Development Of Graft Vascular Disease Research Articles

Abstract 458: Role of Colony Stimulating Factor 1 Receptor in Graft Vascular Disease

Heart and kidney transplants are effective treatments for end-stage organ failure, but their long-term success is limited by graft vascular disease (GVD), the leading cause of solid organ transplant failure. This process manifests as concentric thickening of vessel walls due to neointimal hyperplasia in the donor organ, characterized by expansion of cells, notably smooth muscle-like cells (SMLCs) and macrophages (MPs), which accumulate, proliferate, and eventually occlude the lumen of arteries. Our lab recently reported that loss of colony stimulating factor-1 (CSF1) expression in either donor or recipient mice limits GVD, and showed that SMLCs isolated from neointimal lesions express high levels of CSF1 and its receptor, CSF1R. While CSF1-mediated activation of CSF1R has been studied extensively in MP biology, its role in SMLCs and GVD has not been well characterized. We hypothesize that CSF1R activation in neointimal MPs and SMCs occurs after organ transplantation and promotes the development of GVD. To test this idea, carotid arteries from 8-12 week old C57/B6J male mice were transplanted orthotopically into female or male mice. At day 30 post transplantation, sex-mismatched transplants developed significant neointimal lesions not seen in sex-matched controls. Neointimal, adventitial, and to a lesser extent medial cells were positive for CSF1R and CD68, which were scarcely detected in control untransplanted arteries. Cells in the media of transplanted vessels co-stained for smooth muscle alpha actin (SMA) and calponin. SMA-positive cells were found in neointimal lesions, with few cells co-expressing calponin. Proliferation, assessed by Phospho-histone H3 staining, was evident in cells of uncertain origin in the media and neointima. In conclusion, H-Y antigen-driven histoincompatibility in this mouse transplant model yielded vascular lesions that resemble GVD, with significant neointima formation, preservation of medial cells, and evidence of CSF1R expression and of cell proliferation. Future studies will focus on lineage tracing of smooth muscle and myeloid cells to evaluate neointimal cell origins, plus genetic depletion of CSF1R in these cell lineages to determine the requirement for CSF1R expression in the development of GVD.

Análisis de supervivientes a los 8 años del trasplante cardiaco: un estudio caso-control

IntroductionLong-term survival predictors after Heart Transplantation (HT) have not been fully established. We intend to identify 8-year mortality predictors after HT. MethodsFrom an unicentric, prospective cohort of 276 HT patients (recruited from 1991 to 2007), characteristics of survivors (cases) vs. those who died (controls) 8 years after HT were compared. Mortality predictors were identified using a multivariate logistic regression analysis. ResultsThere were 119 survivors and 157 controls. 8-year mortality predictors in the multivariate model were receptor age (OR=1.03; 95% CI: 1.00-1.06; P=.05), functional class IV NYHA at the moment of HT (OR=3.57; 95% CI: 1.00-12.73; P=.05), and need for dialysis after HT (OR=7.21; 95% CI: 1.41-37.02; P=.02). ConclusionsIn our cohort, increased receptor age, functional class IV NYHA at the moment of HT, and need for dialysis after HT were independent predictors of 8-year mortality. Cytomegalovirus infection, development of graft vascular disease or hypertension after HT were independently associated to long-term survival.

Adiponectin and Graft Vascular Disease After Cardiac Transplantation

Graft vascular disease (GVD) is a form of accelerated atherosclerosis that involves the transplanted heart, affecting more than 40% of patients after follow-up of 5 years. According to some authors, adiponectin concentration is a prognostic factor for progression of coronary atherosclerosis. Following this line of research, the objective of the present study was to analyze the relationship between adiponectin concentration and development of GVD in 52 cardiac transplant recipients. Patients were divided into 2 groups according to findings at intravascular ultrasound: group 1 with 21 patients without GVD, and group 2 with 31 patients with GVD. Patients with GVD were further divided into 2 additional groups according to results of coronary angiography: group 3 with 35 patients without GVD, and group 4 with 17 patients with any degree of GVD. No significant differences ( P = .50) were observed insofar as adiponectin concentration between groups 1 and 2, and groups 3 and 4. Significant differences in adiponectin concentration were observed when the sex of the patient was considered ( P = .002), with higher concentrations detected in women. Serious cardiac events were more common in patients with GVD ( P = .001). Mean time between transplantation and diagnosis of GVD was 67 months in group 1, 107 months in group 2, 71 months in group 3, and 101 months in group 4. Significant differences were observed between groups 1 and 2 ( P = .030).

Microvascular rarefaction

The goals of this presentation are two-fold: (1) to briefly sketch the field of vascular rarefaction as a key component of various fibrotic diseases and (2) to illustrate it with four vignettes depicting diverse mechanisms of microvascular rarefaction. Specifically, I shall describe migratory and angiogenic incompetence of endothelial cells under conditions of reduced bioavailability of nitric oxide, role of endothelial-to-mesenchymal cell and mesenchymal stem cell-to-endothelial reprogramming and potential role of antiangiogenic peptides in the development of graft vascular disease as exemplified by chronic allograft nephropathy.

Cytomegalovirus infection after heart transplantation. Retrospective analysis of an antiviral CMV prevention

Cytomegalovirus (CMV) infection is the most common viral infection in the early period after heart transplantation (HTX) and causes a significant morbidity and mortality. Although controversial, CMV is related to acute and chronic allograft rejection and to the development of graft vascular disease. It therefore plays an important role in the long-time outcome after solid organ transplantation. 45 patients received a new heart between 1.1.97 and 31.12.1998. All of them were enrolled postoperatively in three-month antiviral prophylaxis (Cymevene). Only those patients were excluded from prophylaxis who were seronegative for CMV and received hearts from seronegative donors (n = 6). The pp65 antigenaemia assay and the murex hybrid capture CMV DNA assay on peripheral blood as well as the early antigen detection in the urine were used for CMV detection and also for monitoring. A total number of 580 assays were analysed (12.9 assays/patient). 561 tests (96.7%) were negative, 19 (3.3%) were positive. For CMV testing the pp65 antigenemia assay was used in 64.1%, the murex hybrid capture CMV DNA assay in 18.4% and the urine early antigen detection in 17.4%. Three patients (6.7%) developed viraemia during the first 3 postoperative months. Two patients (4.4%) suffered from CMV infection 8 and 9 months after heart transplantation and had to be treated with antiviral agents. Three patients (6.7%) died early after transplantation, but none had a CMV infection. Prevention of CMV disease was successful with three months of antiviral CMV prophylaxis after HTX. Asymptomatic viraemia during the prophylaxis period did not lead to tissue invasive disease. It is possible to carry out rapid CMV detection and CMV monitoring with the commercially available antigenaemia assays.

Graft Vascular Disease After Cardiac Transplantation and Its Relationship to Mean Acute Rejection Score

Graft vascular disease remains a significant source of morbidity and mortality in heart transplant patients. The influence of acute cellular rejection on the development of graft vascular disease is controversial. To determine the relationship between mean acute cellular rejection score and the presence of atherosclerosis or fibrointimal hyperplasia in cardiac allografts at autopsy. This retrospective, autopsy-based study examined 27 heart transplant patients to evaluate for graft vascular disease. A rejection score for each patient was calculated as the average of all the rejection scores determined by endomyocardial biopsy. Gross and histologic examination of the heart was used to divide patients into 3 groups: no coronary artery disease, atherosclerosis, and fibrointimal hyperplasia. Mean rejection scores were calculated for each of these groups for all patients and patients who survived longer than 3 months. Mean rejection scores were compared by an analysis of variance and pairwise t tests. Mean rejection scores demonstrated a trend of increasing value from no coronary disease (0.323) to atherosclerosis (0.569) to fibrointimal hyperplasia (0.835). Only fibrointimal hyperplasia had a significantly higher mean rejection score compared with patients with no coronary disease when examined in all patients (P = .01) and in patients who survived longer than 3 months (P = .049). This study showed that the development of coronary artery fibrointimal hyperplasia, but not atherosclerosis, was significantly related to mean acute rejection score.

Expression patterns of vascular endothelial growth factor in human cardiac allografts: association with rejection.

Vascular endothelial growth factor (VEGF), a major angiogenesis factor, has been found to have proinflammatory properties in vivo in several chronic inflammatory diseases. However, little is known of the expression or function of VEGF in acute and chronic allograft rejection. In a cross-sectional analysis, we evaluated the expression of VEGF by immunohistochemistry in human endomyocardial biopsies (n=101) from 10 cardiac transplant patients. We correlated expression (scores from 0-4) with CD3+ T cell, CD68+ monocyte and macrophage infiltrates, or rejection (International Society of Heart and Lung Transplantation grades 0-4). In addition, we evaluated the temporal patterns of VEGF expression in consecutive biopsies from seven patients (total of 74 biopsies) who were assessed for the development of graft vascular disease (GVD) by intravascular ultrasonography at 1 year posttransplantation. VEGF is expressed in normal human endomyocardial biopsies at low levels and is induced (scores >1) in association with CD3+ T cells (odds ratio [OR], 19.90; P<0.001), CD68+ monocyte and macrophage infiltrates (OR, 8.49; P<0.001), and all grades of acute rejection (OR, 5.4; P<0.001). Increases in VEGF expression were persistent during the first posttransplant year in biopsies from four patients who demonstrated evidence of GVD (mean annual score of 2.3). In contrast, limited expression of VEGF was found in three patients without GVD (mean annual score 1.2). These findings define VEGF as an important proinflammatory cytokine after transplantation and indicate that its expression pattern might identify patients at risk for the development of GVD.

Upregulation of heme oxygenase-1 during the development of accelerated graft vascular disease after clinical heart transplantation

Ischemia induced oxidative stress may not only be important in the early posttransplant period, but also during the development of graft vascular disease (GVD) after heart transplantation. Oxidative stress leads to upregulation of heme oxygenase (HO)-1 as a result of activation of the transcription factor hypoxia inducible factor (HIF)-1 . HO-1 is an antioxidant enzym, with anti-apoptotic properties. It is also described that in vitro HO-1 production is regulated by transforming growth factor (TGF), a cytokine that plays a role in the development of GVD after heart transplantation. We hypothesize that HO-1 is involved in the development of GVD, a condition characterized by unrestrained proliferation of smooth muscle cells. To test this hypothesis, we measured mRNA levels of HIF-1 , HO-1 and TGFin biopsies from patients with (n 14) and without (n 13) signs of acceleratd GVD (at one year) after heart transplantation. We found significantly higher HO-1 and TGFmRNA expression levels in biopsies from patients with GVD (p 0.02 and p 0.04, Mann Whitney, figure). Furthermore, in GVD positive, but not in GVD negative patients, a significant strong correlation was found between HIF-1 and HO-1 (rs 0.92, p 0.0001), between HIF-1 and TGF(rs 0.74, p 0.0026) and between HO-1 and TGF(rs 0.65, p 0.011). Our results show that, in accordance with our hypothesis, HO-1 is involved in the development of GVD after heart transplantation. We suggest that TGFinitiates GVD resulting in ischemic damage and thus in HIF-1 induced production of HO-1. HO-1 prevents apoptosis, allowing smooth muscle cells to proliferate, subsequently leading to intima thickening and accelerated graft vascular disease.

The frequency and avidity of committed cytotoxic T lymphocytes (cCTL) for donor HLA class I and class II antigens and their relation with graft vascular disease.

Cellular immune processes may trigger the development of graft vascular disease (GVD). CD4 and CD8 cytotoxic T lymphocytes that infiltrate the allograft could play a role in the development of GVD. We studied the presence of in vivo primed or committed CTL (cCTL) and their avidity for donor HLA class I and class II antigens in graft-infiltrating lymphocyte cultures propagated from endomyocardial biopsies derived from patients with and without signs of GVD. The fraction of cCTL with high avidity for HLA class I or class II antigens was estimated by the addition of anti-CD8 or anti-CD4 MoAbs to the cytotoxic phase of the limiting dilution analysis. In the first year after transplantation no difference in the frequency of donor-specific class I cCTL between patients with and without GVD was found. Addition of anti-CD8 MoAb revealed that most cultures predominantly consisted of cCTL with low avidity for donor HLA class I antigens, irrespective of the development of GVD at 1 year after transplantation. However, in patients who did not develop GVD, the frequency of cCTL with donor HLA class II specificity was significantly higher than in patients who did develop GVD. The avidity for donor HLA class II antigens was comparable in both groups. A high frequency of donor-specific cCTL for HLA class II antigens seems to be a protective factor against the development of GVD. These cCTL might be cytotoxic for cells involved in GVD development, e.g. activated endothelium and smooth muscle cells of donor origin.

Failure to down-regulate intragraft cytokine mRNA expression shortly after clinical heart transplantation is associated with high incidence of acute rejection

Background: Brain-death, ischemia and reperfusion damage have been implicated as initial factors that lead to a cascade of immunologic events that result in allograft rejection in experimental animals. Cytokines are thought to play a central role in this process. Therefore, we evaluated intragraft cytokine mRNA expression at an early stage after clinical heart transplantation and related these data to ischemia, immunosuppression, and rejection. Methods We sampled endomyocardial biopsies at 30 minutes (EMB 0) and at 1 week (EMB 1) after transplantation from 20 cardiac allograft recipients. Intragraft monocyte chemoattractant protein (MCP-1) and basic fibroblast growth factor (bFGF) mRNA expression levels were quantitatively measured using competitive template Reverse-transcriptase polymerase chain reaction (RT-PCR). Results We measured significantly lower MCP-1 and bFGF mRNA expression levels in EMB 1 compared with EMB 0 (MCP-1, p = 0.006; bFGF, p = 0.019). We found no direct correlation between the cytokine mRNA expression levels in EMB 0 or EMB 1 and ischemic times, induction therapy, or cyclosporine whole-blood trough levels. Patients with a high incidence of acute rejection episodes (>2 in the first year) had higher bFGF mRNA expression levels ( p = 0.009) and comparable MCP-1 mRNA expression levels ( p = 0.378) at 1 week, compared with patients with a lower rejection incidence. The MCP-1 and bFGF mRNA expression levels in the first week were not associated with the development of graft vascular disease in the first year post-transplant. Conclusions We found a significant decrease of intragraft MCP-1 and bFGF mRNA expression levels in the first post-operative week. Patients with a high incidence of acute rejection had higher bFGF mRNA expression levels in their first week biopsy. Therefore, we conclude that patients who fail to down-regulate their bFGF mRNA expression early after transplantation are at higher risk for acute rejection.

Endothelial dysfunction and denudation in rat aortic allografts.

Clinical evidence suggests that early endothelial cell (EC) dysfunction may predict the development of graft vascular disease. We wished to assess the early functional and morphological changes in the graft endothelium in a commonly used animal model of graft vascular disease, the rat aortic interposition allograft model. To assess graft EC function, regulation of vascular tone by ECs was monitored in aortic rings from grafts harvested at various times after transplantation (Tx). EC morphology was assessed by silver staining, which was followed by en face inspection of the luminal side of the grafts. Acetylcholine-induced EC-dependent vasorelaxation was reduced in allografts at post-Tx days 7 and 14, whereas in syngeneic grafts EC-dependent relaxation was unaffected at any time after Tx. In separate grafts collected at the same time points, massive leukocyte adhesion at post-Tx day 7 and EC denudation at days 14 and 28 were evident in allografts but not in syngeneic grafts. At post-Tx day 56 (a time at which vessel wall remodeling is pronounced in this model), an intact EC layer covered the grafts. EC dysfunction and morphological changes were prevented by immunosuppression of recipient rats with cyclosporine. Our study shows that Tx-induced EC dysfunction in rat aortic allografts can be observed within 1 week of Tx in rat aortic allografts and that this is occurring concomitantly with enhanced leukocyte adhesion to the graft ECs. These changes occur before any other morphological or functional changes described thus far in this model and appear to be immune-driven. Taken together, these results show that Tx-induced early EC dysfunction, as described in patients, may be studied in the model of rat aortic Tx.

Immunologic monitoring of the beneficial effect of one HLA-DR-shared blood transfusion in heart transplant patients

Background: Pre-transplant blood transfusion (BT) results in better graft survival in organ transplant recipients, especially when BT donor and allograft recipient share an HLA-DR antigen. Although the immunologic mechanisms involved are still poorly understood, we wanted to know whether down regulation of donor-reactive T cells play a role. Methods In a retrospective study, we analyzed the clinical effects of BT for 45 heart transplant (HTx) patients who had each received 1 BT that shared an HLA-DR-antigen with the recipient, and 55 who had a DR-mismatched BT before heart transplantation. From 30 patients, 15 with DR-shared BT and 15 with DR-mismatched BT, peripheral blood lymphocytes (PBL) were available. From each patient, we analyzed PBL samples taken at the day of transplantation (pre-transplant), and 1 to 2 months, 5 to 7 months, 9 to 14 months, 2 years, and 6 to 7 years after transplantation. Cytotoxic T-lymphocyte precursors (CTLp) and helper T-lymphocyte precursors (HTLp) were measured in a combined limiting dilution assay. Results Analysis of survival during the first 10 years revealed a significantly ( p = 0.016) better survival rate in the group of patients who had received HLA-DR–shared BT compared with the group who had received HLA-DR–mismatched BT. Patients of the DR-shared group experienced significantly ( p = 0.042) less acute rejections compared with the patients who received DR-mismatched BT. We found no differences in the development of graft vascular disease. Frequencies of CTLp specific for the organ donor did not change with time after transplantation in the individual patients, nor did we detect any differences between the two BT groups. We found the same for organ donor–specific HTLp frequencies. Conclusions These data suggest again that transfusion effect depends on HLA-DR compatibility between the heart transplant recipient and the pre-transplant BT donor. The mechanism that caused better survival rate was not down regulation of the donor-reactive T-cell frequency.

Sirolimus (rapamycin) halts and reverses progression of allograft vascular disease in non-human primates.

Current immunosuppressive protocols fail to prevent chronic rejection often manifested as graft vascular disease (GVD) in solid organ transplant recipients. Several new immunosuppressants including sirolimus, a dual function growth factor antagonist, have been discovered, but studies of drug efficacy have been hampered by the lack of a model of GVD in primates, as a prelude to clinical trials. As described earlier, we have developed a novel non-human primate model of GVD where progression of GVD is quantified by intravascular ultrasound (IVUS). Twelve cynomolgus monkeys underwent aortic transplantation from blood group compatible but mixed lymphocyte reaction-mismatched donors. To allow the development of GVD in the allograft, no treatment was administered for the first 6 weeks. Six monkeys were treated orally with sirolimus from day 45 after transplantation to day 105. Progression of GVD measured as change in intimal area from day 42 to 105 was halted in sirolimus-treated monkeys compared to untreated monkeys (P<0.001, general linear model). On day 105, the intimal area +/- SEM was 3.7+/-1.0 and 6.4+/-0.5 mm2, respectively (P<0.05, t test). The magnitude of allograft intimal area on day 105 correlated inversely with sirolimus trough levels (R2=0.67, P<0.05). Regression of the intimal area was seen in four of six sirolimus-treated monkeys, which was significantly different from the untreated monkeys (P<0.05). Our results in the first non-human primate model of GVD showed that treatment with sirolimus not only halted the progression of preexisting GVD but also was associated with partial regression. Sirolimus trough blood levels were correlated with efficacy. Therefore, sirolimus has the potential to control clinical chronic allograft rejection.

Intragraft platelet-derived growth factor-α and transforming growth factor-β1 during the development of accelerated graft vascular disease after clinical heart transplantation

This study was to determine whether the growth factors platelet-derived growth factor-alpha (PDGF-α) and transforming growth factor-betal (TGF-β1) contribute to the development of graft vascular disease (GVD) after clinical heart transplantation. We analysed intragraft PDGF-α and TGF-β1 messenger RNA (mRNA) expression levels by competitive template reverse transcriptase polymerase chain reaction (RT-PCR). Endomyocardial biopsies (EMB) were obtained at 1 and 9 months post-transplant from cardiac allograft recipients with ( n = 11) and without ( n = 11) angiographic evidence of GVD at 1 year. In 1-month EMB, comparable TGF-β1 mRNA levels were found in patients with and without GVD at 1 year ( p = 0.84, Mann-Whitney U-test). In contrast, in 9-month EMB during the development of GVD, intragraft mRNA levels of both PDGF-α ( p = 0.08) and TGF-β1 ( p = 0.03) were higher in patients with GVD after the first year compared to patients without GVD. These results suggest that intragraft PDGF-α and TGF-β1 play a role in the pathogenesis of accelerated GVD after clinical heart transplantation.

Upregulated transforming growth factor-β 1 mRNA expression in endomyocardial biopsies during the development of graft vascular disease after clinical heart transplantation

Upregulated transforming growth factor-β 1 mRNA expression in endomyocardial biopsies during the development of graft vascular disease after clinical heart transplantation

Prevention of renal allograft rejection in primates by blocking the B7/CD28 pathway.

There is accumulating evidence that blockade of the costimulatory pathways offers a valid approach for immune suppression after solid organ transplantation. In this study, the efficacy of anti-CD80 and anti-CD86 monoclonal antibodies (mAbs) in combination with cyclosporine (CsA) to prevent renal allograft rejection was tested in non-human primates. Rhesus monkeys were transplanted with a partly major histocompatibility complex-matched kidney on day 0. Anti-CD80 and anti-CD86 mAbs were administered intravenously daily for 14 days starting at day - 1. CsA was given intramuscularly for 35 days starting just after transplantation. The kidney function was monitored by determining serum creatinine levels. The combination of anti-CD80 and anti-CD86 mAbs completely abrogated the mixed lymphocyte reaction. Untreated rhesus monkeys rejected the kidney allograft in 5-7 days. Treatment with anti-CD80 plus anti-CD86 mAbs resulted in a significantly prolonged graft survival of 28+ 7 days (P=0.025). There were no clinical signs of side effects or rejection during treatment. Kidney graft rejection started after the antibody therapy was stopped. The anti-mouse antibody response was delayed from day 10 to 30 after the first injection. No difference in graft survival was observed between animals treated with CsA alone or in combination with anti-CD80 and anti-CD86 mAbs. However, treatment with anti-CD80 and anti-CD86 mAbs reduced development of vascular rejection. In combination, anti-CD80 and antiCD86 mAbs abrogate T-cell proliferation in vitro, delay the anti-mouse antibody response in vivo, and prevent graft rejection and development of graft vascular disease in a preclinical vascularized transplant model in non-human primates.

Donor-specific CTL frequencies in peripheral blood in relation to graft vascular disease after clinical heart transplantation.

Cellular mechanisms may play a role in the development of graft vascular disease (GVD). We previously demonstrated that GVD correlated with an increase of donor-specific T-helper 1 cytokine production by graft-infiltrating lymphocytes but not by peripheral blood mononuclear cells (PBMC). These T-helper 1 cytokines aid the generation of cytotoxic T-lymphocytes (CTL). In the present report, we investigated whether there is a relationship between the frequency of donor-specific CTL precursors (pCTL) in PBMC and the development of GVD. We tested PBMC samples of five patients with GVD and five patients without GVD in the periods 3-6 months, 1 year, and 3 years after heart transplantation. At all time points, GVD was not related to the number of pCTL. In conclusion, donor-specific cellular tests in peripheral blood could not be related to GVD. Apparently, donor-specific reactions associated with the induction of GVD can only be monitored in the graft.

Donor-specific cytokine production by graft-infiltrating lymphocytes induces and maintains graft vascular disease in human cardiac allografts.

The development of graft vascular disease (GVD) in the allograft is a major impediment for long-term survival of heart transplant recipients. GVD may be mediated by cellular processes, in response to the transplanted heart, and regulated by cytokines. We studied donor-specific cytokine production patterns in graft-infiltrating lymphocyte cultures propagated from endomyocardial biopsies. The biopsies were derived from patients with and without signs of GVD, as diagnosed by angiography at 1 year after heart transplantation. In the first year after transplantation, significantly more T-helper (Th) 1 cytokines (interleukin [IL]-2: P=0.04; interferon-gamma: P=0.01), but not Th2 (IL-4 and IL-6) cytokines, were produced by cultures of patients with GVD compared with patients without GVD. Thereafter, the Th1 cytokine levels in patients with GVD normalized to the levels of patients without GVD. Detectable levels of IL-6 were produced significantly more often (P=0.009) by cultures obtained more than 1 year after transplantation from patients with GVD. The results suggest that high levels of Th1 cytokines produced by graft-infiltrating lymphocytes early after transplantation may be responsible for activation of vascular endothelium, leading to the migration and proliferation of smooth muscle cells that is characteristic of GVD. IL-6, produced later after transplantation, continues this process by promoting smooth muscle cell proliferation.

Phenotypic analysis of lymphocytes infiltrating human cardiac allografts during acute rejection and the development of graft vascular disease

Abstract Acute rejection (AR) and graft vascular disease (GDV) are processes mediated, at least in part, by cellular processes. Therefore, we cultured graft-infiltrating lymphocytes (GIL) from endomyocardial biopsies (EMB) taken during the first year after transplantation, determined their phenotypic composition, and correlated it to AR and GVD. We observed more often GIL growth from EMB with AR than from non-rejection EMB (P = 0.02), but no difference was found between patients with and without GVD 1 year after transplantation. CD4 + cells were always more numerous than CD8 + cells, and no difference in phenotypic composition was found between AR and non-rejection EMB nor between EMB derived from patients with or without signs of GVD. In conclusion, AR is correlated with cell growth of EMB, but the development of GVD is not associated with AR, GIL growth from EMB, or their phenotypic composition.

Phenotypic analysis of lymphocytes infiltrating human cardiac allografts during acute rejection and the development of graft vascular disease.

Acute rejection (AR) and graft vascular disease (GDV) are processes mediated, at least in part, by cellular processes. Therefore, we cultured graft-infiltrating lymphocytes (GIL) from endomyocardial biopsies (EMB) taken during the first year after transplantation, determined their phenotypic composition, and correlated it to AR and GVD. We observed more often GIL growth from EMB with AR than from non-rejection EMB (P = 0.02), but no difference was found between patients with and without GVD 1 year after transplantation. CD4+ cells were always more numerous than CD8+ cells, and no difference in phenotypic composition was found between AR and non-rejection EMB nor between EMB derived from patients with or without signs of GVD. In conclusion, AR is correlated with cell growth of EMB, but the development of GVD is not associated with AR, GIL growth from EMB, or their phenotypic composition.