Trichinellosis is a parasitic zoonosis of public health importance. It is caused by Trichinella spiralis which has a wide host range including humans. In the present communication, the ELISA technique was employed on a total of 803 blood samples from 7 selected pig breeding farms in 1996 for diagnosis and surveillance of trichinellosis. Out of the entire 803 samples, nine were found to be suspected while one was positive by ELISA. But western blot analyses employed for further confirmation have shown that all of 10 samples did not react to larval excretory-secretory product antigens. These results indicate that pig breeding farms included in the present study are free from trichinellosis. However, it does not mean Korea is free from trichinellosis since human trichinellosis has recently been reported. The necessity of continued surveillance for trichinellosis in both pigs and wild animals was discussed.
Animals ; *Animals, Domestic ; Antibodies, Helminth/*blood ; Biological Markers/blood ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Human ; Korea/epidemiology ; Swine ; Swine Diseases/*diagnosis/epidemiology ; Trichinella spiralis/*immunology ; Trichinosis/*diagnosis/epidemiology/*veterinary

In order to know the effect of pre-existing Trichinella spiralis infection on experimentally induced intestinal inflammation and immune responses, we induced colitis in T. spiralis-infected mice and observed the severity of colitis and the levels of Th1, Th2, and regulatory cytokines and recruitment of CD4+CD25+Foxp3+ T (regulatory T; Treg) cells. Female C57BL/6 mice were infected with 250 muscle larvae; after 4 weeks, induction of experimental colitis was performed using 3% dextran sulfate sodium (DSS). During the induction period, we observed severity of colitis, including weight loss and status of stool, and evaluated the disease activity index (DAI). A significantly low DAI and degree of weight loss were observed in infected mice, compared with uninfected mice. In addition, colon length in infected mice was not contracted, compared with uninfected mice. We also observed a significant increase in production of pro-inflammatory cytokines, IL-6 and IFN-gamma, in spleen lymphocytes treated with DSS; however, such an increase was not observed in infected mice treated with DSS. Of particular interest, production of regulatory cytokines, IL-10 and transforming growth factor (TGF)-beta, in spleen lymphocytes showed a significant increase in mice infected with T. spiralis. A similar result was observed in mesenteric lymph nodes (MLN). Subsets of the population of Treg cells in MLN and spleen showed significant increases in mice infected with T. spiralis. In conclusion, T. spiralis infection can inhibit the DSS-induced colitis in mice by enhancing the regulatory cytokine and Treg cells recruitment.
Animals ; Colitis/chemically induced/*immunology/pathology ; Cytokines/genetics/*immunology/metabolism ; Dextran Sulfate/adverse effects ; Disease Models, Animal ; Female ; Forkhead Transcription Factors/immunology/metabolism ; *Gene Expression Regulation ; Larva ; Mice ; Mice, Inbred C57BL ; Spleen/immunology ; T-Lymphocytes, Regulatory/*immunology ; Trichinella spiralis/*immunology ; Trichinellosis/*immunology/parasitology

In order to get a better understanding of the role of protease-activated receptor 2 (PAR2) in type 2 helper T (Th2) cell responses against Trichinella spiralis infection, we analyzed Th2 responses in T. spiralis-infected PAR2 knockout (KO) mice. The levels of the Th2 cell-secreted cytokines, IL-4, IL-5, and IL-13 were markedly reduced in the PAR2 KO mice as compared to the wild type mice following infection with T. spiralis. The serum levels of parasite-specific IgE increased significantly in the wild type mice as the result of T. spiralis infection, but this level was not significantly increased in PAR2 KO mice. The expression level of thymic stromal lymphopoietin, IL-25, and eotaxin gene (the genes were recently known as Th2 response initiators) of mouse intestinal epithelial cells were increased as the result of treatment with T. spiralis excretory-secretory proteins. However, the expression of these chemokine genes was inhibited by protease inhibitor treatments. In conclusion, PAR2 might involve in Th2 responses against T. spiralis infection.
Animals ; Antibodies, Helminth/blood ; Chemokine CCL11/biosynthesis ; Cytokines/biosynthesis ; Female ; Gene Expression Profiling ; Immunoglobulin E/blood ; Interleukin-13/secretion ; Interleukin-4/secretion ; Interleukin-5/secretion ; Interleukins/biosynthesis ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Receptor, PAR-2/*metabolism ; Th2 Cells/*immunology ; Trichinella spiralis/*immunology ; Trichinellosis/*immunology

The 5th outbreak of trichinosis occurred in a mountainous area of North Vietnam in 2012, involving 24 patients among 27 people who consumed raw pork together. Six of these patients visited several hospitals in Hanoi for treatment. Similar clinical symptoms appeared in these patients within 5-8 days after eating infected raw pork, which consisted of fever, muscle pain, difficult moving, edema, difficult swallowing, and difficult breathing. ELISA revealed all (6/6) positive reactions against Trichinella spiralis antigen and all cases showed positive biopsy results for Trichinella sp. larvae in the muscle. The larvae detected in the patients were identified as T. spiralis (Vietnamese strain) by the molecular analysis of the mitochondrial cytochrome c oxidase subunit III (cox3) gene.
Adult ; Animals ; Antigens, Helminth/analysis/immunology ; *Disease Outbreaks ; Electron Transport Complex IV/genetics ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Larva ; Male ; Meat/*parasitology ; Mitochondria/genetics ; Muscles/parasitology/pathology ; Swine ; Trichinella spiralis/genetics/immunology/*isolation & purification ; Trichinellosis/*epidemiology/parasitology/pathology ; Vietnam/epidemiology

BACKGROUNDMast cells are implicated in the development of irritable bowel syndrome (IBS), which is associated with the activation of the "neural-immune" system. The aim of this study was to investigate the role of mast cells in the remodeling of cholinergic and peptidergic neurotransmitters induced by acute cold restriction stress (ACRS) post infection (PI) using mast cell deficient rats (Ws/Ws) and their wild-type controls (+/+).

METHODSTransient intestinal infection was initiated by giving 1500 Trichinella spiralis (T.S.) larvae by gavage. ACRS was induced for 2 hours at day 100 PI. Samples of terminal ilea were prepared for H&E staining, mast cell counting and activation and assessment of IL-1beta and IL-10.

RESULTSWhen infected, both strains of rats experienced an acute infectious stage followed by a recovery. Histological scores were significantly higher in infected rats compared with those of the non-infected controls at day 10 PI (10 day-PI vs. control: +/+: 2.75+/-0.17 vs. 0.42+/-0.09; Ws/Ws: 2.67+/-0.67 vs. 0.50+/-0.34; P<0.01). In +/+ rats, post-infection ACRS induced the formation of low-grade inflammation, represented by the imbalance of IL-1beta and IL-10 (IL-1beta: PI+ACRS vs. control: (1812.24+/-561.61) vs. (1275.97+/-410.21) pg/g, P<0.05; IL-10: PI+ACRS vs. control: (251.9+/-39.8) vs. (255.3+/-24.7) pg/g, P>0.05), accompanied by hyperplasia and activation of mast cells (PI+ACRS vs. control: 58.8+/-19.2 vs. 28.0+/-7.6; P<0.01). The balance between acetylcholine (ACh) and substance P (SP) was also disturbed (ACh: PI+ACRS vs. control: (743.94+/-238.72) vs. (1065.68+/-256.46) pg/g, P<0.05; SP: PI+ACRS vs. control: (892.60+/-231.12) vs. (696.61+/-148.61) pg/g, P<0.05). Nevertheless, similar changes of IL-1beta/IL-10 and ACh/SP were not detected in Ws/Ws rats.

CONCLUSIONThe imbalance of ACh/SP, together with the activation of mucosal immunity induced by post-infection ACRS were lacking in mast cell deficient rats, which supports the premise that mast cells play an important role in cholinergic and peptidergic remodeling in the ileum of rats.

Acetylcholine ; metabolism ; Animals ; Enzyme-Linked Immunosorbent Assay ; Ileum ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-1beta ; metabolism ; Intestines ; immunology ; metabolism ; parasitology ; Male ; Mast Cells ; cytology ; metabolism ; physiology ; ultrastructure ; Microscopy, Electron, Transmission ; Neurotransmitter Agents ; metabolism ; Radioimmunoassay ; Rats ; Substance P ; metabolism ; Trichinella spiralis ; physiology ; Trichinellosis ; immunology