Retinoic Acid Promotes Interleukin-4 Plasmid-Dimethylsulfoxide Topical Transdermal Delivery for Treatment of Psoriasis

BACKGROUND: Psoriasis is an autoimmune disease that is caused by a shift in the Th1/Th2 balance toward Th1-dominant immunity. It has been established as an effective treatment to counteract psoriasis by subcutaneous injection of recombinant interleukin (IL)-4, and IL-4 gene therapy by topical transdermal penetration has shown its antipsoriatic effect in mice. Retinoic acid (RA) and dimethylsulfoxide can increase the efficiency of gene transfection in the topical transdermal delivery system. OBJECTIVE: We investigated whether RA could improve anti-psoriasis efficiency using IL-4 expression plasmid pORF-mIL-4 (pIL-4) via transdermal delivery system in K14-vascular endothelial growth (K14-VEGF) factor transgenic mice. METHODS: After pretreatment with RA, plasmid pIL-4 in 10% dimethylsulfoxide was applied to the ear skin by topical transdermal penetration. Hematoxylin- eosin staining and immunohistochemistry were performed with ear samples to evaluate anti-psoriasis efficiency in mice. RESULTS: The psoriasis pathological features were relieved and psoriasis-associated factors were significantly reduced. CONCLUSION: Our results reveal that topical application of pIL-4 in dimethylsulfoxide by transdermal delivery with RA pretreatment can improve psoriasis significantly.

Effects of chloroquine diphosphate on proliferation and apoptosis of human leukemic K562 cells / 中国实验血液学杂志

The purpose of this study was to investigate the effects of chloroquine diphosphate on the proliferation and apoptosis of human leukemic K562 cells, and to elucidate its possible mechanism of activity. The inhibitory effect of chloroquine diphosphate with different concentrations on K562 cell proliferation was detected by MTT method. Apoptosis was measured by flow cytometry (FCM); morphological analysis of apoptosis was performed after staining with propidium iodide (PI) under fluorescence microscope; cell apoptosis was assessed by the DNA ladder shown agarose gel electrophoresis. After treatment with chloroquine diphosphate, K562 cells were stained by Rhodamine 123 to detect changes in mitochondrial transmembrane potential (DeltaPsim) by FCM. The results showed that the cell viability decreased in dose-dependent manner, following chloroquine diphosphate treatment at different concentrations (1.5625, 3.125, 6.25, 12.5, 25, 50 and 100 micromol/L) for 24, 48 and 72 hours. By FCM analysis, the significant increases of sub-G(1) were observed. DNA ladder was detected and apoptotic nuclei were observed. DeltaPsim decreased in K562 cells after chloroquine diphosphate treatment. It is concluded that the chloroquine diphosphate can inhibit the proliferation of K562 cells and induce cell apoptosis, which may relate to down-regulation of mitochondrial transmembrane potential (DeltaPsim).

Effect of several anti-tumor drugs on apoptosis induction in Jurkat cell line / 中国实验血液学杂志

Cisplatin (CDDP), homoharringtonine (HHT), mitoxantrone (MIT) and hydroxycamptothecin (HCPT) are highly effective anti-tumor drugs. To evaluate their effects in the therapy of leukemia and establish a valuable method to estimate anti-tumor drugs, Annexin V/PI double parameter flow cytometry was used to detect the effects of these drug inducing apoptosis and death in Jurkat cell line. The results showed that MIT and HCTP-induced apoptosis effects on Jurkat cell line were obvious at 4 hours in early phase after adding drug (P < 0.05) and at 8 hours in late phase after adding drug (P < 0.05). HHT had obvious effect on inducing apoptosis of Jurkat cells, but no significant difference from low to high doses. The effect of CDDP on inducing apoptosis of Jurkat cell line was obviously weaker than that of HHT, MIT and HCPT, its weak effect on apoptosis of Jurkat cell line was found only at high concentration of drug for long time. Death effects on Jurkat cell line can not be observed in every experimental group. It is concluded that low dose of MIT can effectively induced apoptosis of Jurkat cell line. Annexin V/PI double parameter flow cytometry can be used as a reliable method for clinical screening anti-tumor drugs.

Antineoplastic effect of valproic acid and trichostatin on HL-60 and K562 cells / 中国实验血液学杂志

The objective of this study was to investigate antineoplastic effects of valproic acid (VPA) and trichostatin (TSA) on HL-60 and K562 cells in vitro, and the synergic effects of VPA or TSA in combination with ATRA. The inhibitory effects of VPA, TSA and ATRA in various concentrations and different combinations on proliferation of HL-60 and K562 cells were observed by cell growth curves, 50% inhibitory concentration (IC(50)), as well as inhibition of leukemia colony growth at different time points. The characteristics of cell differentiation or apoptosis were analyzed by cytochemical staining, differentiation antigen detection, cell cycle assay and A(NBT)/A(MMT) value determination. The results showed that HL-60 cell had a lower IC(50) of VPA and TSA compared with K562 cells. ATRA could significantly enhance the inhibition of VPA, TSA on clonegenicity of HL-60 cells and inhibition of VPA on clonegenicity of K562 cells. HL-60 cells treated with VPA displayed the phenotype of neutrophilic like cells, and showed the increases of NBT reduction rate and CD11b expression. No evidence for K562 differentiation was found. It is concluded that both VPA and TSA inhibit HL-60 cells growth in vitro. VPA induces differentiation of HL-60 cells to granulocyte. VPA and TSA have a moderate anti-proliferative effect on K562 cells. None of these agents induces K562 cell differentiation.

Analysis of T cell subsets and CD3zeta chain expression in myelodysplastic syndrome patients / 中国实验血液学杂志

Immune mediated suppression of hematopoiesis has been considered as one of the most important mechanisms leading to pancytopenia in myelodysplastic syndromes. This research was aimed at evaluating immune state of the MDS patients, analyzing the peripheral blood T cell subsets and CD3zeta chain expression and searching the possible reasons of hematopoietic disorders in 11 cases of MDS. Peripheral blood mononuclear cells were collected from 11 patients whose diagnosis was confirmed according to the new WHO diagnostic criteria. Flow cytometry was used for the counts of IFNgamma(+)CD4(+) cell (Th1), IL4(+)CD4(+) cell (Th2), IFNgamma(+)CD8(+) cell (Tc1), and IL4(+)CD8(+) cell (Tc2), and for the analysis of expression of CD3zeta chain in T cell subsets. The results showed that CD8(+) cells increased significantly in MDS patients; there was no significant difference between Th1/Th2, Tc1/Tc2 ratios of T cell subsets and normal control; CD3zeta chain, the functional protein in the signal transduction pathway of T cell, was over expressed in the CD8(+) cell. In conclusion, research indicates that abnormal changes of T cell subgroups exist in peripheral blood of MDS patients. Enhancement of CD8(+) cells and over-expression of CD3zeta chain are important features, which suggest that CD8(+) cells play the most critical role in the pathologic process as compared with other T cell subsets. The over active immunity mediated by T cell subset may be one of the major mechanisms resulting in cytopenia in MDS.

Prokaryotic expression of extracellular ligand binding domains of chick tie-2 and its anti-angiogenesis effect / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the prokaryotic expression of extracellular ligand binding domains of chick tie-2, the purification, refolding conditions of the recombinant protein, and its anti-angiogeneic effect.</p><p><b>METHODS</b>A DNA fragment encoding extracellular ligand binding domains of chick tie-2 was obtained by PCR amplification using a previous constructed plasmid as a template. The amplified fragment was then inserted into prokaryotic expression vector pQE30, and was expressed in E.Coli XL-1 blue by adding isopropyl-beta-D-thiogalactoside(IPTG). The recombinant protein in inclusion bodies was purified by nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography under denatured conditions. Then the refolding of the purified protein was performed with gradient dialysis. The target protein was injected s.c. into mouse, and the antibody was detected by ELISA and Western blot analysis. The antibody was purified from the antiserum and then incubated with human umbilical endothelial vein cell (HUEVC) to find its anti-angiogenesis in vitro by using propidium iodide(PI) dying through FACS. Alginate encapsulated tumor cell assays were performed and micro-vessel density was determined by counting per high power field in the sections stained with an antibody reactive to CD31 to test its inhibition of angiogenesis.</p><p><b>RESULTS</b>The recombinant protein was highly expressed in E.Coli XL-1 blue, and the antibody produced in mouse could specifically recognize the recombinant protein. The purified antibody could induce apoptosis of HUEVC in vitro. The anti-angiogenic effect of the antibody could also be found in alginate-encapsulate tumor cell assay and by counting micro-vessel density.</p><p><b>CONCLUSION</b>The protein of extracellular ligand binding domains of chick tie-2 can be expressed at high level in the prokaryotic expression system, and the expressed protein can induce immune response in mouse. Furthermore, the antibody can induce the anti-angiogenic effect.</p>