Activation of Fas/FasL pathway and the role of c-FLIP in primary culture of human cholangiocarcinoma cells

Intrahepatic cholangiocarcinoma (iCCA) represents a heterogeneous group of malignancies emerging from the biliary tree, often in the context of chronic bile ducts inflammation. The immunological features of iCCA cells and their capability to control the lymphocytes response have not yet been investigated. The aims of the present study were to evaluate the interaction between iCCA cells and human peripheral blood mononuclear cells (PBMCs) and the role of Fas/FasL in modulating T-cells and NK-cells response after direct co-culture. iCCA cells express high levels of Fas and FasL that increase after co-culture with PBMCs inducing apoptosis in CD4(+), CD8(+) T-cells and in CD56(+) NK-cells. In vitro, c-FLIP is expressed in iCCA cells and the co-culture with PBMCs induces an increase of c-FLIP in both iCCA cells and biliary tree stem cells. This c-FLIP increase does not trigger the caspase cascade, thus hindering apoptotis of iCCA cells which, instead, underwent proliferation. The increased expression of Fas, FasL and c-FLIP is confirmed in situ, in human CCA and in primary sclerosing cholangitis. In conclusion our data indicated that iCCA cells have immune-modulatory properties by which they induce apoptosis of T and NK cells, via Fas/FasL pathway, and escape inflammatory response by up-regulating c-FLIP system

Biliary tree stem/progenitor cells and perspectives in physiopathology and regenerative medicine

We have recently demonstrated the presence of cells expressing a constellation of endodermal markers in (peri)-biliary glands of extrahepatic bile ducts. These observations in situ in human tissues have been achieved by the in vitro demonstration that a subpopulation of cells [Pdx1+ (pancreatic and duodenal homeobox 1+)⁄Sox17+⁄EpCAM+ (epithelial cell adhesion molecule+)] isolated from the biliary epithelium have long-term (in vitro) persistence and self-renewal, and are able to give rise to a more restricted progeny towards different mature lineages (hepatocytes, cholangiocytes and β-pancreatic cells). The discovery of these cells, named human biliary tree stem/progenitor cells, opens a new scenario impacting many different aspects of hepato-gastroenterology including embryology of liver, biliary epithelium and pancreas, biliary pathophysiology, he

BIOTIMER ASSAY FOR COUNTING BACTERIAL BIOFILM

A growing body of evidences shows that bacterial biofilm lifestyle is comparatively more common than the planktonic one and that biofilm plays a crucial role in human health. The enumeration of the actual number of bacteria in biofilm is still a great challenge for microbiologist. The standardized method of colony forming unit (CFU) count is not reliable to quantify bacteria in biofilm. In the absence of a validated method to count bacteria in biofilm, BioTimer Assay (BTA) is presented here. BTA allows to count bacterial biofilm adherent on surfaces and employs an appropriate reagent containing an indicator able to switch as a consequence of bacterial metabolism in biofilm. The time required for indicator switch, induced by microbial metabolism, is correlated to the initial number of bacteria (N0) through a genus-specific correlation line described by the following equation t = log(1+a=N0)=k where k is growth rate and a is a function of the metabolic product responsible for the reagent switching. Moreover, BTA does not require any manipulation of samples and has been applied to count bacteria in biofilm adherent to several polymers, to verify microbiological quality of foods and to detect the antibiotic susceptibility of biofilm. BTA, providing a reliable, sensitive, rapid and easy-to perform method, could be considered a useful tool in counting bacteria in biofilm also adherent on nano-structured particles to be in vivo administered

Biotimer assay for counting bacterial biofilm

A growing body of evidences shows that bacterial biofilm lifestyle is comparatively more common than the planktonic one and that biofilm plays a crucial role in human health. The enumeration of the actual number of bacteria in biofilm is still a great challenge for microbiologist. The standardized method of colony forming unit (CFU) count is not reliable to quantify bacteria in biofilm. In the absence of a validated method to count bacteria in biofilm, BioTimer Assay (BTA) is presented here. BTA allows to count bacterial biofilm adherent on surfaces and employs an appropriate reagent containing an indicator able to switch as a consequence of bacterial metabolism in biofilm. The time required for indicator switch, induced by microbial metabolism, is correlated to the initial number of bacteria (N0) through a genus-specific correlation line described by the following equation t = log(1+a=N0)=k where k is growth rate and a is a function of the metabolic product responsible for the reagent switching. Moreover, BTA does not require any manipulation of samples and has been applied to count bacteria in biofilm adherent to several polymers, to verify microbiological quality of foods and to detect the antibiotic susceptibility of biofilm. BTA, providing a reliable, sensitive, rapid and easy-to perform method, could be considered a useful tool in counting bacteria in biofilm also adherent on nano-structured particles to be in vivo administere

Biotimer assay for counting bacterial biofilm

A growing body of evidences shows that bacterial biofilm lifestyle is comparatively more common than the planktonic one and that biofilm plays a crucial role in human health. The enumeration of the actual number of bacteria in biofilm is still a great challenge for microbiologist. The standardized method of colony forming unit (CFU) count is not reliable to quantify bacteria in biofilm. In the absence of a validated method to count bacteria in biofilm, BioTimer Assay (BTA) is presented here. BTA allows to count bacterial biofilm adherent on surfaces and employs an appropriate reagent containing an indicator able to switch as a consequence of bacterial metabolism in biofilm. The time required for indicator switch, induced by microbial metabolism, is correlated to the initial number of bacteria (N0) through a genus-specific correlation line described by the following equation t = log(1+a=N0)=k where k is growth rate and a is a function of the metabolic product responsible for the reagent switching. Moreover, BTA does not require any manipulation of samples and has been applied to count bacteria in biofilm adherent to several polymers, to verify microbiological quality of foods and to detect the antibiotic susceptibility of biofilm. BTA, providing a reliable, sensitive, rapid and easy-to perform method, could be considered a useful tool in counting bacteria in biofilm also adherent on nano-structured particles to be in vivo administere