Trichinella spiralis infection is mediated by MCP-1 and MIP-2, while echinococcus granulosus is strongly mediated by MCP-1, but not MIP-2

Increased neutrophil derived chemokines (CXCL10 and CCL2) in human trichinellosis as possible serological markers of the polarization of the immune response against the parasite

Trichinella britovi is a widely distributed parasitic nematode, transmitted through ingestion of raw or poorly cooked meat containing muscle larvae. This helminth can regulate the host immune system during the early phase of infection. The immune mechanism mainly involves the interaction of Th1 and Th2 responses and related cytokines. Chemokines (C-X-C or C-C) and matrix metalloproteinases (MMPs) have also shown to be implicated in a number of parasitic infections, mainly malaria, neurocysticercosis, angiostronyloidosis, and schistosomiasis, but poor is known about their role in human Trichinella infection. We previously found that serum MMP-9 levels were significantly increased in T. britovi infected patients with relevant symptoms such as diarrhea, myalgia, and facial oedema, which makes these enzymes a potential reliable indicator of inflammation in trichinellosis patients. These changes were also observed in T. spiralis/T. pseudospiralis experimentally infected mice. No data are available about circulating levels of two pro-inflammatory chemokines, CXCL10 and CCL2, in trichinellosis patients with or w/o clinical signs of the infection. In this study, the association of serum level of CXCL10 and CCL2 with clinical outcome of T. britovi infection and their relation to MMP-9 were investigated. Patients (median age 49 ± 0.33 years) acquired infection by consuming raw sausages prepared with wild boar and pork meat. Sera were collected during the acute and the convalescent phases of the infection. A positive significant association (r = 0.61, p = 0.0004) was observed between MMP-9 and CXCL10 levels. The CXCL10 level significantly correlated with the severity of symptoms in patients being particularly higher in patients suffering diarrhea, myalgia, and facial oedema, thus suggesting a positive association of this chemokine with symptomatologic traits, especially myalgia (and increased LDH and CPK levels) (p < 0.005). No correlation was found between levels of CCL2 and the clinical symptoms.

Inhibition of MCP-1 and MIP-2 Chemokines in Murine Trichinellosis: Effect of the Anti-Inflammatory Compound L-Mimosine

Mimosine, is a plant amino-acid which has been reported to block DNA replication in mammalian cells and to arrest cells reversibly towards the end of the G1 phase or at the beginning of the S phase. In this study, 42 mice were infected with T. spiralis, a nematode parasite, and treated with the anti-inflammatory compound L-mimosine, to determine if any alteration in the chronic inflammatory state occurred, by investigating the host's immunological response. MCP-1, a C-C chemokine and MIP-2, a C-X-C chemokine were tested and measured in the sera of infected animals, after 1, 10, 20, 30, 40, 50 and 60 days postinfection, by ELISA method. The diaphragm/muscle and the masseters of the infected mice, were tested for inflammatory response. We found that MCP-1 was partially inhibited by L-mimosine, while MIP-2 was totally inhibited. Moreover, in sections of the diaphragm and masseters, the infiltration of inflammatory cells such as macrophages, lymphocytes and eosinophils were more intense in untreated animals compared to those treated with L-mimosine. These findings show, that L-mimosine may have an inhibitory effect on MCP-1 and MIP-2 serum levels in Trichinellosis and may influence the recruitment of inflammatory cells and the intensity of the inflammatory reaction in this parasitic disease.

Cross-Sectional Serosurvey and Risk Factors Associated with the Presence of Toxoplasma gondii Antibodies in Pigs in Greece

INTRODUCTION

Toxoplasmosis is a worldwide reported zoonotic infection caused by the protozoon Toxoplasma gondii. Pigs may become infected by ingesting feed or water contaminated with cat faeces, by cannibalism, and/or by eating infected rodents. T. gondii infected edible tissues of pigs are a source of infection for humans. This study was undertaken to detect seropositivity of pigs against T. gondii and identify possible risk factors as well as to compare two serological methods.

METHODS

A total of 609 blood samples were collected from 10% of the sows from 65 pig farms located in mainland Greece. Information about the geographical location, size, and biosecurity level of the herd was recorded. Samples were tested for the presence of antibodies against T. gondii employing the indirect fluorescent antibody test and the enzyme-linked immunosorbent assay.

RESULTS

Twenty-six positive samples were detected (4.3%) in 17 out of the 65 farms tested (26.2%). The average seroprevalence in affected herds was 26.8% (95% confidence interval 21.0-32.6%). Among the categorical data evaluated, the biosecurity level (odds ratio 0.17, p < 0.01) and the geographical characteristics (odds ratio 13.55, p < 0.05) significantly affected the presence of toxoplasmosis in the herd. Toxoplasmosis was recorded in significantly higher percentages in mountainous farms as compared to lowlands (p < 0.05) and in those with poor biosecurity levels than in those with very good (p < 0.05). A very good agreement (κ = 0.958) was observed between the two serological methods.

CONCLUSION

The presence of antibodies in pigs is indirect information on the risk of the infection and an indication of the necessity of biosecurity measures to be taken in order to control infection at least in the areas at highest risk.

Novel Diagnostic Approaches to Adamantiades-Behcet's Disease

A 10 year old boy had visual deterioration in both eyes. Visual acuity was 0.2 in the right and 0.3 in the left eye. Further ophthalmologic findings were typical of posterior uveitis. The pediatric physical examination also disclosed aphthous stomatitis and recurrent aphthous genital ulcers. At diagnosis serum levels of IL-1β, IL-6, IL-8, TNF-α, sIL-2R, MCP-1, VEGF, tADA activity in the patient with active and ABD relapse were significantly higher than those in the inactive period of the disease, suggesting that these parameters may be related to disease activity. In addition to the proinflammatory chemokines and cytokines, plasma levels of VEGF and serum tADA activity may be used for the diagnosis of ABD and for monitoring the effect of treatment, as well as the follow-up period. Also, further studies of VEGF may lead to novel therapies with antibodies or other VEGF inhibitors.

The expression of LEC/CCL16, a powerful inflammatory chemokine, is upregulated in ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disease of unknown aetiology and pathogenesis. The presence in the colonic mucosa of reactive cells expressing proinflammatory cytokines and chemokines is associated with high levels of IL-10, an anti-inflammatory cytokine. Our aim was to investigate the role of IL-10 and the beta chemokine LEC/CCL16 selectively up-regulated by IL-10 in inflammatory cell recruitment and cytokine and chemokine production during UC. We studied histologically, immunohistochemically and ultrastructurally colonic biopsies from 20 active UC patients and 10 control specimens taken far from any macroscopically detectable lesion in age and sex-matched patients with noninflammatory bowel disease. In active UC, immature dendritic cells (DCs) in the LP are associated with IL-10 in the T cell rich area. Furthermore, most of the LP-infiltrating macrophages strongly expressed LEC/CCL16, a chemokine upregulated by IL-10. To evaluate if LEC/CCL16 plays a role in the inflammatory reaction present in UC, we performed morphological studies in mice injected s.c. with syngeneic tumor cells engineered to produce LEC/CCL16. We found that the LEC protein locally released by LEC-gene-transfected tumor cells is a potent proinflammatory chemokine that induces the recruitment of a reactive infiltrate, and an angiogenic process mirroring that in human UC.

Chemokines and Their Role in Parasitic Diseases

Chemotactic cytokines (chemokines), the intercellular mediators, produced and released by a wide variety of cell types, are a group of small secreted proteins (8–10 KDa), which mediate host response to invading organisms (viruses, bacteria, parasites), trauma or tumor. The trafficking, recruiting and recirculation of leukocytes, which is essential in acute and chronic inflammation is controlled by chemokines. This review introduces the three supergene families of chemokines (CXC, CC and C), with emphasis on their adhesion mechanism, biological effects, regulation of expression and critical role in different disease states in humans and in animal models with parasitic diseases.

Absence of CC chemokine ligand 2 results in an altered Th1/Th2 cytokine balance and failure to expel Trichuris muris infection

Despite a growing understanding of the role of cytokines in immunity to intestinal helminth infections, the importance of chemokines has been neglected. As a chemokine with both chemoattractive properties and an ability to shape the quality of the adaptive immune response, CC chemokine ligand 2 (CCL2) was investigated as an attractive candidate for controlling resistance to these types of infection, which require highly polarized Th cell responses. We show here for the first time that CCL2 plays an important role in the development of resistance to infection by the gastrointestinal nematode Trichuris muris. Thus, in the absence of CCL2, worm expulsion does not occur, and the lymph node draining the site of infection becomes a Th1-promoting environment. Elevated levels of IL-12 are produced by polarizing APCs, and the composition of the APC environment itself is perturbed, with reduced numbers of macrophages.

Some aspects of Parasitology and Immunology in general Medicine

The objective of these studies is to review the role of some parasites and their components in inflammation, allergy and immune system. We also report recent results published by others group as well as our own.

Prevalence of IgG antibodies against Borrelia Burgdorferi s.l. and Ehrlichia Phagocytophila in sera of patients presenting symptoms of Lyme disease in a central region of Italy

The aim of this study was to evaluate the prevalence (seroprevalence) of antibodies against Borrelia burgdorferi and Ehrlichia phagocytophila among patients resident in Lazio, a region of central Italy. Of a sample of 1,050 patients, which presented clinical manifestations related to Lyme disease, 34 (3.2%) were Borrelia-seropositive (Lyme index value >/= 1.2). The sera of 25 out of the 34 patients that were Borrelia-positive were also analysed for the presence of antibodies against E. phagocytophila and 3 (12%) were found Ehrlichia-positive (titres >1:64). No Ehrlichia positive samples were found among sera of 250 Borrelia-negative patients. Since both B. burgdorferi s.l. and Ehrlichia species share the same tick vector (Ixodes ricinus), our results indicate that concurrent transmission of these microbial pathogens might have been occurred among the patients included in this study.

MCP-1 and MIP-2 response in Trichinella spiralis infected mice treated with 4-deoxypyridoxine (4-DPD)

Chemokines are involved in a number of pathophysiological conditions, such as inflammatory processes and are divided in two major subfamilies, C-X-C and C-C chemokines. The C-C chemokines are monocyte chemotactic protein 1-2-3-4-5, while C-X-C chemokines include MIP-2, IL-8, etc. We studied the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue and serum in Trichinella spiralis infected mice treated and not treated with 4-deoxypyridoxine, a potent Vit. B6 antagonist which inhibits humoral and cellular immune response. MCP-1 and MIP-2 were measured in homogenized tissue and serum and determined by a specific ELISA. Here we found the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue of T. spiralis infected mice were significantly increased after 10 days and peaked on day 20 post-infection; however, the levels of MIP-2 in mice treated with 4-DPD was lower than that of untreated mice at day 20. MCP-1 also peaked at days 20 and 40. Animals treated with 4-DPD also inhibited the production of MCP-1, compared with untreated animals. The maximum inhibition was at day 40. These inhibitory effects on MIP-2 and MCP-1 were also repeated in the serum determinations, but were not significant. This study demonstrates that MIP-2 and MCP-1 are stimulated in serum and tissue of T. spiralis infected mice and 4-DPD-treated animals significantly inhibited them.

A spectrum of antibody (IgG. IgG1, IgM) response in mice infected with trichinella spiralis treated with L-mimosine

The purpose of this study was to demonstrate the anti-inflammatory effects of L-mimosine on chronic inflammation, by investigating its effect on the immunological response of BALB/c mice infected with the nematode parasite Trichinella spiralis. Specific anti-parasite immunoglobulins (IgG, IgG1 and IgM) were detected by the ELISA method in the serum of both the treated and the untreated animals at different periods of time for 60 days post infection. Two groups consisting of 18 mice each were used. The mice were 6 weeks of age. Both groups were infected with 220 larvae (L1-T. spiralis) per os: one group was administered an intraperitoneal injection of L-mimosine (200 &mgr;g/100 ml/dose) for 27 days (the first injection started 7 days before infection) and the second group was administered an intraperitoneal injection of saline solution (100 &mgr;l/dose). Parasite specific IgG, IgG1 and IgM levels were determined in the sera of infected, untreated mice. The levels of IgG and IgG1 were increased following infection and remained elevated throughout the experimental period, while IgM was significantly decreased on the 50th day post-infection. These levels were found to be lower in the L-mimosine treated infected mice, compared to the untreated mice. The inhibition started from day 10 and continued until day 60. In healthy animals, the production of immunoglobulins was not measurable. Non-infected animals treated with L-mimosine also showed no detectable anti-parasite specific immunoglobulins.

Inhibition of MCP-1 and MIP-2 transcription and translation by mimosine in muscle tissue infected with the parasite Trichinella spiralis

Mimosine is a non-toxic plant aminoacid which is an effective inhibitor of DNA replication by acting at the S-phase. In this study we infected mice with T. spiralis, a nematode parasite, and studied the inflammatory response through the determination of MIP-2, a C-X-C chemokine and MCP-1, a C-C chemokine in the inflamed area around the parasitic cyst. The animals were infected and their diaphragms were tested for inflammatory response. MCP-1 and MIP-2 was tested after 1, 10, 20, 30, and 40 days post inoculation, before and after mimosine treatment. The inflammatory index was calculated by counting the white blood cells around the nematode cysts, while expression of MIP-2 and MCP-1 was calculated by ELISA method and transcription by Northern blot and RT-PCR. Here we found that mimosine strongly inhibited the inflammatory index in the diaphragmatic tissue at 10, 20, 30 and 40 days post-treatment. In these experiments, mimosine had no effect on the number of cysts produced. In addition, we found that MCP-1 transcription and translation was completely inhibited by mimosine, while MIP-2 transcription and translation was partially inhibited at 30 and 40 days; yet it was totally inhibited after 10 and 20 days in encysted diaphragm tissue infected by T. spiralis. Our studies suggest that mimosine has an inhibitory effect through the inhibition of cytoplasmatic serine hydroxymethyltransferase altering the cell cycle of white blood cells. This study suggests for the first time the premise that mimosine acts as an anti-inflammatory compound.

Toxocarosis as zoonosis. A review of literature and the prevalence of Toxocara canis antibodies in 511 serum samples

A total of 511 serum samples from children aged between 6 months to 15 years old, with different clinical signs-living in the region of Northern Greece - were tested by ELISA (enzyme links immunosorbent assay) technique, for the detection of specific IgG and IgM antibodies against T. canis antigen. The reason IgM was detected was because IgM levels are elevated in the acute phase of toxocara infection, in spite of their notorious non-specificity. In this seroepidemiologic survey of children, a remarkably high percentage (12.5&#x0025;) reacted positively to this method. Sixteen (3.1&#x0025;) out of 511 sera showed IgG antibodies, 43 (8.4&#x0025;) showed IgM, while 5 (1&#x0025;) showed both IgG and IgM antibodies against T. canis E/S (excretory - secretory) antigen. Females were significantly more infected than males. Seropositivity rate was highest in children over the age of 10.