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C E Haisch

Publications and source records attributed to C E Haisch.

At least 19 recordsLinked to original sources
PubMed2001

Human T-cell-porcine endothelial cell interactions induce human Th1 cytokines and porcine activation markers.

BACKGROUND: Since the future of clinical transplantation will undoubtedly include xenotransplantation, there is a need to examine human anti-pig cellular reactions. The objective of this study is to use human anti-porcine mixed lymphocyte endothelial cell culture (MLEC) to investigate cell interactions, cross-species molecular compatibilities, and the induction of human cytokines and porcine activation markers. METHODS: Human peripheral blood mononuclear cells or enriched CD4+ T cells depleted of professional antigen-presenting cells were cultured with resting pig aortic endothelial cells in the absence of exogenous cytokines. T-cell proliferative responses were measured and PAEC were monitored for cell surface markers by flow cytometry. Culture supernatants were assayed for human TNF-alpha and IFN-gamma by ELISA. RESULTS: Human T cells proliferated strongly in response to PAEC (median stimulation index = 75), even in serum-free cultures. High levels of the human Th1 cytokines TNF-alpha (20-350 pg/ml) and IFN-gamma (200-3800 pg/ml) were detected only in cultures containing PAEC, with levels peaking on Day 4. CD4+ T-cell-enriched, APC-depleted responders maintained proliferative anti-PAEC responses and cytokine release. By Day 3, MHC Class II and VCAM expression was induced in 92-96% PAEC: mean fluorescence intensity (MFI) increased from 5 to 83 +/- 12 and 166 +/- 74, respectively, and MHC Class I was increased from MFI 31 to 965 +/- 269. CONCLUSIONS: These results indicate that MLEC is an excellent in vitro model in which to study human anti-porcine cellular responses. Human T cells are activated in response to direct antigen presentation by PAEC, which are also activated in this system. Specific cytokines, receptors, and adhesion molecules appear to cross the xenograft barrier and play a critical role in T-cell - PAEC interactions. Such interactions are likely to affect VEC activation and immune responses to porcine xenografts in vivo.

Animals↗
PubMed2001

Pretransplantation prognostic testing on damaged kidneys during ex vivo warm perfusion.

BACKGROUND: Further expansion of the donor pool with ischemically damaged kidneys will be predicated on the ability to develop prognostic testing. Using a well-established canine autotransplantation injury model, we assessed whether actual restoration of renal metabolism by ex vivo warm perfusion could be used to predict the status of an organ before transplantation. METHODS: Kidneys were subjected to 30 min of warm ischemia followed by 24 hr of static storage in ViaSpan at 4 degrees C. After warm ischemia and static storage the kidneys were transitioned to 3 hr of warm perfusion using Exsanguinous Metabolic Support technology. During this period, parameters indicative of renal metabolism and vascular function were used to predict outcomes prospectively. Parameters included measures of oxidative metabolism, perfusion characteristics, and vascular condition. A Viability Score (VS) was calculated as the sum of the three parameters mentioned above. Results were grouped by a VS>2 and a VS<2. RESULTS: A clear association between the severity and duration of graft dysfunction and the VS was observed. Organs with a VS>2 had a significantly milder period of acute tubular necrosis, with both a less severe rise in serum creatinine (mean of 4.4 vs. 11 mg/dl) and a shorter recovery period (mean of 8 vs. 18 days) than those with a VS<2. CONCLUSIONS: Results indicate the possibility of utilizing warm perfusion to evaluate kidneys before transplantation. The VS developed demonstrated efficacy in classifying the severity of the acute tubular necrosis and the occurrence of primary nonfunction, offering a sensitive assay for prospective organ testing.

Animals↗
PubMed2001

Deletrious effect of prolonged cold ischemia on renal function.

The detrimental effect of prolonged cold ischemia (CI) on posttransplant renal function has long been recognized. However, the cellular consequences of CI have not been clearly defined. This study describes a model for the identification of CI-induced injury by evaluating ex-vivo renal metabolism and function prior to reperfusion. Small bovine kidneys were cold stored in Viaspan for 24-, 48-, 72-, and 96 h. Kidneys were then warm perfused (32 degrees C) using Exsangiunous Metabolic Support (EMS) technology and evaluated for oxidative metabolism, vascular dynamics and function. Oxygen consumption, vascular resistance, and diuresis were stable in kidneys with CI up to 48 h. After 72- and 96 h of CI, vascular resistance was increased while oxygen consumption and diuresis were reduced (P < 0.05). Glomerular filtration rate was diminished at CI greater than 24 h (P < 0.05). Results show that function was compromised with CI greater than 24 h and preceded the loss of cell viability following 48 h of CI.

Animals↗
PubMed2000

Exsanguinous metabolic support perfusion--a new strategy to improve graft function after kidney transplantation.

BACKGROUND: The compounding damage of warm ischemia (WI) followed by cold preservation is a major barrier in renal transplantation. Although the relative effect of WI is not yet well understood, therapeutic strategies have mostly focused on minimizing the pathology seen upon reperfusion from the cold. Our study was designed to examine the effect of restoration of renal metabolism by warm perfusion on graft survival and to investigate the compounding damage of WI. METHODS: Using a known critical canine autotransplantation model (1), kidneys were exposed to 30 min WI followed by 24 hr cold storage in Viaspan. They were then either reimplanted directly or first transitioned to 3 hr of warm perfusion with an acellular perfusate before reimplantation. Contralateral kidneys were subjected to 0, 30, or 60 min WI; 24 hr cold storage, and 3 hr warm perfusion. RESULTS: Transplanted kidneys that were warm perfused before reimplantation had both lower 24 hr posttransplant serum creatinine (median of 3.2 vs. 4.1 mg/dl) and lower peak serum creatinine (median of 4.95 vs. 7.1 mg/dl). Survival rate for warm perfused kidneys was 90% (9/10) vs. 73% (8/11). In the contralateral kidneys, metabolism was affected by the compounding damage of WI. Renal oxygen and glucose consumption diminished significantly, whereas vascular resistance and lactate dehydrogenase-release rose significantly with increasing WI. CONCLUSIONS: The results demonstrate a reduction of reperfusion damage by an acellular ex vivo restoration of renal metabolism. Furthermore, data from the contralateral kidneys substantiates the relative role of WI on metabolism in renal transplantation.

Animals↗
PubMed1997

Preclinical studies of allograft tolerance in rhesus monkeys: a novel anti-CD3-immunotoxin given peritransplant with donor bone marrow induces operational tolerance to kidney allografts.

A major challenge in clinical transplantation today is to design a practical and effective protocol for tolerance induction compatible with cadaver organ transplantation. A preclinical rhesus monkey kidney allograft model using immediate peritransplant anti-CD3 immunotoxin (anti-CD3-IT) and donor bone marrow (DBM) is shown here to induce operational tolerance with prolonged graft survival in the absence of chronic immunosuppressive drugs. Bone marrow harvested from the kidney donor was depleted of mature alloantigen-presenting cells and T cells by removing DR(bright) cells and CD3(bright) cells, respectively. In outbred, major histocompatibility complex-incompatible donor-recipient pairs with high pretransplant mixed lymphocyte response and cytotoxic T lymphocyte precursor activity, four of six allografts survived for periods of 120 days to >1.5 years. Graft acceptance after peritransplant treatment followed robust elimination of both peripheral blood T cells and lymph node T cells. In most recipients given anti-CD3-IT and DBM infusion, anti-donor immunoglobulin G responses were completely inhibited. Microchimerism was observed in all recipients studied, including those not given DBM, but levels of microchimerism did not correlate with graft survival. Anti-CD3-IT induction in combination with modified DBM protocols such as the depletion of mature T cells and DR(bright) antigen-presenting cells may offer new opportunities to improve clinical tolerance protocols beyond those attempted in the clinic to date. Overall, these results with anti-CD3-IT show promise for development of cadaver transplant tolerance induction.

Animals↗
PubMed1995

The facilitating effect of one-DR antigen sharing in renal allograft tolerance induced by donor bone marrow in rhesus monkeys.

Infusion of donor bone marrow cells (DBMC), a long-standing, successful strategy for inducing tolerance in experimental rodent transplantation models, can promote long-term acceptance of life-sustaining renal allografts in rhesus monkeys with no maintenance immunosuppression. To investigate the immunological basis for heterogeneity in duration of long-term graft acceptance following infusion of the DR-/dim fraction of DBMC into RATG-treated rhesus monkeys, we examined the relationship of recipient-donor major histo-compatibility class I and II DR matching to the development of antidonor antibody-dependent cellular cytotoxicity (ADCC) and renal allograft survival. The findings indicate a requirement for sharing one DR allele to achieve long-term graft acceptance. The observed immunological consequence of DR sharing that correlated with functional graft tolerance in this model was the suppression of early antidonor ADCC+ IgG antibody responses. Significant associations were observed between graft survival and suppression of ADCC antibody (P < 0.0005), graft survival and DR sharing (P < 0.005), and DR sharing and suppression of ADCC (P < 0.02). Early antidonor ADCC antibody responses associated with failure to maintain graft tolerance and were most consistently directed to donor class I. The required one DR antigen sharing in DBMC-induced suppression of antidonor class I antibody suggests a restriction for recipient DR, implying critical regulation of a response to donor antigen presented on recipient cells. We hypothesize a DBMC tolerogenic mechanism in which presentation of donor class I peptide by a shared DR allele configuration allows a veto effect by DBMC. Thus DR sharing would allow DBMC veto cells to reduce clonal expansion elicited by both the direct and indirect antigen presentation pathways.

Animals↗
PubMed1994

A role for transforming growth factor-beta in the veto mechanism in transplant tolerance.

We have studied the veto cell-mediated induction of transplant tolerance by allogeneic donor bone marrow cells and have achieved kidney allograft tolerance in a preclinical rhesus monkey model. Here we extend these studies to investigate the veto mechanism of CTLp suppression and the role of CD8 and TGF-beta in these events. Infusion of DR-/dim donor BMC into RATG-treated rhesus monkeys induced functional deletion of donor-specific CTLp and prolongation of kidney allograft survival, whereas depletion of the CD8+ subset from BMC ablated these effects. A role of CD8 in the veto effect was further implicated by rhesus MLR-induced CML experiments in which pretreatment of normal responder cells with MAb to MHC class I, the natural ligand of CD8, blocked the suppressive activity of allogeneic BMC. In addition, pretreatment of the BMC with anti-CD8 MAbs blocked strong veto activity significantly, suggesting that CD8 functions as an accessory or adhesion ligand. In contrast, anti-CD8 treatment significantly enhanced weak BMC-mediated veto activity, suggesting that CD8 might additionally serve as a signal transducer to increase veto activity, perhaps by the induction of cytokine release. The cytokine TGF-beta was studied because it has immunosuppressive properties that are shared by veto cells. Human TGF-beta, like BMC veto cells, inhibited MLR-induced CML in a dose-dependent manner, and anti-TFB-beta Ig relieved the BMC-mediated veto suppressive effect. Active TGF-beta was detected only in the supernatants of CML cultures containing BMC. Pretreatment of BMC with L-leucyl-leucine methyl ester (Leu-leu-OMe), which eliminates cytotoxic precursor and effector lymphocytes and monocytes, did not affect levels of active TGF-beta. In previous studies, the veto effect of BMC was also shown to be Leu-leu-OMe-resistant. Finally, treatment of isolated DR-/dim BMC cultures with anti-CD8 elicited TGF-beta secretion, whereas anti-CD2 or anti-CD3 had no effect. When isolated after stimulation with anti-CD8, only the CD8+ subset of DR-/dim BMC produced detectable levels of active TGF-beta. In summary, these studies demonstrate that CD8 functions as an immunoregulatory molecule in veto effects by freshly isolated rhesus BMC and suggest that CD8-ligand interactions may induce low-level secretion of TGF-beta to mediate or facilitate the veto mechanism of CTLp inactivation in a paracrine manner.

Animals↗
PubMed1994

Further studies of veto activity in rhesus monkey bone marrow in relation to allograft tolerance and chimerism.

Infusing the DR-/dim fraction of bone marrow cells (BMC) from an allogeneic kidney donor into rabbit antithymocyte globulin-treated transplant recipients delivers a tolerogenic signal, leading to functional allograft tolerance in rhesus monkeys without additional drug therapy. Our updated results in an expanded series show a median 131-day graft survival of recipients given DR-/dim donor BMC with a 23% 1-year survival (P < 0.00001 vs. rabbit antithymocyte globulin controls). Removing DRbright cells from donor BMC appeared to have a significant effect (P < 0.05). We have further investigated the tolerogenic mechanism within the experimental framework of the veto hypothesis in this preclinical model. In limiting dilution assays, we demonstrated the donor specificity of clonal inactivation of CTL precursors (CTLp) after in vitro or in vivo exposure to DR-/dim donor BMC, confirming specific tolerance. Additionally, in vitro studies confirmed the allogeneic specificity of CTLp inactivation in 3-cell MLR assays; minimal bystander effects were seen on normal CTLp responses to third party stimulator cells, while CTLp responses to the BMC donor's cells were abrogated in the same cultures. BMC mediating the veto effect were found to be resistant to L-leucyl-L-leucine methyl ester (Leu-leu-OMe), which excluded BMC-mediated cytotoxicity by NK or lymphokine-activated killer cells, CTL, or activated macrophages. In contrast, veto activity was abolished if the BMC were pretreated with either high dose UV-B light irradiation, mitomycin, or gamma-irradiation, indicating that BMC contained a UV-B-sensitive precursor of the veto effector, and that a proliferative step separated the two. Irradiation of DR-/dim donor BMC or administration of cyclophosphamide after infusion of nonirradiated BMC prevented the tolerogenic effect. Only recipients given nonirradiated DR-/dim donor BMC demonstrated PBL chimerism, which associated with functional deletion of antidonor CTLp and duration of graft survival. The Leu-leu-OMe resistance and the other properties of the allogeneic monkey CD3- CD2+ CD8+ BMC subpopulation that exhibits tolerance-promoting activity in vitro and in vivo lead us to postulate that a donor BMC-derived precursor population, possibly a dendritic cell population, may induce allogeneic unresponsiveness in this model.

Animals↗
PubMed1994

Veto cells in transplantation tolerance.

Advances in immunosuppressive management for transplantation have improved graft survival. However, lasting success will probably depend on the induction of donor-specific unresponsiveness, avoiding chronic immunosuppressive drug therapy and its debilitating side effects. Tolerance strategies have been developed in rodents, but applicability to human organ transplantation has not been achieved. We have established a preclinical allogeneic kidney transplant model in unrelated outbred rhesus monkeys and have investigated a tolerance-inducing strategy in which posttransplant administration of rabbit antithymocyte globulin and infusion of a subpopulation of donor bone marrow cells yields long-term graft acceptance in the absence of chronic immunosuppressive drugs. Recent studies of the immunological mechanisms by which induction and maintenance of transplant tolerance is achieved in this model are presented within the framework of a veto hypothesis.

Animals↗
PubMed1993

15-Deoxyspergualin: a novel immunosuppressive drug with clinical potential.

The studies discussed in this review suggest that DSG is a potent immunosuppressive agent, with at least some of its activity due to its direct effects on macrophages and B cells. The effects of DSG on macrophages include inhibition of IL-1, chemiluminescence, expression of MHC Class I antigen on the surface, and development of MAF. The agent may well interfere with antigen processing and the discovery of its binding to the heat-shock protein 70 may shed some light on this area. The effects of DSG on B lymphocytes include inhibition of surface Ig expression and B cell differentiation. In addition, however, DSG exhibits some effects on both B and T lymphocytes and is markedly active in blocking both the primary and secondary cytotoxic T cell and antibody-producing cell generation. The agent is relatively nontoxic at the doses in which it exerts these marked effects. Thus, an overall assessment of DSG shows that it may provide immune suppression at levels different from those of immunosuppressive agents already available. Advances in human organ transplantation have for the most part occurred stepwise with the introduction of progressively improved techniques of immunosuppression. Tissue-matching, organ preservation, techniques of transplantation, and surgical post-operative care of organ transplant recipients have all improved over the 30 years since organ transplantation began, but have not been the major factors in the improved survival of both patients and grafts seen at the present time. The initial advance in immunosuppression which made the first organ transplants possible was the finding of the immunosuppressive capabilities of azathioprine (Imuran) and the ability to reverse acute rejection crisis with prednisone. Anti-thymocyte or anti-lymphocyte globulin, introduced in 1966, achieved variable results, with some groups reporting excellent patient and graft survival using this agent. Others using different variations of this drug showed no improvement in results. By the mid-1970s, transplant results had improved at a number of units, with graft survivals of kidney and heart recipients in the 70 percent range at 1 to 2 years. No major progress was reported in most units, however, until the introduction in 1978 of cyclosporine. A major effect of cyclosporine was to create a universal improvement in graft survival in all units surveyed around the world with a 70 to 75 percent one-year cadaver kidney graft survival, representing the basic standard for clinical results.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Potential availability of transplantable organs and tissues in fatalities from injury and nontraumatic intracranial hemorrhage.

Study of all Vermont and urban Rhode Island trauma fatalities for 1987, and all fatalities in these states from nontraumatic intracranial hemorrhage for 1986 and 1987, identified few potential donors for asystole-sensitive organs, such as heart, lungs, liver, pancreas, and kidneys. It is estimated that nationally there is a maximum potential of about 5000 cadavers per year from these two sources that meet screening criteria for age, duration of survival after event, brain death, and absence of organ damage or important disease. This would yield up to 5000 hearts, livers, and pancreases, perhaps 5-6000 lungs, and up to 10,000 kidneys. However, for tissues that have longer postdeath viability it is estimated that annually at least 60,000 eyes, 22,000 heart valve sets, 29,000 donations of 2 or more long bones per cadaver, and 36,000 skin donations are potentially available from these sources.

Accidents, Traffic↗
PubMed1993

T cell subset responses to allogeneic endothelium. Proliferation of CD8+ but not CD4+ lymphocytes.

Endothelial cells were isolated from the hearts of neonatal mice and cocultured with syngeneic and allogeneic lymphocytes. T cells isolated by passage through nylon wool proliferated when cultured with allogeneic endothelium but not when cultured with syngeneic endothelium. This response was almost entirely confined to the CD8+ lymphocyte subset as purified CD4+ lymphocytes displayed a minimal response. Pretreatment of endothelial cells with recombinant murine gamma interferon induced expression of Ia but did not enable endothelial cells to activate CD4+ lymphocytes. Activation of CD8+ and T lymphocytes could be blocked with monoclonal anti class I antibody but was unaffected by anti-class II antibody. The failure to activate CD4+ lymphocytes was not due to suppression and did not lead to an anergic state. Instead, coculture of CD4+ cells with allogeneic endothelial cells induced a partial activation consisting of IL-2 receptor expression and accelerated secondary response kinetics.

Animals↗
PubMed1992

Potential availability of transplantable organs according to factors associated with type of injury event.

Potential availability of transplantable organs from different types of injury fatalities was studied. Factors examined included target organ damage or disease, age of potential donor, duration of survival before circulatory arrest, and universal rejection factors such as sepsis, HIV infection, or systemic malignancy. Motor vehicle fatalities yielded the greatest proportion of potentially viable organs. Delay in discovery and universal rejection factors were important exclusionary issues for fatalities from suicide, homicide, and non-motor vehicle unintentional injury. There was no difference in organ damage or in duration of survival with higher speeds in fatal crashes, suggesting that states with 65 mph speed limits--and consequently higher death rates--may have greater potential availability of donatable organs than do those with 55 mph maximum. The increase in deaths at higher speeds, however, vastly outweighs the benefits of any possible increase in the potential for donor organs.

Accidents, Traffic↗