No abstract

Genital infection by Chlamydia trachomatis is the most common bacterial sexually transmitted disease worldwide. It causes serious reproductive health complications, including pelvic inflammatory disease and infertility. Stress is implicated as a risk factor for various infections; however, its effect on chlamydia genital infection is unknown. We previously showed that repeated exposure of mice to cold water results in increased severity of chlamydia genital infection. In this study, cold water-induced stress resulted in (i) elevated levels of norepinephrine (NE) and epinephrine in the spleen and genital tract of stressed mice; (ii) elevated IL-1β, TNF-α, IL-6 and nitric oxide production in macrophage-rich peritoneal cells of mice; (iii) supplement of NE in vitro exerts an immunosuppressive effect on splenic T-cell production of cytokines; (iv) decreased C. muridarum shedding in the genital tract of β1Adr/β2Adr receptor KO mice; and (v) a higher rate of infertility in infected mice. These results suggest that cold water stress induces the production of catecholamines, which may play a critical role in the modulation of the immune system leading to increased intensity of C. muridarum genital infection.

In recirculation finfish facilities in the United States and Canada, biosecurity utilization is neither consistent nor uniform. Seeking reasons for this situation, we examined the beliefs, perceptions, and attitudes of managers and owners of such facilities about fish disease and biosecurity utilization. A questionnaire was mailed in the fall of 2001 to the managers and owners of 152 finfish-rearing recirculation facilities in the United States and Canada to gather information on their attitudes, beliefs, and perceptions regarding fish disease and biosecurity. The response rate to the survey was 86%. This paper reports on a subset of the overall responses, the responses of managers and owners who identified their facility as a business operation. Although respondents had a positive attitude towards biosecurity utilization, they had different beliefs about which disease types were of greatest concern for their farm. Respondents also had differing perceptions on the risk of disease transmission associated with different activities on their farms. In addition, respondents had various beliefs about the practicality and effectiveness of different biosecurity measures and why the practice of biosecurity was important to their farms. This study gives quantitative evidence that different fish farmers perceive disease and the practice of biosecurity differently. This study indicates that recognition of the human dimensions element is an important first step in the creation of biosecurity policies, strategies, and procedures that will be readily accepted and implemented and consistently applied by fish farmers on their farms. The findings challenge the heretofore traditionally accepted belief that poor biosecurity practice on a farm is primarily related to lack of knowledge about biosecurity.

A cold-induced stress mouse model for investigating chlamydia genital infection and immune response analysis was established in our laboratory. Previous results showed that cold-induced stress results in suppression of the immune response and increased intensity of chlamydia genital infection in the mouse model. The purpose of the present study was to evaluate the potential therapeutic value of active hexose correlated compound (AHCC) against chlamydia genital infection in mice. AHCC is an extract of mushroom commonly used as a dietary supplement is known to boost the immune system. Mice were infected intravaginally with Chlamydia trachomatis after a 24-day cold-stress application. Oral administration of AHCC to stressed or non-stressed mice was carried out seven days before infection and during the course of infection along with cervicovaginal swabbing. Cytokine production by peritoneal and splenic T cells isolated from AHCC-fed stressed mice and non-stressed mice was measured ELISA. Splenic T cells from both animal groups were co-cultured with mouse monocyte J774.2 cell line or cultured by addition of supernatants of AHCC-treated J774.2 cell line for 24 hours. Infection studies showed that AHCC-feeding compared to phosphate buffered saline (PBS)-feeding to stressed mice resulted in reduced Chlamydia trachomatis shedding from the genital tract. Levels of tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) were significantly increased in stressed mice receiving AHCC compared to stressed mice receiving PBS. Production of interferon gamma (IFN-γ) and interleukin 2 (IL-2) in the AHCC group was significantly high compared to production in PBS-fed group. Splenic T cells from stressed and non-stressed cultured with supernatants of AHCC-treated J774.2 cell line resulted in significantly increased TNF-α or IFN-γ production. Results obtained in this study show that AHCC improves the function of immune cells as indicated by the restoration of levels of cytokines production that were suppressed under cold induced-stress conditions. This is the first report showing that oral administration of AHCC enhances the function of the immune system, which could result in increased resistance of the host to chlamydia genital infection.This is an open