To determine alteration of immune responses during visceral larva migrans (VLM) caused by Toxascaris leonina at several time points, we experimentally infected mice with embryonated eggs of T. leonina and measured T-helper (Th) cell-related serial cytokine production after infection. At day 5 post infection (PI), most larvae were detected from the lungs, spleen, intestine, and muscle. Expression of thymic stromal lymphopoietin (TSLP) and CCL11 (eotaxin) showed a significant increase in most infected organs, except the intestine. However, expression of the CXCL1 (Gro-alpha) gene was most highly enhanced in the intestine at day 14 PI. Th1-related cytokine secretion of splenocytes showed increases at day 28 PI, and the level showed a decrease at day 42 PI. Th2-related cytokine secretion of splenocytes also showed an increase after infection; in particular, IL-5 level showed a significant increase at day 14 PI, and the level showed a decrease at day 28 PI. However, levels of Th17-related cytokines, IL-6 and IL-17A, showed gradual increases until day 42 PI. In conclusion, Th1, Th2, and Th17-related cytokine production might be important in immune responses against T. leonina VLM in experimental mice.
Animals ; Brain/parasitology ; Cytokines/*metabolism ; Female ; Gene Expression Regulation ; Heart/parasitology ; Interleukins/*metabolism ; Intestines/parasitology ; Larva Migrans, Visceral/*immunology/parasitology ; Liver/parasitology ; Lung/parasitology/pathology ; Mice ; Mice, Inbred C57BL ; Muscles/parasitology ; Spleen/parasitology ; Th1 Cells/immunology ; Th17 Cells/immunology ; Th2 Cells/immunology ; Toxascaris/*immunology

BACKGROUND/AIMS: Visceral larva migrans, caused by Toxocara canis and Toxocara cati, has emerged as a significant cause of eosinophilic liver abscess (ELA). Differentiation of ELA associated with toxocariasis (ELA-T) from metastasis or primary liver malignancy is sometimes difficult. However, the role of albendazole treatment remains uncertain in this condition. The aim of this study was to evaluate whether albendazole can enhance the radiologic resolution of ELA-T. METHODS: We retrospectively reviewed the medical records of the patients diagnosed with ELA-T at our institution between January 2008 and December 2011. ELA-T was diagnosed based on the imaging findings on computed tomography or magnetic resonance imaging and the presence of positive serum IgG antibody for Toxocara canis. Among a total of 163 patients, 32 patients received albendazole (albendazole group) and 131 did not (control group). Baseline characteristics and fate of liver nodules were compared between the two groups. RESULTS: Baseline characteristics (age, sex, number and maximal size of lesions, eosinophil count) were similar between the two groups. Median duration for achieving radiologic resolution in the albendazole group was significantly shorter than in the control group (207 days [range 186-228] vs. 302 days [range 224-380], p=0.023). In Cox regression analysis of the cumulative rates of radiologic resolution, the hazard ratio for albendazole treatment was 1.99 (95% confidence interval, 1.22-3.23). CONCLUSIONS: Radiologic resolution of ELA-T can be accelerated with albendazole treatment. Hence, inconvenience associated with long-term follow-up and unnecessary worries among patients can be eliminated with albendazole treatment.
Adult ; Aged ; Aged, 80 and over ; Albendazole/*therapeutic use ; Animals ; Antiprotozoal Agents/*therapeutic use ; Eosinophils/*immunology ; Female ; Humans ; Immunoglobulin G/blood ; Larva Migrans, Visceral/*drug therapy/parasitology ; Liver/enzymology/metabolism ; Liver Abscess/*etiology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Proportional Hazards Models ; Retrospective Studies ; Tomography, X-Ray Computed ; Toxocara canis/immunology/isolation & purification