Comparative analysis of the value of allogeneic hematopoietic stem-cell transplantation in acute myeloid leukemia with monosomal karyotype versus other cytogenetic risk categories

To determine to what extent allogeneic hematopoietic stem-cell transplantation (alloHSCT) quantitatively reduces relapse in acute myeloid leukemia with monosomal karyotype (MK-AML) compared with alternative postremission therapy and how it compares with other cytogenetic subcategories.

[Psychiatric assessment of alcoholic patients on a waiting list for liver transplantation : Which prognostic criteria are empirically proven?]

Liver disorders are the most frequent somatic complications of alcoholism. As 10‑20% of alcoholic patients will develop liver cirrhosis, this is the most frequent reason for premature death in alcoholic patients. Liver transplantation is now an accepted therapy for alcoholic liver cirrhosis but psychiatric assessment is usually required for patients entering a waiting list for transplantation. Prognostic criteria are controversially discussed, especially the so-called 6-month rule. Numerous studies and recent meta-analyses have indicated that duration of alcoholism, family history, age, sex, comorbid substance use and psychiatric disorders, noncompliance and social instability are outcome predictors. The 6-month criterion is not well proven but some studies are indicative. Possible therapeutic interventions for alcoholic patients on a waiting list are discussed.

Cardiac transplantation with hearts from donors after circulatory declaration of death: haemodynamic and biochemical parameters at procurement predict recovery following cardioplegic storage in a rat model

OBJECTIVES: Donation after circulatory declaration of death (DCDD) could significantly improve the number of cardiac grafts for transplantation. Graft evaluation is particularly important in the setting of DCDD given that conditions of cardio-circulatory arrest and warm ischaemia differ, leading to variable tissue injury. The aim of this study was to identify, at the time of heart procurement, means to predict contractile recovery following cardioplegic storage and reperfusion using an isolated rat heart model. Identification of reliable approaches to evaluate cardiac grafts is key in the development of protocols for heart transplantation with DCDD. METHODS: Hearts isolated from anaesthetized male Wistar rats (n = 34) were exposed to various perfusion protocols. To simulate DCDD conditions, rats were exsanguinated and maintained at 37°C for 15-25 min (warm ischaemia). Isolated hearts were perfused with modified Krebs-Henseleit buffer for 10 min (unloaded), arrested with cardioplegia, stored for 3 h at 4°C and then reperfused for 120 min (unloaded for 60 min, then loaded for 60 min). Left ventricular (LV) function was assessed using an intraventricular micro-tip pressure catheter. Statistical significance was determined using the non-parametric Spearman rho correlation analysis. RESULTS: After 120 min of reperfusion, recovery of LV work measured as developed pressure (DP)-heart rate (HR) product ranged from 0 to 15 ± 6.1 mmHg beats min(-1) 10(-3) following warm ischaemia of 15-25 min. Several haemodynamic parameters measured during early, unloaded perfusion at the time of heart procurement, including HR and the peak systolic pressure-HR product, correlated significantly with contractile recovery after cardioplegic storage and 120 min of reperfusion (P < 0.001). Coronary flow, oxygen consumption and lactate dehydrogenase release also correlated significantly with contractile recovery following cardioplegic storage and 120 min of reperfusion (P < 0.05). CONCLUSIONS: Haemodynamic and biochemical parameters measured at the time of organ procurement could serve as predictive indicators of contractile recovery. We believe that evaluation of graft suitability is feasible prior to transplantation with DCDD, and may, consequently, increase donor heart availability.

Intra-Arterial MSC Transplantation Restores Functional Capacity After Skeletal Muscle Trauma

Skeletal muscle trauma leads to severe functional deficits, which cannot be addressed by current treatment options. Our group could show the efficacy of local transplantation of mesenchymal stroma cells (MSCs) for the treatment of injured muscles. While local application of MSCs has proven to be effective, we hypothesized that a selective intra-arterial transplantation would lead to a better distribution of the cells and so improved physiological recovery of muscle function.

Immediate and delayed transplantation of mesenchymal stem cells improve muscle force after skeletal muscle injury in rats

Mesenchymal stem cell (MSC) therapy is a promising approach for regaining muscle function after trauma. Prior to clinical application, the ideal time of transplantation has to be determined. We investigated the effects of immediate and delayed transplantation. Sprague-Dawley rats received a crush trauma to the left soleus muscle. Treatment groups were transplanted locally with 2 × 10(6) autologous MSCs, either immediately or 7 days after trauma. Saline was used as sham therapy. Contraction force tests and histological analyses were performed 4 weeks after injury. GFP-labelled MSCs were followed after transplantation. The traumatized soleus muscles of the sham group displayed a reduction of twitch forces to 36 ± 17% and of tetanic forces to 29 ± 11% of the non-injured right control side, respectively. Delayed MSC transplantation resulted in a significant improvement of contraction maxima in both stimulation modes (twitch, p = 0.011; tetany, p = 0.014). Immediate transplantation showed a significant increase in twitch forces to 59 ± 17% (p = 0.043). There was no significant difference in contraction forces between muscles treated by immediate and delayed cell transplantation. We were able to identify MSCs in the interstitium of the injured muscles up to 4 weeks after transplantation. Despite the fundamental differences of the local environment, which MSCs encounter after transplantation, similar results could be obtained with respect to functional muscle regeneration. We believe that transplanted MSCs residing in the interstitial compartment evolve their regenerative capabilities through paracrine pathways. Our data suggest a large time window of the therapeutical measures.

Progenitor cell recruitment during individualized high-flow, very-large-volume apheresis for autologous transplantation improves collection efficiency

BACKGROUND: Individual adaptation of processed patient's blood volume (PBV) should reduce number and/or duration of autologous peripheral blood progenitor cell (PBPC) collections. STUDY DESIGN AND METHODS: The durations of leukapheresis procedures were adapted by means of an interim analysis of harvested CD34+ cells to obtain the intended yield of CD34+ within as few and/or short as possible leukapheresis procedures. Absolute efficiency (AE; CD34+/kg body weight) and relative efficiency (RE; total CD34+ yield of single apheresis/total number of preapheresis CD34+) were calculated, assuming an intraapheresis recruitment if RE was greater than 1, and a yield prediction models for adults was generated. RESULTS: A total of 196 adults required a total of 266 PBPC collections. The median AE was 7.99 x 10(6), and the median RE was 1.76. The prediction model for AE showed a satisfactory predictive value for preapheresis CD34+ only. The prediction model for RE also showed a low predictive value (R2 = 0.36). Twenty-eight children underwent 44 PBPC collections. The median AE was 12.13 x 10(6), and the median RE was 1.62. Major complications comprised bleeding episodes related to central venous catheters (n = 4) and severe thrombocytopenia of less than 10 x 10(9) per L (n = 16). CONCLUSION: A CD34+ interim analysis is a suitable tool for individual adaptation of the duration of leukapheresis. During leukapheresis, a substantial recruitment of CD34+ was observed, resulting in a RE of greater than 1 in more than 75 percent of patients. The upper limit of processed PBV showing an intraapheresis CD34+ recruitment is higher than in a standard large-volume leukapheresis. Therefore, a reduction of individually needed PBPC collections by means of a further escalation of the processed PBV seems possible.

Mechanisms of airway obliteration after lung transplantation

Post-transplant bronchiolitis obliterans, also called bronchiolitis obliterans syndrome, affects up to 50-60% of patients who survive 5 yr after surgery according to its clinical definition, which is based on the degree of obstructive airway disease. Alloimmune-independent and -dependent mechanisms produce injuries and inflammation of epithelial cells and subepithelial structures, leading to aberrant tissue repair. The triggering of innate immunity by various infections or chemical injuries after, for example, gastroesophageal reflux, may lead to the release of danger signals that are able to activate dendritic cells, a crucial link with adaptive immunity. Inflammation can also increase the expression and display of major histocompatibility alloantigens and thus favor the initiation of rejection episodes. These phenomena may be limited in time and location or may be protracted. Reducing the risk of alloimmune-independent factors may be as important as treating acute episodes of lung rejection. Excessive immunosuppression may be deleterious by increasing the risk of infection, thereby triggering innate and adaptive immunity. New potential therapeutic targets are emerging from the research performed on leukotriene receptors, chemokine receptors, and growth factors. Neutralizing these molecules reduces the initial mononuclear and polynuclear infiltrates or the subsequent fibroproliferative process and the neovascular changes, feeding this process.