P4688Additional role of unmodifiable risk factors in pulmonary arterial hypertension risk stratification according to current ESC/ERS guidelines

Background

Current pulmonary hypertension (PH) guidelines stratify the risk of patients with pulmonary arterial hypertension (PAH) using a multiparametric approach. Anyway, the role of unmodifiable risk factors is not taken into account.

Purpose

The aim of this study was to evaluate the role of unmodifiable risk factors (age, gender, PAH aetiology) in PAH risk stratification using the recently proposed simplified risk table and to test if these factors influence the response to PAH-specific treatment.

Methods

All patients with PAH referred to a single centre were included from 2003 to 2017. We applied a simplified risk assessment strategy using the following criteria: WHO functional class, 6-min walking distance, right atrial pressure or brain natriuretic peptide plasma levels and cardiac index (CI) or mixed venous oxygen saturation (SvO2). The last 2 criteria were based on which parameter was available; if both were available the worst was chosen. Risk strata were defined as: Low risk= at least 3 low risk and no high-risk criteria; High risk= at least 2 high risk criteria including CI or SvO2; Intermediate risk= definitions of low or high risk not fulfilled. Then we performed multivariate Cox analysis to evaluate what are the independent predictors of survival (age, gender, PAH aetiology together with the recently proposed simplified PAH risk table) and we tested if these factors influence the response to PAH specific therapy comparing the % improvement of hemodynamic parameters from baseline to 3–4 months after starting treatment. Wilcoxon-Mann-Whitney test was used for comparisons.

Results

Six hundreds and twenty-one treatment-naïve patients were enrolled. Age [HR (95% CI) = 1.022 (1.014–1.030); p-value <0.001], male gender [HR (95% CI) = 1.881 (1.479–2.392); p-value <0.001] and connective tissue disease (CTD)-PAH aetiology [HR (95% CI)= 2.278 (1.733–2.995); p-value <0.001] were all independent predictors of prognosis in patients with PAH together with the recently validated simplified PAH risk table [HR (95% CI) = 2.161 (1.783–2.618); p-value <0.001] but they didn't significantly influence the response to PAH specific treatment as shown in the Figure.

Figure 1

Conclusions

Age, gender and CTD-PAH aetiology significantly influence prognosis together with the recently validated simplified PAH risk table but don't significantly influence the response to PAH-specific treatment.

Acknowledgement/Funding

None

P4676Experience of three years of balloon pulmonary angioplasty in a single centre: safety and short term results

Background

Balloon pulmonary angioplasty (BPA) has recently been developed as an alternative and less-invasive treatment strategy for chronic thromboembolic pulmonary hypertension (CTEPH) but therapeutic efficacy and technical safety of the technique have to be established.

Purpose

To examine the effects of BPA on patients with inoperable disease or residual pulmonary hypertension (PH) after pulmonary endarterectomy (PEA).

Methods

From June 2015 to January 2019 we enrolled symptomatic (WHO-FC ≥II) inoperable CTEPH patients and patients with residual PH after PEA. At baseline and after 3 months after last BPA session all patients underwent clinical evaluation, six-minute walking distance (6MWD) and right heart catheterization. For comparisons Friedman test (with Bonferroni post-hoc pairwise analysis) was used.

Results

Forty-one patients [male 49%, median age 65 (52–75) years, 34 inoperable and 7 with residual PH after PEA] were treated for a total of 111 sessions (median number of sessions for each patient: 2); during each session we treated 2 (2.0–2.5) vessels. Results are shown in the Table. Forty patients were treated with medical therapy before BPA (16 with combination therapy). Four pulmonary artery dissection and 2 haemoptysis with clinical impairment were documented during the procedures; 27 patients had lung injury (radiographic opacity with/without hemoptysis and/or hypoxemia), none had renal dysfunction, 6 patients had access site complications. Five patients died during follow-up (none within 30 days from the procedure) because of sepsis (1), heart failure (1), cancer (1), arrhythmic storm (1) and sudden death in a patients with severe coronary atherosclerosis (1).

Table 1 Median (interquartile range) Baseline Baseline ÷ Pre-BPA Pre-BPA Pre-BPA ÷ Post-BPA Post-BPA Global (n=41) 8 (3–49) months (n=41) 10 (6–18) months (n=32) p-value WHO-FC III-IV (%) 88 N.S. 83 <0.05 42 <0.001 6MWD (m) 430 (346–560) N.S. 425 (357–500) <0.05 450 (375–605) <0.001 RAP (mmHg) 6 (5–8) N.S. 6 (5–8) N.S. 6 (4–8) 0.023 mPAP (mmHg) 46 (40–52) <0.05 43 (33–50) <0.05 36 (28–41) <0.001 CI (l/min/m2) 2.6 (2.2–3.0) N.S. 2.7 (2.2–3.0) <0.05 3.1 (2.6–3.5) 0.004 PVR (WU) 7.5 (5.6–11.5) <0.05 6.5 (4.7–10.3) <0.05 4.1 (3.3–5.9) <0.001 PA O2 Sat (%) 69 (63–71) N.S. 69 (63–72) N.S. 69 (63–73) 0.002 CI, Cardiac Index; mPAP, mean Pulmonary Arterial Pressure; PVR, Pulmonary Vascular Resistance; PA O2 Sat, Pulmonary Artery Oxygen Saturation; RAP, Right Atrial Pressure; 6MWD, 6 Minute Walking Distance; WHO-FC, World Health Organization Functional Class.

Conclusions

BPA is a safe and effective treatment able to improve symptoms and hemodynamic profile in inoperable CTEPH patients and in patients with residual PH after PEA.

Acknowledgement/Funding

None

P4680Prognostic value of stroke volume index in patients with pulmonary arterial hypertension at intermediate risk

Background

Current pulmonary hypertension (PH) guidelines stratify the risk of patients with pulmonary arterial hypertension (PAH) using a multiparametric approach. Low, intermediate and high-risk are defined by estimated 1-year mortality of <5%, 5–10% and >10%, respectively. This risk assessment has been recently validated in 3 cohorts of PAH patients and a simplified risk table for patients with idiopathic/heritable (I/H) PAH and PAH associated with connective tissue disease (CTD) and congenital heart disease (CHD) has been recently proposed and validated. However, with this method most of the patients are classified in the intermediate risk category and additional strategies are required to further stratify this group of PAH patients.

Purpose

To evaluate the prognostic value of SVI measured with right heart catheterization (RHC) in patients at intermediate-risk.

Methods

All treatment naïve patients with I/H-PAH, CTD-PAH and CHD-PAH referred to a single centre were included from 2003 to 2017. All patients were assessed at baseline and at the 1st follow-up at 3–4 months after starting PAH-specific therapy (1st F-UP) with RHC, brain natriuretic peptide (BNP) plasma levels, 6-min walking distance (6MWD) and WHO functional class. We applied a simplified risk assessment strategy using the following criteria: WHO functional class, 6MWD, right atrial pressure or BNP plasma levels and cardiac index (CI) or mixed venous oxygen saturation (SvO2). The last 2 criteria were based on which parameter was available; if both were available the worst was chosen. Risk strata were defined as: Low risk= at least 3 low risk and no high-risk criteria; High risk= at least 2 high risk criteria including CI or SvO2; Intermediate risk= definitions of low or high risk not fulfilled. The prognostic value of SVI was assessed using Cox regression analysis. Intermediate risk patients were further stratified in intermediate-low and intermediate-high risk taking into account the value of SVI that best discriminate prognosis (according to ROC curve analysis). Kaplan Meier curves and Log-rank test were used for survival analysis.

Results

Seven hundreds and twenty-five patients were enrolled. SVI is able to stratify the prognosis of PAH patients at 1st F-UP [HR 0.979 (0.964–0.994), p-value= 0.008] but not at baseline [HR 0.986 (0.970–1.002), p-value= 0.085]. The best predictive cut-off value is 38 ml/m2 (AUC= 0.66, sensitivity= 73%, specificity= 59%). Survival curves are shown in the Figure.

Figure 1

Conclusions

SVI assessed at 1st F-UP is predictive of prognosis and the cut off value of 38 ml/m2 is able to further stratify the survival of intermediate risk PAH patients.

Acknowledgement/Funding

None

Cord blood-derived cytokine-induced killer cells combined with blinatumomab as a therapeutic strategy for CD19+ tumors

BACKGROUND

Cytokine-induced killer cells (CIKs) are an advanced therapeutic medicinal product (ATMP) that has shown therapeutic activity in clinical trials but needs optimization. We developed a novel strategy using CIKs from banked cryopreserved cord blood units (CBUs) combined with bispecific antibody (BsAb) blinatumomab to treat CD19⁺ malignancies.

METHODS

CB-CIKs were expanded in vitro and fully characterized in comparison with peripheral blood (PB)-derived CIKs.

RESULTS

CB-CIKs, like PB-CIKs, were mostly CD3⁺ T cells with mean 45% CD3⁺CD56⁺ and expressing mostly TCR(T cell receptor)αβ with a TH1 phenotype. CB-CIK cultures had, however, a larger proportion of CD4⁺ cells, mostly CD56^-, as well as a greater proportion of naïve CCR7⁺CD45RA⁺ and a lower percentage of effector memory cells, compared with PB-CIKs. CB-CIKs were very similar to PB-CIKs in their expression of a large panel of co-stimulatory and inhibitory/exhaustion markers, except for higher CD28 expression among CD8⁺ cells. Like PB-CIKs, CB-CIKs were highly cytotoxic in vitro against natural killer (NK) cell targets and efficiently lysed CD19⁺ tumor cells in the presence of blinatumomab, with 30-60% lysis of target cells at very low effector:target ratios. Finally, both CB-CIKs and PB-CIKs, combined with blinatumomab, showed significant therapeutic activity in an aggressive PDX Ph⁺ CD19⁺ acute lymphoblastic leukemia model in NOD-SCID mice, without sign of toxicity or graft-versus-host disease. The improved expansion protocol was finally validated in good manufacturing practice conditions, showing reproducible expansion of CIKs from cryopreserved cord blood units with a median of 28.8 × 10⁶ CIK/kg.

DISCUSSION

We conclude that CB-CIKs, combined with bispecific T-cell-engaging antibodies, offer a novel, effective treatment strategy for leukemia.

Phase II Study of Sequential Infusion of Donor Lymphocyte Infusion and Cytokine-Induced Killer Cells for Patients Relapsed after Allogeneic Hematopoietic Stem Cell Transplantation

Seventy-four patients who relapsed after allogeneic stem cell transplantation were enrolled in a phase IIA study and treated with the sequential infusion of donor lymphocyte infusion (DLI) followed by cytokine-induced killer (CIK) cells. Seventy-three patients were available for the intention to treat analysis. At least 1 infusion of CIK cells was given to 59 patients, whereas 43 patients received the complete cell therapy planned (58%). Overall, 12 patients (16%) developed acute graft-versus-host disease (aGVHD) of grades I to II in 7 cases and grades III to IV in 5). In 8 of 12 cases, aGVHD developed during DLI treatment, leading to interruption of the cellular program in 3 patients, whereas in the remaining 5 cases aGVHD was controlled by steroids treatment, thus allowing the subsequent planned administration of CIK cells. Chronic GVHD (cGVHD) was observed in 11 patients (15%). A complete response was observed in 19 (26%), partial response in 3 (4%), stable disease in 8 (11%), early death in 2 (3%), and disease progression in 41 (56%). At 1 and 3 years, rates of progression-free survival were 31% and 29%, whereas rates of overall survival were 51% and 40%, respectively. By multivariate analysis, the type of relapse, the presence of cGVHD, and a short (<6 months) time from allogeneic hematopoietic stem cell transplantation to relapse were the significant predictors of survival. In conclusion, a low incidence of GVHD is observed after the sequential administration of DLI and CIK cells, and disease control can be achieved mostly after a cytogenetic or molecular relapse.

Kinetics of the use of cryopreserved autologous stem cell grafts: a GITMO-SIDEM survey

BACKGROUND AIMS

Hematopoietic stem cell cryopreservation significantly contributed to autologous stem cell transplantation (ASCT). Cryopreserved stem cell units (SCU) are expected to be used soon after harvesting for most purposes, but, in a number of cases, they remain stored for some time, creating an increasing load for SCU depositories. Disposal policies vary widely in each center, and the existing guidelines are insufficient.

METHODS

We conducted a survey of seven Gruppo Italiano Trapianto di Midollo Osseo centers to investigate the outcome of SCU harvested from January 2005 to December 2009 for ASCT. The data from 1603 collections were gathered, for a total of 5822 SCU.

RESULTS

In our cohort, 79% of patients collected >5 × 10⁶ CD34+ cells/kg, and 3.4% collected <2 × 10⁶ CD34+ cells/kg. Up to 21% of all the patients and 42% of those with acute leukemia did not undergo reinfusion, and 37% of the cryopreserved SCU were excess, resulting from patients not reinfusing or partially reinfusing. Less than one-third of the excess SCU was disposed, and the major causes of disposal were death and, in a minority of cases, withdrawal of the indication for ASCT. In our analysis, very few first reinfusions occurred after 2 years, and those after 5 years were exceptional. Through the use of a multivariate analysis, we sought to identify the risk factors for collection non-use, independent of the centers' policies. Non-use of SCU was significantly associated with patients with acute leukemia, collections of <2 × 10⁶ CD34/kg and lower age groups.

CONCLUSIONS

These data serve as a valid basis to support rational recommendations for cost-effective storage and disposal of SCU.

Incidence of primary and second cancers in renal transplant recipients: a multicenter cohort study

Limited data exist about cancer prognosis and the development of second cancers in renal transplant recipients. In a retrospective cohort study on 3537 patients incidence rates of the first and, if any, of a second cancer, and standardized incidence ratios [SIR (95% CI)] were computed. Two hundred and sixty-three (7.5%) patients developed a NMSC, and 253 (7.2%) another type of cancer after a median follow-up of 6.5 and 9.0 years, respectively. A statistically significant excess risk, if compared to an age- and sex-matched reference general population, was observed for Kaposi sarcoma and NMSC, followed by non-Hodgkin lymphoma and carcinoma of cervix uteri; a small number of unusual cancers such as tumors of the salivary glands, small intestine and thyroid also were detected at a level worthy of additional scrutiny. Ten-year survival rate of all noncutaneous cancers was 71.3%, with lower rates for lung carcinoma and non-Hodgkin lymphoma (0% and 41.7%, respectively). Patients with NMSC had an increased risk of developing a second NMSC [SIR 8.3 (7.0-10.0)], and patients with a primary noncutaneous cancer had increased risk of developing a second noncutaneous cancer [SIR 1.8 (1.2-2.8)], if compared to the whole cohort. Our study underscore that the high risk of primary and second cancer in renal transplant recipients, including unusual cancers.

Transfer of growth factor receptor mRNA via exosomes unravels the regenerative effect of mesenchymal stem cells

Bone marrow-mesenchymal stem cells (BM-MSC) ameliorate renal dysfunction and repair tubular damage of acute kidney injury by locally releasing growth factors, including the insulin-like growth factor-1 (IGF-1). The restricted homing of BM-MSC at the site of injury led us to investigate a possible gene-based communication mechanism between BM-MSC and tubular cells. Human BM-MSC (hBM-MSC) released microparticles and exosomes (Exo) enriched in mRNAs. A selected pattern of transcripts was detected in Exo versus parental cells. Exo expressed the IGF-1 receptor (IGF-1R), but not IGF-1 mRNA, while hBM-MSC contained both mRNAs. R- cells lacking IGF-1R exposed to hBM-MSC-derived Exo acquired the human IGF-1R transcript that was translated in the corresponding protein. Transfer of IGF-1R mRNA from Exo to cisplatin-damaged proximal tubular cells (proximal tubular epithelial cell [PTEC]) increased PTEC proliferation. Coincubation of damaged PTEC with Exo and soluble IGF-1 further enhanced cell proliferation. These findings suggest that horizontal transfer of the mRNA for IGF-1R to tubular cells through Exo potentiates tubular cell sensitivity to locally produced IGF-1 providing a new mechanism underlying the powerful renoprotection of few BM-MSC observed in vivo.

Ofatumumab is more efficient than rituximab in lysing B chronic lymphocytic leukemia cells in whole blood and in combination with chemotherapy

Ofatumumab (OFA) is a human anti-CD20 Ab approved for treatment of fludarabine-refractory B chronic lymphocytic leukemia (B-CLL). The efficacy of different immunotherapeutic strategies is best investigated in conditions that are as physiologic as possible. We have therefore compared the activity OFA and rituximab (RTX), alone or in combination with chemotherapeutic agents in unmanipulated whole blood assays, using flow cytometry. OFA (10-100 μg/ml) lysed B-CLL targets in whole blood more efficiently and with faster kinetics than RTX, with a mean 56% lysis at 24 h compared with 16%. This activity of OFA was fully complement dependent, as shown by >99% inhibition by anti-C5 Ab eculizumab and a lack of NK cell activation in whole blood. OFA-mediated NK cell activation was blocked by complement. OFA-mediated lysis could be increased an additional 15% by blocking CD55 and CD59 complement inhibitors. Interestingly, OFA-mediated lysis correlated significantly with CD20 expression levels (r(2) = 0.79). OFA showed overlapping dose response curves similar to those for RTX in phagocytosis assays using either human macrophages or neutrophils. However, phagocytosis was inhibited in the presence of serum or whole blood. Finally, combined treatment with mafosfamide and fludarabine showed that these therapeutic drugs are synergistic in B-CLL whole blood assays and show superior activity when combined with OFA compared with RTX. These results confirm in B-CLL samples and in physiologic conditions the superior complement mediated cytotoxicity induced by OFA alone compared with RTX, the lack of NK cell activation, and phagocytosis in these conditions and suggest effective chemoimmunotherapy strategies using this new generation anti-CD20 Ab.

Minimally manipulated whole human umbilical cord is a rich source of clinical-grade human mesenchymal stromal cells expanded in human platelet lysate

BACKGROUND AIMS

Mesenchymal stromal cells (MSC) have recently been identified as a therapeutic option in several clinical conditions. Whereas bone marrow (BM) is considered the main source of MSC (BM-MSC), the invasive technique required for collection and the decline in allogeneic donations call for alternative sources. Human umbilical cord (UC) represents an easily available source of MSC (UC-MSC).

METHODS

Sections of full-term UC were transferred to cell culture flasks and cultured in 5% human platelet lysate (PL)-enriched medium. Neither enzymatic digestion nor blood vessel removal was performed. After 2 weeks, the adherent cells were harvested (P1), replated at low density and expanded for two consecutive rounds (P2 and P3).

RESULTS

We isolated and expanded MSC from 9/9 UC. UC-MSC expanded with a mean fold increase (FI) of 42 735 ± 16 195 from P1 to P3 in a mean of 29 ± 2 days. By processing the entire cord unit, we theoretically could have reached a median of 9.5 × 10(10) cells (ranging from 1.0 × 10(10) to 29.0 × 10(10)). UC-MSC expressed standard surface markers; they contained more colony-forming unit (CFU)-fibroblast (F) and seemed less committed towards osteogenic, chondrogenic and adipogenic lineages than BM-MSC. They showed immunosuppressive properties both in vitro and in an in vivo chronic Graft versus Host disease (cGvHD) mouse model. Both array-Comparative Genomic Hybridization (CGH) analysis and karyotyping revealed no chromosome alterations at the end of the expansion. Animal studies revealed no tumorigenicity in vivo.

CONCLUSIONS

UC constitute a convenient and very rich source of MSC for the production of third-party 'clinical doses' of cells under good manufacturing practice (GMP) conditions.

Mechanism of action of type II, glycoengineered, anti-CD20 monoclonal antibody GA101 in B-chronic lymphocytic leukemia whole blood assays in comparison with rituximab and alemtuzumab

We analyzed in B-chronic lymphocytic leukemia (B-CLL) whole blood assays the activity of therapeutic mAbs alemtuzumab, rituximab, and type II glycoengineered anti-CD20 mAb GA101. Whole blood samples were treated with Abs, and death of CD19(+) B-CLL was measured by flow cytometry. Alemtuzumab efficiently lysed B-CLL targets with maximal lysis at 1-4 h (62%). In contrast, rituximab induced a more limited cell death (21%) that was maximal only at 24 h. GA101 killed B-CLL targets to a similar extent but more rapidly than rituximab, with 19.2 and 23.5% cell death at 4 and 24 h, respectively, compared with 7.9 and 21.4% for rituximab. Lysis by both rituximab and GA101 correlated directly with CD20 expression levels (r(2) = 0.88 and 0.85, respectively). Interestingly, lysis by all three Abs at high concentrations was mostly complement dependent, because it was blocked by the anti-C5 Ab eculizumab by 90% in the case of alemtuzumab and rituximab and by 64% in the case of GA101. Although GA101 caused homotypic adhesion, it induced only limited (3%) direct cell death of purified B-CLL cells. Both rituximab and GA101 showed the same efficiency in phagocytosis assays, but phagocytosis was not significant in whole blood due to excess Igs. Finally, GA101 at 1-100 μg/ml induced 2- to 3-fold more efficient NK cell degranulation than rituximab in isolated B-CLL or normal PBMCs. GA101, but not rituximab, also mediated significant NK cell degranulation in whole blood samples. Thus, complement and Ab-dependent cellular cytotoxicity are believed to be the major effector mechanisms of GA101 in whole blood assays.

Pheohyphomycotic soft tissue disease caused by Alternaria alternata in a kidney transplant patient: a case report and literature review

A 61-year-old Italian man, who underwent a renal transplantation 8 years ago, receiving azathioprine, prednisone, and cyclosporine for immunosuppressive therapy, presented with a large reddish indurated plaque with a central ulcer, which was slowly enlarged, on the right knee. From the diseased tissue biopsy, a dematiaceous fungus matching Alternaria alternata in all essential characters was isolated in pure culture. This is an uncommon fungal complication in a kidney transplant patient. A detailed morphological description of the isolate is provided as well as review of the literature.

Phaeoacremonium parasiticum subcutaneous infection in a kidney-transplanted patient successfully treated by surgery

Human infection caused by Phaeoacremonium parasiticum is increasingly being reported. However, only a few case reports show its role as a soil-related contaminant of kidney recipients. We report here a case of a subcutaneous infection by P. parasiticum in a transplanted man. After 4 years, he reported a nonpainful nodule on his forefinger. It was surgically excised. Histological examination revealed dense fibrous connective tissue showing an extensive granulomatous reaction, including the presence of a wooden sliver, and hyaline, branched, and septate hyphae. Six months later, the patient relapsed and underwent large excision. Culture was positive for P. parasiticum. No antifungal drug was administered. Surgical excision was successful.

Scedosporium apiospermum Soft-Tissue Infection: A Case Report and Review of Kidney Transplant Literature

Scedosporium apiospermum is an environmental mould. Human infections caused by this organism have been observed; however, only a few case reports show its role as a telluric contaminant to kidney recipients. We have reported here a case of a dramatic soft tissue infection by S. apiospermum in a kidney-transplanted man. Surgical drainage together with voriconazole systemic therapy was successful.

Influence of co-medication with sirolimus or cyclosporine on mycophenolic acid pharmacokinetics in kidney transplantation

The pharmacokinetics of mycophenolic acid (MPA)--the active metabolite of mycophenolate mofetil (MMF)--is significantly influenced by co-medications. The impact of sirolimus on daily MPA exposure, however, has not been investigated so far. As a part of the study aimed at investigating the efficacy of Campath-1H induction therapy in a steroid-free regimen in kidney transplantation, MPA plasma levels were serially measured in 21 patients treated with low-dose sirolimus (SRL) or low-dose CsA both in addition to low-dose MMF over 12 months post-operatively. Full pharmacokinetic profiles were compared at month 6 and 12 post-surgery. Mean dose-adjusted MPA trough levels were 4.4-fold higher in patients on combined SRL and MMF than in those given CsA and MMF. Pharmacokinetic studies demonstrated that mean MPA C(max) and T(max) were comparable in the two groups, while mean MPA AUC(0-12) was higher in SRL than CsA treated patients. The pharmacokinetic profile of SRL- but not of CsA-group showed a second peak consistent with the enterohepatic recirculation of MPA. These findings suggest that SRL and CsA have different effects on MPA metabolism and/or excretion eventually affecting its immunosuppressive property and/or toxicity. CsA, but not SRL, inhibits MPA enterohepatic recirculation, reducing MPA daily exposure.

Blood Cyclosporine Level Soon After Kidney Transplantation is a Major Determinant of Rejection: Insights From the Mycophenolate Steroid-Sparing Trial

Target organs express antigens directly recognized by antigen-specific T cells, thereby precipitating rejection. When early T-cell activation is inhibited, there is a low risk of rejection. We sought to determine the predictive values of serial posttransplant blood cyclosporine trough (C(0)) concentrations to minimize the risk for a first rejection episode compared with 2-hour postdose (C(2)) drug concentrations. The final aim of the study was to identify a concentration range for the best predictive pharmacokinetic parameter that should be targeted to reduce the risk of rejection. This possibility was explored in 334 de novo kidney transplant recipients who participated in the prospective, multicenter Mycophenolate Steroid-Sparing Trial. Among measurements performed during the first 6 months postsurgery, cyclosporine C(0) levels measured early after transplantation were the strongest predictor of acute graft rejection. Levels within 300 to 440 ng/mL were associated with the lowest risk of rejection, while patients with levels lower than 300 ng/mL showed a more than double risk. Cyclosporine trough values predicted allograft rejection with an accuracy of 74%, while C(2) levels had no predictive value. These findings underline the need to target cyclosporine therapy early posttransplant to modulate T-cell activation.

[Renal transplantation in the North Italy Transplant program (NITp): Organ allocation and results]

Renal transplantation is an effective therapeutic tool for patients with end-stage renal diseases (ESRDs). Data reported in this article summarize the results obtained from 30 years' activity in the North Italy Transplant program (NITp), the first transplant organization in Italy that implemented a donor procurement and organ transplantation network. In the NITp kidney allocation is governed by a computerized algorithm, NITK3, put in place in 1997, aimed at ensuring equity, transparency and traceability during the stages of the allocation decision-making process. The NITp working group has recognized the NITK3 criteria and they are periodically reviewed following the results of the analysis of patients' transplantation odds. The results obtained with the use of the NITK3 algorithm have been very satisfactory: after 6 yrs, a significantly higher percentage of patients at immunological risk (sensitized or waiting for re-transplant), of patients waiting for >3 yrs and of patients with 0-1 HLA A,B,DR mismatches have been transplanted. Moreover, a higher percentage of kidneys were used locally (in a hospital within the procurement area), and this is known to stimulate donor procurement. Finally, we performed a preliminary statistical analysis of transplants carried out from 1998-2002 in 5/16 centers of the NITp area, demonstrating the quality of the NITp program in terms of patient and graft survival, and that donor and recipient age are the variables significantly impacting on transplant results.

Pharmacokinetics help optimizing mycophenolate mofetil dosing in kidney transplant patients

BACKGROUND

Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), is now routinely used as immunosuppressant in solid organ transplantation in a fixed daily dose regimen (2 g/d) in association with cyclosporine (CsA) and steroids. However, no correlation has been shown between fixed MMF dose and clinical outcome.

METHODS

Here we examined the possibility of optimizing MMF dosing by drug pharmacokinetic monitoring in 46 stable kidney transplant recipients. MPA plasma concentration profiles were measured by a reverse-phase high-performance liquid chromatography method 6-9 months after transplantation and related with routine laboratory analysis tests. Since MPA is extensively bound to serum albumin and only the free fraction is pharmacologically active, in a subgroup of 23 patients free plasma MPA was also determined.

RESULTS

Despite a comparable MMF dose, a large interindividual variability in both MPA area under the curve (AUC) from 0 to 12 h (range 10.1-99.8 microg/mL. h) and in trough levels (range 0.24-7.04 microg/mL) was found. Patients with AUC >40 microg/mL. h showed a better (p<0.05) renal function than patients with lower AUC (creatinine clearance 85.7+/-23.2 versus 64.5+/-17.5 mL/min), despite no difference in CsA dose, CsA AUC and blood CsA trough level. The percentage of free plasma MPA but not total MPA correlated with the red blood cell and leukocyte count.

CONCLUSIONS

Therapeutic MMF drug monitoring might contribute to a better management of kidney transplant recipient with the goal of optimizing drug dosing and limiting the risk of MMF-related toxicity.

The kidney transplant program at the Bergamo Center

The kidney transplant program at the Ospedali Riuniti of Bergamo, Italy was established in 1989. Since its inception, 367 patients have been transplanted, including 357 kidney transplants from cadaveric donors and 10 from living-related donors. Overall 8-year patient and graft survival rates were 94% and 77%, respectively. By 1995 our unit co-ordinated the activity of the Department of Immunology and Clinics of Organ Transplantation, Ospedali Riuniti--Mario Negri Institute for Pharmacological Research, Bergamo. The dual "marginal" kidney transplant program in the same recipient was launched in August 1997, as a part of an international cooperative network which established the "Double Kidney Transplant Group" (DKG). To date, 19 dual kidney transplants have been successfully performed in our center. Four combined heart-kidney transplants and 2 combined liver-kidney transplants have also been performed. During the past 4 years several studies involving conventional antirejection drugs were carried out, particularly focussing our attention on cyclosporine (CsA) through pharmacokinetic and pharmacodynamic approaches: 1) a simplified method to evaluate daily exposure to CsA has been set up; 2) the monitoring of calcineurin activity in whole blood samples was evaluated as a way to optimize CsA dosing. As for the new immunosuppressants, studies are ongoing with mycophenolate mofetil (MMF). We are co-ordinating a prospective multicenter randomized trial of steroid sparing in kidney transplant recipients given MMF or azathioprine as a part of their immunosuppression therapy (MY.S.S. study). This involves 9 Italian transplant centers and 2 European centers. Up to now 325 patients have been randomized. Moreover we have set up an HPLC method for measuring plasma mycophenolic acid (MPA), and examined the possibility of optimizing MMF dosing by drug pharmacokinetic monitoring. Further studies have been addressed to chronic allograft nephropathy. The nature and mediators of renal lesions in kidney transplant patients given CsA have been explored taking into account the gene expression of endothelin-1, RANTES and MCP-1 in graft specimens from patients who had evidence of CsA nephrotoxicity, chronic rejection, or no lesions at histological examination. The impact of percutaneous transluminal angioplasty and stenting of posttransplant renal artery stenosis on renal function recovery was also recently examined. From this study we conclude that the procedure is safe and effective to normalize the functional changes sustained by hemodynamically significant artery stenosis. Moreover, Doppler ultrasound scanning is an useful, reliable, non-invasive tool to monitor the renal function response to artery revascularization. Thanks to the long-lasting co-operation with the Negri Bergamo Laboratories, we had in the past and still have an active program in experimental animals to investigate strategies for transplant tolerance and transplant gene therapy, besides addressing some issues related to the immunological barrier of xenotransplantation.

Risk of nonmelanoma skin cancer in Italian organ transplant recipients. A registry-based study

BACKGROUND

Organ transplant recipients are at an increased risk of nonmelanoma skin cancer. Few data concern heart transplantation and populations from southern Europe.

METHODS

A total of 1,329 patients who received their first kidney (1,062 subjects) or heart allograft (267 subjects) were included in a partly retrospective cohort study to evaluate the risk of skin cancer. The incidence rate per 1,000 person-years and the cumulative incidence were computed. Standardized morbidity ratio was estimated by comparison with Italian cancer registry data. To analyze the role of potential prognostic factors, Cox's regression method was used.

RESULTS

The overall incidence rate of nonmelanoma skin cancer was 10.0 cases per 1,000 posttransplant person-years (95% confidence interval 8.2-11.7). This estimate was far higher than expected in the general population. The overall risk of developing skin cancer increased from a cumulative incidence of 5.8% after 5 posttransplant years to an incidence of 10.8% after 10 years of graft survival. In a Cox proportional hazard risk model, the most important factors that appeared to favor the development of skin cancer were age at transplantation and sex. After adjustment for age at transplantation and sex, no definite increased risk was documented among heart as compared with kindney transplant recipients.

CONCLUSIONS

Our study confirms the increased risk of nonmelanoma skin cancer among organ transplant recipients in a southern European population.

Recurrence after first cerebral infarction in young adults

OBJECTIVE

We have investigated recurrence of stroke in a consecutive series of young adults, aged 16 to 45 years, after a first cerebral infarction.

METHODS

From January 1, 1988 to December 31, 1996 we submitted those patients to a diagnostic protocol including angiographic, cardiological, and haematological investigations. The patients were followed at 6 month intervals up to December 31, 1998.

RESULTS

We have evaluated and followed-up 135 patients, 71 men and 64 women, who were 3.99% of all the admitted stroke patients. At 12 months after stroke, 83 patients had returned to work, 40 patients were mildly to moderately handicapped, 4 were using a wheel-chair, and 8 had died. Follow-up was 26 to 123 months (mean 68.8). Recurrence of stroke, always of ischaemic nature, was seen in 15 patients (11.1%), 3 to 76 months after the first stroke (mean 27.4), for an annual incidence of 2.26%. Recurrence was significantly associated with Partial Anterior Circulation Syndrome and Haematological subtype of first stroke (respectively, P = 0.0209 and P = 0.0135, chi2 test), but not with age (< or = or > 35 years) or risk factors. Repetition of stroke was never fatal, but it caused heavy disability in 13 patients, 8 of whom had completely or nearly completely recovered after the first event.

CONCLUSIONS

Our data suggest that recurrence of stroke is a major clinical problem also for the patients aged less than 45 years and that it might be more frequent with specific clinical syndromes and etiologic subtypes of first stroke.

Epstein-Barr virus-negative lymphoproliferate disorders in long-term survivors after heart, kidney, and liver transplant

BACKGROUND

Solid organ transplant patients undergoing long-term immunosuppression have high risk of developing lymphomas. The pathogenesis of the late-occurring posttransplantation lymphoproliferative disorders (PTLD) have not yet been extensively investigated.

METHODS

We studied 15 patients who developed PTLD after a median of 79 months (range 22-156 months) after organ transplant. Clonality, presence of Epstein-Barr virus (EBV) genome, and genetic lesions were evaluated by Southern blot analysis or polymerase chain reaction.

RESULTS

All monomorphic PTLD and two of three polymorphic PTLD showed a monoclonal pattern. Overall, 44% of samples demonstrated the presence of the EBV genome. Within monomorphic PTLD, the EBV-positive lymphomas were even lower (31%). A c-myc gene rearrangement was found in two cases (13%), whereas none of the 15 samples so far investigated showed bcl-1, bcl-2, or bcl-6 rearrangement. The modulation of immunosuppression was ineffective in all patients with monomorphic PTLD independent of the presence of the EBV genome. The clinical outcome after chemotherapy was poor because of infectious complications and resistant disease. With a median follow-up of 4 months, the median survival time of these patients was 7 months.

CONCLUSIONS

Late occurring lymphomas could be considered an entity distinct from PTLD, occurring within 1 year of transplant, because they show a histological and clinical presentation similar to lymphomas of immunocompetent subjects, are frequently negative for the EBV genome, are invariably clonal, and may rearrange the c-myc oncogene. New therapeutic strategies are required to reduce the mortality rate, and new modalities of long-lasting immunosuppression are called for.

Nature and mediators of renal lesions in kidney transplant patients given cyclosporine for more than one year

BACKGROUND

Cyclosporine (CSA) has improved patients and organ-graft survival rates, but its chronic nephrotoxicity is still an issue. Although prolonged vasoconstriction could contribute to chronic CsA tubulointerstitial changes by producing chronic ischemia, this relationship has been difficult to demonstrate thus far, and cellular origin and mediators of these structural alterations remain ill-defined.

METHODS

As a part of a clinical trial in kidney transplant recipients on triple immunosuppressive therapy (CsA, azathioprine and steroid), which includes renal biopsy as "per protocol," 22 patients enrolled between 12 and 24 months posttransplantation underwent renal hemodynamic evaluation by measuring glomerular filtration rate and renal plasma flow by the plasma clearance of unlabeled iohexol and the renal clearance of para-aminohippuric acid, respectively. In parallel, the CsA pharmacokinetic profile was also determined. A week later, a protocol biopsy of kidney graft was performed. Light microscopy examination and localization of endothelin-1, RANTES, monocyte chemoattractant protein-1 gene expression by in situ hybridization in the graft specimens were evaluated and related to the pattern of histologic lesions.

RESULTS

Ten out of 22 kidney transplant recipients who underwent the protocol biopsy had CsA nephrotoxicity, eight had chronic rejection, and four had no lesions at histological examination. The total daily exposure to CsA was higher in patients with CsA nephrotoxicity than in those with chronic rejection or no lesions at biopsy. Renal function was preserved in the CsA toxicity group as compared with the chronic rejection group, despite some degree of renal hypoperfusion. Tubular atrophy and striped interstitial fibrosis were found in all patients with light microscopical evidence of CsA nephrotoxicity, whereas glomerular and arteriolar lesions were less frequent. Intense staining for endothelin-1, RANTES, and monocyte chemoattractant protein-1 mRNAs selectively localized at tubular epithelial cells was found in biopsies taken from patients with CsA nephrotoxicity, but not in the chronic graft rejection group, whose tubuli had only minimal staining for RANTES mRNA on a few occasions.

CONCLUSION

Long-term CsA administration to kidney allograft recipients leads to tubulointerstitial injury independently of its vascular effect. The possible contribution to the development of interstitial fibrosis of inflammatory and growth factors released by tubular cells in which CsA accumulates is proposed.

How to convert from traditional cyclosporine to the microemulsion formulation in stable renal transplant patients?

How to convert from traditional cyclosporine (CsA) to the microemulsion formulation in stable renal transplant patients is still a matter of debate. The present study was designed to evaluate the effects of changeover from traditional Sandimmune to Neoral formulation at two dose-ratio conversions on CsA pharmacokinetics, safety and tolerability particularly in terms of renal function. Thirty outpatients regularly followed at our Clinical Research Center were randomized to 1:1 or 1:0.75 dose-ratio conversion and assigned to the two groups according to a comparable renal function and time post-transplant. Patients underwent CsA pharmacokinetic evaluation and renal function measurements (GFR and RPF) before, at day 15, and at month 6 after conversion to Neoral formulation. More consistent CsA concentration-time profiles with Neoral than traditional formulation were obtained at the two time points of evaluation after conversion. At 1:1 dose-ratio conversion an increased absorption rate, reflected by a shorter time to maximum blood CsA concentration (Tmax), and a greater bioavailability, as shown by an increase in the peak CsA concentration (Cmax) and the 12-h exposure to drug defined by the area under the time-concentration curve (AUC0-->12 h) was found 15 d and 6 months after conversion to Neoral formulation. A similar AUC as compared with traditional Sandimmune was observed in those patients randomized to receive a 25% lower dose of Neoral formulation. All of patients defined as 'low' absorbers became 'high' absorbers as early as 15 d after conversion to Neoral formulation at 1:1 or 0.75 dose-ratio regimen. Overall mean GFR was unchanged in both conversion regimens during the 6 months of follow-up. However, there was a tendency to lower GFR even in some patients randomized to 1:0.75 conversion but mostly in those with 1:1 conversion. A limited sampling strategy utilizing three blood samples (0, 1, 3 h post-dosing of Neoral formulation) provided an excellent correlation with actual drug exposure (r = 0.977). Enhanced CsA absorption with the microemulsion formulation results in increased drug exposure that may reduce GFR in some patients who undergo 1:1 dose-ratio conversion. The Neoral formulation that permits a more effective, consistent, and predictable absorption of CsA may represent a great advantage in order to prevent acute and possibly chronic rejections. Efforts have to be made to find optimal therapeutic range and dosing schedule for this new formulation, which may be facilitated by using the limited sampling approach to predict AUC after only three-point sampling.

Abdominal pain and acute nephritis in a man with a recent renal transplant

We describe a patient with renal transplant who developed abdominal pain and acute nephritis in the course of the follow-up. A biopsy of colon lesions revealed CMV inclusions, renal biopsy revealed acute glomerulonephritis with positive CMV-DNA on polymerase chain reaction. The renal disease and bowel symptoms completely resolved after antiviral treatment.

Upregulation of renal and systemic cyclooxygenase-2 in patients with active lupus nephritis

In lupus nephritis (LN), renal thromboxane A2 (TXA2) production is increased, and inhibition of TXA2 activity improves renal function. In patients with LN, renal function depends very much on vasodilatory prostaglandins, and indeed inhibiting the prostaglandin-forming enzyme cyclooxygenase (COX) with aspirin or related compounds was detrimental on renal hemodynamics in these patients. There are no data so far on whether the excessive TXA2 production in LN derives from upregulation of type I or type II isoforms of COX. It was found that TXB2 synthesis and COX-2 gene expression were higher in peripheral blood mononuclear cells from patients with active LN compared to patients in the inactive form of the disease and to healthy subjects. Unlike COX-2, levels of COX-1 mRNA were comparable in lupus patients and control subjects and were not influenced by the disease activity. Immunoperoxidase studies on kidney biopsies showed COX-1 staining in glomerular arterioles and other renal vessels, with no evident difference between lupus biopsies and control specimens taken from either individuals who were free of renal disease or patients with non-lupus nephropathies. In contrast, COX-2 staining was definitely stronger in specimens from patients with active LN than control specimens. In active LN, COX-2-specific staining was localized mainly in the glomeruli, with a weaker signal on tubuli and in the interstitium. Double-staining studies with an antibody against the macrophage marker CD68 and an anti-COX-2 antibody definitely showed that COX-2 and CD68 often colocalized on the same cell, with only occasional glomerular COX-2-stained mesangial areas. Patients with non-lupus nephropathies had no increase in renal COX-2 expression. These results indicate that COX-2 upregulation is a specific finding of active LN and that monocytes infiltrating the glomeruli contribute to the exaggerated local synthesis of TXA2. If this is correct, COX-2 may soon become a target for therapeutic intervention in this disease.

Preparation of Pd/C catalysts via ultrasound: a study of the metal distribution

Palladium supported on active carbon catalysts was prepared using ultrasound during one of the preparation steps. An investigation of the metal distribution into the pores of the support was performed both by a deep characterization of the prepared samples and by a catalytic reaction involving some organic reactants to be reduced.

Early ganciclovir therapy effectively controls viremia and avoids the need for cytomegalovirus (CMV) prophylaxis in renal transplant patients with cytomegalovirus antigenemia

Cytomegalovirus (CMV) infection is still a problem for organ transplant recipients despite studies that long-term prophylaxis with high dose of acyclovir or ganciclovir given to all organ recipients may limit the consequences of infection and disease. In the present report of 160 consecutive renal transplant patients, we used a diagnostic assay for CMV antigenemia (detection of CMV antigen in peripheral blood leukocytes) and treated with ganciclovir only those patients who had a positive test. No patient in this series had routine prophylaxis. Out of 160 patients, 71 had clinical and/or laboratory signs of infection, and were tested for early antigen in peripheral leukocytes. The test was positive in 35, all of whom received a course of 3 wk ganciclovir treatment which effectively cured CMV in 34 count of 35. One patient was ganciclovir-resistant, but responded to foscarnet. None of the 36 patients who had no early antigenemia and did not receive treatment developed the disease. The treatment was extremely well tolerated in all our patients with no adverse events. Thus, even though this was not a controlled study, our present results may be taken to indicate that long-term acyclovir or ganciclovir for all organ transplant recipients might be no longer totally justified. We conclude that detecting viral antigen in circulating leukocytes identifies patients who are indeed at risk of developing severe CMV disease. When these patients are treated early enough, CMV is eliminated with a relatively short course of ganciclovir, which has virtually no side effects.