Oligoclonal expansions of CD4+ and CD8+ T-cells in the target organ of patients with biliary atresia
Oligoclonal expansions of CD4+ and CD8+ T-cells in the target organ of patients with biliary atresia. (PKO) and packed circles (WT) depict individual mice infected with RRV. (B) Serum ALT and (C) total bilirubin levels in saline and RRV-challenged WT and PKO MRS1477 mice at 5, 7 and 14 days after challenge; N=3-4 mice/group/ time-point; *=P 0.03. NIHMS535683-product-04.psd (1.7M) GUID:?7964C7DE-3A35-436E-9D7B-D77057D9D98A 05. Supplementary Fig. 3. Effect of FUT-175 on extended cholangiocyte cell lysis and end result after RRV contamination. (A) Mean SD percent 51Cr release in a lysis assay with hepatic NK cells from wild-type (WT) mice and cholangiocytes with or without FUT-175. Hepatic NK cells were obtained from a pool of 6C8 livers; *=P 0.01. (B) Daily injections of FUT-175 did not improve weight loss, jaundice or survival of wild-type (WT) mice challenged with RRV. (C) Longitudinal sections of MRS1477 extrahepatic bile ducts (stained with hematoxylin/eosin) from WT mice showing the normal anatomy after saline (top panel), common duct inflammation and obstruction after RRV (middle panel), and comparable duct injury of RRV-challenged mice despite treatment with FUT-175. NIHMS535683-product-05.psd (1.7M) GUID:?BF004290-94E1-4F9A-8135-97A9E34CAA22 06. Supplementary Fig. 4. Expression of cytotoxic effector genes in infants with biliary atresia. mRNA expression for in livers of infants with biliary atresia and control livers was quantified by real-time PCR and expressed as a ratio to human did not change, mRNA levels for and increased in diseased livers. mRNA, but not rotavirus (RRV)-induced biliary atresia, disruption of the adaptive immune response by loss of Ifn or CD8 T cells reduced bile duct obstruction and improved the cholestasis phenotype [9, 10]. Recently, we ascribed a key function for NK cells in the initiation of epithelial injury by engaging and lyzing cholangiocytes through the Nkg2d receptor . The effector mechanisms used by NK cells to target cholangiocytes, however, remain largely unknown. Innate immune lymphocytes are critical for early host defenses against viral infections and exert cytotoxic effects against virus-infected cells primarily by granule exocytosis . This potent cytolytic process is usually housed within the cytoplasmic granules rich in perforin, granzymes and other effector molecules. In addition, binding of stimulatory receptors like Nkg2d on cytotoxic cells by ligands of target cells activates a cascade of intracellular signaling events resulting in the secretion of Ifn and Tnf, and in the polarization and exocytosis of cytolytic granules [13, 14]. Chief among these granules are perforin and granzymes that work in concert to obvious virus-infected cells . Based on the central role of NK and CD8 T cell signaling in cholangiocyte injury and on the increased expression of perforin and granzymes in livers of patients MRS1477 with biliary atresia [10, 11], we hypothesized that this perforin-granzyme system is required for epithelial injury of bile ducts. Screening this hypothesis using complementary in vitro and animal methods, we found that the individual loss of perforin or inhibition of granzymes experienced minimal impact on the development of bile duct injury after RRV. However, the simultaneous loss/inhibition of both granules prevented cholangiocyte lysis and bile duct obstruction, and improved the phenotype of experimental MRS1477 biliary atresia. MATERIALS AND METHODS Experimental model of biliary atresia BALB/c mice were purchased from Charles River Laboratories (Wilmington, MA) and Balb/c knockout (PKO) mice were a kind gift from Dr. John T. Harty (University or college of Iowa, Iowa City, IA). Newborn PKO and WT mice were injected intraperitoneally with 1.5 106 fluorescence-forming units (ffu) of RRV in 20l volume within 24 hours of birth to induce experimental biliary atresia as explained previously . In granzyme blocking studies, the protease inhibitor nafamostat mesilate (FUT-175, Enzo Life Sciences, Inc., Farmingdale, NY) was administered intraperitoneally at a dose of 15g/g body weight in 20 l 1X phosphate buffered saline (PBS) soon after birth followed by RRV contamination 24 hours later; control mice received 20l MRS1477 of PBS [9-11]. Thereafter, FUT-175 was administered daily until 14 days of life. Groups of mice were sacrificed between 3C14 days and the extent of duct injury was decided . The Institutional Animal Care and Use Committee (IACUC) of the Cincinnati Children’s Research Foundation approved all the animal experiments and protocols. Human livers Liver RNA was isolated from 1C3 month aged infants at the time of diagnosis of biliary atresia. Control biopsies were obtained from livers of deceased donors aged 2C3.5 years being used for transplantation; age-matched donors Rabbit Polyclonal to ARHGEF11 from healthy subjects were not pursued due to ethical considerations. These subjects were described in a previous publication [3, 11]. Written informed consent was obtained from the patients guardians. Liver function assessments Serum total bilirubin (Total Bilirubin Reagent Set; Pointe Scientific, Inc. Canton, MI) and alanine transaminase.