR: It is shown that deletion of ASP5 causes a significant loss in parasite fitness in vitro and an altered virulence in vivo, and it is revealed that ASP5 is necessary for the cleavage of GRA16, GRA19 and GRA20 at the PEXEL-like motif.
Abstract: Toxoplasma gondii possesses sets of dense granule proteins (GRAs) that either assemble at, or cross the parasitophorous vacuole membrane (PVM) and exhibit motifs resembling the HT/PEXEL previously identified in a repertoire of exported Plasmodium proteins. Within Plasmodium spp., cleavage of the HT/PEXEL motif by the endoplasmic reticulum-resident protease Plasmepsin V precedes trafficking to and export across the PVM of proteins involved in pathogenicity and host cell remodelling. Here, we have functionally characterized the T. gondii aspartyl protease 5 (ASP5), a Golgi-resident protease that is phylogenetically related to Plasmepsin V. We show that deletion of ASP5 causes a significant loss in parasite fitness in vitro and an altered virulence in vivo. Furthermore, we reveal that ASP5 is necessary for the cleavage of GRA16, GRA19 and GRA20 at the PEXEL-like motif. In the absence of ASP5, the intravacuolar nanotubular network disappears and several GRAs fail to localize to the PVM, while GRA16 and GRA24, both known to be targeted to the host cell nucleus, are retained within the vacuolar space. Additionally, hypermigration of dendritic cells and bradyzoite cyst wall formation are impaired, critically impacting on parasite dissemination and persistence. Overall, the absence of ASP5 dramatically compromises the parasite's ability to modulate host signalling pathways and immune responses.
103 citations
TL;DR: Clinical studies suggest that TU-100 is beneficial for postoperative complications, especially ileus and abdominal bloating, and there has been a recent surge in scientifically robust data from basic and clinical studies for some of the Kampo medicines, e.g., daikenchuto (TU- 100).
Abstract: Herbal medicines have been used in Japan for more than 1500 years and traditional Japanese medicines (Kampo medicines) are now fully integrated into the modern healthcare system In total, 148 Kampo formulae are officially approved as prescription drugs and covered by the national health insurance system in Japan However, despite their long track record of clinical use, the multi-targeted, multi-component properties of Kampo medicines, which are fundamentally different from Western medicines, have made it difficult to create a suitable framework for conducting well-designed, large-scale clinical trials In turn, this has led to misconceptions among western trained physicians concerning the paucity of scientific evidence for the beneficial effects of Kampo medicines Fortunately, there has been a recent surge in scientifically robust data from basic and clinical studies for some of the Kampo medicines, eg, daikenchuto (TU-100) Numerous basic and clinical studies on TU-100, including placebo-controlled double-blind studies for various gastrointestinal disorders, and absorption, distribution, metabolism and excretion (ADME) studies, have been conducted or are in the process of being conducted in both Japan and the USA Clinical studies suggest that TU-100 is beneficial for postoperative complications, especially ileus and abdominal bloating ADME and basic studies indicate that the effect of TU-100 is a composite of numerous actions mediated by multiple compounds supplied via multiple routes In addition to known mechanisms of action via enteric/sensory nerve stimulation, novel mechanisms via the TRPA1 channel and two pore domain potassium channels have recently been elucidated TU-100 compounds target these channels with and without absorption, both before and after metabolic activation by enteric flora, with different timings and possibly with synergism
60 citations
TL;DR: It is shown that interferon γ (IFN-γ) stimulates ubiquitin and p62 recruitment to T. gondii parasitophorous vacuoles (PVs) and that p62 deficiency in antigen-presenting cells (APCs) and mice diminishes the robust IFn-γ-primed activation of CD8(+) T cells that recognize the T. Gondii-derived antigen secreted into PVs.
59 citations
TL;DR: Hydroxy-α sanshool (HAS), a readily absorbable active ingredient of TU-100 and a KCNK3/KCNK9/ KCNK18 blocker as well as TRPV1/TRPA1 agonist, has been investigated for its effects on colonic motility.
Abstract: Various colonic motor activities are thought to mediate propulsion and mixing/absorption of colonic content. The Japanese traditional medicine daikenchuto (TU-100), which is widely used for postoperative ileus in Japan, accelerates colonic emptying in healthy humans. Hydroxy-α sanshool (HAS), a readily absorbable active ingredient of TU-100 and a KCNK3/KCNK9/KCNK18 blocker as well as TRPV1/TRPA1 agonist, has been investigated for its effects on colonic motility. Motility was evaluated by intraluminal pressure and video imaging of rat proximal colons in an organ bath. Distribution of KCNKs was investigated by RT-PCR, in situ hybridization, and immunohistochemistry. Current and membrane potential were evaluated with use of recombinant KCNK3- or KCNK9-expressing Xenopus oocytes and Chinese hamster ovary cells. Defecation frequency in rats was measured. HAS dose dependently induced strong propulsive “squeezing” motility, presumably as long-distance contraction (LDC). TRPV1/TRPA1 agonists induced different motility patterns. The effect of HAS was unaltered by TRPV1/TRPA1 antagonists and desensitization. Lidocaine (a nonselective KCNK blocker) and hydroxy-β sanshool (a geometrical isomer of HAS and KCNK3 blocker) also induced colonic motility as a rhythmic propagating ripple (RPR) and a LDC-like motion, respectively. HAS-induced “LDC,” but not lidocaine-induced “RPR,” was abrogated by a neuroleptic agent tetrodotoxin. KCNK3 and KCNK9 were located mainly in longitudinal smooth muscle cells and in neural cells in the myenteric plexus, respectively. Administration of HAS or TU-100 increased defecation frequency in normal and laparotomy rats. HAS may evoke strong LDC possibly via blockage of the neural KCNK9 channel in the colonic myenteric plexus.
44 citations
TL;DR: It is shown that a class IV semaphorin, SEMA4A, regulates CD8+ T cell activation and differentiation through activation of mTOR complex (mTORC) 1, and that plexin B2 is a functional receptor of SEMA 4A in CD8- T cells.
Abstract: Mammalian target of rapamycin (mTOR) plays crucial roles in activation and differentiation of diverse types of immune cells. Although several lines of evidence have demonstrated the importance of mTOR-mediated signals in CD4+ T cell responses, the involvement of mTOR in CD8+ T cell responses is not fully understood. In this study, we show that a class IV semaphorin, SEMA4A, regulates CD8+ T cell activation and differentiation through activation of mTOR complex (mTORC) 1. SEMA4A−/− CD8+ T cells exhibited impairments in production of IFN-γ and TNF-α and induction of the effector molecules granzyme B, perforin, and FAS-L. Upon infection with OVA-expressing Listeria monocytogenes, pathogen-specific effector CD8+ T cell responses were significantly impaired in SEMA4A−/− mice. Furthermore, SEMA4A−/− CD8+ T cells exhibited reduced mTORC1 activity and elevated mTORC2 activity, suggesting that SEMA4A is required for optimal activation of mTORC1 in CD8+ T cells. IFN-γ production and mTORC1 activity in SEMA4A−/− CD8+ T cells were restored by administration of recombinant Sema4A protein. In addition, we show that plexin B2 is a functional receptor of SEMA4A in CD8+ T cells. Collectively, these results not only demonstrate the role of SEMA4A in CD8+ T cells, but also reveal a novel link between a semaphorin and mTOR signaling.
39 citations
TL;DR: It is shown that the recruitment of NF-κB, RNA polymerase, and the TATA-binding protein is MyD88-dependent only at secondary response genes, and mechanistic distinctions advance the understanding of the diverse molecular cascades that underlie the differential regulation of pro-inflammatory genes.
30 citations
TL;DR: Rab GDP dissociation inhibitor α (RabGDIα), originally identified as a Rab small GTPase inhibitor, is a negative regulator of IFN-γ–inducible GTPases in cell-autonomous immunity to the intracellular pathogen Toxoplasma gondii.
Abstract: IFN-γ orchestrates cell-autonomous host defense against various intracellular vacuolar pathogens. IFN-γ–inducible GTPases, such as p47 immunity-related GTPases (IRGs) and p65 guanylate-binding proteins (GBPs), are recruited to pathogen-containing vacuoles, which is important for disruption of the vacuoles, culminating in the cell-autonomous clearance. Although the positive regulation for the proper recruitment of IRGs and GBPs to the vacuoles has been elucidated, the suppressive mechanism is unclear. Here, we show that Rab GDP dissociation inhibitor α (RabGDIα), originally identified as a Rab small GTPase inhibitor, is a negative regulator of IFN-γ–inducible GTPases in cell-autonomous immunity to the intracellular pathogen Toxoplasma gondii. Overexpression of RabGDIα, but not of RabGDIβ, impaired IFN-γ–dependent reduction of T. gondii numbers. Conversely, RabGDIα deletion in macrophages and fibroblasts enhanced the IFN-γ–induced clearance of T. gondii. Furthermore, upon a high dose of infection by T. gondii, RabGDIα-deficient mice exhibited a decreased parasite burden in the brain and increased resistance in the chronic phase than did control mice. Among members of IRGs and GBPs important for the parasite clearance, Irga6 and Gbp2 alone were more frequently recruited to T. gondii-forming parasitophorous vacuoles in RabGDIα-deficient cells. Notably, Gbp2 positively controlled Irga6 recruitment that was inhibited by direct and specific interactions of RabGDIα with Gbp2 through the lipid-binding pocket. Taken together, our results suggest that RabGDIα inhibits host defense against T. gondii by negatively regulating the Gbp2–Irga6 axis of IFN-γ–dependent cell-autonomous immunity.
24 citations
TL;DR: The effect of TU‐100 on the intestines is believed to be a composite of multiple actions by multiple compounds supplied via multiple routes, including pepper, ginger, and ginseng.
Abstract: A pharmaceutical grade Japanese traditional medicine, daikenchuto (TU-100), consisting of Japanese pepper, processed ginger, and ginseng, has been widely used for various intestinal disorders in Japan and now under development as a new therapeutic drug in the US. It is suggested that TU-100 ingredients exert pharmacological effects on intestines via two routes, from the luminal side before absorption and the peripheral blood stream after absorption. Therefore, in order to fully understand the pharmacological actions of TU-100, it is critically important to know the intraluminal amounts and forms of ingested TU-100 ingredients. In the present study, after administrating TU-100 to rats, the concentrations of TU-100 ingredients and their conjugates in the peripheral and portal blood and ileal contents were determined by LC-MS/MS. Next, TU-100 was administered to patients with ileostomy bags, but whose small intestines are diagnosed as healthy, and the ingredients/conjugates in the ileal effluent were analyzed. The results suggest that: (1) Pepper ingredients hydroxysanshools are rapidly absorbed and enter systemic circulation, (2) Ginseng ingredients ginsenosides are transported to the colon with the least absorption, (3) Ginger ingredients gingerols are absorbed and some conjugated in the small intestine and transported via the portal vein. While only a small amount of gingerols/gingerol conjugates enter systemic circulation, considerable amounts reappear in the small intestine. Thus, the effect of TU-100 on the intestines is believed to be a composite of multiple actions by multiple compounds supplied via multiple routes.
TL;DR: A novel cell imaging technique to evaluate SMC contractility is established and may facilitate investigation into SMC activity and its role in gastrointestinal motility, and may assist in the discovery of new prokinetic agents.
TL;DR: Data indicate that tramadol and M1 selectively inhibit the function of h TRPA1, but not that of hTRPV1, and that hTRPA1 may play a role in the analgesic effects of these compounds.
Abstract: BACKGROUND:The transient receptor potential vanilloid 1 (TRPV1) and the transient receptor potential ankyrin 1 (TRPA1), which are expressed in sensory neurons, are polymodal nonselective cation channels that sense noxious stimuli. Recent reports showed that these channels play important roles in inf
Journal Article•
TL;DR: After endovascular embolization and surgical interruption of all arteries feeding the DAVF, the dementia reversed and patients should be aware of the possibility of DAVF as the cause of rapidly progressive dementia even if routine MRI reveals no or only minimal abnormality.
Abstract: We describe the case of a 72-year-old man who presented with dementia that had progressed rapidly over a few months. Laboratory analysis of blood and cerebrospinal fluid (CSF) showed no abnormalities, with the exception of a slightly increased CSF protein level. Results of routine magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) and magnetic resonance angiography (MRA) were unremarkable. However, detailed neuroimaging studies including contrast-enhanced T1-weighted MRI and conventional angiography revealed a superior sagittal sinus (SSS) dural arteriovenous fistula (DAVF). After endovascular embolization and surgical interruption of all arteries feeding the DAVF, the dementia reversed. We should be aware of the possibility of DAVF as the cause of rapidly progressive dementia even if routine MRI reveals no or only minimal abnormality.
TL;DR: It is shown that Arf 6, an Arf protein of the small GTPase family, is involved in promoting the myelination process in Schwann cells, adding Arf6 to the list of intracellular signaling molecules involved in the myelinination process.
TL;DR: Fibers in the oculomotor fascicle that innervate the levator palpebrae, superior rectus, and inferior oblique muscles appear to be more susceptible to ischemic damage than those that innservate the pupillary sphincter and inferior rectus muscles.
TL;DR: A 43-year-old Japanese man infected with HIV who exhibited elevated serum creatine kinase and transaminases levels without any symptoms is presented and his condition recovered without side effects related to the metabolic or immunosuppressive effects of these drugs.
Abstract: Human immunodeficiency virus (HIV) infection disturbs the host's immune function and often coexists with various autoimmune and/or systemic rheumatic diseases with manifestations that sometimes overlap with each other. We herein present the case of a 43-year-old Japanese man infected with HIV who exhibited elevated serum creatine kinase and transaminases levels without any symptoms. He was diagnosed with autoimmune hepatitis, polymyositis and Sjogren's syndrome and received combined antiretroviral therapy (cART); however, the laboratory abnormalities persisted. We successfully administered cART with the addition of oral prednisolone, and the patient's condition recovered without side effects related to the metabolic or immunosuppressive effects of these drugs.
TL;DR: The data support the key role of Arf6 in Schwann cell myelination, especially in the initiation, and characterized an another line of small-hairpin (sh)RNA transgenic mice targeting Arf 6.
Patent•
06 Jul 2015
TL;DR: In this paper, a thermogravimetric analysis on the electrode material in an air stream of 100 ml/min at a temperature rise of 5°C/min, the temperature when the weight of the material decrease by 20% of the weight before the rise in temperature is 650°C or below.
Abstract: PROBLEM TO BE SOLVED: To provide an electrode material which enables the formation of a power storage device low in internal resistance at a low temperature and less in quantity of gas generated when it is held in a state of being charged.SOLUTION: An electrode material comprises a carbon material. When performing a thermogravimetric analysis on the electrode material in an air stream of 100 ml/min at a temperature rise of 5°C/min, the temperature when the weight of the material decrease by 20% of the weight before the rise in temperature is 650°C or below.SELECTED DRAWING: None
TL;DR: It is proposed to reconsider recommendation for the treatment duration of 21 days, and meanwhile to evaluate the treatment effect of PCP with Ga-S, because PCP resistance to sulfa drugs, namely are trimethoprim-sulfamethoxazole, is beginning to appear.
Abstract: OBJECTIVE Peumocystis pneumonia (PCP) is one of the common opportunistic infections with severe respiratory failure, and is sometimes life-threatening in patients with the acquired immunodeficiency syndrome. Although treatment for PCP is established, an appropriate treatment period has not been evaluated to clarify the risk factors for immune reconstitution inflammatory syndrome (IRIS) associated with PCP. METHOD We retrospectively analyzed the clinical characteristics of risk factor, which are the treatment period for PCP, and 67Ga scintigraphy (Ga-S) at the 21st day from the start of the treatment for PCP, with 21 cases of PCP and HIV infection treated during 2005-2012 at Kyushu Medical Center. RESULT The rate of residual uptake by Ga-S was assessed in 17 cases (81%). Four cases were diagnosed as being PCP-IRIS, and residual uptake by Ga-S was detected in all PCP-IRIS cases. The durations of the therapy were classified into three groups: 21 days, 28 days, and 35 days. All PCP-IRIS cases were treated in the period of 28 days. In contrast, in 11 cases that showed residual uptake by Ga-S, and were treated for PCP in 35 days, PCP-IRIS did not occur. Additionally, there were 4 cases in which residual uptake by Ga-S did not occur. They were treated with PCP for only 21 days, but did not show PCP-IRIS. CONCLUSION In this study, we showed that Ga-S is useful to evaluate the therapeutic effect. Furthermore, we found that the occurrence of PCP-IRIS could be prevented with the early start of cART after 21 days treatment for PCP, when residual uptake by Ga-S after the first treatment for PCP was not detected. It may also be possible to start cART in the early phase after its treatment without the occurrence of PCP-IRIS with the appropriate additional treatment of PCP for 14 days. These guidelines for treatment of PCP in HIV-infected adults and adolescents have been recommended for the duration of 21 days since 1984. We propose that for the prevention of PCP-IRIS, it is nessecory to reconsider recommendation for the treatment duration of 21 days, and meanwhile to evaluate the treatment effect of PCP with Ga-S, because PCP resistance to sulfa drugs, namely are trimethoprim-sulfamethoxazole, is beginning to appear.
TL;DR: This is the first report in this country of the successful use of IVIG therapy to treat a patient with IgGλ monoclonal gammopathy and related sensory ataxic axonal polyneuropathy, and the patient regained his capacity to walk independently after treatment.
Abstract: We report the case of an 84-year-old man with sensory ataxic polyneuropathy and IgGλ monoclonal gammopathy of undetermined significance (MGUS), which was successfully treated with intravenous immunoglobulin (IVIG) therapy. He had developed progressive ataxic gait over the span of 2 years before he was admitted to our hospital. On admission, he was unable to walk without assistance because of severe sensory ataxia. He performed poorly on the finger-nose-finger and heel-knee tests, and his vibration and position sense in the feet was remarkably diminished. However, motor involvement was not remarkable. Serum immunoelectrophoresis revealed IgGλ monoclonal gammopathy, and MGUS was diagnosed. Nerve conduction studies revealed sensory-dominant axonal polyneuropathy. The patient was successfully treated with IVIG (400 mg/kg/day, for 5 days). He regained his capacity to walk independently after treatment, but his nerve conduction results remained unchanged. This sensory ataxia might be partially due to underlying cervical spondylotic myelopathy. To our knowledge, this is the first report in our country of the successful use of IVIG therapy to treat a patient with IgGλ monoclonal gammopathy and related sensory ataxic axonal polyneuropathy.
TL;DR: It is demonstrated that HLA-class 1 expression in GCA resembles that in Takayasu arteritis, suggesting that these two arteritis types share the same genetic background.
Abstract: Objective To investigate clinical and laboratory features of giant cell arteritis (GCA). Method We included 24 patients (6 men, 18 women; mean age 69.8 years) in this study. GCA was diagnosed based on the American College of Rheumatology 1990 classification criteria. Results Mean serum C-reactive protein was 9.03 mg/dl. GCA was classified into three types: classic temporal arteritis type (cranial GCA, nine patients); large-vessel type, affecting the aorta and its major branches without temporal arteries (12 patients); generalized type, affecting both temporal arteries and large vessels (three patients). Swelling and tenderness of temporal arteries were recognized in temporal arteritis and generalized arteritis. Ten of these patients also had histopathologic findings of arteritis, including giant cells in biopsy specimens. Examination of HLA-class 1 expression showed that one patient with cranial GCA, three with generalized GCA, and seven with large-vessel GCA were positive for HLA-A24, and four patients with large-vessel GCA were positive for HLA-B39. One patient with cranial GCA, one with generalized GCA, and six with large-vessel GCA were positive for HLA-B52. Nine patients were positive for anti-phospholipid antibodies (seven for anti-cardiolipin antibody immunoglobulin G, seven for anti-cardiolipin β2-glycoprotein-1 antibody, one for lupus anticoagulant). Conclusion Our study demonstrated that HLA-class 1 expression in GCA resembles that in Takayasu arteritis, suggesting that these two arteritis types share the same genetic background. In contrast, the difference in the prevalence of anti-phospholipid antibodies in GCA and Takayasu arteritis patients shows a difference in the characteristic aspects of these two arteritis types.
TL;DR: A fully automatic method for detecting the carotid artery from volumetric ultrasound images as a preprocessing stage for building three-dimensional images of the structure of the carOTid artery.
Abstract: We propose a fully automatic method for detecting the carotid artery from volumetric ultrasound images as a preprocessing stage for building three-dimensional images of the structure of the carotid artery. The proposed detector utilizes support vector machine classifiers to discriminate between carotid artery images and non-carotid artery images using two kinds of LBP-based features. The detector switches between these features depending on the anatomical position along the carotid artery. We evaluate our proposed method using actual clinical cases. Accuracies of detection are 100%, 87.5% and 68.8% for the common carotid artery, internal carotid artery, and external carotid artery sections, respectively. key words: ultrasound, carotid artery, detection, support vector machine, local binary patterns