Related Experiment Videos
Evolution of the schistosomal hepatic lesions in mice after curative chemotherapy
Abstract:
Mice with 64-day-old Schistosoma mansoni infection (+/- 27 worms, 8-12 pairs) were treated simultaneously with oxamniquine and hycanthone. The cure rate was 100%, and changes occurring thereafter in the liver were sequentially followed by means of histologic, ultrastructural, and immunofluorescence methods. Soon after treatment, hepatitic changes cleared up and periovular granulomas diminished in size. The predominant Type III collagen in granulomas was reduced, and the Type I showed no apparent increase, whereas Type IV did not seem to participate in the process. Collagen fibrils in periovular granulomas changed in texture from dense and more oriented to loose and disorganized. Fibroblasts, at first with marked signs of hyperfunction, became less so at a time when collagen fragments appeared within secondary lysosomes in macrophages and fibroblasts. Schistosomal ovular antigens remained sequestered inside the fibrotic granulomas up to the final, 39th day after treatment. Thus, specific treatment of schistosomiasis showed a beneficial effect upon the hepatic lesions from the very beginning and promoted changes in the periovular granulomas that indicated a rapid, although incomplete, resorption of fibrosis.
Insights
This study shows that treating Schistosoma mansoni infection in mice with oxamniquine and hycanthone completely cured the infection and initiated rapid liver healing. Hepatic lesions and granulomas resolved, indicating effective fibrosis resorption.
Area of Science:
- Parasitology
- Hepatology
- Immunology
Background:
- Schistosoma mansoni infection causes significant liver pathology.
- Periovular granulomas and fibrosis are key features of hepatic schistosomiasis.
- Understanding the resolution of liver lesions post-treatment is crucial.
Purpose of the Study:
- To evaluate the effects of combined oxamniquine and hycanthone treatment on established Schistosoma mansoni liver infections in mice.
- To investigate the sequential histological, ultrastructural, and immunofluorescence changes in liver tissue after treatment.
Main Methods:
- Mice with chronic Schistosoma mansoni infection were treated with oxamniquine and hycanthone.
- Liver tissues were analyzed using histological, ultrastructural, and immunofluorescence techniques.
- Collagen types, fibroblast activity, and antigen sequestration were assessed.
Main Results:
- 100% cure rate was achieved with combined therapy.
- Hepatitic changes and periovular granulomas rapidly diminished post-treatment.
- Type III collagen decreased, collagen fibrils became disorganized, and fibroblast activity reduced.
- Schistosomal antigens remained sequestered within granulomas up to 39 days post-treatment.
Conclusions:
- Combined oxamniquine and hycanthone treatment is highly effective against Schistosoma mansoni.
- The treatment initiates rapid beneficial changes in hepatic lesions and promotes fibrosis resorption.
- While effective, the resolution of fibrosis and antigen clearance is incomplete within the study period.