Pleural effusion caused by Trichinella spiralis infection: two case reports.

BACKGROUND: Trichinosis is a worldwide food-borne zoonotic parasitic disease, which is mainly obtained by ingesting undercooked meat containing infected larvae. The purpose of our article is to introduce and discuss two rare cases of pleural effusion caused by Trichinella spiralis. CASE PRESENTATION: Here we described two male patients who presented to the respiratory department of our hospital with a massive unilateral pleural effusion, their serum eosinophils were in the normal range, laboratory serological tests revealed that Trichinella spiralis IgG antibody was positive. After the oral administration of antiparasitic drugs, the pleural effusion of two patients was completely absorbed. CONCLUSION: Both patients were diagnosed with Trichinosis complicated with pleural effusion, which is very rare in the clinic and easy to be misdiagnosed because of normal eosinophils.

Protein deficiency during Trichinella spiralis infection impairs lung immunity against newborn larvae.

The goal of this study was to analyse the effects of a protein-deficient (PD) diet on antibody-dependent cell-mediated cytotoxicity (ADCC) in vitro against newborn larvae (NBL) of Trichinella spiralis in the lungs of infected rats. Two groups of weaning Wistar rats received a PD diet (6.5% casein) and other two received a control diet (C, 20% casein). After ten days, one group of each diet was infected (PDI and CI ) with muscle larvae. Lung tissue extracts (LTE) and lung cell suspension (LCS) were obtained. PDI had lower titres of anti-NBL antibodies in LTE than CI . In ADCC assays using control cells, NBL mortality percentage was lower with LTE from PDI than LTE from CI (P < .01). In assays using control cytotoxic sera, ADCC was exerted by LCS from CI at all days post-infection (p.i.), but only by LCS from 13 days p.i. from PDI . ADCC assays combining LTE and LCS from the same group showed a lower response for PDI than for CI (P < .0001). LCS from PDI contained lower numbers of neutrophils, eosinophils and FcεRI+ cells than CI . PD may diminish ADCC activity against T spiralis NBL in lungs through alterations in specific antibodies and effector cells.

EphrinB2/ephB2-mediated myenteric synaptic plasticity: mechanisms underlying the persistent muscle hypercontractility and pain in postinfectious IBS.

Patients with irritable bowel syndrome (IBS) show pain hypersensitivity and smooth muscle hypercontractility in response to colorectal distension (CRD). Synaptic plasticity, a key process of memory formation, in the enteric nervous system may be a novel explanation. This study aimed to explore the regulatory role of ephrinB2/ephB2 in enteric synaptic plasticity and colonic hyperreactive motility in IBS. Postinfectious (PI)-IBS was induced by Trichinella spiralis infection in rats. Isometric contractions of colonic circular muscle strips, particularly neural-mediated contractions, were recorded ex vivo. Meanwhile, ephrinB2/ephB2-mediated enteric structural and functional synaptic plasticity were assessed in the colonic muscularis, indicating that ephrinB2 and ephB2 were located on enteric nerves and up-regulated in the colonic muscularis of PI-IBS rats. Colonic hypersensitivity to CRD and neural-mediated colonic hypercontractility were present in PI-IBS rats, which were correlated with increased levels of cellular homologous fos protein (c-fos) and activity-regulated cystoskeleton-associated protein (arc), the synaptic plasticity-related immediate early genes, and were ameliorated by ephB2Fc (an ephB2 receptor blocker) or MK801 (an NMDA receptor inhibitor) exposure. EphrinB2/ephB2 facilitated synaptic sprouting and NMDA receptor-mediated synaptic potentiation in the colonic muscularis of PI-IBS rats and in the longitudinal muscle-myenteric plexus cultures, involving the Erk-MAPK and PI3K-protein kinase B pathways. In conclusion, ephrinB2/ephB2 promoted the synaptic sprouting and potentiation of myenteric nerves involved in persistent muscle hypercontractility and pain in PI-IBS. Hence, ephrinB2/ephB2 may be an emerging target for the treatment of IBS.-Zhang, L., Wang, R., Bai, T., Xiang, X., Qian, W., Song, J., Hou, X. EphrinB2/ephB2-mediated myenteric synaptic plasticity: mechanisms underlying the persistent muscle hypercontractility and pain in postinfectious IBS.

Protease Activated Receptor-2 Induces Immune Activation and Visceral Hypersensitivity in Post-infectious Irritable Bowel Syndrome Mice.

BACKGROUND: The role of protease activated receptor-2 (PAR-2) in the pathogenesis of abdominal pain in irritable bowel syndrome (IBS) is not well defined. AIMS: To investigate the role of PAR-2-mediated visceral hypersensitivity in a post-infectious IBS (PI-IBS) mouse model. METHODS: T. spiralis-infected PI-IBS mouse model was used. Fecal serine protease activity and intestinal mast cells were evaluated. Intestinal permeability was assessed by urine lactulose/mannitol ratio, and colonic expressions of PAR-2 and tight junction (TJ) proteins were examined by Western blot. Intestinal immune profile was assessed by measuring Th (T helper) 1/Th2 cytokine expression. Visceral sensitivity was evaluated by abdominal withdrawal reflex in response to colorectal distention. RESULTS: Colonic PAR-2 expression as well as fecal serine protease activity and intestinal mast cell counts were elevated in PI-IBS compared to the control mice. Decreased colonic TJ proteins expression, increased lactulose/mannitol ratio, elevated colonic Th1/Th2 cytokine ratio, and visceral hypersensitivity were observed in PI-IBS compared to the control mice. Administration of PAR-2 agonist in control mice demonstrated similar changes observed in PI-IBS mice, while PAR-2 antagonist normalized the increased intestinal permeability and reduced visceral hypersensitivity observed in PI-IBS mice. CONCLUSIONS: PAR-2 activation increases intestinal permeability leading to immune activation and visceral hypersensitivity in PI-IBS mouse model.

Effects of probiotic supplementation on post-infectious irritable bowel syndrome in rodent model.

BACKGROUND: Probiotics have been reported to be the active component used in the treatment of many functional gastrointestinal symptoms and syndromes. Lactobacillus and yeast culture are extensively used in probiotic supplements and traditional treatments for irritable bowel syndrome (IBS). The aim of this study was to investigate the effects of probiotic treatments (Lactobacillus acidophilus LA5, Bifidobacterium animalis subsp. lactis BB12 and Saccharomyces cerevisiae var. boulardii) on the behavioral response, targeted gene expression and pro-inflammatory cytokine levels of Pi (Post infectious)-IBS -induced mice. METHODS: Pathogen-free male C57L/B6 mice and the Trichinella-infected mice were used to measure the score of abdominal withdrawal reflex (AWR). To compare molecular, biological and biochemical evidences of given probiotics with normal and positive control groups in mice, we conducted quantitative reverse transcription polymerase chain reaction (RT-qPCR), western blotting, and cytokine analysis. RESULTS: Pi-IBS-induced immune response was confirmed that PAR-2 mRNA level was significantly increased by Trichinella infection (P < 0.05). The reduction of Pi-IBS symptoms through Trichinella infection and the effects of given probiotics were confirmed by a change in the protein levels of cytokines (P < 0.05). In addition, the administration of DW (Daewon) probiotics significantly decreased serum levels of IL-1 and IL-6 (P < 0.05). CONCLUSIONS: We have demonstrated that the given probiotics decreased pro-inflammatory cytokine levels in both the control and Pi-IBS induced mice. Taken all the results together, the results support that DW probiotics has a potential as a probiotic medication for patient with IBS via regulating TNF-α and IL-6 protein levels and serum IL-1 and IL-6 levels.

Beneficial effects of Rifaximin in post-infectious irritable bowel syndrome mouse model beyond gut microbiota.

BACKGROUND AND AIMS: Rifaximin is a minimally absorbed antibiotic, which has shown efficacy in irritable bowel syndrome (IBS) patients. However, the mechanism on how it effects in IBS is still incompletely defined. In this study, Trichinella spiralis-infected post-infectious (PI) IBS mouse model was used, to assess the action of rifaximin on visceral hypersensitivity, barrier function, gut inflammation, and microbiota. METHODS: Post-infectious IBS model was established by T. spiralis infection in mice. Rifaximin were administered to PI-IBS mice for seven consecutive days. The abdominal withdrawal reflex and threshold of colorectal distention were employed to evaluate visceral sensitivity. Smooth muscle contractile response was recorded in the organ bath. Intestinal permeability was measured by Ussing chamber. Expression of tight junction protein and cytokines were measured by Western blotting. Ilumina miseq platform was used to analyze bacterial 16S ribosomal RNA. RESULTS: Post-infectious IBS mice treated with rifaximin exhibited decreased abdominal withdrawal reflex score, increased threshold, reduced contractile response, and intestinal permeability. Rifaximin also suppressed the expression of interleukin-12 and interleukin-17 and promoted the expression of the major tight junction protein occludin. Furthermore, rifaximin did not change the composition and diversity, and the study reavealed that rifaximin had a tiny effect on the relative abundance of Lactobacillus and Bifidobacterium in this PI-IBS model. CONCLUSIONS: Rifaximin alleviated visceral hypersensitivity, recovered intestinal barrier function, and inhibited low-grade inflammation in colon and ileum of PI-IBS mouse model. Moreover, rifaximin exerts anti-inflammatory effects with only a minimal effect on the overall composition and diversity of the gut microbiota in this model.

Molecular identification of Sarcocystis lutrae in the European otter (Lutra lutra) and the European badger (Meles meles) from the Czech Republic.

Muscular sarcosporidial infections by Sarcocystis lutrae (Apicomplexa: Sarcocystidae) from the otter (Lutra lutra) and badger (Meles meles) (Carnivora: Mustelidae) were found in the Czech Republic. As part of a diversity evaluation of Sarcocystis in wild carnivores during 2016-2017, samples of diaphragm, tongue and hind-limb muscles were collected from nine districts, examined by compression and characterized molecularly. Cyst walls were thin, with no visible protrusions, and histological sections of infected muscle tissue showed no host responses. Fourteen of 17 badgers (82% prevalence) and one otter (100% prevalence) were positive for sarcocysts. Sequence analyses at four loci (18S rRNA, 28S rRNA, ITS1 and cox1) confirmed the identity as S. lutrae. This is also the first report of a co-infection with muscular sarcocystosis and Trichinella in badger. The finding of Trichinella is important from the zoonotic point of view, since badgers are used for meat consumption. Similar and future monitoring of both parasitic taxa are needed.

Trichinella Nativa Outbreak With Rare Thrombotic Complications Associated With Meat From a Black Bear Hunted in Northern Ontario.

BACKGROUND: Although trichinellosis is known to cause thrombotic disease, serious thrombotic events are rare and have not been previously associated with Trichinella nativa infection. METHODS: Patient interviews and medical chart reviews were conducted on 10 men who became ill following consumption of a common source of black bear meat. Trichinella serology on patient sera as well as polymerase chain reaction (PCR) and larval identification of the meat samples was conducted. RESULTS: All 10 exposed individuals developed an acute illness clinically compatible with trichinellosis, characterized by fever, abdominal pain, and diarrhea, along with eosinophilia ranging from 0.9 × 109/L to 6.1 × 109/L. Within 2 weeks of the diarrheal illness, systemic symptoms developed in all exposed individuals characterized by fever, myalgia, periorbital edema, and fatigue. ST-elevation myocardial infarction and sinus venous tract thrombosis occurred as a complication of trichinellosis in 2 patients. Acute serology was nonreactive in all patients, though convalescent serology was reactive in 6 of 8 (75%) patients for whom sera was available. Multiplex PCR identified T. nativa from the bear meat, and was corroborated by microscopic larval identification. CONCLUSIONS: We report a 100% attack rate of T. nativa from bear meat among those who were exposed, and demonstrate that this species can cause serious thrombotic complications of trichinellosis in humans. Education of hunters and the public regarding the importance of proper preparation of wild game prior to ingestion is warranted.

Paraoxonase-1 activity is related to Trichinella spiralis-induced hepatitis in rats.

BACKGROUND: Little is known about the potential adverse effects of a chronic zoonotic nematode Trichinella spiralis infection on hepatic inflammation and its relationship to paraoxonase (PON)-1 and butyrylcholinesterase (BuChE) activities. Therefore, we aimed to examine the effects of T. spiralis infection on hepatic synthesis of PON1. METHODS: Wistar rats were infected with 2500 first-stage larvae (L1) of T. spiralis, and serum PON1 and BuChE activities were evaluated. Hepatic expression levels of PON1, BuChE and various cytokines and chemokines [interleukin (IL)-1, IL-4, IL-6, IL-10, tumour necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1α, and transforming growth factor (TGF)-ß1] were evaluated for up to 9 weeks post-infection (p.i.). The effect of these changes on the degree of hepatic apoptosis was also investigated. RESULTS: Trichinella spiralis infection in rats induced significant decreases in serum PON1 activities from day 2 until week 7 p.i. and BuChE activity starting from day 4 until 2 weeks p.i. Moreover, T. spiralis infection increased serum pro-inflammatory cytokines IL-1, IL-6 and TNF-α as well as chemokines MCP-1, MIP-1α and TGF-ß1 during the enteral phase of the parasite life cycle. The anti-inflammatory cytokines IL-4 and IL-10 showed significant increases during the enteral phase for the former and the muscle phase for the latter. These were associated with hepatic inflammation and apoptosis. These events typically decreased hepatic PON1 and BuChE mRNA expression. CONCLUSIONS: Immune responses mounted against T. spiralis infection in rats were associated with hepatic inflammation and a subsequent decrease in serum PON1 and BuChE activities.

Reduced interstitial cells of Cajal and increased intraepithelial lymphocytes are associated with development of small intestinal bacterial overgrowth in post-infectious IBS mouse model.

OBJECTIVE: Intestinal dysmotility and immune activation are likely involved in the pathogenesis of small intestinal bacteria overgrowth (SIBO) in irritable bowel syndrome (IBS). We aimed at investigating the role of interstitial cells of Cajal (ICC) and intestinal inflammation in the development of SIBO using a post-infectious IBS (PI-IBS) mouse model. MATERIALS AND METHODS: NIH mice were randomly infected with Trichinella spiralis. Visceral sensitivity and stool pattern were assessed at 8-weeks post-infection (PI). Intestinal bacteria counts from jejunum and ileum were measured by quantitative real-time PCR to evaluate the presence of SIBO. ICC density, intraepithelial lymphocytes (IELs) counts, and intestinal cytokine levels (IL1-ß, IL-6, toll-like receptor-4 (TLR-4), IL-10) in the ileum were examined. RESULTS: PI-IBS mice demonstrated increased visceral sensitivity compared with the control group. One-third of the PI-IBS mice developed SIBO (SIBO+/PI-IBS) and was more likely to have abnormal stool form compared with SIBO negative PI-IBS (SIBO-/PI-IBS) mice but without difference in visceral sensitivity. SIBO+/PI-IBS mice had decreased ICC density and increased IELs counts in the ileum compared with SIBO-/PI-IBS mice. No difference in inflammatory cytokine expression levels were detected among the groups except for increased TLR-4 in PI-IBS mice compared with the control group. CONCLUSIONS: Development of SIBO in PI-IBS mice was associated with reduced ICC density and increased IELs counts in the ileum. Our findings support the role of intestinal dysmotility and inflammation in the pathogenesis of SIBO in IBS and may provide potential therapeutic targets.

[The colloid milium: An observation associated with trichinosis]. / Milium colloïde : une observation associée à une trichinose.

The colloid milium has four clinical forms: adult colloid milium, juvenile colloid milium, paracolloid (or nodular colloid degeneration) and pigmented colloid milium. We report the case of an adult colloid milium in a man of 56, who presented episodes of diffuse pruritus associated with myalgia and digestive disorders, indicative of trichinosis. He also developed gradually over the past 10 years, yellowish injuries in the mandibles and neck for whom histology objectified a colloid milium. Etiology and treatment are still unknown; association with a trichinosis is probably coincidental.

Changes of cytokine levels in a mouse model of post-infectious irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome (IBS) is a highly prevalent functional gastrointestinal disorder. Post-infectious IBS (PI-IBS) is caused by an acute gastrointestinal infection preceding the onset of symptoms. However, the pathophysiology of PI-IBS is not clear, and the purpose of this study was to investigate the probable immune mechanisms of PI-IBS. METHODS: C57BL/6 mice were randomly assigned to either an infection group or a control group. Mice in the infection group were infected with Trichinella spiralis to establish a model of PI-IBS (500 Trichinella), while control mice received only salt solution. Visceral sensitivity of colorectal distention in mice was evaluated by abdominal withdrawal reflex scores and intestinal inflammation was assessed using hematoxylin-eosin staining; at day 56 post-infection, the mRNA and protein levels of specific cytokines in the gut segments were detected using reverse-transcription polymerase chain reaction and enzyme-linked immunoabsorbent assay. RESULTS: Levels of interferon γ and interleukin (IL)-17 in the PI-IBS group were significantly increased in the duodenum and ileum, and IL-10 was decreased in the jejunum, ileum, and colon compared with control mice. However, the expression level of IL-1ß was not significantly different between the two groups. CONCLUSIONS: The present study suggests that the local low-grade inflammation and immune activation that are an important component of the pathophysiology of PI-IBS are primarily induced and maintained by specific cytokines.

Eosinophilic Pleural Effusion Secondary to Trichinella spiralis Infection in a Patient with Systemic Sclerosis: A Case Report.

BACKGROUND Scleroderma is a chronic autoimmune disease characterized by angiopathy, autoimmunity, and fibrosis. One form of scleroderma, systemic sclerosis, is characterized by diffuse skin lesions and visceral involvement. Eosinophilic pleural effusion is a rare complication attributed to a large array of diseases. We present a case of a man with underlying systemic sclerosis who developed eosinophilic pleural effusion as a complication of associated Trichinella spiralis infection. CASE REPORT A 49-year-old man presented for bilateral inflammatory radio-ulnar-carpal joint pain, paresthesia of the hands and forearms and a 2-week history of right posterior aching thoracic pain and night sweats. The physical examination revealed sclerodermatous skin involvement of the hands, forearms, and forehead, sclerodactyly, Raynaud's phenomenon, and telangiectasias, together with muffled cardiac sounds and right basal abolishment of the vesicular breath sounds. Imagistic evaluation showed the presence of pleuro-pericardial fluid. A thoracocentesis highlighted the presence of an exudative eosinophilic pleural effusion. Laboratory findings showed leukocytosis, with elevated neutrophil and eosinophil counts. The patient was tested for a parasitic infection, but initially the results were negative. He started anti-inflammatory treatment, but no reduction of the pleural fluid was observed. Subsequent evaluation revealed specific anti-trichinella IgG antibodies. Albendazole and corticosteroid therapy were initiated, which resulted in remission of the symptoms. CONCLUSIONS This report highlights the possibility of developing rare or even not-until-now seen complications when 2 etiologically different diseases are associated. The physician should carefully assess the situation to find and resolve the underlying causes.

Effect of nematode Trichinella infection on glucose tolerance and status of macrophage in obese mice.

We investigated the effect of Trichinella infection on glucose tolerance and (pro- or anti-inflammatory) macrophage status in adipose tissue. Ob/ob mice and high fat-fed mice (obesity model) and C57/BL mice (control mice) were orally infected with (infected group) or without (uninfected group) 400 Trichinella per mouse. Four weeks later, the mice were subjected to investigation, which showed that fasting plasma glucose levels decreased in the infected group of C57/BL and ob/ob mice. Glucose tolerance, evaluated with intraperitoneal GTT, improved in the infected group of ob/ob mice and high fat-fed mice compared with the uninfected groups. Additional assay included anti-inflammatory macrophage (M2) markers and pro-inflammatory macrophage (M1) markers, with the aim to explore the effect of Trichinella infection on adipose tissue inflammation, since our previous study identified anti-inflammatory substances in secreted proteins by Trichinella. The result showed that mRNA levels of M2 markers, such as CD206, arginase and IL-10, increased, whereas M1 markers, such as CD11c, iNOS and IL-6, decreased in the stromal vascular fraction (SVF) isolated from epididymal fat in ob/ob mice. Residential macrophages obtained from the peritoneal lavage exhibited lower M1 markers and higher M2 markers levels in the infected group than in the uninfected group. Trichinella infection increases the ratio of M2/M1 systemically, which results in an improvement in pro-inflammatory state in adipose tissue and amelioration of glucose tolerance in obese mice.

[Analysis of distribution and pathological characteristics of 9 fatal trichinosis cases in Yunnan].

OBJECTIVE: To explore forensic pathology features of the fatal trichinosis cases and to summarize the population distribution characteristics of trichinosis in Yunnan. METHODS: Nine recent fatal trichinosis cases were collected from the Forensic Science Identification Center of Kunming Forensic Hospital. Pathological and epidemiological characteristics of trichinosis were analyzed. RESULTS: The nine cases were all died in heart failure due to myocarditis. Among them, 1 case was complicated by encephalitis and 3 cases were complicated by pneumonia. The population mainly involved Bai and Dai nationalities. The geographic distribution was concentrated in Dali, Dehong, Lincang, Xishuangbanna, etc. The cases commonly appeared in winter and spring. CONCLUSION: The cause of trichinosis is closely due to the habit of eating raw pork. It can be diagnosis through the pathological changes of the muscle system in the death cases.

Adenosine 2A receptor contributes to the facilitation of post-infectious irritable bowel syndrome by γδ T cells via the PKA/CREB/NF-κB signaling pathway.

BACKGROUND: Immunological dysfunction-induced low-grade inflammation is regarded as one of the predominant pathogenetic mechanisms in post-infectious irritable bowel syndrome (PI-IBS). γδ T cells play a crucial role in innate and adaptive immunity. Adenosine receptors expressed on the surface of γδ T cells participate in intestinal inflammation and immunity regulation. AIM: To investigate the role of γδ T cell regulated by adenosine 2A receptor (A2AR) in PI-IBS. METHODS: The PI-IBS mouse model has been established with Trichinella spiralis (T. spiralis) infection. The intestinal A2AR and A2AR in γδ T cells were detected by immunohistochemistry, and the inflammatory cytokines were measured by western blot. The role of A2AR on the isolated γδ T cells, including proliferation, apoptosis, and cytokine production, were evaluated in vitro. Their A2AR expression was measured by western blot and reverse transcription polymerase chain reaction (RT-PCR). The animals were administered with A2AR agonist, or A2AR antagonist. Besides, γδ T cells were also injected back into the animals, and the parameters described above were examined, as well as the clinical features. Furthermore, the A2AR-associated signaling pathway molecules were assessed by western blot and RT-PCR. RESULTS: PI-IBS mice exhibited elevated ATP content and A2AR expression (P < 0.05), and suppression of A2AR enhanced PI-IBS clinical characteristics, indicated by the abdominal withdrawal reflex and colon transportation test. PI-IBS was associated with an increase in intestinal T cells, and cytokine levels of interleukin-1 (IL-1), IL-6, IL-17A, and interferon-α (IFN-α). Also, γδ T cells expressed A2AR in vitro and generated IL-1, IL-6, IL-17A, and IFN-α, which can be controlled by A2AR agonist and antagonist. Mechanistic studies demonstrated that the A2AR antagonist improved the function of γδ T cells through the PKA/CREB/NF-κB signaling pathway. CONCLUSION: Our results revealed that A2AR contributes to the facilitation of PI-IBS by regulating the function of γδ T cells via the PKA/CREB/NF-κB signaling pathway.

The "starry night" (diffuse microcalcific myopathy) - thousands of muscle microcalcifications after 30 years of Trichinella infection detected by ultrasound.

Trichinellosis, a parasitosis transmitted through consumption of raw or undercooked meat from pigs and game animals, is responsible for a specific myositis. The calcifications of infected myocytes and larva can be detected during many years postin-fection. We present the case of a male patient with a history of severe trichinellosis with disease onset 30 years ago, presenting with generalized muscle microcalcifications detected during musculoskeletal ultrasound evaluation. The ultrasound aspect of the muscles was indeed spectacular; hence, the comparison with a "starry night".

Characteristics of intestinal lamina propria dendritic cells in a mouse model of postinfectious irritable bowel syndrome.

BACKGROUND AND AIM: Postinfectious irritable bowel syndrome (PI-IBS), which results from inflammation has been emphasized a lot recently. Dendritic cells (DCs) may contribute to intestinal mucosal immune activation in the pathogenesis of PI-IBS. This study tested the hypothesis that phenotype and function of intestinal lamina propria DCs (LPDCs) changed in the development of a PI-IBS mouse model. METHODS: Mice infected with Trichinella spiralis underwent abdominal withdrawal reflex (AWR) to evaluate visceral sensitivity. LPDCs were isolated and purified by intestine digestion and magnetic label-based technique. Surface markers were analyzed by flow cytometry. Endocytic activity, mixed lymphocyte reaction (MLR) and chemotaxis were studied. Cytokine production of the LPDCs cocultured with CD4(+) T cells was determined. RESULTS: Intestinal inflammation resolved after 8 weeks infection with sustained visceral hyperalgesia. Surface markers CD86 and MHCII were lower in the acute infection group, but increased in the PI-IBS stage. Enhanced ability of endocytic activity and decreased abilities to attract and stimulate CD4(+) T cell proliferation were in the acute infection group. However, LPDCs in the PI-IBS stage showed weakened endocytic ability with enhanced abilities to attract and stimulate CD4(+) T cell proliferation. Cocultured LPDCs with CD4(+) T cells showed a predominant Th2 response in the acute infection stage, and more important roles of Th1, Th17 responses in the PI-IBS stage. CONCLUSIONS: The hypothesis was supported that the phenotype and function of LPDCs changed in the development of PI-IBS, which induced the maintenance of intestinal mucosal immune activation and might provide a clue for the treatment of the disease.

Vesicular glutamate transporter-3 contributes to visceral hyperalgesia induced by Trichinella spiralis infection in rats.

BACKGROUND: According to a recent study, vesicular glutamate transporter-3 (VGLUT3) contributes to injury-induced mechanical hyperalgesia in mice. AIMS: The aims of the study were to investigate whether VGLUT3 is involved in visceral pain, and whether transient intestinal infection or acute cold restraint stress (ACRS) affects VGLUT3 expression levels in rats. METHODS: Changes in VGLUT3 and c-Fos proteins were evaluated in rats which received noxious colorectal distension (CRD) stimulation. Transient intestinal infection was effected by oral administration of Trichinella spiralis (T. spiralis) larvae in Brown Norway rats. On the 100th day post-infection (PI), half of the PI-rats and non infected controls were subjected to an ACRS procedure. The visceromotor response to CRD was measured using the abdominal withdrawal reflex (AWR) score. Immunofluorescence and western blot analysis were used to estimate the expression of VGLUT3 in both peripheral and central neurons. RESULTS: Noxious stimulation induced a significant increase in the expression of VGLUT3 in the L6S1 spinal dorsal horn. Compared with the control group, the pain threshold was significantly decreased in the ACRS, PI, and PI + ACRS groups. VGLUT3 expression in the L6S1 dorsal root ganglion (DRG) and spinal neurons were significantly increased in PI and PI + ACRS groups as compared with the control group. CONCLUSIONS: VGLUT3 is involved in conduction of visceral pain sensation and in visceral hyperalgesia induced by Trichinella spiralis infection in rats.