Browsing by Subject "Immunosuppressive Agents"
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Item Open Access A model of sequential heart and composite tissue allotransplant in rats.(Plast Reconstr Surg, 2010-07) Yang, Jun; Erdmann, Detlev; Chang, JC; Komatsu, Issei; Zhang, YiXin; Wang, DanRu; Hodavance, Michael S; Hollenbeck, Scott T; Levinson, Howard; Klitzman, Bruce; Levin, LSBACKGROUND: Some of the 600,000 patients with solid organ allotransplants need reconstruction with a composite tissue allotransplant, such as the hand, abdominal wall, or face. The aim of this study was to develop a rat model for assessing the effects of a secondary composite tissue allotransplant on a primary heart allotransplant. METHODS: Hearts of Wistar Kyoto rats were harvested and transplanted heterotopically to the neck of recipient Fisher 344 rats. The anastomoses were performed between the donor brachiocephalic artery and the recipient left common carotid artery, and between the donor pulmonary artery and the recipient external jugular vein. Recipients received cyclosporine A for 10 days only. Heart rate was assessed noninvasively. The sequential composite tissue allotransplant consisted of a 3 x 3-cm abdominal musculocutaneous flap harvested from Lewis rats and transplanted to the abdomen of the heart allotransplant recipients. The abdominal flap vessels were connected to the femoral vessels. No further immunosuppression was administered following the composite tissue allotransplant. Ten days after composite tissue allotransplantation, rejection of the heart and abdominal flap was assessed histologically. RESULTS: The rat survival rate of the two-stage transplant surgery was 80 percent. The transplanted heart rate decreased from 150 +/- 22 beats per minute immediately after transplant to 83 +/- 12 beats per minute on day 20 (10 days after stopping immunosuppression). CONCLUSIONS: This sequential allotransplant model is technically demanding. It will facilitate investigation of the effects of a secondary composite tissue allotransplant following primary solid organ transplantation and could be useful in developing future immunotherapeutic strategies.Item Open Access A pilot study of IL-2Rα blockade during lymphopenia depletes regulatory T-cells and correlates with enhanced immunity in patients with glioblastoma.(PLoS One, 2012) Sampson, John H; Schmittling, Robert J; Archer, Gary E; Congdon, Kendra L; Nair, Smita K; Reap, Elizabeth A; Desjardins, Annick; Friedman, Allan H; Friedman, Henry S; Herndon, James E; Coan, April; McLendon, Roger E; Reardon, David A; Vredenburgh, James J; Bigner, Darell D; Mitchell, Duane ABACKGROUND: Preclinical studies in mice have demonstrated that the prophylactic depletion of immunosuppressive regulatory T-cells (T(Regs)) through targeting the high affinity interleukin-2 (IL-2) receptor (IL-2Rα/CD25) can enhance anti-tumor immunotherapy. However, therapeutic approaches are complicated by the inadvertent inhibition of IL-2Rα expressing anti-tumor effector T-cells. OBJECTIVE: To determine if changes in the cytokine milieu during lymphopenia may engender differential signaling requirements that would enable unarmed anti-IL-2Rα monoclonal antibody (MAbs) to selectively deplete T(Regs) while permitting vaccine-stimulated immune responses. METHODOLOGY: A randomized placebo-controlled pilot study was undertaken to examine the ability of the anti-IL-2Rα MAb daclizumab, given at the time of epidermal growth factor receptor variant III (EGFRvIII) targeted peptide vaccination, to safely and selectively deplete T(Regs) in patients with glioblastoma (GBM) treated with lymphodepleting temozolomide (TMZ). RESULTS AND CONCLUSIONS: Daclizumab treatment (n = 3) was well-tolerated with no symptoms of autoimmune toxicity and resulted in a significant reduction in the frequency of circulating CD4+Foxp3+ TRegs in comparison to saline controls (n = 3)( p = 0.0464). A significant (p<0.0001) inverse correlation between the frequency of TRegs and the level of EGFRvIII specific humoral responses suggests the depletion of TRegs may be linked to increased vaccine-stimulated humoral immunity. These data suggest this approach deserves further study. TRIAL REGISTRATION: ClinicalTrials.gov NCT00626015.Item Open Access Barriers to Taking Medications for Systemic Lupus Erythematosus: A Qualitative Study of Racial Minority Patients, Lupus Providers, and Clinic Staff.(Arthritis care & research, 2022-09) Sun, Kai; Corneli, Amy L; Dombeck, Carrie; Swezey, Teresa; Rogers, Jennifer L; Criscione-Schreiber, Lisa G; Sadun, Rebecca E; Eudy, Amanda M; Doss, Jayanth; Bosworth, Hayden B; Clowse, Megan EBObjective
Underrepresented racial and ethnic minorities are disproportionately affected by systemic lupus erythematosus (SLE). Racial and ethnic minorities also have more severe SLE manifestations that require use of immunosuppressive medications, and often have lower rates of medication adherence. We aimed to explore barriers of adherence to SLE immunosuppressive medications among minority SLE patients.Methods
We conducted a qualitative descriptive study using in-depth interviews with a purposive sample of racial minority SLE patients taking oral immunosuppressants (methotrexate, azathioprine, or mycophenolate), and lupus clinic providers and staff. Interviews were audiorecorded, transcribed, and analyzed using applied thematic analysis. We grouped themes using the Capability, Opportunity, Motivation, Behavior conceptual model.Results
We interviewed 12 SLE patients (4 adherent, 8 nonadherent) and 12 providers and staff. We identified capability barriers to include external factors related to acquiring medications, specifically cost-, pharmacy-, and clinic-related issues; opportunity barriers to include external barriers to taking medications, specifically logistic- and medication-related issues; and motivation factors to include intrinsic barriers, encompassing patients' knowledge, beliefs, attitudes, and physical and mental health. The most frequently described barriers were cost, side effects, busyness/forgetting, and lack of understanding, although barriers differed by patient and adherence level, with logistic and intrinsic barriers described predominantly by nonadherent patients and side effects described predominantly by adherent patients.Conclusion
Our findings suggest that interventions may be most impactful if they are designed to facilitate logistics of taking medications and increase patients' motivation while allowing for personalization to address the individual differences in adherence barriers.Item Open Access Clinical and angiographic outcomes with everolimus eluting stents for the treatment of cardiac allograft vasculopathy.(Journal of interventional cardiology, 2014-02) Azarbal, Babak; Arbit, Boris; Ramaraj, Radhakrishnan; Kittleson, Michelle; Young, Amelia; Czer, Lawrence; Rafiei, Matthew; Currier, Jesse; Makkar, Raj; Kobashigawa, JonOBJECTIVES: This study aimed to examine clinical efficacy, safety, and intermediate clinical outcomes with everolimus-eluting stents (EESs) in patients with transplant coronary artery disease (TCAD). BACKGROUND: TCAD is a major cause of mortality in patients following orthotopic heart transplantation (OHT). Systemic everolimus in OHT patients has been shown to reduce TCAD. The safety and efficacy of an EES, the Xience V, have not been evaluated in this population. METHODS: Patients post-OHT with hemodynamically significant CAD who underwent percutaneous coronary intervention (PCI) with EES were included. Participants were maintained on dual antiplatelet therapy for 1-year post-PCI. We examined procedural success, in-hospital and 1-year mortality, stent thrombosis, angiographic restenosis, and myocardial infarction rates. All patients had follow-up angiography 1-year after PCI. Target vessel revascularization (TVR), target lesion revascularization (TLR), in-segment restenosis, target vessel failure (TVF), and lumen late loss were noted. RESULTS: PCI was performed in 34 de novo lesions in 21 patients, and 40 EES were placed. Procedural success rate was 100%. Average stent was 16.5 ± 5.1 mm long and 3.0 ± 0.6 mm in diameter. All patients had angiographic follow-up (409 ± 201 days). There was no stent thrombosis, deaths, or myocardial infarctions during follow-up. Two patients had focal in-stent restenosis. TLR rate was 5.9% (2/34), and TVR rate was 11.1% (3/27). Quantitative coronary angiography (QCA) showed stenosis diameter to be 19.98 ± 17.57%. CONCLUSIONS: Use of an EES is associated with a low incidence of TVR and TLR in patients with TCAD. Further studies are needed to determine whether PCI with EES changes long-term outcomes.Item Open Access Enhanced de novo alloantibody and antibody-mediated injury in rhesus macaques.(Am J Transplant, 2012-09) Page, EK; Page, AJ; Kwun, J; Gibby, AC; Leopardi, F; Jenkins, JB; Strobert, EA; Song, M; Hennigar, RA; Iwakoshi, N; Knechtle, SJChronic allograft rejection is a major impediment to long-term transplant success. Humoral immune responses to alloantigens are a growing clinical problem in transplantation, with mounting evidence associating alloantibodies with the development of chronic rejection. Nearly a third of transplant recipients develop de novo antibodies, for which no established therapies are effective at preventing or eliminating, highlighting the need for a nonhuman primate model of antibody-mediated rejection. In this report, we demonstrate that depletion using anti-CD3 immunotoxin (IT) combined with maintenance immunosuppression that included tacrolimus with or without alefacept reliably prolonged renal allograft survival in rhesus monkeys. In these animals, a preferential skewing toward CD4 repopulation and proliferation was observed, particularly with the addition of alefacept. Furthermore, alefacept-treated animals demonstrated increased alloantibody production (100%) and morphologic features of antibody-mediated injury. In vitro, alefacept was found to enhance CD4 effector memory T cell proliferation. In conclusion, alefacept administration after depletion and with tacrolimus promotes a CD4+memory T cell and alloantibody response, with morphologic changes reflecting antibody-mediated allograft injury. Early and consistent de novo alloantibody production with associated histological changes makes this nonhuman primate model an attractive candidate for evaluating targeted therapeutics.Item Open Access Interleukin-15 receptor blockade in non-human primate kidney transplantation.(Transplantation, 2010-04-27) Haustein, Silke; Kwun, Jean; Fechner, John; Kayaoglu, Ayhan; Faure, Jean-Pierre; Roenneburg, Drew; Torrealba, Jose; Knechtle, Stuart JBACKGROUND: Interleukin (IL)-15 is a chemotactic factor to T cells. It induces proliferation and promotes survival of activated T cells. IL-15 receptor blockade in mouse cardiac and islet allotransplant models has led to long-term engraftment and a regulatory T-cell environment. This study investigated the efficacy of IL-15 receptor blockade using Mut-IL-15/Fc in an outbred non-human primate model of renal allotransplantation. METHODS: Male cynomolgus macaque donor-recipient pairs were selected based on ABO typing, major histocompatibility complex class I typing, and carboxy-fluorescein diacetate succinimidyl ester-based mixed lymphocyte responses. Once animals were assigned to one of six treatment groups, they underwent renal transplantation and bilateral native nephrectomy. Serum creatinine level was monitored twice weekly and as indicated, and protocol biopsies were performed. Rejection was defined as a increase in serum creatinine to 1.5 mg/dL or higher and was confirmed histologically. Complete blood counts and flow cytometric analyses were performed periodically posttransplant; pharmacokinetic parameters of Mut-IL-15/Fc were assessed. RESULTS: Compared with control animals, Mut-IL-15/Fc-treated animals did not demonstrate increased graft survival despite adequate serum levels of Mut-IL-15/Fc. Flow cytometric analysis of white blood cell subgroups demonstrated a decrease in CD8 T-cell and natural killer cell numbers, although this did not reach statistical significance. Interestingly, two animals receiving Mut-IL-15/Fc developed infectious complications, but no infection was seen in control animals. Renal pathology varied widely. CONCLUSIONS: Peritransplant IL-15 receptor blockade does not prolong allograft survival in non-human primate renal transplantation; however, it reduces the number of CD8 T cells and natural killer cells in the peripheral blood.Item Open Access Lung Transplantation and the Era of the Sensitized Patient.(Frontiers in immunology, 2021-01) Young, Katherine A; Ali, Hakim A; Beermann, Kristi J; Reynolds, John M; Snyder, Laurie DLong term outcomes in lung transplant are limited by the development of chronic lung allograft dysfunction (CLAD). Within the past several decades, antibody-mediated rejection (AMR) has been recognized as a risk factor for CLAD. The presence of HLA antibodies in lung transplant candidates, "sensitized patients" may predispose patients to AMR, CLAD, and higher mortality after transplant. This review will discuss issues surrounding the sensitized patient, including mechanisms of sensitization, implications within lung transplant, and management strategies.Item Open Access Myelodysplastic syndrome evolving from aplastic anemia treated with immunosuppressive therapy: efficacy of hematopoietic stem cell transplantation.(Haematologica, 2014-12) Kim, Sung-Yong; Le Rademacher, Jennifer; Antin, Joseph H; Anderlini, Paolo; Ayas, Mouhab; Battiwalla, Minoo; Carreras, Jeanette; Kurtzberg, Joanne; Nakamura, Ryotaro; Eapen, Mary; Deeg, H JoachimA proportion of patients with aplastic anemia who are treated with immunosuppressive therapy develop clonal hematologic disorders, including post-aplastic anemia myelodysplastic syndrome. Many will proceed to allogeneic hematopoietic stem cell transplantation. We identified 123 patients with post-aplastic anemia myelodysplastic syndrome who from 1991 through 2011 underwent allogeneic hematopoietic stem cell transplantation, and in a matched-pair analysis compared outcome to that in 393 patients with de novo myelodysplastic syndrome. There was no difference in overall survival. There were no significant differences with regard to 5-year probabilities of relapse, non-relapse mortality, relapse-free survival and overall survival; these were 14%, 40%, 46% and 49% for post-aplastic anemia myelodysplastic syndrome, and 20%, 33%, 47% and 49% for de novo myelodysplastic syndrome, respectively. In multivariate analysis, relapse (hazard ratio 0.71; P=0.18), non-relapse mortality (hazard ratio 1.28; P=0.18), relapse-free survival (hazard ratio 0.97; P=0.80) and overall survival (hazard ratio 1.02; P=0.88) of post-aplastic anemia myelodysplastic syndrome were similar to those of patients with de novo myelodysplastic syndrome. Cytogenetic risk was independently associated with overall survival in both groups. Thus, transplant success in patients with post-aplastic anemia myelodysplastic syndrome was similar to that in patients with de novo myelodysplastic syndrome, and cytogenetics was the only significant prognostic factor for post-aplastic anemia myelodysplastic syndrome patients.Item Open Access Outcome of transplantation for acute lymphoblastic leukemia in children with Down syndrome.(Pediatric blood & cancer, 2014-06) Hitzler, Johann K; He, Wensheng; Doyle, John; Cairo, Mitchell; Camitta, Bruce M; Chan, Ka Wah; Diaz Perez, Miguel A; Fraser, Christopher; Gross, Thomas G; Horan, John T; Kennedy-Nasser, Alana A; Kitko, Carrie; Kurtzberg, Joanne; Lehmann, Leslie; O'Brien, Tracey; Pulsipher, Michael A; Smith, Franklin O; Zhang, Mei-Jie; Eapen, Mary; Carpenter, Paul A; CIBMTR Pediatric Cancer Working CommitteeWe report on 27 patients with Down syndrome (DS) and acute lymphoblastic leukemia (ALL) who received allogeneic hematopoietic cell transplantation (HCT) between 2000 and 2009. Seventy-eight percent of patients received myeloablative conditioning and 52% underwent transplantation in second remission. Disease-free survival (DFS) was 24% at a median of 3 years. Post-transplant leukemic relapse was more frequent than expected for children with DS-ALL (54%) than for non-DS ALL. These data suggest leukemic relapse rather than transplant toxicity is the most important cause of treatment failure. Advancements in leukemia control are especially needed for improvement in HCT outcomes for DS-ALL.Item Open Access Pre-engraftment syndrome after myeloablative dual umbilical cord blood transplantation: risk factors and response to treatment.(Bone marrow transplantation, 2013-07) Kanda, J; Kaynar, L; Kanda, Y; Prasad, VK; Parikh, SH; Lan, L; Shen, T; Rizzieri, DA; Long, GD; Sullivan, KM; Gasparetto, C; Chute, JP; Morris, A; Winkel, S; McPherson, J; Kurtzberg, J; Chao, NJ; Horwitz, MEHigh fevers and/or rashes prior to neutrophil engraftment are frequently observed after umbilical cord blood (UCB) transplantation, and the condition is referred to as pre-engraftment syndrome (PES). Few studies have evaluated the risk factors for and treatment response to PES. Therefore, we retrospectively characterized PES in 57 consecutive engrafted patients (≥ 12 years old) who received myeloablative dual UCB transplantation. All patients received TBI (≥ 13.2 Gy)-based myeloablative conditioning. Tacrolimus (n=35) or CYA (n=22) combined with mycophenolate mofetil was used as GVHD prophylaxis. PES was defined as the presence of non-infectious fever (≥ 38.5 °C) and/or rash prior to or on the day of neutrophil engraftment. The incidence (95% confidence interval) of PES was 77% (66-88%). The incidence of PES was significantly higher in patients who received CYA as a GVHD prophylaxis than those who received tacrolimus (P<0.001), and this association was confirmed in the multivariate analysis. The occurrence of PES did not impact OS or tumor relapse, although it may have increased non-relapse mortality (P=0.071). The incidence of acute GHVD or treatment-related mortality was not influenced by the choice to use corticosteroids to treat PES. This study suggests that use of CYA for GVHD prophylaxis increases the risk of PES following dual UCB transplantation.Item Open Access Structure-Guided Synthesis of FK506 and FK520 Analogs with Increased Selectivity Exhibit In Vivo Therapeutic Efficacy against Cryptococcus.(mBio, 2022-06) Hoy, Michael J; Park, Eunchong; Lee, Hyunji; Lim, Won Young; Cole, D Christopher; DeBouver, Nicholas D; Bobay, Benjamin G; Pierce, Phillip G; Fox, David; Ciofani, Maria; Juvvadi, Praveen R; Steinbach, William; Hong, Jiyong; Heitman, JosephCalcineurin is an essential virulence factor that is conserved across human fungal pathogens, including Cryptococcus neoformans, Aspergillus fumigatus, and Candida albicans. Although an excellent target for antifungal drug development, the serine-threonine phosphatase activity of calcineurin is conserved in mammals, and inhibition of this activity results in immunosuppression. FK506 (tacrolimus) is a naturally produced macrocyclic compound that inhibits calcineurin by binding to the immunophilin FKBP12. Previously, our fungal calcineurin-FK506-FKBP12 structure-based approaches identified a nonconserved region of FKBP12 that can be exploited for fungus-specific targeting. These studies led to the design of an FK506 analog, APX879, modified at the C-22 position, which was less immunosuppressive yet maintained antifungal activity. We now report high-resolution protein crystal structures of fungal FKBP12 and a human truncated calcineurin-FKBP12 bound to a natural FK506 analog, FK520 (ascomycin). Based on information from these structures and the success of APX879, we synthesized and screened a novel panel of C-22-modified compounds derived from both FK506 and FK520. One compound, JH-FK-05, demonstrates broad-spectrum antifungal activity in vitro and is nonimmunosuppressive in vivo. In murine models of pulmonary and disseminated C. neoformans infection, JH-FK-05 treatment significantly reduced fungal burden and extended animal survival alone and in combination with fluconazole. Furthermore, molecular dynamic simulations performed with JH-FK-05 binding to fungal and human FKBP12 identified additional residues outside the C-22 and C-21 positions that could be modified to generate novel FK506 analogs with improved antifungal activity. IMPORTANCE Due to rising rates of antifungal drug resistance and a limited armamentarium of antifungal treatments, there is a paramount need for novel antifungal drugs to treat systemic fungal infections. Calcineurin has been established as an essential and conserved virulence factor in several fungi, making it an attractive antifungal target. However, due to the immunosuppressive action of calcineurin inhibitors, they have not been successfully utilized clinically for antifungal treatment in humans. Recent availability of crystal structures of fungal calcineurin-bound inhibitor complexes has enabled the structure-guided design of FK506 analogs and led to a breakthrough in the development of a compound with increased fungal specificity. The development of a calcineurin inhibitor with reduced immunosuppressive activity and maintained therapeutic antifungal activity would add a significant tool to the treatment options for these invasive fungal infections with exceedingly high rates of mortality.