Optimizing the recovery of peripheral blood mononuclear cells trapped in leukoreduction filters - A comparison study

Abstract Introduction The isolation of captured peripheral blood mononuclear cells (PBMNCs) from leukoreduction filters (LRFs) can be of great importance in terms of bringing the lost cells back into use. Objective The aim of this study was to evaluate various methods based on their potential to recover the peripheral blood cells from LRFs with a focus on mononuclear cells (MNCs). Method For cell isolation from LRFs, three distinct methods (back-flushing, direct and vacuum pump) were compared through the calculation of the yield of isolated MNCs. The viability of extracted cells was determined by the flow cytometry technique. Moreover, the recovered MNCs were characterized regarding the presence of blood stem cell purification. The cell culture, microscopic observation, and immunophenotyping were employed to characterize the blood stem cells (hematopoietic, mesenchymal and progenitor endothelial stem cells). Results The yield of isolation obtained in the back-flushing, direct and vacuum pump methods were 17.7 ± 1.28, 17.3 ± 0.96 and 21.2 ± 0.90 percent, respectively. Although the highest potential for total blood cell recovery belonged to the vacuum pump method, the lowest cell viability (85.73 ± 4.84%) was observed in this method. However, the isolation process of the back-flushing and direct methods had less effect on cell viability. The characterization of the isolated MNCs displayed that the dominant positive phenotype was for CD34/CD45, indicating hematopoietic stem cells. In addition, the endothelial stem/progenitor cells were significantly detected as CD31/CD133 positive cells. Conclusion According to our results and considering the safety and efficiency potential of each of the applied methods, the back-flushing in comparison with the other methods can be considered a suitable procedure for MNC isolation from LRFs.

Optimizing the recovery of peripheral blood mononuclear cells trapped in leukoreduction filters - A comparison study.

INTRODUCTION: The isolation of captured peripheral blood mononuclear cells (PBMNCs) from leukoreduction filters (LRFs) can be of great importance in terms of bringing the lost cells back into use. OBJECTIVE: The aim of this study was to evaluate various methods based on their potential to recover the peripheral blood cells from LRFs with a focus on mononuclear cells (MNCs). METHOD: For cell isolation from LRFs, three distinct methods (back-flushing, direct and vacuum pump) were compared through the calculation of the yield of isolated MNCs. The viability of extracted cells was determined by the flow cytometry technique. Moreover, the recovered MNCs were characterized regarding the presence of blood stem cell purification. The cell culture, microscopic observation, and immunophenotyping were employed to characterize the blood stem cells (hematopoietic, mesenchymal and progenitor endothelial stem cells). RESULTS: The yield of isolation obtained in the back-flushing, direct and vacuum pump methods were 17.7 ±â€¯1.28, 17.3 ±â€¯0.96 and 21.2 ±â€¯0.90 percent, respectively. Although the highest potential for total blood cell recovery belonged to the vacuum pump method, the lowest cell viability (85.73 ±â€¯4.84%) was observed in this method. However, the isolation process of the back-flushing and direct methods had less effect on cell viability. The characterization of the isolated MNCs displayed that the dominant positive phenotype was for CD34/CD45, indicating hematopoietic stem cells. In addition, the endothelial stem/progenitor cells were significantly detected as CD31/CD133 positive cells. CONCLUSION: According to our results and considering the safety and efficiency potential of each of the applied methods, the back-flushing in comparison with the other methods can be considered a suitable procedure for MNC isolation from LRFs.

Expression and CpG island methylation pattern of MMP-2 and MMP-9 genes in patients with congenital factor XIII deficiency and intracranial hemorrhage.

OBJECTIVES: Congenital factor XIII (FXIII) deficiency is a rare severe bleeding disorder. Intracranial hemorrhage (ICH) is the leading cause of mortality and morbidity in FXIII deficiency. However, its pathogenesis is not well understood yet. In this study, we investigated the expression and CpG island methylation status of matrix metalloproteinase-2 (MMP-2) and MMP-9 in patients with FXIII deficiency and ICH. METHODS: Forty patients with FXIII deficiency including twenty patients with ICH, and twenty without ICH were recruited as case and control groups, respectively. Methylation status was determined by bisulfite sequencing polymerase chain reaction (PCR), and gene expression was assessed by quantitative real-time PCR. RESULTS AND DISCUSSION: We found an unmethylated pattern for both MMP-2 and MMP-9 genes in the case group. Both genes were partially methylated in the control group, while the percentage of methylated CpGs was significantly higher in MMP-9 than MMP-2 (P = 0.001). Furthermore, higher expression of MMP-9 (in both the mRNA and protein levels) was found in the case than control group (P = 0.008 and P = 0.009, respectively). On the other hand, there was no significant difference in MMP-2 expression level (neither mRNA nor protein) between the two groups (P = 0.12 and P = 0.25, respectively). CONCLUSION: Our findings indicated that MMP-9 over-expression might be related to ICH in FXIII deficiency, and gene methylation effectively regulates its expression. Future researches will expand our understanding of the pathogenesis of ICH in congenital FXIII deficiency.

Upregulation of miR-210 promotes differentiation of mesenchymal stem cells (MSCs) into osteoblasts.

Numerous studies indicated that microRNAs are critical in the regulation of cellular differentiation, by controlling the expression of underlying genes. The aim of this study was to investigate the effect of miR-210 upregulation on differentiation of human umbilical cord blood (HUCB)-derived mesenchymal stem cells (MSCs) into osteoblasts. MSCs were isolated from HUCB and confirmed by their adipogenic/osteogenic differentiation and flow cytometric analysis of surface markers. Pre-miR-210 was amplified from human DNA, digested and ligated with plenti-III-mir-green fluorescent protein (GFP) vector, and cloned in STBL4 bacteria. After confirmation with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), the plenti-III-GFP segment bearing pre-miR-210 was transfected into MSCs by electroporation. Two control vectors, pmaxGFP and Scramble, were transfected separately into MSCs. The expression of miR-210 and genes related to osteoblast differentiation, i.e., runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and osteocalcin gene, in the three groups of transfected MSCs was analyzed 0, 7, 14, and 21 days of transfection by quantitative reverse transcription PCR (qRT-PCR). Overexpression of miR-210 was observed in MSCs transfected with miR-210-bearing plasmid, and this was significantly different compared to Scramble group (p < 0.05). Significantly increased expression of Runx2 (at day 7 and 14), ALP and osteocalcin genes (at all time points for both genes) was observed in MSCs with miR-210-bearing plasmid compared to controls. Overall, the overexpression of miR-210 in MSCs led to MSC differentiation into osteoblasts, most probably by upregulating the Runx2, ALP, and osteocalcin genes at different stages of cell differentiation. Our study confirms the potential of miRNAs in developing novel therapeutic strategies that could target regulatory mechanisms of cellular differentiation in various disease states.

Study of the Relationship between HPA-1 and HPA-5 Gene Polymorphisms and Refractory to Platelet Therapy and Recombinant Factor VII in Glanzmann Thrombasthenia Patients in Southeast of Iran.

Background: Glanzmann Thrombasthenia (GT) is a rare autosomal disease. HPA (Human Platelet Alloantigen) is a surface polymorphic alloantigen of platelets. This study was intended to investigate and compare the polymorphism of HPA-1 and HPA-5 genes in two groups of GT patients, with and without resistance to platelet and recombinant factor VII therapy. Materials and Methods: This case control study was performed on GT patients (n=16) with resistance to platelet therapy and recombinant factor VII and control group of GT patients (n=16) without resistance to platelet therapy and recombinant factor VII. The consent form was completed by each patient. Gene polymorphisms of HPA-1 and HPA-5 were investigated using SSP-PCR, and the obtained data were analyzed using statistical software SPSS16.0. Results: The results indicated no significant relationship between the studied genes and their resistance to platelet therapy and recombinant factor VII. The frequencies of HPA-1 genotype a/a were 98% and 94% in patient and control groups, respectively. The frequency of allele b was found to be less than allele a. The value of this allele was 4% in patient group and 1% in control group. In addition, the HPA-5a/a (98%) was the most frequent alloantigen?? (check it) in both groups. Seven percent (7%) of the patients had the HPA-5a/b genotype, and the HPA-5b/b was found to be absent in these individuals. Conclusion: According to the results obtained, it could be concluded that these genes play no role in resistance to platelet therapy.

The Role of MicroRNAs in Myeloproliferative Neoplasia.

MiRs are 17-25 nucleotide non-coding RNAs. These RNAs target approximately 80% of protein coding mRNAs. MiRs control gene expression and altered expression of them affects the development of cancer. MiRs can function as tumor suppressor via down-regulation of proto-oncogenes and may function as oncogenes by suppressing tumor suppressors. Myeloproliferative neoplasias (formerly known as chronic myeloproliferative disorders) form a class of hematologic malignancies demonstrating the expansion of stem cells in one or more hematopoietic cell lines. CML results from an acquired translocation known as BCR-ABL (Philadelphia chromosome). JAK2V617F mutation is present in over 95% of PV, 55% of ET and 65% of PMF cases. Aberrant expression of miR is associated with myeloproliferative neoplasias, pathogenesis, disease progress and response to treatment. MiRs can also be potential therapeutic targets. CML is mainly treated by tyrosine kinase inhibitors such as Imatinib. In addition, altered function of miRs may be used as a prognostic factor in treatment. Resistance to Imatinib is currently a major clinical problem. The role of a number of miRs has been demonstrated in this resistance. Changing expression pattern of miRs can be effective in response to treatment and inhibition of drug resistance. In this paper, we set out to evaluate the effect of miRs in pathogenesis and treatment of MPN.

Central nervous system bleeding in pediatric patients with factor XIII deficiency: a study on 23 new cases.

BACKGROUND: Factor XIII (FXIII) deficiency is an extremely rare bleeding disorder, which has the highest incidence in Sistan and Baluchistan Province in Iran, compared to its overall incidence around the world. This disorder has different clinical manifestations ranging from mild bleeding tendency to lethal bleeding episodes including central nervous system (CNS) hemorrhage. The aim of this study was to evaluate the demographic data, pattern of CNS bleeding, and the role of plasminogen activator inhibitor-1 (PAI-1) (PAI-1) 4G/5G and thrombin activatable fibrinolysis inhibitor (TAFI) Thr325Ile polymorphisms in intracranial and extracranial hemorrhages in 23 new cases of FXIII-deficient subjects. METHODS: This case-control study was conducted on 23 FXIII-deficient patients with CNS bleeding episodes and 23 patients as the control group with FXIII deficiency but without any history of CNS bleeding. Initially, to confirm the molecular defect, both groups were evaluated for the most frequently reported mutation of FXIII (Trp187Arg mutation) in a previous study in Sistan and Baluchistan Province. Then, demographic data, clinical manifestations, and pattern of CNS bleeding were determined. Eventually, the patients were assessed for PAI-14G/5G and TAFI Thr325Ile polymorphisms. RESULTS: The results of this study revealed that all the subjects (including the case and control groups) were homozygous for Trp187Arg mutation. Nineteen patients (82.6%) had intracranial hemorrhage (ICH) and four patients (17.4%) had extracranial hemorrhage (ECH). Intraparenchymal hemorrhage was the most common form of ICH (89.5%), and epidural hemorrhage was observed in two patients (10.5%). Anatomic regions in patients with intraparenchymal hemorrhage were temporal in six (35.3%), occipital in four (23.5%), diffused intraparenchymal in four (23.5%), temporal-occipital in two (11.8%), and subdural with temporal in one (5.9%) patient. We found that in the case group, 14 patients (60.8%) were homozygous for TAFI Thr325Ile polymorphism and 8 cases (34.7%) were heterozygous. In the control group, 4 (17.4%) and 13 (56.5%) patients were homozygous and heterozygous, respectively (P < 0.001 vs. P < 0.01).We also found that an equal number of patients (two individuals) in the case and control groups (8.7% in each group) were heterozygous for PAI-14G/5G polymorphism. CONCLUSION: It seems that PAI-14G/5G polymorphism does not have any effect on occurrence of ICH and ECH in patients with FXIII deficiency, while TAFI Thr325Ile is a strong genetic risk factor (odds ratio:14.9, 95% confidence interval: 7.4-31.1).