Endovascular repair of abdominal aortic aneurysms with concomitant common iliac artery aneurysm: outcome analysis of the EUROSTAR Experience

BACKGROUND: To compare outcomes following endovascular repair in abdominal aortic aneurysm (AAA) patients with and without concomitant iliac artery aneurysm disease. METHODS: Data on patient characteristics and risk factors, aneurysm morphology, interventional details, complications, and mortality were retrieved from the EUROSTAR registry database for the period from October 1996 to November 2006. AAA patients without concomitant iliac aneurysm disease (group I, n = 6286) were compared to 1268 patients with aneurysmal iliac vessels (group II) regarding mortality, device-related complications, and need for secondary interventions. Logistic regression and Cox proportional hazards model were performed to assess independent associations with outcome parameters in the study groups. RESULTS: Group II had more patients classified as ASA III or IV (55.1% versus 50.3% in group I; p = 0.002); they were more frequently unfit for open aortic repair (30.3% versus 23.4%; p<0.0001) and had larger-diameter aneurysms (62.3 versus 60.7 mm; p<0.0001) and infrarenal necks (24.5 versus 24.1 mm; p<0.001). In addition, group II patients had a higher rate of internal iliac artery occlusion (11.4% versus 5.2%; p<0.0001) and more significant angulation of the aortic neck (30.8% versus 24.3%; p<0.0001) and iliac artery (48.3% versus 41.9%; p<0.0001). Group II patients had higher 5-year cumulative incidences of distal type I endoleaks (9.1% versus 4.3%; p<0.0001), iliac limb occlusion (5.9% versus 4.4%; p = 0.040), secondary transfemoral intervention (17.6% versus 8.9%; p = 0.019), and aneurysm rupture (4.5% versus 1.7%; p = 0.042). CONCLUSION: Although aneurysm-related mortality and mortality from other causes were similar in both study groups, concomitant iliac artery aneurysms in AAA patients were associated with an increased incidence of distal type I endoleak, iliac limb occlusion, and aneurysm rupture. Therefore, caution is warranted, and efforts should be made to avoid procedural mishaps.     

An animal model for human cellular immunotherapy: specific eradication of human acute lymphoblastic leukemia by cytotoxic T lymphocytes in NOD/scid mice

Adoptive immunotherapy using in vitro-generated donor-derived cytotoxic T lymphocytes (CTLs) can be effective in the treatment of relapsed leukemia after allogeneic transplantation. To determine effector cell characteristics that result in optimal in vivo antileukemic efficacy, we developed an animal model for human CTL therapy. Nonobese diabetic/severe combined immunodeficiency (NOD/scid) mice were inoculated with either of 2 primary human acute lymphoblastic leukemia (ALL), denoted as SK and OF. Anti-SK and anti-OF CTLs were generated in vitro by repeated stimulation of donor peripheral blood mononuclear cells with either SK or OF cells. Both CTL lines displayed HLA-restricted reactivity against the original targets and non-major histocompatibility class (MHC)-restricted cross-reactivity in vitro. The CTLs were administered intravenously weekly for 3 consecutive weeks to mice engrafted with either SK or OF leukemia. In 3 of 8 SK-engrafted and anti-SK-treated mice, complete remissions were achieved in blood, spleen, and bone marrow. In the remaining 5 animals partial remissions were observed. In 4 of 4 OF-engrafted anti-OF-treated mice partial remissions were observed. The antileukemic effect of specific CTLs was exerted immediately after administration and correlated with the degree of HLA disparity of the donor-patient combination. In cross-combination-treated animals, no effect on leukemic progression was observed indicating that in vivo antileukemic reactivity is mediated by MHC-restricted effector cells. The CTLs, however, displayed an impaired in vivo proliferative capacity. Ex vivo analysis showed decreased reactivity as compared to the moment of infusion. We therefore conclude that the model can be used to explore the requirements for optimal in vivo efficacy of in vitro- generated CTLs.     

New CFSE-based assay to determine susceptibility to lysis by cytotoxic T cells of leukemic precursor cells within a heterogeneous target cell population

For the clinical evaluation of the efficacy of cellular immunotherapy it is necessary to analyze the effector functions of T cells against primary leukemic target cell populations which are usually considerably heterogeneous caused by differential maturation stages of the leukemic cells. An appropriate assay should not only allow the quantitative analysis of rapid cell death induction as measured by the conventional 51Cr release assay but also of the more slowly executing pathways of T-cell-induced apoptosis occurring within days instead of hours which cannot be measured using this method. Furthermore, it should dissect the differential susceptibility to T-cell-induced cell death of various target cell subpopulations and characterize the malignant precursor cells capable of producing malignant progeny. To fulfill these requirements we developed a new assay based on carboxyfluorescein diacetate succinimidyl ester (CFSE) labeling of the target cell population combined with antibody staining of specific cell populations and addition of fluorescent microbeads to quantitatively monitor target cell death occurring within a longer time frame up to at least 5 days. This new assay facilitates the analysis of differential recognition of distinct cell types within a heterogeneous target cell population and allows simultaneously evaluation of the proliferative status of surviving target cells in response to relevant cytokines.     

Effects of CCR5-Delta32 and CCR2-64I alleles on HIV-1 disease progression: the protection varies with duration of infection

OBJECTIVE: To examine temporal variation in the effects of CCR5-Delta32 and CCR2-64I chemokine receptor gene polymorphisms on HIV-1 disease progression. DESIGN: Pooled analysis of individual patient data from 10 cohorts of HIV-1 seroconverters from the United States, Europe, and Australia. METHODS: We studied HIV-1 seroconverters of European (n = 1635) or African (n = 215) ancestry who had been genotyped for CCR5-Delta32 and CCR2-64I. We used Cox proportional hazards models with time-varying coefficients to determine whether the genetic protection against AIDS (1987 case definition) and death varied with time since seroconversion. RESULTS: Protection against AIDS conferred by CCR5-Delta32 held constant at a 31% (RH 0.69, 95% CI 0.54, 0.88) reduction in risk over the course of HIV-1 infection, whereas protection against death held constant at a 39% reduction in risk (RH 0.61, 95% CI 0.45, 0.88). When the period from AIDS to death was isolated, the survival benefit of CCR5-Delta32 diminished 2 years after AIDS. Protection against AIDS conferred by CCR2-64I was greatest early in the disease course. Compared with individuals without CCR5-Delta32 or CCR2-64I, individuals with one or two copies of CCR2-64I had a 58% lower risk of AIDS during the first 4 years after seroconversion (RH 0.42, 95% CI 0.23, 0.76), a 19% lower risk during the subsequent 4 years (RH 0.81, 95% CI 0.59, 1.12), and no significant protection thereafter. CONCLUSION: The protection against AIDS provided by CCR5-Delta32 is continuous during the course of infection. In contrast, the protection provided by CCR2-64I is greatest early in the course of infection.     

Dose- and time-dependent gene expression alterations in prostate and colon cancer cells after in vitro exposure to carbon ion and X-irradiation

Hadrontherapy is an advanced form of radiotherapy that uses beams of charged particles (such as protons and carbon ions). Compared with conventional radiotherapy, the main advantages of carbon ion therapy are the precise absorbed dose localization, along with an increased relative biological effectiveness (RBE). This high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. Currently, hadrontherapy is being used for the treatment of specific types of cancer. Previous in vitro studies have shown that, under certain circumstances, exposure to charged particles may inhibit cell motility and migration. In the present study, we investigated the expression of four motility-related genes in prostate (PC3) and colon (Caco-2) cancer cell lines after exposure to different radiation types. Cells were irradiated with various absorbed doses (0, 0.5 and 2 Gy) of accelerated ¹³C-ions at the GANIL facility (Caen, France) or with X-rays. Clonogenic assays were performed to determine the RBE. RT-qPCR analysis showed dose- and time-dependent changes in the expression of CCDC88A, FN1, MYH9 and ROCK1 in both cell lines. However, whereas in PC3 cells the response to carbon ion irradiation was enhanced compared with X-irradiation, the effect was the opposite in Caco-2 cells, indicating cell-type–specific responses to the different radiation types.     

Ganciclovir-mediated elimination of HSV-Tk+ T cells and cure of graft-vs-host disease in an allogeneic bone marrow transplantation model in the rat

OBJECTIVE: Suicide gene therapy for leukemia aims to benefit from T cells in the BM graft, by reducing the probability of leukemia relapse (GVL), while severe complications of graft-vs-host disease (GVHD) may be avoided. In an allogeneic rat BMT model we defined the conditions to induce a lethal GVHD with HSV-Tk gene-transduced T cells. We studied the feasibility to rescue the animals by conditional elimination of the T cells with ganciclovir (GCV) treatment. METHODS: Allogeneic T cells transduced with a retroviral vector encoding the HSV-Tk suicide gene were added in varying numbers to a BM graft. Expression of HSV-Tk strongly increases the cytolytic effect of GCV, thereby allowing elimination of overreactive T cells at will. Various experimental conditions were tested in the rat model. RESULTS: A relation between the number of HSV-Tk(+) T cells added to the BM graft and GVHD development was found. GCV treatment resulted in selective HSV-Tk(+) T-cell elimination in blood and tissues but not in abrogation of GVHD due to persistence of HSV-Tk(-) T cells. T cells in unmanipulated rat BM normally have a low risk to induce GVH but when they are administered in combination with high numbers of HSV-Tk(+) T cells there is an apparent increase in their GVH-inducing potential. When HSV-Tk(+) T cells are added to T cell-depleted BM a consequently developing GVH can be controlled by GCV treatment with 60-70% of the animals surviving. CONCLUSIONS: We show that T cell-mediated suicide gene therapy within the context of allo-BMT can be applied with success. The apparent limitation in the number of transduced as well as nontransduced T cells that can be safely added to the BM graft should be taken into consideration when designing human suicide gene therapy protocols.