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J W Kupiec-Weglinski

Publications and source records attributed to J W Kupiec-Weglinski.

At least 19 recordsLinked to original sources
PubMed2006

FK330, a novel inducible nitric oxide synthase inhibitor, prevents ischemia and reperfusion injury in rat liver transplantation.

Nitric oxide (NO), produced via inducible NO synthase (iNOS), is implicated in the pathophysiology of liver ischemia/reperfusion injury (IRI). We examined the effects of a novel iNOS inhibitor, FK330 (FR260330), in well-defined rat liver IRI models. In a model of liver cold ischemia followed by ex vivo reperfusion, treatment with FK330 improved portal venous flow, increased bile production and decreased hepatocellular damage. FK330 prevented IRI in rat model of 40-h cold ischemia followed by syngeneic orthotopic liver transplantation (OLT), as evidenced by: (1) increased OLT survival (from 20% to 80%); (2) decreased hepatocellular damage (serum glutamic oxaloacetic transaminase/glutamic pyruvic transaminase levels); (3) improved histological features of IRI; (4) reduced intrahepatic leukocyte infiltration, as evidenced by decreased expression of P-selectin/intracellular adhesion molecule 1, ED-1/CD3 cells and neutrophils; (5) depressed lymphocyte activation, as evidenced by expression of pro-inflammatory cytokine (TNF-alpha, IL-1beta, IL-6) and chemokine (IP-10, MCP-1, MIP-2) programs; (6) prevented hepatic apoptosis and down-regulated Bax/Bcl-2 ratio. Thus, by modulating leukocyte trafficking and cell activation patterns, treatment of rats with FK330, a specific iNOS inhibitor, prevented liver IRI. These results provide the rationale for novel therapeutic approaches to maximize organ donor pool through the safer use of liver grafts despite prolonged periods of cold ischemia.

Animals↗
PubMed2005

Donor MHC class I peptides in conjunction with self-epitopes induce donor-specific tolerance in a dose-dependent manner but unable to abrogate chronic rejection.

Understanding specific tolerance mechanisms is a primary goal of transplantation science. We have previously shown that hosts treated with MHC class I protein have donor sequences in the alpha1-helix of the alpha1 domain on a background of self-epitopes, resulting in the development of donor-specific tolerance. However, the nature of class I alloantigenic determinants that regulate the alloimmune response remains unclear. The alpha1-helical sequence of RT1.A,1 which shares RT1.A(u) sequences, was substituted in the RT1.A(a) molecule to produce the composite [alpha1h(l/u)]-RT1.A(a) MHC class I allochimeric molecule. Immunodominant epitopes were identified within the hypervariable region of the alpha1 domain of RT1.A(a) (ACI), RT1.Al (Lewis, LEW), and RT1.A(u) (Wistar Furth [WF]). To clarify the mechanisms of tolerance development through presentation of donor-type immunogenic epitopes and cryptic self-epitopes we used synthetic peptides corresponding to donor immunogenic determinants with peptides derived from recipient self-sequences (RT1.A(a)--aa 10 to 49 P1 and 91 to 120 P3; and P2 RT1.A(l/u) 50 to 90). ACI recipients of LEW and WF cardiac allografts were injected through the portal vein (PV) at day 0 with four doses (2, 0.5, 0.25, and 0.125 mg/rat) of three peptide mixtures in conjunction with subtherapeutic CsA (10 mg/kg for 3 days). Allograft survival was strongly dose-dependent. Only low-dose regimens were consistent in tolerance induction, but such therapy did not abrogate development of chronic rejection (CR), unlike allochimeric therapy with soluble MHC class I protein. Different effects of protein or synthetic peptide therapies on development of CR suggest that development of specific tolerance is an active immunologic process and it depends on the form of allogeneic epitopes presented.

Animals↗
PubMed2005

HO-1 upregulation suppresses type 1 IFN pathway in hepatic ischemia/reperfusion injury.

Upregulation of heme oxygenase (HO)-1, a heat shock protein 32, protects against hepatic ischemia/reperfusion (I/R) injury. Activation of "innate" toll-like receptor (TLR) 4 system triggers the I/R injury cascade. This study explores cytoprotective functions of HO-1 overexpression following exogenous administration of cobalt protoporphyrin (CoPP), and its relationship with the TLR4 pathway in a model of mouse partial hepatic warm I/R injury. CoPP treatment markedly improved hepatic function and histology, and suppressed pro-inflammatory cytokine elaboration profile, as compared with untreated controls. Although administration of CoPP did not affect intrahepatic TLR4, it downregulated IFN-inducible protein 10 (IP-10) expression. As IP-10 is the major product of type-1 IFN pathway downstream of TLR4, we then infused recombinant IFN-beta (rIFN-beta) directly into mouse livers. Interestingly, infusion of rIFN-beta upregulated hepatic IP-10 expression. In contrast, adjunctive CoPP treatment decreased IP-10 levels in mouse livers infused with rIFN-beta. Thus, CoPP-induced HO-1 upregulation suppresses type-1 IFN pathway downstream of TLR4 system in hepatic warm I/R injury model.

Animals↗
PubMed2005

Ischemia and reperfusion injury in liver transplantation.

Ischemia/reperfusion (I/R) injury is a multifactorial process detrimental to liver graft function. An understanding of the mechanisms involved in I/R injury is essential for the design of therapeutic strategies to improve the outcome of liver transplantation. The generation of reactive oxygen species subsequent to reoxygenation inflicts tissue damage and initiates a cellular cascade leading to inflammation, cell death, and ultimate organ failure. The accruing evidence suggests that Kupffer cells and T cells mediate the activation of neutrophil inflammatory responses. Activated neutrophils infiltrate the injured liver in parallel with increased expression of adhesion molecules on endothelial cells. The heme oxygenase (HO) system is among the most critical of the cytoprotective mechanisms activated during the cellular stress, exerting anti-oxidant and anti-inflammatory functions, modulating the cell cycle, and maintaining the microcirculation. The activation of toll-like receptors (TLR) on Kupffer cells may provide the triggering signal for pro-inflammatory responses in the I/R injury sequence. Indeed, dissecting TLR downstream signaling pathways plays a fundamental role in exploring novel therapeutic strategies based on the concept that hepatic I/R injury represents a case for host "innate" immunity.

Humans↗
PubMed2005

Identification of early tolerance regulator genes induced by allochimeric therapy using microarray-based genomewide scan.

We have demonstrated that peri- or postoperative delivery of allochimeric [a1h(u)]-RT1.A(a) class I major histocompatibility complex molecules with donor-type (RT1A(u)) immunogenic epitopes presented in recipient-type (RT1A(a)) sequences induced donor-specific tolerance in ACI (RT1a) recipients of WF (RT1u) heart allografts. A genomic scan during the early posttransplant period was performed to elucidate the underlying operative mechanisms. A rat genome study after transplantation was carefully designed using Affymetrix Rat Genome 230 2.0 Array. The allochimeric treatment group is 3-day cyclosporine (CsA)-treated ACI recipients that accepted Wistar Furth RT1u cardiac allografts with postoperative dosage of allochimeric molecules, while the control is 3-day CsA-treated ACI recipients of WF cardiac allografts. All the samples were harvested 5 days after heart transplant as the early stage of tolerance detection. Following array data normalization and modeling, we compared the above two treatment groups and identified a total of 250 tolerance regulator genes induced by allochimeric molecules only.

Animals↗
PubMed2005

Gene therapy for the prevention of ischemia/reperfusion injury in organ transplantation.

Introduction of gene therapy into molecular medicine has been gaining increasing interest. Although treatment of various diseases e.g. monogenetic defects or cancer by using gene transfer technologies has been extensively probed, the clinical success has been limited. However, recent experimental data suggest that gene therapy may represent an attractive and powerful approach in preventing ischemia/reperfusion injury as well as organ rejection in transplant recipients. Easy and selective access to the donor organ facilitates the reduction of potentially harmful systemic side effects of gene therapy vectors. By introducing anti-apoptotic or cytoprotective genes, these studies focused on the protection of the transplant from the apoptotic cell death. In addition, down-regulation of adhesion molecules and/or blockade of gene expression in the graft itself also ameliorated ischemia/reperfusion injury. This review summarizes the current progress on gene therapy application in combating ischemia-reperfusion injury in organ transplantation. Although the use of viral vectors is emphasized, non-viral gene transfer techniques are also discussed. Future development of novel, low-immunogenic vectors should further contribute to the minimization of ischemia/reperfusion injury, and thus to the overall success of organ transplantation.

Adenoviridae↗
PubMed2004

P-selectin knockout mice have improved outcomes with both warm ischemia and small bowel transplantation.

AIM: To analyze the role of P-selectin in intestinal ischemia and reperfusion injury (IRI) using murine models. METHODS: A model of warm IRI wherein the SMA was occluded for 100 minutes was undertaken in the following groups (10 mice per group): Group 1 (control) wild-type (WT) C57BL6, no treatment; Group 2: 0.4 mg/kg of r-PSGL1-lg 10 minutes before and after clamping; Group 3: PSGL KO mice. Survival was assessed at 7 days; the intestine was assayed for histopathology, apoptosis, myeloperoxidase (MPO), IL1, and TNF. A second model of cold IRI followed by intestinal transplantation (IT) was undertaken in the following groups (two mice per group): Group A WT --> WT: Group B PSGL KO --> WT (1-hour ischemia); Group C: PSGL KO --> WT (2 hour ischemia). Survival only was assessed. RESULTS: Survival was 50% in group 1, 90% in group 2, and 100% in group 3. Graded histopathology and crypt apoptosis demonstrated significantly less injury in groups B and C. MPO was not different between groups. IL1 and TNF were significantly reduce in groups 2 and 3. Following IT, survival was <12 hours in group A, >7 days in group B, and <72 hours in group C. CONCLUSION: This study clearly demonstrates the importance of P-selectin in warm and cold IRI in that the blockade of P-selectin using rPSGL1-lg or the absence of P-selectin using KO mice confers a survival advantage and reduction in tissue injury. The mechanism is unclear but appears to be independent of neutrophil infiltration.

Animals↗
PubMed2003

Heavy chain ferritin acts as an antiapoptotic gene that protects livers from ischemia reperfusion injury.

Heme oxygenase-1 (HO-1) is induced under a variety of pro-oxidant conditions such as those associated with ischemia-reperfusion injury (IRI) of transplanted organs. HO-1 cleaves the heme porphyrin ring releasing Fe2+, which induces the expression of the Fe2+ sequestering protein ferritin. By limiting the ability of Fe2+ to participate in the generation of free radicals through the Fenton reaction, ferritin acts as an anti-oxidant. We have previously shown that HO-1 protects transplanted organs from IRI. We have linked this protective effect with the anti-apoptotic action of HO-1. Whether the iron-binding properties of ferritin contributed to the protective effect of HO-1 was not clear. We now report that recombinant adenovirus mediated overexpression of the ferritin heavy chain (H-ferritin) gene protects rat livers from IRI and prevents hepatocellular damage upon transplantation into syngeneic recipients. The protective effect of H-ferritin is associated with the inhibition of endothelial cell and hepatocyte apoptosis in vivo. H-ferritin protects cultured endothelial cells from apoptosis induced by a variety of stimuli. These findings unveil the anti-apoptotic function of H-ferritin and suggest that H-ferritin can be used in a therapeutic manner to prevent liver IRI and thus maximize the organ donor pool used for transplantation.

Adenoviridae↗
PubMed2003

Biliverdin protects rat livers from ischemia/reperfusion injury.

OBJECTIVE: To explore putative cytoprotective functions of biliverdin during hepatic ischemia/reperfusion (I/R) injury in rat models. MATERIAL AND METHODS: Male Sprague Dawley (SD) rat livers were harvested and stored for 24 hours at 4 degrees C in University of Wisconsin (UW) solution (n=18), and then perfused with blood for 2 hours on an isolated rat liver perfusion apparatus equipped for temperature (37 degrees C), pressure (13 cm H2O), and pH (7.3) maintenance. Biliverdin was added to the blood at concentrations of 10 and 50 micromol in two groups of six animals. Portal vein blood flow, bile production, and GOT/GPT levels were assessed serially. At the conclusion of the experiment, liver samples were collected for histologic evaluation using Suzuki criteria. RESULTS: BV exerted protective effects against liver I/R injury. Adjunctive biliverdin improved portal venous blood flow (mL/min/g) from the beginning of reperfusion (1.33+/-0.17 versus 0.98+/-0.15; P<.001) and increased bile production (mL/g) as compared with the control group (3.40 versus 1.88; P<.003). I/R-induced hepatocellular damage as measured by GOT/GPT release (IU/L) was diminished in the biliverdin group (91 versus 171 and 46 versus 144, respectively; P<.0001). Improved liver function by biliverdin was accompanied by preservation of the histologic structure as assessed by Suzuki criteria (3.7+/-1.4 versus 6.8+/-0.8 in untreated controls; P<.005). CONCLUSIONS: Biliverdin attenuates the ischemia/early reperfusion injury of rat liver grafts as assessed by hemodynamics, function, enzyme analysis, and histology. This study provides the rationale for novel therapeutic approaches using biliverdin to maximize the organ donor pool through the safer use of liver transplants despite prolonged periods of cold ischemia.

Alanine Transaminase↗
PubMed2001

T cell subsets and in vitro immune regulation in "infectious" transplantation tolerance.

CD4-targeted mAb therapy results in permanent acceptance of cardiac allografts in rat recipients, in conjunction with features of the infectious tolerance pathway. Although CD4(+) T cells play a central role, the actual cellular and molecular tolerogenic mechanisms remain elusive. This study was designed to analyze in vitro alloimmune responses of T lymphocytes from CD4 mAb-treated engrafted hosts. Spleen, but not lymph node, cells lost proliferative response against donor alloantigen in MLR and suppressed test allograft rejection in adoptive transfer studies, suggesting compartmentalization of tolerogenic T cells in transplant recipients. A high dose of exogenous IL-2 restored the allogeneic response of tolerogenic T cells, indicating anergy as a putative mechanism. Vigorous proliferation of the tolerogenic T cells in in vivo MLR supports the existence of alloreactive lymphocytes in tolerogenic T cell repertoire and implies an active operational suppression mechanism. The tolerogenic splenocytes suppressed proliferation of naive splenocytes in vitro, consistent with their in vivo property of dominant immune regulation. Finally, CD45RC(+) but not CD45RC(-) T cells from tolerant hosts were hyporesponsive to alloantigen and suppressed the proliferation of normal T cells in the coculture assay. Thus, nondeletional, anergy-like regulatory mechanisms may operate via CD4(+)CD45RC(+) T cells in the infectious tolerance pathway in transplant recipients.

Animals↗
PubMed2001

Allochimeric class I MHC molecules prevent chronic rejection and attenuate alloantibody responses.

BACKGROUND: We have shown that treatment with molecularly engineered, allochimeric [alpha1 hl/u]-RT1.Aa class I MHC antigens bearing donor-type Wistar-Furth (WF, RT1.Au) amino acid substitutions for host-type ACI (RTI.Aa) sequences in the alpha1-helical region induces donor-specific tolerance to cardiac allografts in rat recipients. This study examined the effect of allochimeric molecules on the development of chronic rejection. METHODS: Allochimeric [alpha1 hl/u]-RT1.Aa class I MHC antigenic extracts (1 mg) were administered via the portal vein into ACI recipients of WF hearts on the day of transplantation in conjunction with subtherapeutic oral cyclosporine (CsA, 10 mg/kg/day, days 0-2). Control groups included recipients of syngeneic grafts and ACI recipients of WF heart allografts treated with high-dose CsA (10 mg/kg/day, days 0-6). RESULTS: WF hearts in ACI rats receiving 7 days of CsA exhibited myocardial fibrosis, perivascular inflammation, and intimal hyperplasia at day 80. At day 120, these grafts displayed severe chronic rejection with global architectural disorganization, ventricular fibrosis, intimal hyperplasia, and progressive luminal narrowing. In contrast, WF hearts in rats treated with [alpha1 hl/u]-RT1.Aa molecules revealed only mild perivascular fibrosis, minimal intimal thickening, and preserved myocardial architecture. Alloantibody analysis demonstrated no IgM alloantibodies in all groups. An attenuated, but detectable, anti-WF IgG response was present in recipients receiving allochimeric molecules, with IgG1 and IgG2a subclasses predominating. Immunohistochemical analysis of allografts demonstrated minimal T cell infiltration and IgG binding to vascular endothelium. CONCLUSION: Treatment with allochimeric molecules prevents the development of chronic rejection. Such effect may be in part caused by deviation of host alloantibody responses.

Amino Acid Sequence↗
PubMed2001

Evidence of T cell clonality in the infectious tolerance pathway: implications toward identification of regulatory T cells.

We have shown that a rare population of regulatory CD4+ T cells plays a key role in the acquisition of infectious tolerance in rat sensitized recipients of cardiac allografts pretreated with nondepleting anti-CD4 mAb. This study was designed to analyze the TCR Vbeta expression patterns in this transplantation model. First, we used Vbeta-specific RT-PCR to show that there was no differential usage of TCR Vbeta genes by T cells mediating rejection or tolerance. Indeed, graft-infiltrating lymphocytes expressed most of the 22 known rat TCR Vbeta genes in both recipient groups, suggesting unrestricted TCR Vbeta repertoire in alloreactive T cells. Then, we applied CDR3 spectrotyping of TCR beta-chain to assess the clonality of T cells at different anatomic sites. CDR3 size restriction, indicative of the presence of T cell clones, was observed in graft-infiltrating lymphocytes but not in draining lymph nodes or spleen of tolerant hosts. Consisent with the clonal expansion, T cells in tolerated grafts exhibited the memory phenotype at a much higher percentage as compared with peripheral lymphoid organs. Moreover, in tolerated graft-infiltrating lymphocytes, the CD3 size restriction occurred in limited Vbeta gene families, with Vbeta8.1 and Vbeta18 most frequently detected. Hence, T cells at the graft site of tolerant recipients contain T cell clones expressing selective Vbeta genes. This phenotypic characteristics of the tolerogenic GILs may potentially be used as a novel marker to identify operational regulatory T cells in organ allograft recipients.

Animals↗