Clonorchis sinensis infection is positively associated with atopy in endemic area.

BACKGROUND: Epidemiologic studies have suggested that helminth infections play a protective role against allergy; this inverse association, however, has not been consistent. Clonorchis sinensis, the liver fluke of human, is prevalent in the Far East. The association between C. sinensis infection and allergy has not yet been reported. OBJECTIVE: We evaluated the association between clonorchiasis and atopy or allergic diseases in adults in endemic areas of clonorchiasis. METHODS: A total of 1116 subjects (males 419, females 697; age range, 30-86; mean age=61 years) were recruited from two endemic areas of C. sinensis in Korea. Clonorchiasis was confirmed by stool examination. Allergic symptoms were evaluated with a modified ISAAC questionnaire, and atopy was defined by skin prick test for common inhalant allergens. Total serum IgE and C. sinensis-specific IgE level was measured by ELISA and methacholine bronchial provocation test was performed to evaluate airway hyperresponsiveness (AHR). RESULTS: Clonorchiasis was positively associated with atopy [odds ratio (OR), 1.856; 95% confidence interval (CI), 1.199-2.873] and high levels of total serum IgE (OR, 1.455; 95% CI, 1.050-2.016). Higher association with clonorchiasis was shown in subjects who showed both atopy and high total serum IgE levels (OR, 2.540; 95% CI, 1.448-4.455). Clonorchiasis had no association with wheezing, AHR, asthma or allergic rhinitis. CONCLUSION AND CLINICAL RELEVANCE: Clonorchiasis was positively associated with atopy in adults in endemic area.

Injury to the blood-testis barrier after low-dose-rate chronic radiation exposure in mice.

Exposure to ionising radiation induces male infertility, accompanied by increasing permeability of the blood-testis barrier. However, the effect on male fertility by low-dose-rate chronic radiation has not been investigated. In this study, the effects of low-dose-rate chronic radiation on male mice were investigated by measuring the levels of tight-junction-associated proteins (ZO-1 and occludin-1), Niemann-Pick disease type 2 protein (NPC-2) and antisperm antibody (AsAb) in serum. BALB/c mice were exposed to low-dose-rate radiation (3.49 mGy h(-1)) for total exposures of 0.02 (6 h), 0.17 (2 d) and 1.7 Gy (21 d). Based on histological examination, the diameter and epithelial depth of seminiferous tubules were significantly decreased in 1.7-Gy-irradiated mice. Compared with those of the non-irradiated group, 1.7-Gy-irradiated mice showed significantly decreased ZO-1, occludin-1 and NPC-2 protein levels, accompanied with increased serum AsAb levels. These results suggest potential blood-testis barrier injury and immune infertility in male mice exposed to low-dose-rate chronic radiation.

A novel form of self tolerance dictated in the thymus of transgenic mice with autoreactive TCR alpha and beta chain genes.

Transgenic (TG) mice with TCR alpha and beta chain genes from a CD4-dependent auto-I-Ak reactive T cell clone were generated. H-2k TG mice had a large number of thymic and splenic CD4 T cells expressing the autoreactive TCR without manifestation of autoimmunity. The cells were not anergic, as they could respond to autologous antigen presenting cells and anti-TCR antibodies in vitro to proliferate and to produce interleukins. Various degrees of down-regulation of CD2 and CD44 was observed in TG mice, indicating the presence of a defective co-stimulatory process in TG T cells. These features indicate that the self tolerance in autoreactive TCR TG mice is due not to clonal deletion and anergy but to a novel mechanism where T cells cannot sufficiently respond to normally existing self ligand in vivo. That such an in vivo unresponsiveness of autoreactive T cells is dictated in the thymus during CD4 T cell differentiation atypical form of positive selection of autoreactive T cells was suggested by the abnormal surface expression of CD69 and HSA.