Detection of t(9;22) b2a2 fusion transcript by flow cytometry.

INTRODUCTION: We assessed the feasibility of flow cytometry-fluorescent in situ hybridization technique in the detection of translocated mRNA in the cytoplasm of human peripheral blood nucleated cells. It is assumed that this assay can be applied as a diagnostic method in the detection of chromosomal translocation which commonly occurs in hematologic malignancies. METHODS: KCL-22 cell line and white blood cells from 21 CML patients were recruited in the study. Cells were isolated and fixed. After permeabilization, cells were resuspended in hybridization buffer and probes were added to the mixture. Subsequently, cells were washed and analyzed on the flow cytometer instrument. The flow cytometry results were compared with qRT-PCR and fluorescent microscope outcomes. RESULTS: Using the current principle, 97 ± 2.1% of the KCL-22 cells were labeled with b2a2 mRNA-specific probes. In addition, seven patients were recognized positive for t(9;22) b2a2. The percentage of cells containing abovementioned translocation in these patients was varied from 3.26% to 97.8%. There was no false-positive result in negative controls (K562 with BCR-ABL1 b3a2, NB4, and Jurkat cell lines) along with blood samples of normal controls. All the results obtained by flow-FISH were confirmed by qRT-PCR and fluorescent microscope. CONCLUSION: This strategy benefits from appropriate specificity, sensitivity, rapidity, and ability in the determination of malignant cell percentage. Therefore, it can improve traditional time-consuming and labor-intensive FISH method.

Construction of bacterial ghosts for transfer and expression of a chimeric hepatitis C virus gene in macrophages.

The bacterial ghost (BG) production is a field of biotechnology for applications in vaccine and drug delivery. We assessed the capacity of BG for delivery of a recombinant gene encoded for both cell mediated and antibody dependent epitopes of hepatitis C virus (HCV) into murine macrophages. Escherichia coli (E. coli) cells were transformed with the lysis plasmid (pHH43). To produce chimeric gene, NS3 (non-structural protein 3) and core regions of HCV genome were fused together by splicing by overlap extension (SOEing) PCR and were cloned into plasmid pEGFP-C1. Bacterial ghosts were loaded with recombinant pEGFP-C1 and then were transferred to murine macrophages (RAW 264.7). To investigate plasmid transfection and chimeric mRNA transcription, fluorescent microscopy and RT-PCR were used. In vitro studies indicated that bacterial ghosts loaded with pEGFP-C1 plasmid were efficiently taken up by murine macrophages and indicated a high transfection rate (62%), as shown by fluorescent microscopy. RT-PCR from extracted intracellular mRNAs for chimeric Core-NS3 gene showed a specific 607 bp fragment of the gene. The sequence analysis of purified PCR products demonstrated the expected unique mRNA sequence. We constructed a chimeric HCV gene containing both cell mediated and antibody dependent epitopes with a significant expression in murine macrophages delivered by bacterial ghost.

Effect of 900 MHz Electromagnetic Radiation on the Induction of ROS in Human Peripheral Blood Mononuclear Cells.

BACKGROUND: Despite numerous studies over a decade, it still remains controversial about the biological effects of RF EMF emitted by mobile phone telephony. OBJECTIVE: Here we investigated the effect of 900 MHz GSM on the induction of oxidative stress and the level of intracellular reactive oxygen species (ROS) in human mononuclear cells, monocytes and lymphocytes as defence system cells. METHOD: 6 ml Peripheral Blood samples were obtained from 13 healthy volunteers (21-30 year-old). Each sample was devided into 2 groups: one was exposed RF radiation emitted from a mobile phone simulator for 2 hour and the other used as control group which was not exposed to any fields. After that, mononuclear cells were isolated from peripheral blood by density gradient centrifugation in Ficoll-Paque. The intracellular ROS content in monocytes and lymphocytes was measured by the CM-H2DCFDA fluorescence probe using flowcytometry technique. RESULTS: Our results showed significant increase in  ROS production after exposure in population rich in monocytes. This effect was not significant in population rich in lymphocytes in comparison with non exposed cells. CONCLUSION: The results obtained in this study clearly showed the oxidative stress induction capability of RF electromagnetic field in the portion of PBMCs mostly in monocytes, like the case of exposure to micro organisms, although the advantages or disadvantages of this effect should be evaluated.