Intestinal P glycoprotein acts as a natural defense mechanism against Listeria monocytogenes.
نویسندگان
چکیده
Mechanisms by which the intestinal epithelium resists invasion by food-borne pathogens such as Listeria monocytogenes are an evolving area of research. Intestinal P glycoprotein is well known to limit the absorption of xenobiotics and is believed to act as a cytotoxic defense mechanism. The aim of this study was to determine if intestinal P glycoprotein is involved in host defense against L. monocytogenes. Caco-2 cells and a P-glycoprotein-overexpressing subclone (Caco-2/MDR) were employed in addition to mdr1a(-/-) mice and wild-type controls. In vitro invasion assays and in vivo experiments were employed to measure bacterial invasion and dissemination. In addition, L. monocytogenes proteins were labeled with [(35)S]methionine, and the transepithelial transport across Caco-2 monolayers was characterized in both directions. Overexpression of P glycoprotein in Caco-2/MDR cells led to increased resistance to L. monocytogenes invasion, whereas P-glycoprotein inhibition led to increased invasion. Flux of [(35)S]methionine-labeled L. monocytogenes proteins was significantly greater in the basolateral-to-apical direction than in the apical-to-basolateral direction, indicating dependence on an apically located efflux transporter. Moreover, inhibiting P glycoprotein reduced the basolateral-to-apical flux of the proteins. Early dissemination of L. monocytogenes from the gastrointestinal tract was significantly greater in the mdr1a(-/-) mice than in wild-type controls. Expression and function of intestinal P glycoprotein is an important determinant in resistance to early invasion of L. monocytogenes.
منابع مشابه
Multifaceted Defense against Listeria monocytogenes in the Gastro-Intestinal Lumen
Listeria monocytogenes is a foodborne pathogen that can cause febrile gastroenteritis in healthy subjects and systemic infections in immunocompromised individuals. Despite the high prevalence of L. monocytogenes in the environment and frequent contamination of uncooked meat and poultry products, infections with this pathogen are relatively uncommon, suggesting that protective defenses in the ge...
متن کاملCommensal microbes provide first line defense against Listeria monocytogenes infection
Listeria monocytogenes is a foodborne pathogen that causes septicemia, meningitis and chorioamnionitis and is associated with high mortality. Immunocompetent humans and animals, however, can tolerate high doses of L. monocytogenes without developing systemic disease. The intestinal microbiota provides colonization resistance against many orally acquired pathogens, and antibiotic-mediated deplet...
متن کاملMyD88-mediated signals induce the bactericidal lectin RegIIIγ and protect mice against intestinal Listeria monocytogenes infection
Listeria monocytogenes is a food-borne bacterial pathogen that causes systemic infection by traversing the intestinal mucosa. Although MyD88-mediated signals are essential for defense against systemic L. monocytogenes infection, the role of Toll-like receptor and MyD88 signaling in intestinal immunity against this pathogen has not been defined. We show that clearance of L. monocytogenes from th...
متن کاملProduction of bacteriocin by a novel Bacillus sp. strain RF 140, an intestinal bacterium of Caspian Frisian Roach (Rutilus frisii kutum)
Bacteriocins are proteinaceous antibacterial compounds that exhibit bactericidal activity against species closely related to the producer strain. The aim of this research was to investigate the production of bacteriocin by Bacillus spp. isolated from intestinal bacterial flora of the Caspian Frisian Roach (Rutilus frisii kutum). A bacteriocin produced by the bacterium Bacillus cereus strain RF ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Infection and immunity
دوره 72 7 شماره
صفحات -
تاریخ انتشار 2004