The immune response against Trichinella spiralis at the intestinal level depends on the CD4⁺ T cells, which can both suppress or promote the inflammatory response through the synthesis of diverse cytokines. During the intestinal phase, the immune response is mixed (Th1/Th2) with the initial predominance of the Th1 response and the subsequent domination of Th2 response, which favor the development of intestinal pathology. In this context, the glucocorticoids (GC) are the pharmacotherapy for the intestinal inflammatory response in trichinellosis. However, its therapeutic use is limited, since studies have shown that treatment with GC suppresses the host immune system, favoring T. spiralis infection. In the search for novel pharmacological strategies that inhibit the Th1 immune response (proinflammatory) and assist the host against T. spiralis infection, recent studies showed that resiniferatoxin (RTX) had anti-inflammatory activity, which decreased the serum levels of IL-12, INF-γ, IL-1β, TNF-α, NO, and PGE₂, as well the number of eosinophils in the blood, associated with decreased intestinal pathology and muscle parasite burden. These researches demonstrate that RTX is capable to inhibit the production of Th1 cytokines, contributing to the defense against T. spiralis infection, which places it as a new potential drug modulator of the immune response.
Cytokines ; Drug Therapy ; Eosinophils ; Glucocorticoids ; Immune System ; Inflammation* ; Interleukin-12 ; Parasites ; Pathology ; T-Lymphocytes ; Therapeutic Uses* ; Trichinella spiralis ; Trichinellosis*

Trichinellosis transmission to humans via the consumption of reptile meat is rare worldwide. In Korea, however, 2 such outbreaks, possibly via consumption of soft-shelled turtle meat, have occurred in 2 successive years. In 17 August 2014, 6 patients were admitted to Wonju Severance Christian Hospital complaining of myalgia, fever, and headache. Eosinophilia was the indication of the initial laboratory results, and they were eventually diagnosed as trichinellosis by ELISA. All of the patients worked at the same company and had eaten raw soft-shelled turtle meat at a company dinner 10 days prior to their admission. They were treated with albendazole for 2 weeks, upon which all of their symptoms disappeared. This is the 8th report on human trichinellosis in Korea, and the second implicating raw soft-shelled turtle meat.
Adult ; Animals ; Antibodies, Helminth/blood ; Disease Outbreaks ; Female ; Humans ; Male ; Meat/*parasitology ; Republic of Korea ; Trichinella/immunology/isolation & purification/physiology ; Trichinellosis/blood/diagnosis/*parasitology ; Turtles/*parasitology

In Trichinella spiralis infection, type 2 helper T (Th2) cell-related and regulatory T (T(reg)) cell-related immune responses are the most important immune events. In order to clarify which Toll-like receptors (TLRs) are closely associated with these responses, we analyzed the expression of mouse TLR genes in the small intestine and muscle tissue during T. spiralis infection. In addition, the expression of several chemokine- and cytokine-encoding genes, which are related to Th2 and T(reg) cell mediated immune responses, were analyzed in mouse embryonic fibroblasts (MEFs) isolated from myeloid differentiation factor 88 (MyD88)/TIR-associated proteins (TIRAP) and Toll receptor-associated activator of interferons (TRIF) adapter protein deficient and wild type (WT) mice. The results showed significantly increased TLR4 and TLR9 gene expression in the small intestine after 2 weeks of T. spiralis infection. In the muscle, TLR1, TLR2, TLR5, and TLR9 gene expression significantly increased after 4 weeks of infection. Only the expression of the TLR4 and TLR9 genes was significantly elevated in WT MEF cells after treatment with excretory-secretory (ES) proteins. Gene expression for Th2 chemokine genes were highly enhanced by ES proteins in WT MEF cells, while this elevation was slightly reduced in MyD88/TIRAP-/- MEF cells, and quite substantially decreased in TRIF-/- MEF cells. In contrast, IL-10 and TGF-beta expression levels were not elevated in MyD88/TIRAP-/- MEF cells. In conclusion, we suggest that TLR4 and TLR9 might be closely linked to Th2 cell and T(reg) cell mediated immune responses, although additional data are needed to convincingly prove this observation.
Animals ; Gene Expression ; Humans ; Interleukin-10/genetics ; Mice ; Mice, Knockout ; Th2 Cells/metabolism ; Toll-Like Receptors/*genetics/metabolism ; Trichinella spiralis/genetics/*physiology ; Trichinellosis/genetics/metabolism/*parasitology

Here, we present a rare case of cardiac parasitic infection found in an adult female patient who had the symptoms of dyspnea upon exertion. She was diagnosed with a double-chambered right ventricle due to infundibular hypertrophy confirmed by transthoracic echocardiography and cardiac computed tomography. We performed surgery of infundibulectomy around the pulmonary valve. In the end, histopathological findings of the resected infundibular muscle demonstrated trichinellosis, a type of roundworm infection.
Adult ; Dyspnea ; Echocardiography ; Female ; Heart Ventricles* ; Humans ; Hypertrophy ; Pulmonary Valve ; Trichinellosis*

Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5+/-41.0 for T. papuae, 432.6+/-48 for T. pseudospiralis, and 528.6+/-20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp.
Animals ; *Animals, Laboratory ; Cricetinae ; *Disease Susceptibility ; Gerbillinae ; Intestines/parasitology ; Male ; Mice ; Muscles/parasitology ; Parasite Load ; Rats ; Rodent Diseases/*parasitology/pathology ; Trichinella/*growth & development ; Trichinellosis/parasitology/pathology/*veterinary

In intestinal helminth infections, Th2 immune respones are generally associated with mucin secretion for worm expulsion from the host intestine. In particular, IL-4 and IL-13 are the important cytokines related with intestinal mucus production via STAT6 signalling in nematode infections. However, this perspective has never been studied in Gymnophalloides seoi infection. The present study aimed to observe the STAT6 signalling and cytokine responses in C57BL/6 mice, a mouse strain resistant to infection with this trematode. The results showed that worm expulsion occurred actively during days 1-2 post-infection (PI), when goblet cells began to proliferate in the small intestine. The STAT6 gene expression in the mouse spleen became remarkable from day 2 PI. Moreover, G. seoi infection induced a significant increase of IL-13 from day 4 PI in the spleen of infected mice. Our results suggested that goblet cell hyperplasia and worm expulsion in G. seoi-infected mice should be induced by STAT6 signalling, in which IL-13 may be involved as a dominant triggering cytokine.
Animals ; Crassostrea ; Female ; Goblet Cells/*pathology ; Hyperplasia/pathology ; Interleukin-13/*metabolism ; Interleukin-4/*metabolism ; Intestine, Small/immunology ; Metacercariae ; Mice ; Mice, Inbred C57BL ; STAT6 Transcription Factor/*metabolism ; Signal Transduction ; Specific Pathogen-Free Organisms ; Spleen/immunology ; Trematoda/*immunology ; Trichinellosis/*immunology/parasitology

OBJECTIVETo study the effect of Trichinella spiralis (T.spiralis) infection on the expression and distribution of colonic epithelial E-cadherin in mice and its mechanism.

METHODSBALB/c mice and STAT6-/- mice were infected with T.spiralis, and mice without infection were used as control. Seven days later, the horseradish peroxidase (HRP) was infused by rectal enema. Serum HRP was detected in the subsequent 0, 60 and 120 minutes. Then the mice were sacrificed and colon was taken out. The distribution of E-cadherin in colon was detected by immunofluorescence staining, and the expression of E-cadherin was detected by Western blot. The expression of interleukin-4 (IL-4) in mesenteric lymph nodes was detected by ELISA.

RESULTSSerum HRP level in infected BALB/c mice was significantly higher than that in control mice (P<0.05), while it was not significantly different between infected STAT6-/- mice and controls (P>0.05). In infected BALB/c mice, E-cadherin located in cytoplasm of colonic epithelial cells, while in controls, it located in cellular membrane. E-cadherin expression down-regulated significantly in infected BALB/c mice as compared to controls. E-cadherin expression and distribution did not change obviously in infected STAT6-/- and control mice. IL-4 level in mesenteric lymph nodes of infected BALB/c mice [(193.0±12.5) μg/L] was significantly higher as compared to control BALB/c and infected STAT6-/- mice [(21.0±2.3) μg/L and (15.0±3.1) μg/L, all P<0.05].

CONCLUSIONT.spiralis infection can increase colonic epithelial permeability of mice, which may be associated with induction of Th2 cytokine secretion.

Animals ; Cadherins ; metabolism ; Colon ; metabolism ; Disease Models, Animal ; Female ; Interleukin-4 ; metabolism ; Intestinal Diseases, Parasitic ; metabolism ; Intestinal Mucosa ; metabolism ; Lymph Nodes ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Knockout ; Trichinella spiralis ; Trichinellosis ; metabolism

Trichinosis is a parasitic zoonosis caused by the nematode Trichinella spiralis. Anthelmintics are used to eliminate intestinal adults as well as tissue-migrating and encysted larvae. This study aimed to investigate the effects of ivermectin and myrrh obtained from the aloe-gum resin of Commiphora molmol on experimental trichinosis. Ninety albino mice were orally infected with 300 T. spiralis larvae. Drugs were tested against adult worms at day 0 and day 5 and against encysted larvae on day 15 and day 35 post-infection (PI). Mature worms and encysted larvae were counted in addition to histopathological examination of muscle specimens. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total protein, albumin, globulin, urea, and creatinine values were estimated. Significant reductions in mean worm numbers were detected in ivermectin treated mice at day 0 and day 5 PI achieving efficacies of 98.5% and 80.0%, while efficacies of myrrh in treated mice were 80.7% and 51.5%, respectively. At days 15 and 35 post-infection, ivermectin induced significant reduction in encysted larval counts achieving efficacies of 76.5% and 54.0%, respectively, while myrrh efficacies were 76.6% and 35.0%, respectively. AST, ALT, urea, and creatinine levels were reduced, while total proteins were increased in response to both treatments compared to their values in the infected non-treated mice. Ivermectin use for controlling T. spiralis could be continued. Myrrh was effective and could be a promising drug against the Egyptian strains of T. spiralis with results nearly comparable to ivermectin.
Animals ; Antiparasitic Agents/administration & dosage/*pharmacology ; Drug Therapy, Combination ; Ivermectin/administration & dosage/*pharmacology ; Mice ; Terpenes/administration & dosage/*pharmacology ; *Trichinella spiralis ; Trichinellosis/*drug therapy

Reptiles, unlike mammals, have been considered to be unsuitable hosts of Trichinella spp., though larvae have been detected in their muscles and human outbreaks related to their consumption have, in fact, occurred. Herein we report 2 Korean cases of trichinosis, possibly transmitted via consumption of reptile meat. Both patients suffered from myalgia, headache, and facial edema. Laboratory examinations revealed leukocytosis with eosinophilia (54% and 39%, respectively) and elevated creatinine phosphokinase. ELISA was performed under the suspicion of trichinosis, showing positivity at the 29th and 60th day post-infection. Since they had consumed raw soft-shelled turtle meat, turtle was strongly suggested to be an infection source of trichinosis in Korea next to the wild boar and badger.
Adult ; Animals ; Enzyme-Linked Immunosorbent Assay ; Foodborne Diseases/*diagnosis/parasitology/*pathology ; Humans ; Korea ; Male ; Meat ; Serologic Tests ; Trichinella/*isolation & purification ; Trichinellosis/*diagnosis/parasitology/*pathology ; Turtles

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.
Adult ; Animals ; Cause of Death ; China/epidemiology* ; Female ; Food Contamination ; Forensic Pathology ; Heart Failure/etiology* ; Humans ; Male ; Meat/parasitology* ; Middle Aged ; Muscle, Skeletal/pathology* ; Myocarditis/pathology* ; Myocardium/pathology* ; Swine ; Trichinellosis/pathology* ; Young Adult