The effect of CD34 count and clonogenic potential of hematopoietic stem cells on engraftment.

In this study we have determined that the number of the CD34 (+) cells in the grafts that were infused to 48 patients who underwent autologous and allogeneic hematopoietic cell transplantation and evaluated the number of colony forming units in vitro. Our aim was to determine whether there is a relation between these cell counts and post transplantation engraftment kinetics. A negative correlation was detected (p<0.05) between the CD34 (+) cell count and all colony forming units. A correlation between the CD34 (+) cell count and the kinetics of engraftment could not be demonstrated. In the autologous group, only a weak negative correlation between the CFU-GEMM and neutrophil engraftment was detected. In the allogeneic group, colony forming units did not determine the engraftment.

The effect of extracorporeal photoimmunotherapy (ECP) on serum TNF-a level in chronic graft versus host disease (GvHD).

Graft versus host disease (GvHD) is the most prominent cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (Allo-HCT). Extracorporeal photoimmunotherapy (ECP) is an alternative therapeutic modality in steroid and/or cyclosporin-A refractory GvHD developing after Allo-HCT. The aim of this study was to evaluate whether there was any relation between serum TNF-a levels and the response to ECP in patients with steroid refractory of extensive chronic GvHD. Between March 2001 and August 2003, seven patients (male: 1, female: 6) had ECP for treatment of steroid refractory extensive chronic GvHD. Five age and gender matched healthy volunteers were included in this study as the control group. The age of the patients ranged from 18 to 49 years. All patients were allografted from HLA-identical sibling donors. The median number of ECP sessions was 10 (8-36), consisting of two sequential cycles monthly. For measurement of serum TNF-a levels, blood samples were obtained both prior to ECP (basal) and after the first and second in all patients and in five patients after the 10th session. Serum TNF-a levels (Quantakine HS, R&D system, UK) were measured in peripheral venous blood samples by an ELISA method. ECP was given at a median of 5.8 months (1-14 months) after allo-HCT. No complications were seen during or after the ECP procedures. The median time of an ECP session was 183 minutes. The median volume of Uvadex used per session was 4.40 ml (3.61-5.61). The basal mean level of TNF-a was higher in patients than in the control group (2.47+/-0.83 pg/ml vs. 1.75+/-0.06, p=0.05). The mean TNF-a levels decreased from 2.47+/-0.83 pg/ml to 1.77+/-0.93 pg/ml after the initial session (p=0.045) and from 2.32+/-0.92 pg/ml to 1.69+/-0.93 pg/ml after the second day (p=0.015). After completion of the ECP sessions, extensive chronic GvHD recovered in only three patients. In three clinically responsive patients, the TNF-a levels were significantly reduced after both the second and tenth sessions. In contrast, in two patients not responding to ECP therapy, TNF-a levels were increased. In order to report whether these changes in TNF levels is an early predictor for evaluation of the efficacy of ECP in extensive chronic GvHD, TNF-a levels should be studied in a larger series.

Impact of harvest product volume in erythrocyte depletion of allogeneic or autologous bone marrow using COBE spectra.

UNLABELLED: Depletion of bone marrow (BM) from erythrocytes is used to prevent early hemolysis in major ABO incompatible allogeneic hematopoietic cell transplantation (Allo-HCT). This method was also strongly recommended before storing of autologous and even allo-BM for volume reduction in order to prevent early hemolysis and DMSO toxicity after infusion. In our center, erythrocyte depletion of BM harvests has been performed on a continuous flow cell separator, which used a closed system with a high mononuclear cell (MNC) yield and low rate of erythrocyte contamination. According to the protocol of a cellular therapy approach in a cardiovascular collaborative study we have to adopt the process to lower volumes. We aimed to compare our results with standard volume (SV) (historical control) to low volume ED procedures. PATIENTS AND METHOD: Data has been collected from the last five years. We analyzed 28 cases in the SV group (BM volume >750ml) and 39 cases in the low volume (LV) group. Nineteen of these cases were allogeneic, and 48 were autologous procedures. We used the software COBE PBSC coll vers 5.1 and a standard disposable set (Gambro BCT, Lakewood, USA) for the procedure, and simultaneously, a double bag system with intermediate connectors were used to overcome re-circulation (COBE Spectra Bone Marrow Processing Set, Lakewood USA). RESULTS: The mean volume reduction was 88% (range, 84.4-93.5%) for SV and 90.8% (range, 87.2-91.3%) for the LV group. We did not find any significant difference for MNC yield, volume reduction rate and CD34+ cell recovery between the SV and LV group. There were no complications experienced with regards to device or technical difficulties during procedures. Acute massive intravascular hemolysis was not observed in allogeneic recipients. CONCLUSION: ED and volume reduction with COBE spectra produced successful results in standard and low harvest volumes. This process can be successfully applied to lower volumes and comparable results to the SV harvest can be achieved for the ED rate, reduction of volume and recovery of MNCs and CD34+ cells.

Effects of replacement fluids used for therapeutic plasma exchange on plasma viscosity and plasma oncotic pressure.

INTRODUCTION: Apheresis is a procedure in which one of the components of blood is removed. The aim of therapeutic plasma exchange (TPE) is to remove a large fraction of the patient's plasma from the body, and to exchange this with replacement solutions using automatic devices. With this procedure circulating pathogens and toxins are reduced. Before each TPE results of a baseline basal complete blood count, serum protein electrophoresis, coagulation tests and serum electrolytes must be known. The efficacy of this therapy is assessed only by these values. The proteins responsible for disease may be monoclonal proteins, cryoglobulins, lipoproteins, auto or allo antibodies or toxins. In this study, we aimed to compare the effects of several replacement fluids on plasma viscosity and oncotic pressure. At the same time, we evaluated the correlation between plasma viscosity and oncotic pressure. MATERIAL AND METHODS: 111 TPE were performed on 42 patients. Before TPE, the patients whose veins were not suitable were catheterised either by using a subclavian or jugular 11F dialysis catheter. At each session, approximately 1-1.5L of plasma was exchanged. The procedure was performed with albumin in patients whose albumin was under 3gr/dl. Over this value, the exchange fluids were randomised. RESULTS: When the overall results were analysed, there was no statistically significant difference between groups 1 (HES+albumin) and group 3 (albumin). The statistical difference between group 2 and 3 was significant, but no difference was observed between group 1 and 2. According to the decreasing plasma viscosity, there was a significant difference between group 2 and group 3, but there was no difference between group 1 and group 2. CONCLUSIONS: The replacement solutions used for plasmapheresis are similar when compared for hemorheologic effects, but we have chosen fresh frozen plasma because of fewer side effects.