Person: Tullius, Stefan
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Tullius
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Stefan
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Tullius, Stefan
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Publication Ischemia augments alloimmune injury through IL-6-driven CD4+ alloreactivity(Nature Publishing Group UK, 2018) Uehara, Mayuko; Solhjou, Zhabiz; Banouni, Naima; Kasinath, Vivek; Xiaqun, Ye; Dai, Li; Yilmam, Osman; Yilmaz, Mine; Ichimura, Takaharu; Fiorina, Paolo; Martins, Paulo N.; Ohori, Shunsuke; Guleria, Indira; Maarouf, Omar H.; Tullius, Stefan; McGrath, Martina; Abdi, RezaIschemia reperfusion injuries (IRI) are unavoidable in solid organ transplantation. IRI augments alloimmunity but the mechanisms involved are poorly understood. Herein, we examined the effect of IRI on antigen specific alloimmunity. We demonstrate that ischemia promotes alloimmune activation, leading to more severe histological features of rejection, and increased CD4+ and CD8+ T cell graft infiltration, with a predominantly CD8+ IFNγ+ infiltrate. This process is dependent on the presence of alloreactive CD4+ T cells, where depletion prevented infiltration of ischemic grafts by CD8+ IFNγ+ T cells. IL-6 is a known driver of ischemia-induced rejection. Herein, depletion of donor antigen-presenting cells reduced ischemia-induced CD8+ IFNγ+ allograft infiltration, and improved allograft outcomes. Following prolonged ischemia, accelerated rejection was observed despite treatment with CTLA4Ig, indicating that T cell costimulatory blockade failed to overcome the immune activating effect of IRI. However, despite severe ischemic injury, treatment with anti-IL-6 and CTLA4Ig blocked IRI-induced alloimmune injury and markedly improved allograft survival. We describe a novel pathway where IRI activates innate immunity, leading to upregulation of antigen specific alloimmunity, resulting in chronic allograft injury. Based on these findings, we describe a clinically relevant treatment strategy to overcome the deleterious effect of IRI, and provide superior long-term allograft outcomes.Publication Regulation of T cell alloimmunity by PI3Kγ and PI3Kδ(Nature Publishing Group UK, 2017) Uehara, Mayuko; McGrath, Martina; Ohori, Shunsuke; Solhjou, Zhabiz; Banouni, Naima; Routray, Sujit; Evans, Catherine; DiNitto, Jonathan P.; ElKhal, Abdallah; Turka, Laurence; Strom, Terry B.; Tullius, Stefan; Winkler, David G.; Azzi, Jamil; Abdi, RezaPhosphatidylinositol-3-kinases (PI3K) γ and δ are preferentially enriched in leukocytes, and defects in these signaling pathways have been shown to impair T cell activation. The effects of PI3Kγ and PI3Kδ on alloimmunity remain underexplored. Here, we show that both PI3Kγ −/− and PI3Kδ D910A/D910A mice receiving heart allografts have suppression of alloreactive T effector cells and delayed acute rejection. However, PI3Kδ mutation also dampens regulatory T cells (Treg). After treatment with low dose CTLA4-Ig, PI3Kγ −/−, but not PI3Κδ D910A/D910A, recipients exhibit indefinite prolongation of heart allograft survival. PI3Kδ D910A/D910A Tregs have increased apoptosis and impaired survival. Selective inhibition of PI3Kγ and PI3Kδ (using PI3Kδ and dual PI3Kγδ chemical inhibitors) shows that PI3Kγ inhibition compensates for the negative effect of PI3Kδ inhibition on long-term allograft survival. These data serve as a basis for future PI3K-based immune therapies for transplantation.Publication Three Patients with Full Facial Transplantation(New England Journal of Medicine (NEJM/MMS), 2012) Pomahac, Bohdan; Pribaz, Julian; Eriksson, Elof; Bueno, Ericka M.; Diaz-Siso, J. Rodrigo; Rybicki, Frank John; Annino, Donald James; Orgill, Dennis; Caterson, Edward; Caterson, Stephanie; Carty, Matthew; Chun, Yoon; Sampson, Christian; Janis, Jeffrey E.; Alam, Daniel S.; Saavedra, Arturo; Molnar, Joseph A.; Edrich, Thomas; Marty, Francisco; Tullius, StefanUnlike conventional reconstruction, facial transplantation seeks to correct severe deformities in a single operation. We report on three patients who received full-face transplants at our institution in 2011 in operations that aimed for functional restoration by coaptation of all main available motor and sensory nerves. We enumerate the technical challenges and postoperative complications and their management, including single episodes of acute rejection in two patients. At 6 months of follow-up, all facial allografts were surviving, facial appearance and function were improved, and glucocorticoids were successfully withdrawn in all patients.Publication Independent effects of sham laparotomy and anesthesia on hepatic microRNA expression in rats(BioMed Central, 2014) Werner, Wiebke; Sallmon, Hannes; Leder, Annekatrin; Lippert, Steffen; Reutzel-Selke, Anja; Morgül, Mehmet Haluk; Jonas, Sven; Dame, Christof; Neuhaus, Peter; Iacomini, John; Tullius, Stefan; Sauer, Igor M; Raschzok, NathanaelBackground: Studies on liver regeneration following partial hepatectomy (PH) have identified several microRNAs (miRNAs) that show a regulated expression pattern. These studies involve major surgery to access the liver, which is known to have intrinsic effects on hepatic gene expression and may also affect miRNA screening results. We performed two-third PH or sham laparotomy (SL) in Wistar rats to investigate the effect of both procedures on miRNA expression in liver tissue and corresponding plasma samples by microarray and qRT-PCR analyses. As control groups, non-treated rats and rats undergoing anesthesia only were used. Results: We found that 49 out of 323 miRNAs (15%) were significantly deregulated after PH in liver tissue 12 to 48 hours postoperatively (>20% change), while 45 miRNAs (14%) were deregulated following SL. Out of these miRNAs, 10 miRNAs were similarly deregulated after PH and SL, while one miRNA showed opposite regulation. In plasma, miRNA upregulation was observed for miR-133a and miR-133b following PH and SL, whereas miR-100 and miR-466c were similarly downregulated following anesthesia and surgery. Conclusions: We show that miRNAs are indeed regulated by sham laparotomy and anesthesia in rats. These findings illustrate the critical need for finding appropriate control groups in experimental surgery.Publication NAD+ protects against EAE by regulating CD4+ T-cell differentiation(Nature Pub. Group, 2014) Tullius, Stefan; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; de la Fuente, Miguel A.; Arredouani, Mohamed Simo; Camacho, Virginia; Tigges, John C.; Toxavidis, Vasilis; El Fatimy, Rachid; Smith, Brian D.; Vasudevan, Anju; ElKhal, AbdallahCD4+ T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD+) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4+IFNγ+IL-10+ T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD+ regulates CD4+ T-cell differentiation through tryptophan hydroxylase-1 (Tph1), independently of well-established transcription factors. In the presence of NAD+, the frequency of T-bet−/− CD4+IFNγ+ T cells was twofold higher than wild-type CD4+ T cells cultured in conventional T helper 1 polarizing conditions. Our findings unravel a new pathway orchestrating CD4+ T-cell differentiation and demonstrate that NAD+ may serve as a powerful therapeutic agent for the treatment of autoimmune and other diseases.Publication The importance of prevention of calciphylaxis in patients who are at risk and the potential fallibility of calcimimetics in the treatment of calciphylaxis for patients with secondary hyperparathyroidism(Oxford University Press, 2009) Khalpey, Zain; Nehs, Matthew; ElBardissi, Andrew W.; Semel, Marcus; Tullius, StefanA 43-year-old African American with end-stage renal disease (ESRD) associated with membranous nephropathy and a previously failed renal transplant had received cinacalcet to treat his secondary hyperparathyroidism. Serum calcium and phosphorus levels remained within normal limits, and serum parathyroid levels had dropped significantly following treatment initiation. However, within 7 months, the patient experienced extensive necrotic bilateral medial thigh ulcers. These were biopsied and found to be a result of calciphylaxis. The patient ultimately required an urgent subtotal parathyroidectomy and recovered well with completely healed ulcers.Publication Targeted Delivery of Immunomodulators to Lymph Nodes(2016) Azzi, Jamil; Yin, Qian; Uehara, Mayuko; Ohori, Shunsuke; Tang, Li; Cai, Kaimin; Ichimura, Takaharu; McGrath, Martina; Maarouf, Omar; Kefaloyianni, Eirini; Loughhead, Scott; Petr, Jarolim; Sun, Qidi; Kwon, Mincheol; Tullius, Stefan; von Andrian-Werburg, Ulrich; Cheng, Jianjun; Abdi, RezaSUMMARY Active-targeted delivery to lymph nodes represents a major advance toward more effective treatment of immune-mediated disease. The MECA79 antibody recognizes peripheral node address in molecules expressed by high endothelial venules of lymph nodes. By mimicking lymphocyte trafficking to the lymph nodes, we have engineered MECA79-coated microparticles containing an immunosuppressive medication, tacrolimus. Following intravenous administration, MECA79-bearing particles showed marked accumulation in the draining lymph nodes of transplanted animals. Using an allograft heart transplant model, we show that targeted lymph node delivery of microparticles containing tacrolimus can prolong heart allograft survival with negligible changes in tacrolimus serum level. Using MECA79 conjugation, we have demonstrated targeted delivery of tacrolimus to the lymph nodes following systemic administration, with the capacity for immune modulation in vivo.Publication Current status of vascularized composite tissue allotransplantation(BioMed Central, 2014) Edtinger, Karoline; Yang, Xiaoyong; Uehara, Hanae; Tullius, StefanVascularized composite tissue allotransplantation (VCA) offers treatment options of complex functional deficiencies that cannot be repaired with conventional reconstructive methods. VCAs consist of blocks of functional units comprising different tissue types such as skin, bone, muscle, nerves, blood vessels, tendons, ligaments and others, and are thus substantially different from the composition of organ transplants. The field of VCA has made fascinating progresses in the recent past. Among other VCAs, numerous successful hand, face and limb transplants have been performed in the world. At the same time, specific questions in regard to innate and adaptive immunity, consequences of ischemia/reperfusion injury, immunosuppression, preservation, and regenerative capacity remain. In spite of this, the field is poised to make significant advances in the near future.Publication NAD+ regulates Treg cell fate and promotes allograft survival via a systemic IL-10 production that is CD4+ CD25+ Foxp3+ T cells independent(Nature Publishing Group, 2016) ElKhal, Abdallah; Rodriguez Cetina Biefer, Hector; Heinbokel, Timm; Uehara, Hirofumi; Quante, Markus; Seyda, Midas; Schuitenmaker, Jeroen M.; Krenzien, Felix; Camacho, Virginia; de la Fuente, Miguel A.; Ghiran, Ionita; Tullius, StefanCD4+ CD25+ Foxp3+ Tregs have been shown to play a central role in immune homeostasis while preventing from fatal inflammatory responses, while Th17 cells have traditionally been recognized as pro-inflammatory mediators implicated in a myriad of diseases. Studies have shown the potential of Tregs to convert into Th17 cells, and Th17 cells into Tregs. Increasing evidence have pointed out CD25 as a key molecule during this transdifferentiation process, however molecules that allow such development remain unknown. Here, we investigated the impact of NAD+ on the fate of CD4+ CD25+ Foxp3+ Tregs in-depth, dissected their transcriptional signature profile and explored mechanisms underlying their conversion into IL-17A producing cells. Our results demonstrate that NAD+ promotes Treg conversion into Th17 cells in vitro and in vivo via CD25 cell surface marker. Despite the reduced number of Tregs, known to promote homeostasis, and an increased number of pro-inflammatory Th17 cells, NAD+ was able to promote an impressive allograft survival through a robust systemic IL-10 production that was CD4+ CD25+ Foxp3+ independent. Collectively, our study unravels a novel immunoregulatory mechanism of NAD+ that regulates Tregs fate while promoting allograft survival that may have clinical applications in alloimmunity and in a wide spectrum of inflammatory conditions.Publication Prolonged Graft Survival in Older Recipient Mice Is Determined by Impaired Effector T-Cell but Intact Regulatory T-Cell Responses(Public Library of Science, 2010) Denecke, Christian; Bedi, Damanpreet Singh; Ge, Xupeng; Kim, Irene Kyung-eun; Jurisch, Anke; Weiland, Anne; Habicht, Antje; Li, Xian Chang; Tullius, StefanElderly organ transplant recipients represent a fast growing segment of patients on the waiting list. We examined age-dependent CD4+ T-cell functions in a wild-type (WT) and a transgenic mouse transplant model and analyzed the suppressive function of old regulatory T-cells. We found that splenocytes of naïve old B6 mice contained significantly higher frequencies of T-cells with an effector/memory phenotype (CD4+CD44highCD62Llow). However, in-vitro proliferation (MLR) and IFNγ-production (ELISPOT) were markedly reduced with increasing age. Likewise, skin graft rejection was significantly delayed in older recipients and fewer graft infiltrating CD4+T-cells were observed. Old CD4+ T-cells demonstrated a significant impaired responsiveness as indicated by diminished proliferation and activation. In contrast, old alloantigen-specific CD4+CD25+FoxP3+ T-cells demonstrated a dose-dependent well-preserved suppressor function. Next, we examined characteristics of 18-month old alloreactive T-cells in a transgenic adoptive transfer model. Adoptively transferred old T-cells proliferated significantly less in response to antigen. Skin graft rejection was significantly delayed in older recipients, and graft infiltrating cells were reduced. In summary, advanced recipient age was associated with delayed acute rejection and impaired CD4+ T-cell function and proliferation while CD4+CD25+FoxP3+ T-cells (Tregs) showed a well-preserved function.