Immunolocalization of intercellular adhesion molecule-1 and leukocyte functional associated antigen-1 in schistosomal soluble egg antigen-induced granulomatous hyporesponsiveness

Immunomodulatory effect of garlic oil extract on Schistosoma mansoni infected mice

OBJECTIVE

To assess the effect potency, and the immunomodulatory response of garlic oil extract in enhancing the host's immune system against the disorders caused by Schistosoma mansoni (S. mansoni) in mice at different stages of worm maturation.

METHODS

A total of 70 male CD-1 Swiss albino mice were divided into 7 groups. Group I: healthy control. Group II: garlic oil group orally administrating 100 mg garlic oil extract/kg b.wt. 3 d a week for 6 weeks. Group III: infected with S. mansoni cercariae and left untreated for 42 d. Group IV: treated with garlic oil extract from day 1 to day 7 post infection (PI). Group V: treated with garlic oil extract from day 14 till day 21 PI. Group VI: administrating garlic oil extract from day 35 until day 42 PI. Group VII received oil extract from the first day of infection for 42 d.

RESULTS

Garlic oil extract showed changes in the parasite tegument with a significant decrease in worm burden, hepatic and intestinal ova count with a decline in granuloma number and diameter. These alterations were accompanied with a reduction in serum TNF α, ICAM-1, IgG and IgM after 7 and 42 d post S. mansoni cercarial infection.

CONCLUSIONS

Results obtained confirmed the effect of garlic oil extract on the larval and mature stage of the parasite and in enhancing the host's immune system against the disorders caused by S. mansoni in mice.

sTNFR-II and sICAM-1 are associated with acute disease and hepatic inflammation in schistosomiasis japonica

Soluble intracellular adhesive molecule 1 (sICAM-1) and tumour necrosis factor receptors I (TNFR-1) and II (TNFR-II) have been shown to be associated with numerous liver disorders. Shedding of these membrane proteins can be triggered by the Th1 cytokines, TNF-alpha and IFN-gamma, which are associated with susceptibility or resistance to hepatic schistosomiasis, respectively. Further, TNF-alpha receptors and sICAM-1 have been implicated in periportal fibrosis in advanced human schistosomiasis mansoni and correlate with schistosome granuloma formation in the murine model. We measured serum levels of sICAM-1, TNFR-I and TNFR-II in Chinese patients with different clinically defined stages of schistosomiasis japonica and controls; these included 35 patients with acute schistosomiasis, 45 patients with chronic schistosome infections, 34 advanced patients with evidence of severe morbidity and 20 patients with no known history of exposure to infection. Markedly elevated levels of soluble TNFRs (sTNFRs) and sICAM-1 were observed in the acute and advanced patients compared with the chronic and control groups. Mean sTNFR-II levels were significantly higher in acute patients compared with advanced (P < 0.00001) and chronic patients (P < 0.00001) and showed the strongest association of the markers with acute disease (odds ratio (OR) = 1.099). sTNFR-II and sICAM-1 levels both correlated with infection intensity and there were significant positive correlations observed between eosinophil count and infection intensity (P = 0.0072) and sICAM-1 (P = 0.0014). Although there were significantly higher levels of antigen-specific IgG4 and total IgG in infected individuals compared with controls, none correlated with infection intensity. Further, no differences in IgG4 and total IgG levels were observed between the acute and chronic groups. The results suggest sTNFRs and sICAM-1 are associated with liver inflammation and disease progression. Measurement of sTNFR-II and sICAM-1 levels in serum could serve as additional markers for the diagnosis of acute stage disease and the monitoring of hepatic inflammation in human schistosomiasis japonica.

Experimental models of Schistosoma mansoni infection

Experimental models of Schistosoma mansoni infections in mammals have contributed greatly to our understanding of the pathology and pathogenesis of infection. We consider here hepatic and extrahepatic disease in models of acute and chronic infection. Experimental schistosome infections have also contributed more broadly to our understanding of granulomatous inflammation and our understanding of Th1 versus Th2 related inflammation and particularly to Th2-mediated fibrosis of the liver.