Eosinophilic gastritis in adult complicated by gastric ulcer perforation.

Eosinophilic gastritis is a rare type of eosinophilic gastrointestinal diseases. Patients with eosinophilic gastritis usually present with symptoms such as nausea, emesis, abdominal pain, and weight loss. In severe cases, patients can suffer rare complications such as gastric outlet obstruction and spontaneous perforation. Here, we present the case of a young adult male who presented with acute onset abdominal pain for 1 day. The patient was found to have significant mural thickening of gastric antrum with pneumoperitoneum on abdominal CT scan, consistent with a perforated gastric ulcer. The patient underwent exploratory laparotomy and required modified graham patch repair. The diagnosis of eosinophilic gastritis was made based on the pathology review of intraoperative endoscopic biopsy specimens.

Dietary polyamines promote intestinal adaptation in an experimental model of short bowel syndrome.

Intestinal adaptation does not necessarily recover absorptive capacity in short bowel syndrome (SBS), sometimes resulting in intestinal failure-associated liver disease (IFALD). Additionally, its therapeutic options remain limited. Polyamines (spermidine and spermine) are known as one of the autophagy inducers and play important roles in promoting the weaning process; however, their impact on intestinal adaptation is unknown. The aim of this study was to investigate the impact of polyamines ingestion on adaptation and hepatic lipid metabolism in SBS. We performed resection of two-thirds of the small intestine in male Lewis rats as an SBS model. They were allocated into three groups and fed different polyamine content diets (0%, 0.01%, 0.1%) for 30 days. Polyamines were confirmed to distribute to remnant intestine, whole blood, and liver. Villous height and number of Ki-67-positive cells in the crypt area increased with the high polyamine diet. Polyamines increased secretory IgA and mucin content in feces, and enhanced tissue Claudin-3 expression. In contrast, polyamines augmented albumin synthesis, mitochondrial DNA copy number, and ATP storage in the liver. Moreover, polyamines promoted autophagy flux and activated AMP-activated protein kinase with suppression of lipogenic gene expression. Polyamines ingestion may provide a new therapeutic option for SBS with IFALD.

Effect of linearly polarized microwaves on nanomorphology of calcium carbonate mineralization using peptides.

Microwaves are used for diverse applications such as mobile phones, ovens, and therapy devices. However, there are few reports on the effects of microwaves on diseases other than cancer, and on physiological processes. Here, we focused on CaCO3 mineralization as a model of biomineralization and attempted to elucidate the effect of microwaves on CaCO3 mineralization using peptides. We conducted AFM, ζ potential, HPLC, ICP-AES, and relative permittivity measurements. Our findings show that microwaves alter the nanomorphology of the CaCO3 precipitate, from sphere-like particles to string-like structures. Furthermore, microwaves have little effect on the mineralization when the mineralization ability of a peptide is high, but a large effect when the precipitation ability is low. Our findings may be applicable to not only the treatment of teeth and bones but also the development of organic-inorganic nanobiomaterials. This methodology can be expanded to other molecular/atomic reactions under various microwave conditions to alter reaction activity parameters.

An unusual case of small bowel obstruction because of body packing.

Body packing is the internal concealment of illicit drugs for the purpose of transportation and evasion of law enforcement. It is associated with medical complications such as acute toxicity from ingested drug, bowel obstruction or perforation. It is rare to require surgical intervention with a small amount of ingested drug packet. Here, we present the case of a young adult male who presented with abdominal pain for 3 days. The patient admitted ingesting a condom filled with suboxone several years ago and denied recent ingestion. The patient was found to have small bowel obstruction with ingested foreign body being a transition point on CT scan, requiring exploratory laparotomy and small bowel resection.

Bladder perforation as a rare complication of urethra sounding with a blunt marking pen.

Urethral sounding is the insertion of an object or liquid into the urethra for sexual gratification. It is associated with a substantial risk of loss of the foreign body in the bladder, urethral strictures or infection. Bladder perforation is a rare complication of urethral sounding which is usually associated with a sharp object. Here, we present the case of a young adult female presenting with abdominal pain after practicing urethral sounding with a blunt marking pen. She was found to have an intraperitoneal bladder perforation, requiring exploratory laparotomy and bladder repair.

Laparoscopic and endoscopic cooperative surgery for leiomyosarcoma of the stomach: a case report with a review of the literature.

BACKGROUND: Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s. We report here a patient with leiomyosarcoma of the stomach treated by laparoscopic and endoscopic cooperative surgery (LECS). CASE PRESENTATION: A 59-year-old man was referred to our hospital for an early gastric cancer, which was initially treated by endoscopic submucosal dissection. Six months after his initial treatment, a follow-up esophagogastroduodenoscopy revealed a small polypoid lesion at the lesser curvature of the proximal stomach, which appeared to be a hyperplastic polyp. However, one and a half years later, the lesion grew and showed more irregular surface. Biopsy at the time revealed smooth muscle cell proliferation suggestive of leiomyoma. Three years later, the lesion grew even larger and biopsy showed pleomorphic spindle cells. Immunohistochemical study showed positive staining for alpha-smooth muscle actin and desmin, but negative for c-kit and CD34. Ki-67 labeling index was nearly 60%. Based on these findings, the diagnosis of leiomyosarcoma was established. The patient subsequently underwent a partial gastrectomy by LECS. The patient is currently in good condition without recurrence or metastasis at 12 months after surgery. CONCLUSIONS: Leiomyosarcoma of the stomach is extremely rare. This is the first report of leiomyosarcoma of the stomach treated by LECS. We could also follow its appearance change through endoscopic examination for 3 years.

Donor plasmacytoid dendritic cells modulate effector and regulatory T cell responses in mouse spontaneous liver transplant tolerance.

We assessed the role of donor liver non-conventional plasmacytoid dendritic cells (pDCs) in spontaneous liver transplant tolerance in a fully MHC-mismatched (C57BL/6 (H2b ) to C3H (H2k )) mouse model. Compared with spleen pDCs, liver pDCs expressed higher levels of DNAX-activating protein of 12 kDa and its co-receptor, triggering receptor expressed by myeloid cells 2, and higher ratios of programed death ligand-1 (PD-L1):costimulatory CD80/CD86 in the steady state and after Toll-like receptor 9 ligation. Moreover, liver pDCs potently suppressed allogeneic CD4+ and CD8+ T cell proliferative responses. Survival of pDC-depleted livers was much poorer (median survival time: 25 days) than that of either untreated donor livers or pDC-depleted syngeneic donor livers that survived indefinitely. Numbers of forkhead box p3 (FoxP3)+ regulatory T cells in grafts and mesenteric lymph nodes of mice given pDC-depleted allogeneic livers were reduced significantly compared with those in recipients of untreated livers. Graft-infiltrating CD8+ T cells with an exhausted phenotype (programed cell death protein 1+ , T cell immunoglobulin and mucin domain-containing protein 3+ ) were also reduced in recipients of pDC-depleted livers. PD1-PD-L1 pathway blockade reversed the reduction in exhausted T cells. These novel observations link immunoregulatory functions of liver interstitial pDCs, alloreactive T cell exhaustion, and spontaneous liver transplant tolerance.

Preoperative pulmonary function tests do not predict the development of pulmonary complications after elective major abdominal surgery: A prospective cohort study.

BACKGROUND: Data describing the association of preoperative pulmonary function testing (PFT) with postoperative pulmonary complications (PPC) are inconsistent. We conducted this prospective study to determine the ability of PFT to predict PPC. MATERIALS AND METHODS: Data were prospectively collected from 676 patients who underwent elective abdominal surgery (emergency and thoracic operations excluded). The primary outcome was the occurrence of PPC within 30 days. Patient and procedure-related factors were examined as risk factors. Multivariate logistic regression analysis was performed using risk factors identified with univariate analysis and area under the curve (AUC) analysis performed. RESULTS: PPC occurred in 29 patients (4.9%). History of smoking or abnormal physical examination were not significantly associated. Multivariate analysis identified age (p = 0.03), operative time (p = 0.02), blood transfusions (p = 0.002), and %VC (p = 0.001) as significant risk factors. AUC with a model including age, operative time, and blood transfusion was 0.83. The addition of %VC to these three variables increased the AUC to 0.89 (p = 0.1). CONCLUSIONS: Age, operative time, blood transfusion, and %VC are significantly associated with an increased risk of PPC. The addition of %VC to other risk factors did not significantly improve the ability to predict PPC, showing that preoperative PFT is not helpful to predict PPC.

IL-23 mediates murine liver transplantation ischemia-reperfusion injury via IFN-γ/IRF-1 pathway.

Interleukin-23 (IL-23) is a proinflammatory cytokine initially studied in autoimmune disease that has been more recently linked to innate immunity. We observed that the expression of IL-23 is upregulated during hypoxia in a hepatocyte and nonparenchymal cell (NPC) coculture system, as well as during ischemia-reperfusion (I/R) injury in the liver. Interferon regulatory factor-1 (IRF-1) is a transcription factor that induces expression of multiple inflammatory cytokines and has been shown to play a critical role in liver I/R injury. We observed that IL-23 signaling induces not only the IL-17/chemokine (C-X-C motif) ligand 2 (CXCL2) pathway but also the IFN-γ/IRF-1 pathway. Quantification of cytokine genes revealed increased liver expression of IL-17a, CXCL2, and IRF-1 messenger RNA during liver transplantation. Recombinant IL-23 treated hepatocytes, and NPC coculture led to IL-17, CXCL2, IFN-γ, and IRF-1 expression. With anti-IL-17 and anti-Ly6G antibody neutralization, neutrophil recruitment and IFN-γ production were decreased during warm I/R injury. Overexpression of IL-23 in vivo through use of an adenovirus vector also led to expression of IL-17, CXCL2, IFN-γ, and IRF-1. The increased expression of IL-23 also led to increased apoptosis in the liver. By neutralization of IL-23 through use of an anti-IL-23p19 antibody, we were able to attenuate liver damage in a wild-type but not a natural killer T (NKT) cell-deficient mouse. This suggests that IL-23 signaling shares a common pathway with NKT cells. In conclusion, IL-23 is induced early by I/R in the liver. Its signaling leads to activation of the IL-17/CXCL2 and IFN-γ/IRF-1 pathways, resulting in increased apoptosis and necrosis. NEW & NOTEWORTHY IL-23 is expressed early during cold ischemia-reperfusion (I/R), and this expression is associated with expression of IL-17 and chemokine (C-X-C motif) ligand 2. Neutralization of IL-23 during cold I/R can significantly reduce liver damage as well as decrease cytokine production and neutrophil infiltration in the liver. IL-23 appears to activate IFN-γ production in natural killer T cells within the liver which, in turn, activates interferon regulatory factor-1, a known inflammatory transcription factor during I/R injury.

Partial Bile Duct Ligation in the Mouse: A Controlled Model of Localized Obstructive Cholestasis.

In rodents, complete bile duct ligation (cBDL) of the common bile duct is an established surgical technique for studying obstructive cholestasis and bile duct proliferation. However, long-term experiments can lead to increased morbidity and mortality. In select mouse strains with underlying liver disease, meaningful comparisons can be made even with ligation of a single lobe of the liver, which can reduce animal losses and expenses. Here, we describe partial bile duct ligation (pBDL) in the mouse, in which only the left hepatic bile duct is ligated, causing biliary obstruction in the left lobe but not the remaining lobes. With careful microsurgical technique, pBDL experiments can be cost-effective, since the unligated lobe serves as an internal control to the ligated lobes, when subjected to the same conditions in the same animal. Unlike cBDL, a separate sham-operated control group is not necessary. pBDL is highly useful to directly compare localized versus systemic effects of cholestasis and other retained bile components. pBDL can also be repurposed as a novel method to investigate mechanisms related to medications and cell migration.

Graft-infiltrating PD-L1hi cross-dressed dendritic cells regulate antidonor T cell responses in mouse liver transplant tolerance.

Although a key role of cross-dressing has been established in immunity to viral infection and more recently in the instigation of transplant rejection, its role in tolerance is unclear. We investigated the role of intragraft dendritic cells (DCs) and cross-dressing in mouse major histocompatibility complex (MHC)-mismatched liver transplant tolerance that occurs without therapeutic immunosuppression. Although donor interstitial DCs diminished rapidly after transplantation, they were replaced in the liver by host DCs that peaked on postoperative day (POD) 7 and persisted indefinitely. Approximately 60% of these recipient DCs displayed donor MHC class I, indicating cross-dressing. By contrast, only a very minor fraction (0%-2%) of cross-dressed DCs (CD-DCs) was evident in the spleen. CD-DCs sorted from liver grafts expressed much higher levels of T cell inhibitory programed death ligand 1 (PD-L1) and high levels of interleukin-10 compared with non-CD-DCs (nCD-DCs) isolated from the graft. Concomitantly, high incidences of programed death protein 1 (PD-1)hi T cell immunoglobulin and mucin domain containing 3 (TIM-3)+ exhausted graft-infiltrating CD8+ T cells were observed. Unlike nCD-DCs, the CD-DCs failed to stimulate proliferation of allogeneic T cells but markedly suppressed antidonor host T cell proliferation. CD-DCs were much less evident in allografts from DNAX-activating protein of 12 kDa (DAP12)-/- donors that were rejected acutely. CONCLUSION: These findings suggest that graft-infiltrating PD-L1hi CD-DCs may play a key role in the regulation of alloimmunity and in the induction of liver transplant tolerance. (Hepatology 2018;67:1499-1515).

Modification of the N-Terminus of a Calcium Carbonate Precipitating Peptide Affects Calcium Carbonate Mineralization.

BACKGROUND: A core sequence (the 9 C-terminal residues) of calcification-associated peptide (CAP- 1) isolated from the exoskeleton of the red swamp crayfish was previously shown to control calcium carbonate precipitation with chitin. In addition, a modified core sequence in which the phosphorylated serine at the N terminus is replaced with serine exhibits was also previously shown to alter precipitation characteristics with chitin. OBJECTIVES: We focused on calcium carbonate precipitation and attempted to elucidate aspects of the mechanism underlying mineralization. We attempted to evaluate in detail the effects of modifying the N-terminus in the core sequence on calcium carbonate mineralization without chitin. METHODS: The peptide modifications included phosphorylation, dephosphorylation, and a free or acetylated Nterminus. The peptides were synthesized manually on Wang resin using the DIPCI-DMAP method for the first residue, and Fmoc solid phase peptide synthesis with HBTU-HOBt for the subsequent residues. Prior to calcium carbonate precipitation, calcium carbonate was suspended in MilliQ water. Carbon dioxide gas was bubbled into the stirred suspension, then the remaining solid CaCO3 was removed by filtration. The concentration of calcium ions in the solution was determined by standard titration with ethylenediaminetetraacetate. Calcium carbonate precipitation was conducted in a micro tube for 3 h at 37°C. We used the micro-scale techniques AFM (atomic force microscopy) and TEM (transmission electron microscopy), and the macro-scale techniques chelate titration, HPLC, gel filtration, CD (circular dichroism) and DLS (dynamic light scattering). RESULTS: We determined the morphologies of the calcium carbonate deposits using AFM and TEM. The pS peptide provided the best control of the shape and size of the calcium carbonate round particles. The acetylated peptides (Ac-S and Ac-pS) provided bigger particles with various shapes. S peptide provided a mixture of bigger particles and amorphous particles. We verified these findings using DLS. All the peptide samples produced nanostructures of the expected size in agreement with the AFM and TEM results. We estimated the abilities of these peptides to precipitate calcium carbonate by determining the residual calcium hydrogen carbonate concentration by standard titration with ethylenediaminetetraacetate after calcium carbonate precipitation. The Ac-pS peptide showed the lowest residual calcium hydrogen carbonate concentration whereas the S peptide showed the highest, suggesting that the precipitating activities of these peptides towards calcium carbonate correlated with peptide net charge. Then the gel filtration results showed a large oligomer peak and a small oligomer/monomer peak for all peptide samples in agreement with the AFM, TEM and DLS results. CD measurements showed that all the peptides formed random-coil-like structures. Thus, we used both macro- and micro-observation techniques such as chelate titration, DLS, AFM and TEM to show that the calcium carbonate precipitating activities of four derivatives of the core sequence of CAP-1 may correlate with the peptide net charge. CONCLUSION: These peptides mainly act as a catalyst rather than as a binder or component of the calcium carbonate deposits (as a template). On the other hand, the morphologies of the calcium carbonate deposits appeared to be dependent on the ability of the peptide to assemble and act as a template. Consequently, elucidating the relationship between peptide sequence and the ability of the peptide to assemble would be indispensable for controlling precipitate morphologies in the near future. This knowledge would provide important clues for elucidating the relationship between peptide sequence and mineralization ability, including deposit morphology and precipitating activity, for use in nanobiochemistry and materials chemistry research.

Physician attire in the intensive care unit in Japan influences visitors' perception of care.

PURPOSE: The objective of this study is to evaluate the impact of physician attire and behavior on perceptions of care by ICU visitors in Japan. MATERIALS AND METHODS: Visitors were surveyed including 117 at a community hospital and 106 at a university hospital. Demographic data (age, gender, relationship to patient, length of stay) were collected. A seven-point Likert scale (1=strongly agree, 4=neutral, 7=strongly disagree) was used to judge physician attire (name tag, white coat, scrubs, short sleeve shirts, blue jeans, sneakers, clogs), behavior (addressing a patient, carrying a snack) and overall effect on perception of care. RESULTS: There are no significant differences (p>0.05) in demographics comparing the two ICUs, except for increased length of stay at the university ICU. Visitors scored the importance of a name tag (median 2, Interquartile Range 1-2), white coat [3,1-4], addressing the patient by last name [2,1-3], wearing scrubs [3,2-4], sneakers [4,3-5], clogs [4,4-5], short sleeves (4,3.5-5), blue jeans [5,4-6], and carrying a snack [6,5-7]. Visitors scored "attire affects perceptions of care" as [3,2-4]. CONCLUSIONS: Physician attire in the ICU affects perceptions of care. Implementation of attire guidelines which require clothing that does not meet visitor preferences should be accompanied by education programs.

An isolated metachronous metastasis to the adrenal gland from a pancreatic neuroendocrine tumor: A case report.

INTRODUCTION: Pancreatic neuroendocrine tumors are rare. Treatment includes aggressive local management of the primary lesion and metastases, and systemic somatostatin. This is the first report of an isolated metachronous metastasis to the adrenal gland from a pancreatic neuroendocrine tumor that presented 90 months after the primary tumor. PRESENTATION OF CASE: The patient presented as a 53yo man with a left upper quadrant mass and synchronous metastases to the spleen and liver (pancreatic neuroendocrine tumor T4N0M1, Stage IV), which were resected (CD56-, synaptophysin+, chromogranin+, Ki-67<1%). Over the next 90 months, he underwent five procedures to treat hepatic recurrences (2 liver resections and 3 percutaneous radiofrequency ablations). Serum PIVKA levels were elevated prior to treatment of four of six lesions and returned to baseline after therapy. He presents now, asymptomatic, with a right adrenal mass found on routine imaging and no other lesions. Serum PIVKA was elevated to 44mg/dL. The adrenal gland was resected and shown to be a metastasis (CD56+, synaptophysin+, chromogranin+, Ki-67 15-20%). DISCUSSION: This patient's clinical course reflects aggressive local therapy of the primary lesion and multiple metastatic lesions to three organs (liver, spleen, adrenal) over nearly eight years. The utility of serum PIVKA levels in patients with pancreatic neuroendocrine tumors is not previously reported and needs further investigation. CONCLUSION: This patient has a pancreatic neuroendocrine tumor with metastases to the spleen, liver and adrenal gland and elevated PIVKA levels with recurrent disease. These unique clinical features add to the diversity of clinical presentation of these rare tumors.

Influence of the Novel ATP-Competitive Dual mTORC1/2 Inhibitor AZD2014 on Immune Cell Populations and Heart Allograft Rejection.

BACKGROUND: Little is known about how new-generation adenosine triphosphate-competitive mechanistic target of rapamycin (mTOR) kinase inhibitors affect immunity and allograft rejection. METHODS: mTOR complex (C) 1 and 2 signaling in dendritic cells and T cells was analyzed by Western blotting, whereas immune cell populations in normal and heart allograft recipient mice were analyzed by flow cytometry. Alloreactive T cell proliferation was quantified in mixed leukocyte reaction; intracellular cytokine production and serum antidonor IgG levels were determined by flow analysis and immunofluorescence staining used to detect IgG in allografts. RESULTS: The novel target of rapamycin kinase inhibitor AZD2014 impaired dendritic cell differentiation and T cell proliferation in vitro and depressed immune cells and allospecific T cell responses in vivo. A 9-day course of AZD2014 (10 mg/kg, intraperitoneally, twice daily) or rapamycin (RAPA) (1 mg/kg, intraperitoneally, daily) prolonged median heart allograft survival time significantly (25 days for AZD2014, 100 days for RAPA, 9.5 days for control). Like RAPA, AZD2014 suppressed graft mononuclear cell infiltration, increased regulatory T cell to effector memory T cell ratios and reduced T follicular helper and B cells 7 days posttransplant. By 21 days (10 days after drug withdrawal), however, T follicular helper and B cells and donor-specific IgG1 and IgG2c antibody titers were significantly lower in RAPA-treated compared with AZD2014-treated mice. Elevated regulatory T cell to effector memory T cell ratios were maintained after RAPA, but not AZD2014 withdrawal. CONCLUSIONS: Immunomodulatory effects of AZD2014, unlike those of RAPA, were not sustained after drug withdrawal, possibly reflecting distinct pharmacokinetics or/and inhibitory effects of AZD2014 on mTORC2.

Bile Duct Ligation Induces ATZ Globule Clearance in a Mouse Model of α-1 Antitrypsin Deficiency.

α-1 Antitrypsin deficiency (A1ATD) can progress to cirrhosis and hepatocellular carcinoma; however, not all patients are susceptible to severe liver disease. In A1ATD, a toxic gain-of-function mutation generates insoluble ATZ "globules" in hepatocytes, overwhelming protein clearance mechanisms. The relationship between bile acids and hepatocytic autophagy is less clear but may involve altered gene expression pathways. Based on previous findings that bile duct ligation (BDL) induces autophagy, we hypothesized that retained bile acids may have hepatoprotective effects in PiZZ transgenic mice, which model A1ATD. We performed BDL and partial BDL (pBDL) in PiZZ mice, followed by analysis of liver tissues. PiZZ liver subjected to BDL showed up to 50% clearance of ATZ globules, with increased expression of autophagy proteins. Analysis of transcription factors revealed significant changes. Surprisingly nuclear TFEB, a master regulator of autophagy, remained unchanged. pBDL confirmed that ATZ globule clearance was induced by localized stimuli rather than diet or systemic effects. Several genes involved in bile metabolism were overexpressed in globule-devoid hepatocytes, compared to globule-containing cells. Retained bile acids led to a dramatic reduction of ATZ globules, with enhanced hepatocyte regeneration and autophagy. These findings support investigation of synthetic bile acids as potential autophagy-enhancing agents.

Regeneration and Cell Recruitment in an Improved Heterotopic Auxiliary Partial Liver Transplantation Model in the Rat.

BACKGROUND: Auxiliary partial liver transplantation (APLT) in humans is a therapeutic modality used especially to treat liver failure in children or congenital metabolic disease. Animal models of APLT have helped to explore therapeutic options. Though many groups have suggested improvements, standardizing the surgical procedure has been challenging. Additionally, the question of whether graft livers are reconstituted by recipient-derived cells after transplantation has been controversial. The aim of this study was to improve experimental APLT in rats and to assess cell recruitment in the liver grafts. METHODS: To inhibit recipient liver regeneration and to promote graft regeneration, we treated recipients with retrorsine and added arterial anastomosis. Using green fluorescence protein transgenic rats as recipients, we examined liver resident cell recruitment within graft livers by immunofluorescence costaining. RESULTS: In the improved APLT model, we achieved well-regenerated grafts that could maintain regeneration for at least 4 weeks. Regarding the cell recruitment, there was no evidence of recipient-derived hepatocyte, cholangiocyte, or hepatic stellate cell recruitment into the graft. Macrophages/monocytes, however, were consistently recruited into the graft and increased over time, which might be related to inflammatory responses. Very few endothelial cells showed colocalization of markers. CONCLUSIONS: We have successfully established an improved rat APLT model with arterial anastomosis as a standard technique. Using this model, we have characterized cell recruitment into the regenerating grafts.

Orthotopic mouse liver transplantation to study liver biology and allograft tolerance.

Orthotopic liver transplantation in the mouse is a powerful research tool that has led to important mechanistic insights into the regulation of hepatic injury, liver immunopathology, and transplant tolerance. However, it is a technically demanding surgical procedure. Setup of the orthotopic liver transplantation model comprises three main stages: surgery on the donor mouse; back-table preparation of the liver graft; and transplant of the liver into the recipient mouse. In this protocol, we describe our procedure in stepwise detail to allow efficient completion of both the donor and recipient operations. The protocol can result in consistently high technical success rates when performed by personnel experienced in the protocol. The technique can be completed in ∼2-3 h when performed by an individual who is well practiced in performing mouse transplantation in accordance with this protocol. We have achieved a perioperative survival rate close to 100%.

Contribution of alloantigens to hepatic ischemia/reperfusion injury: Roles of natural killer cells and innate immune recognition of nonself.

Hepatic ischemia/reperfusion injury (IRI) remains a major clinical problem and involves the innate immune system's recognition of "nonself." Considering the efficient nonself recognition by natural killer (NK) cells, we hypothesize in this study that hepatic IRI associated with liver transplantation (LT) could be augmented in allogeneic rather than in syngeneic (Syn) grafts due to alloantigen recognition by innate immune cells, especially by NK cells. Using green fluorescent protein (GFP)/Sprague-Dawley rats, we tested our hypothesis in a rat LT model with 18 hours of cold storage in University of Wisconsin solution. Hepatic IRI was significantly augmented in allografts with higher alanine transaminase levels, increased necrosis, and vigorous proinflammatory mediator up-regulation compared to Syn grafts. Injury increased in allografts associated with augmented GFP+ host leukocyte infiltration due to significantly increased host CD11b/c+ and RP-1(+) neutrophil recruitment. A large number of liver-resident (donor) mature CD11b/c+ NK cells quickly diminished from allografts, but not from Syn grafts. Depletion of mature NK cells from liver grafts with anti-asialo monosialotetrahexosylganglioside significantly improved hepatic IRI and reduced neutrophil infiltration and proinflammatory mediators. In conclusion, early innate immune responses were more significantly enhanced in allografts than in Syn grafts during hepatic IRI, in part through NK cell recognition of "missing self."

Liver transplantation in the mouse: Insights into liver immunobiology, tissue injury, and allograft tolerance.

The surgically demanding mouse orthotopic liver transplant model was first described in 1991. It has proved to be a powerful research tool for the investigation of liver biology, tissue injury, the regulation of alloimmunity and tolerance induction, and the pathogenesis of specific liver diseases. Liver transplantation in mice has unique advantages over transplantation of the liver in larger species, such as the rat or pig, because the mouse genome is well characterized and there is much greater availability of both genetically modified animals and research reagents. Liver transplant experiments using various transgenic or gene knockout mice have provided valuable mechanistic insights into the immunobiology and pathobiology of the liver and the regulation of graft rejection and tolerance over the past 25 years. The molecular pathways identified in the regulation of tissue injury and promotion of liver transplant tolerance provide new potential targets for therapeutic intervention to control adverse inflammatory responses/immune-mediated events in the hepatic environment and systemically. In conclusion, orthotopic liver transplantation in the mouse is a valuable model for gaining improved insights into liver biology, immunopathology, and allograft tolerance that may result in therapeutic innovation in the liver and in the treatment of other diseases.