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PubMedDate not supplied

Immune-signalling by orally-delivered probiotic bacteria: effects on common mucosal immunoresponses and protection at distal mucosal sites.

Probiotics--orally-delivered preparations of non-pathogenic bacterial cells--have been reported to increase anti-microbial protection in the gastrointestinal tract environment, and offer a safe and effective non-pharmaceutical means for combating infectious diseases and certain other pathologies. There is also an increasing body of evidence to suggest that immunostimulation by probiotic bacteria in the gut can enhance immune protection at distal mucosal sites, such as the urogenital and respiratory tracts. This review summarises the current information, from both clinical and animal model studies, of a role for orally-delivered probiotics in modulating mucosal immunoresponses and protection at distal sites. While it is clear that probiotics hold promise in this area, research that is targeted toward identifying the mechanism driving stimulation of the common mucosal immune system, as well as patterns of mucosal tissue homing by immunocytes following probiotic-mediated signalling in the gut, is strongly encouraged.

Administration, Oral↗

PubMedDate not supplied

Effect of field capture on the measurement of cellular immune responses in wild ferrets (Mustela furo), vectors of bovine tuberculosis in New Zealand.

Ferrets are recognised as significant wildlife vectors of bovine tuberculosis (Tb) in New Zealand. Disease management strategies, such as the development of a protective wildlife vaccine, could be assisted by the ability to measure pertinent cellular immune responses among wild animals. In the present study, we investigated whether it is possible to measure in vitro lymphocyte reactivity in wild-caught ferrets, and also determined levels of physiological stress in these animals, and we compared these responses to those observed in laboratory-maintained domesticated ferrets. Over a 12-month period, 80 ferrets were live-captured from a Tb-endemic region (Otago, southern New Zealand); cardiac blood was withdrawn on-site, and mononuclear cell cultures were successfully established from 75 of these animals. Lymphocyte transformation (LT) responses to T cell and T/B cell mitogens (Concanavalin A [Con A] and pokeweed mitogen) were measured via uridine incorporation assay. The magnitude of these responses did not differ significantly between animals that had been captured in wire-framed cage traps and those captured using soft-jawed leg-hold traps. Levels of serum cortisol and glucose (as indicators of physiological and oxidative stress, respectively) were highest in animals captured using leg-hold traps. In comparison to domesticated ferrets, wild-caught ferrets had lower overall LT responses to Con A, but significantly higher levels of serum cortisol. Finally, 10/80 animals captured from the wild were severely diseased (Tb+), as evidenced by gross tuberculous lesions at autopsy. Successful mononuclear cell cultures were established from nine of these animals; LT responses to Con A were significantly lower in Tb+ ferrets than in either wild-caught/non-diseased (Tb-) or domesticated ferrets. These results demonstrate that it is possible to measure cellular immune responses from the blood of wild-caught ferrets, but that field capture and disease status may have detrimental effects on in vitro T cell function, possibly due to the influence of physiological stress.

Animals↗