ABSTRACT
Pancreatic stroma plays an important role in the induction of pancreatic cells by the use of close range signaling. In this respect, we presume that pancreatic mesenchymal cells [PMCs] as a fundamental factor of the stromal niche may have an effective role in differentiation of umbilical cord blood cluster of differentiation 133[+] [UCB-CD133[+]] cells into newly-formed beta-cells in vitro. This study is an experimental research. The UCB-CD133[+] cells were purified by magnetic activated cell sorting [MACS] and differentiated into insulin producing cells [IPCs] in co-culture, both directly and indirectly with rat PMCs. Immunocytochemistry and enzyme linked immune sorbent assay [ELISA] were used to determine expression and production of insulin and C-peptide at the protein level. Our results demonstrated that UCB-CD133[+] differentiated into IPCs. Cells in islet-like clusters with [out] co-cultured with rat pancreatic stromal cells produced insulin and C-peptide and released them into the culture medium at the end of the induction protocol. However they did not respond well to glucose challenges. Rat PMCs possibly affect differentiation of UCB-CD133[+] cells into IPCs by increasing the number of immature beta-cells
ABSTRACT
Hepatitis B vims [HBV] infection in patients who lack detectable hepatitis B surface antigen [HBsAg] is called occult hepatitis B infection. Such infections have been frequently identified in patients with chronic hepatitis C liver disease, but their prevalence is not known.207 patients with chronic hepatitis C who were HCV-RNA and anti-HCV positive were studied for HBV-DNA by PCR, and for HBsAg and anti-HBc by ELIS A. DNA was extracted by high pure nucleic acid kit [Roche-Germany]. HB V-DNA amplification was done with a set of primer directed to the pre-S region. HBsAg and anti-HBc were evaluated by a commercially available ELIS A kit [Dade Behring].23 of 207 patients with chronic hepatitis C liver disease [11.1%] were positive for HB V-DNA [co-infection]. Among this group 17 patients [8.2%] were HBsAg negative [occult infection]. 8 of 17 patients with occult infection [47%] were anti-HBc positive and 9 were anti-HBc negative [53%]. No significant difference was found in epidemiological and biochemical parameters in patients with HCV alone in comparison with HCV co-infected with occult hepatitis B [p= 0.453 for ALT and77= 0.498 for AST]. Occult hepatitis B virus infections occur frequently in patients with chronic hepatitis C liver disease and may have clinical significance
ABSTRACT
Apoptosis, or active cell death, is a specific mode of cell death, which is characterized by morphological changes such as chromatin condensation, fragmentation of the nucleus, cytoplasmic retraction and appearance of apoptotic bodies' containing apparently intact organelles. Apoptosis occurs in physiological conditions as a regulatory mechanism of tissue growth, where cell proliferation is balanced. The aim of this research was to study the ability of Fas to initiate apoptosis in vitro before and after treatment with Cytarabin on tissue culture and to correlate the response. The human leukemia and normal cells were treated with cytarabin in tissue culture, and apoptotic treated cells were estimated by flow cytometry and phosphatidylserines kit. The results were analyzed by statistical tests [post hoc]. From these data, it was found that Fas antigen was expressed in all cases, but the expression level varied widely. Apoptosis and also Fas antigen expression in short term cell culture were higher in media containing drug than in media without drug; but there had been no reasonable correlation between percentage of Fas antigen and apoptosis responses before culture. Expression of Fas antigen was low in most of the leukemic cells and the preliminary results showed that increase in Fas antigen expression [above 20%] after treatment, was a favorable prognostic outcome. It is associated with increase relapse, free and total survival. In addition, using this antigen as a chemotherapic and immunotherapic target, would initiate a new strategy for treatment of leukemia [chemotherapy and immunotherapy]
ABSTRACT
Regulation of normal cell growth and turnover is balanced between cell proliferation, cell differentiation and apoptosis. A disruption of this balance is thought to be an important event leading to carcinogenesis .One of the effector molecules in apoptosis is Fas antigen. Crosslinking of Fas by its ligand [Fas L] or agonistic anti Fas antibodies induces apoptosis of cells expressing Fas on the membrane by triggering cascade of caspaces. The aim of this research was to study the percent of expression of Fas antigen on bone marrow and peripheral blood cells in 100 patients suffering from acute lymphoid and myeloid leukemia by flowcytometry method. Sample were obtained at the time of diagnosis before antileukemic therapy. Expression of Fas antigen on normal control peripheral leukocytes was also analysed. From these data, it was found that Fas antigen is expressed in all cases, but the expression level varied widely. The percentage of Fas antigen expression in all of acute lymphoid leukemia samples was below 20%, but in acute myeloid leukemia samples, 8 out of 50 cases was above 20%. In normal control samples, the mean value for monocytes was higher than granulocytes and in granulocytes higher than lymphcytes. Expression of Fas antigen in most of the leukemic cells was low and the preliminary results showed that increase in Fas antigen expression above 20% after treatment, is a favorable prognostic sign associated with increase relapse free and total survival. Thus evaluation of this antigen before, during and after treatment is recommended
Subject(s)
Humans , Male , Female , fas Receptor , Leukemia , Flow Cytometry , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Leukemia, MyeloidABSTRACT
In chronic myelogenous leukemia [CML], the mature granulocytes originate from a stem cell line harboring an abnormal chromosome, therefore it is possible that metabolic-functional abnormalities occur in the morphologically mature cells. In the present study, the phagocytic activity including intracellular killing, nitro blue tetrazolium [NBT] reduction, and phagocytosis were studied in 37 CML patients in different stages of the disease. The results were compared with those of 37 normal controls. Patients' neutrophils display significantly lower intracellular killing [P<0.01], NBT reduction [P<0.01] and phagocytosis [P<0.001] than that of normal controls. Analysis of the results revealed an inverse correlation between phagocytic activity and leukocyte count or percentage of immature cells [r = -0.3, P<0.01]. In conclusion, the results indicate that neutrophils of CML patients have impaired phagocytic activity. This defect is more prominent in patients in blastic phase, whereas patients in remission show normal values