[Biological Effects of the SARI Over-expression on K562 Cell Line].

OBJECTIVE: To construct a lentivirus vector carrying SARI gene and to investigate its biological effects on K562 cells. METHODS: SARI was amplified from the plasmid containing SARI cDNA and subcloned into pLOV.CMV.eGFP virus vector. After sequencing, lentivirus packaging, titering, the viruses of SARI-pLOV.CMV.eGFP were harvested and tansfected into the K562 cells. Real-time quantitive PCR and Western blot were performed to validate the SARI expression at the level of mRNA and protein respectively. Simultaneously, the proliferation, apoptosis and cell cycle of K562 cells were detected by CCK-8 and flow cytometry respectively. RESULTS: The SARI overexpressed lentivirus vector was successfully constructed. The mRNA and protein levels of SARI increased significantly in the pLOV.CMV.eGFP-SARI group, which was confirmed by Q-PCR and Western blot; as compared with blank and mock groups, SARI over-expression leaded to significant proliferation inhibition and increased apoptosis of K562 cells, without visible effects on cell cycle. CONCLUSION: the over-expression of SARI gene obviously suppresses the cell proliferation of the K562 cells as well as promotes the apoptosis. The results implied that the induction of the SARI gene expression may be an important candidate therapeutic method for the CML.

Infusions of recipient-derived cytokine-induced killer cells of donor origin eradicated residual disease in a relapsed leukemia patient after allo-hematopoietic stem cell transplantation.

A female patient diagnosed with acute myelocytic leukemia M5a (AML-M5a) relapsed 986 days after her allogeneic peripheral blood stem cell transplantation (allo-PBSCT) from an unrelated male donor with matched human leukocyte antigen (HLA). Three re-induction chemotherapies were administered, and partial remission was achieved. The patient was given repetitive infusion of cytokine-induced killer (CIK) cells expanded from recipient peripheral mononuclear cells of full donor chimerism due to loss of contact of quondam donor for donor lymphocyte infusion (DLI) and rejection of second transplantation. The patient achieved complete cytogenetical remission. This strategy might overcome the obstacle of donor unavailability and present an appealing new therapeutic alternative to donor-recruited adoptive immunotherapy for relapsed disease at post-transplantation.

[Effects of acute myeloid leukemia cell supernatant on the proliferation and apoptosis of CD4+ and CD8+ T cell subsets].

To study the effects of supernatant derived from acute myeloid leukemia (AML) cell lines on proliferation and apoptosis of CD4(+) and CD8(+) T cell subsets and to investigate the mechanism by which AML escapes from immune recognition, lymphocytes were labeled with CFSE and were stimulated with anti-CD3 and anti-CD28 in presence or absence of supernatants from three AML cell lines (HL-60, NB4, U937). After culture, cell suspensions were labeled with 7AAD and CD4 PE (or CD8 PE). Cells were then detected by flow cytometry and their proliferation and apoptosis were analyzed. The results showed that supernatants from two of three cell lines (HL-60 and NB4) inhibited the proliferation of CD4(+) and CD8(+) T cells, and the degree of inhibition showed a dose-dependent way. Similarly, the apoptosis of stimulated CD4(+) T cells was inhibited, but stimulated CD8(+) T cells remained unaffected by supernatant from HL-60 and NB4. In contrary, the apoptosis of proliferative CD8(+) T cells were increased significantly by HL-60 and NB4 supernatant. It is concluded that soluble factors derived from AML cell lines inhibit the proliferation of CD4(+) and CD8(+) T cells and induce the apoptosis of proliferative CD8(+) T cells, that may be one of the mechanisms by which the immunity was suppressed.

[CD4+ CD25high regulatory T cells in peripheral blood of patients with B cell non-Hodgkin's lymphoma].

This study was aimed to analyze the proportion of T cell subsets, CD4(+) CD25(high) regulating T cells (Tr) in peripheral blood of B-NHL patients and their change regularity, and to investigate the immunosuppression mechanism and influence of chemotherapy on immunosuppression function of B-NHL patients. The peripheral blood was collected from 42 patients with B-NHL, 36 patients with B-NHL who achieved partial remission (PR) or complete remission (CR) after 4 - 6 cycles of chemotherapy and 15 healthy controls. By using monoclonal antibodies, the blood samples were evaluated with the flow cytometry for lymphocyte subsets and Tr cells. The results showed that the proportion of CD3(+) and CD4(+) T cells, and the ratio of CD4/CD8 in patients with B-NHL group was significantly less than those in the healthy controls, i.e. (68.33 +/- 15.27)% versus (72.06 +/- 9.26)%; (34.47 +/- 12.84)% versus (42.45 +/- 9.2)%; 1.36 +/- 0.26 versus 1.92 +/- 0.20, but the prevalence of the CD4(+) CD25(high) Tr cells was significantly higher than those in the healthy group [(4.10 +/- 1.21)% versus (2.04 +/- 1.03)%, P < 0.001]. The ratio of CD4/CD8 in chemotherapy group was lower than that in control, but the proportion of CD4(+) CD25(high) Treg cells in chemotherapy group was higher than those before chemo-/radio-therapy and the control. It is concluded that the relative increase of CD4(+) CD25(high) Tr cells in peripheral blood of B-NHL patients may be related to immunosuppression and tumor progression.

[Survivin expression in midline T-cell lymphoma in relation to Epstin-Barr virus infection].

To investigate the expression of survivin gene and its relationship with Epstin-Barr virus (EBV) infection in midline T-cell lymphoma (MTL), immunohistochemistry staining method was used to examine the expression of survivin and EBV-latent membrane protein (LMP-1) in the 41 cases. In situ hybridization (ISH) was used to detect EBV-encoded RNA (EBER1/2). The results showed that the expression of survivin was positive in 26 cases of midline T-cell lymphoma, but no positive was detected in 10 cases of reactive lymphoid tissues. The positive expression ratio of survivin was 12.5% in cases of MTL with low grade of malignancy, and was 75.76% in cases of MTL with middle and high grades of malignancy, the significant difference was found between these two groups (chi(2) = 8.55, P < 0.01). Positive expression ratios of EBER1/2 and LMP-1 were 70.73% and 41.46% respectively. Survivin expression was not significantly different between EBER1/2 positive and negative cases (P > 0.05). It is concluded that survivin expression is up-regulated in MTL, and survivin positive expression rate is associated with the degree of malignancy. Survivin may play a role in the pathogenesis of the MTL by influencing cell apoptosis. EBV infection is not significantly associated with survivin expression in the MTL.

[Correlation of immunophenotype to cytogenetics and clinical features of adult acute myeloid leukemia].

BACKGROUND & OBJECTIVE: New WHO classification has been rapidly used in diagnosis of leukemia. Based on coexpression and correlation of lineage-associated antigens, multiparameter high-resolution flow cytometry has been developed to precisely identify lineage characteristics of leukemia. Some immunophenotypes correlate with cytogenetic abnormality and prognosis. This study was to analyze immunophenotype of naive acute myeloid leukemia (AML), and explore its correlations to cytogenetics, clinical features, and FAB subtype of AML. METHODS: Multiparameter high-resolution flow cytometry with a panel of 25 different monoclonal antibodies was used to analyze the surface and cytoplasmic antigens expressions of 96 adults with AML; G-binding technique was used to analyze karyotype of 73 of the 96 patients. RESULTS: In these AML patients, some antigens were correlated with FAB subtypes:expression of CD2 was enhanced in AML-M3; HLA-DR, CD34, and CD56 were absent in AML-M3; expression of CD19 was increased in AML-M2; expressions of CD14 and CD56 were enhanced in AML-M5; MPO was absent in AML-M0. Karyotype abnormality was detected in 40(54.8%) patients. CD22, CD56, and TdT expressions were correlated with karyotype abnormality. t(8; 21) was only detected in 10 AML-M2 patients with high expressions of CD15, CD19, CD34, and CD56; no lymphoid lineage antigens were detected in 7 AML-M3 patients with t (15; 17). Expressions of CD4 and TdT were positively correlated with patient's age; expressions of CD7 and CD14 were positively correlated with high white blood cell count; expressions of CD4, CD14, and CD56 were positively correlated with high platelet count. CONCLUSIONS: The abnormal antigen expression of AML is tightly linked with karyotype abnormality. Detection of immunophenotype may help to diagnose and classify AML.

[Immunophenotypes in 115 patients with acute myeloid leukemia by multi-color flow cytometry].

Immunophenotyping has become common in the diagnosis and classification of leukemia. To evaluate the immunophenotype of acute myeloid leukemia (AML), multiparameter flow cytometry and CD45/SSC gating were used to analyze the surface and cytoplasmic antigen expressions in 115 cases of AML. The results were compared with the French-American-British (FAB) Cooperative Group classification to help define the best use and role of multiparameter flow cytometry in the diagnosis and proper classification of AML. The results showed that CD38, CD38 and CD13 were the most commonly expressed antigen (94.8%, 91.3% and 89.6%, respectively). CD7 was the most commonly expressed lymphoid antigen (20.2%), followed by CD19 (16.5%) and CD2 (15%). Some immunophenotypes correlated with FAB type, including increased frequency of CD2 in M(3); lack of HLA-DR, CD34 and CD56 expression in M(3); increased frequency of CD19 in M(2), CD14 and CD56 in M(5) and lack of MPO in M(0). In conclusion, multiparameter flow cytometry is a reliable technique in the diagnosis of AML, and some immunophenotypes correlate with FAB type.

[Regulation of tissue factor expression in brain microvascular endothelial cells by PLA nanoparticles coating NF-kappaB decoy oligonucleotides].

OBJECTIVE: To investigate a new strategy of polylactic acid (PLA) nanoparticles delivery system coating nuclear factor-kappaB (NF-kappaB) decoy oligonucleotides (ODNs) for inhibiting TF expression in cultured brain microvascular endothelial cells(BMECs). METHODS: PLA nanoparticles coating FITC-labeled NF-kappaB decoy ODNs were formulated by nano-deposition method and the characteristics of nanoparticles were detected. BMECs were isolated and cultured in vitro. The cellular uptake and intracellular localization of nanoparticles in BMECs was detected by flow cytometry and confocal microscopy. Changes in the expressions of TF and nuclear protein P65 were examined by RT-PCR and Western blot in NF-kappaB decoy ODNs transfected BMECs by LPS stimulation. RESULTS: The decoy-nanoparticles obtained were uniform spherical particles with an effective diameter of 162.1 nm and a polydispersity index of 0.118. NF-kappaB decoy ODNs encapsulated in nanoparticles could be released in a controlled manner in phosphate-buffered saline for up to 28 days. It was observed that the cellular uptake of nanoparticles were increased with the time of incubation and the concentration of nanoparticles in the medium. Nanoparticles localized mainly in the BMECs cytoplasm. LPS-induced upregulation of TF transcription was inhibited by NF-kappaB decoy ODNs transfection but not by missense ODNs transfection. Furthermore, changes in the transcription level of TF were paralleled by a reduction of capacity of P65 in nuclear extract of NF-kappaB decoy ODNs transfected cells. CONCLUSIONS: These findings offer a potential therapeutic strategy in the control of TF expression in BMECs in vitro.

[In vitro infection of human megakaryocyte precursors by human cytomegalovirus (HCMV) and the antiviral effect of HCMV antisense oligonucleotides].

OBJECTIVE: To explore the suppression effect of human cytomegalovirus (HCMV) on megakaryocytes and their precursors and study the antiviral effect of antisense phosphorothioate deoxyoligonucleotide (ASON) against HCMV. METHODS: CD34(+) cells were induced to proliferate and differentiate committedly to megakaryocytes in a semi-solid CFU-MK culture system. Cultured cells and ASON pretreated CD34(+) cells were infected by HCMV of AD169 strain. HCMV immediate early protein (IEP) DNA and mRNA and UL36 mRNA were detected by PCR and reverse transcription-polymerase chain reaction (RT-PCR). Cytotoxicity was evaluated by MTT assay. RESULTS: HCMV AD169 suppressed the proliferation of megakaryocytes significantly. Compared with the mock group, the CFU-MK yields were decreased by 21.6%, 33.8%, and 46.3%, respectively, in 3 different titers of virus infected groups (P < 0.05). The suppression was virus titer dependent. HCMV IEP DNA, HCMV IEP mRNA and UL36 mRNA were detected in the colony cells of viral infection group. Compared with the infected group by HCMV AD169, UL36Anti treatment at 0.08 micromol/L could recover the CFU-MK yields significantly (P < 0.05). In the infected MK, which was pretreated with UL36Anti at 0.08 micromol/L, HCMV UL36 mRNA was undetectable by RT-PCR. The oligonucleotide MM(1) containing a G-to-C substitution in UL36Anti was inactive at 0.08 micromol/L but active at 0.40 micromol/L. The concentration of UL36Anti necessary to significantly affect cell growth was 90.00 micromol/L. CONCLUSIONS: HCMV AD169 infection inhibits the proliferation and differentiation of megakaryocytes and their precursors. There are early transcriptions of HCMV IE and UL36 protein in infected CFU-MK. The specific ASON has a definite anti-HCMV activity.