Effects of exposure to environmentally relevant concentrations of lead (Pb) on expression of stress and immune-related genes, and microRNAs in shorthorn sculpins (Myoxocephalus scorpius).

Old lead-zinc (Pb-Zn) mining sites in Greenland have increased the environmental concentration of Pb in local marine organisms, including the shorthorn sculpin. Organ metal concentrations and histopathology have been used in environmental monitoring programs to evaluate metal exposure and subsequent effects in shorthorn sculpins. So far, no study has reported the impact of heavy metals on gene expression involved in metal-related stress and immune responses in sculpins. The aim of this study was to investigate the effect of exposure to environmentally relevant waterborne Pb (0.73 ± 0.35 µg/L) on hepatic gene expression of metallothionein (mt), immunoglobulin M (igm), and microRNAs (miRNAs; mir132 and mir155) associated with immune responses in the shorthorn sculpin compared to a control group. The mt and igm expression were upregulated in the Pb-exposed group compared to the control group. The transcripts of mir132 and mir155 were not different in sculpins between the Pb-exposed and control group; however, miRNA levels were significantly correlated with Pb liver concentrations. Furthermore, there was a positive correlation between liver Pb concentrations and igm, and a positive relationship between igm and mir155. The results indicate that exposure to Pb similar to those concentrations reported in in marine waters around Greenland Pb-Zn mine sites influences the mt and immune responses in shorthorn sculpins. This is the first study to identify candidate molecular markers in the shorthorn sculpins exposed to waterborne environmentally relevant Pb suggesting mt and igm as potential molecular markers of exposure to be applied in future assessments of the marine environment near Arctic mining sites.

Primary Cell Lines From Feathers and Blood of Free-Living Tawny Owls (Strix aluco): A New In Vitro Tool for Non-Lethal Toxicological Studies.

The validation of the use of primary cell lines from non-lethal matrixes of feathers and blood of nestlings of a wild bird species, the tawny owl (Strix aluco) is described. Tawny Owl Feather Fibroblast (TOFF) cells and peripheral blood mononuclear cells (PBMCs) were isolated and cultured from the pulp of the secondary wing feathers and whole blood respectively from free-living tawny owl nestlings. Cell growth was registered up until 48 h for both the PBMC cells and the TOFFs. The validation of these primary cell lines in free-living birds has the potential to advance the assessment of immunotoxicological effects in wildlife via non-lethal manner. They provide a key tool with which to study cell toxicity and responses to environmental stressors on a cellular level in wild bird species of interest.

Systemic antibody response to Chlamydia Trachomatis infection in patients either infected or reinfected with different Chlamydia serovars.

INTRODUCTION: Chlamydia trachomatis is the etiological agent for the most prevalent bacterial sexually transmitted infection in both developed and developing countries. The aim of present study was to characterize the antibody response between two groups of individuals, having either a single C. trachomatis infection and or repeated infections. MATERIAL AND METHODS: Current study consisted of two groups, one with an initial Chlamydia infection and a second with repeated infections. A titre based estimation of specific serum (IgG and IgA) levels using ELISA were performed, which further validated by western blot. In vitro neutralizing ability of each patient's serum against both homologous and heterologous strains was also determined. RESULTS: Individuals infected with one of the C. trachomatis serovars D, E or K exhibited a strong systemic antibody response as characterized by ELISA and western blot. These individuals may have developed at least some level of protection as they only represented single infection. By comparison, individuals infected with serovar D, E or F that exhibited low systemic antibody response often presented repeated C. trachomatis infections, suggesting an association with poor immune response. An in vitro neutralizing level of 60-90% was observed in the human sera against homologous serovar D and two heterologous C. trachomatis serovars E and K, compared to <40% against heterologous serovars F. CONCLUSION: Individuals infected with serovars D and K showed a potential association between circulating antibody response and re-infection risk. While the patients infected with serovars E showed a disconnection between systemic antibody response and re-infection risk.