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Item Challenges with Intestine and Multivisceral Re-Transplantation: Importance of Timing of Re-Transplantation and Optimal Immunosuppression(Springer, 2018-02-06) Kubal, Chandrashekhar A.; Pennington, Catherine; Fridell, Jonathan; Ekser, Burcin; Muhaylov, Plamen; Mangus, Richard; Surgery, School of MedicineBACKGROUND Patients undergoing re-transplantation often receive high doses of immunosuppression, which may lead to an immunocompromised status of the recipient. This study investigates the outcomes after intestine/multivisceral re-transplantation. MATERIAL AND METHODS Clinical outcomes of 23 patients undergoing 24 re-transplantations at a single intestine transplant center were reviewed. Bone marrow suppression was used as a surrogate marker of immunocompromised status, and was defined as platelet count <50 k/mm3 and absolute lymphocyte count <200/mm³. RESULTS All re-transplants except one were liver inclusive. Fifteen of 23 patients died at a median time of 12 months (range 0.2-75) after re-transplantation. Of the 15 deaths, nine (60%) resulted from complications associated with a compromised host immune status: graft versus host disease (GVHD) affecting bone marrow (three cases), persistent viral infection (three cases), post-transplant lymphoproliferative disorder (PTLD (one case), metastatic cancer (one case), multi-drug resistant polymicrobial sepsis (one case). Four deaths (27%) resulted from severe rejection. Non-survivors were more likely to have received alemtuzumab, and had higher incidence of bone marrow suppression. In addition to immunocompromised status and rejection, the use of alemtuzumab was associated with mortality after intestinal/multivisceral re-transplantation. CONCLUSIONS High mortality was associated with intestine/multivisceral re-transplantation. To improve clinical outcomes of intestine and multivisceral transplantation, it is important to allow reconstitution of host immunity. Longer interval between the two transplantations, and strategies such as allograft specific immunosuppression, may spare the host from the devastating effects of potent immunosuppression currently used.Item Different brain responses to electro-acupuncture and moxibustion treatment in patients with Crohn's disease(Nature Publishing Group, 2016-11-18) Bao, Chunhui; Liu, Peng; Liu, Huirong; Jin, Xiaoming; Calhoun, Vince D.; Wu, Luyi; Shi, Yin; Zhang, Jianye; Zeng, Xiaoqing; Ma, Lili; Qin, Wei; Zhang, Jingzhi; Liu, Xiaoming; Tian, Jie; Wu, Huangan; Department of Anatomy and Cell Biology, School of MedicineThis study aimed to investigate changes in resting state brain activity in remissive Crohn's Disease (CD) patients after electro-acupuncture or moxibustion treatment. Fifty-two CD patients and 36 healthy subjects were enrolled, and 36 patients were equally and randomly assigned to receive either electro-acupuncture or moxibustion treatment for twelve weeks. We used resting state functional magnetic resonance imaging to assess Regional Homogeneity (ReHo) levels, and Crohn's Disease Activity Index (CDAI) and Inflammatory Bowel Disease Questionnaire (IBDQ) scores to evaluate disease severity and quality of life. The results show that (i) The ReHo levels in CD patients were significantly increased in cortical but decreased in subcortical areas, and the coupling between them was declined. (ii) Both treatments decreased CDAI, increased IBDQ scores, and normalized the ReHo values of the cortical and subcortical regions. (iii) ReHo changes in multiple cortical regions were significantly correlated with CDAI score decreases. ReHo changes in several subcortical regions in the electro-acupuncture group, and those of several cortical regions in the moxibustion group, were correlated with reduced CDAI. These findings suggest that both treatments improved cortex-subcortical coupling in remissive CD patients, but electro-acupuncture regulated homeostatic afferent processing network, while moxibustion mainly regulated the default mode network of the brain.Item Hydrogen Sulfide Donor GYY4137 Acts Through Endothelial Nitric Oxide to Protect Intestine in Murine Models of Necrotizing Enterocolitis and Intestinal Ischemia(Elsevier, 2019-02) Drucker, Natalie A.; Jensen, Amanda R.; Te Winkel, Pieter Jan; Markel, Troy A.; Surgery, School of MedicineBACKGROUND: Necrotizing enterocolitis (NEC) in premature infants is often a devastating surgical condition with poor outcomes. GYY4137 is a long-acting donor of hydrogen sulfide, a gasotransmitter that is protective against intestinal injury in experimental NEC, likely through protection against injury secondary to ischemia. We hypothesized that administration of GYY4137 would improve mesenteric perfusion, reduce intestinal injury, and reduce inflammatory responses in experimental NEC and ischemia-reperfusion injury, and that these benefits would be mediated through endothelial nitric oxide synthase-dependent pathways. METHODS: NEC was induced in C57BL/6 wild-type (WT) and endothelial nitric oxide synthase (eNOS) knockout (eNOSKO) pups via maternal separation, formula feeding, enteral lipopolysaccharide, and intermittent hypoxic and hypothermic stress. Pups received daily intraperitoneal injections of 50 mg/kg GYY4137 or phosphate buffered saline vehicle. In separate groups, adult male WT and eNOSKO mice underwent superior mesenteric artery occlusion for 60 min. Before abdominal closure, 50 mg/kg GYY4137 or phosphate buffered saline vehicle was administered into the peritoneal cavity. Laser doppler imaging was used to assess mesenteric perfusion of pups at baseline and on postnatal day 9, and the adult mice at baseline and 24 h after ischemic insult. After euthanasia, the terminal ileum of each animal was fixed, paraffin embedded, sectioned, and stained with hematoxylin and eosin. Sections were blindly graded using published injury scores. Intestinal tissue was homogenized and cytokines measured by ELISA. Data were compared using Mann-Whitney U test, and P-values <0.05 were significant. RESULTS: After NEC and ischemia reperfusion (I/R) injury, GYY4137 improved perfusion in WT mice compared to vehicle, but this effect was lost in the eNOSKO animals. Histologic injury followed a similar pattern with reduced intestinal injury in WT mice treated with GYY4137, and no significant improvement in the eNOSKO group. Cytokine expression after GYY4137 administration was altered by the ablation of eNOS in both NEC and I/R injury groups, with significant differences noted in Interleukin 6 and vascular endothelial growth factor. CONCLUSIONS: GYY4137, a long-acting donor of hydrogen sulfide, has potential as a therapeutic compound for NEC. It improves mesenteric perfusion and intestinal injury in experimental NEC and intestinal I/R injury, and these benefits appear to be mediated through eNOS-dependent pathways.Item IFN-γ mediates Paneth cell death via suppression of mTOR(eLife Sciences, 2021-10-11) Araujo, Alessandra; Safronova, Alexandra; Burger, Elise; López-Yglesias, Américo; Giri, Shilpi; Camanzo, Ellie T.; Martin, Andrew T.; Grivennikov, Sergei; Yarovinsky, Felix; Microbiology and Immunology, School of MedicinePaneth cells constitutively produce antimicrobial peptides and growth factors that allow for intestinal homeostasis, host protection, and intestinal stem cell replication. Paneth cells rely heavily on the glycolytic metabolic program, which is in part controlled by the kinase complex Mechanistic target of rapamycin (mTORC1). Yet, little is known about mTOR importance in Paneth cell integrity under steady-state and inflammatory conditions. Our results demonstrate that IFN-γ, a crucial mediator of the intestinal inflammation, acts directly on murine Paneth cells to alter their mitochondrial integrity and membrane potential, resulting in an TORC1-dependent cell death mechanism distinct from canonical cell death pathways including apoptosis, necroptosis, and pyroptosis. These results were established with the purified cytokine and a physiologically relevant common Th1-inducing human parasite Toxoplasma gondii. Given the crucial role for IFN-γ, which is a cytokine frequently associated with the development of inflammatory bowel disease and compromised Paneth cell functions, the identified mechanisms underlying mTORC1-dependent Paneth cell death downstream of IFN-γ may provide promising novel approaches for treating intestinal inflammation.Item Parkinson disease-associated LRRK2 G2019S transgene disrupts marrow myelopoiesis and peripheral Th17 response(Wiley, 2017-10) Park, Jeongho; Lee, Jang-Won; Cooper, Scott C.; Broxmeyer, Hal E.; Cannon, Jason R.; Kim, Chang H.; Microbiology and Immunology, School of MedicineParkinson's disease (PD) is a neurodegenerative disease, whereas Crohn's disease is an inflammatory bowel disease. Interestingly, polymorphisms in the LRRK2 gene have been identified as risk factors for both diseases. LRRK2 G2019S is the most prevalent mutation found in PD. To gain insights into the role of the LRRK2 G2019S gene on the development and activation of the immune system in the brain-gut axis, we investigated the effect of LRRK2 G2019S on bone marrow myeloid progenitors and myeloid cell function in the periphery. We used bacterial artificial chromosome transgenic rats harboring the human LRRK2 G2019S gene. LRRK2 G2019S transgene decreased the numbers of monocytic and granulocytic progenitors in the bone marrow. However, the numbers of peripheral, immature myeloid cells with suppressive activity were increased in the gut and blood circulation of LRRK2 G2019S compared with control rats in various acute and chronic inflammatory responses. In inflammatory conditions, Th17 cell activity was suppressed, but tissue-associated phylum Bacteroidetes was abnormally increased in the intestine of LRRK2 G2019S rats. The abnormally expanded myeloid cells because of the LRRK2 G2019S gene were highly suppressive on Th17 cell differentiation. Moreover, we found that inhibition of LRRK2 kinase affects myeloid progenitors and myeloid cell differentiation. Taken together, the results indicate that abnormal LRRK2 activity can alter bone marrow myelopoiesis, peripheral myeloid cell differentiation, and intestinal immune homeostasis. These findings may have ramifications in immune and inflammatory responses in patients with LRRK2 abnormalities.Item Stem cell therapy in necrotizing enterocolitis: Current state and future directions(Elsevier, 2018-02) Drucker, Natalie A.; McCulloh, Christopher J.; Li, Bo; Pierro, Agostino; Besner, Gail E.; Markel, Troy A.; Surgery, School of MedicineStem cell therapy is a promising treatment modality for necrotizing enterocolitis. Among the many promising stem cells identified to date, it is likely that mesenchymal stem cells will be the most useful and practical cell-based therapies for this condition. Using acellular components such as exosomes or other paracrine mediators are promising as well. Multiple mechanisms are likely at play in the positive effects provided by these cells, and further research is underway to further elucidate these effects.