Specific Activity of Electron-Beam Synthesis Immobilized Hyaluronidase on G-CSF Induced Mobilization of Bone Marrow Progenitor Cells

Comparison of the efficacy of hematopoietic stem cell mobilization regimens: a systematic review and network meta-analysis of preclinical studies

BACKGROUND

Mobilization failure may occur when the conventional hematopoietic stem cells (HSCs) mobilization agent granulocyte colony-stimulating factor (G-CSF) is used alone, new regimens were developed to improve mobilization efficacy. Multiple studies have been performed to investigate the efficacy of these regimens via animal models, but the results are inconsistent. We aim to compare the efficacy of different HSC mobilization regimens and identify new promising regimens with a network meta-analysis of preclinical studies.

METHODS

We searched Medline and Embase databases for the eligible animal studies that compared the efficacy of different HSC mobilization regimens. Primary outcome is the number of total colony-forming cells (CFCs) in per milliliter of peripheral blood (/ml PB), and the secondary outcome is the number of Lin^- Sca1⁺ Kit⁺ (LSK) cells/ml PB. Bayesian network meta-analyses were performed following the guidelines of the National Institute for Health and Care Excellence Decision Support Unit (NICE DSU) with WinBUGS version 1.4.3. G-CSF-based regimens were classified into the SD (standard dose, 200-250 μg/kg/day) group and the LD (low dose, 100-150 μg/kg/day) group based on doses, and were classified into the short-term (2-3 days) group and the long-term (4-5 days) group based on administration duration. Long-term SD G-CSF was chosen as the reference treatment. Results are presented as the mean differences (MD) with the associated 95% credibility interval (95% CrI) for each regimen.

RESULTS

We included 95 eligible studies and reviewed the efficacy of 94 mobilization agents. Then 21 studies using the poor mobilizer mice model (C57BL/6 mice) to investigate the efficacy of different mobilization regimens were included for network meta-analysis. Network meta-analyses indicated that compared with long-term SD G-CSF alone, 14 regimens including long-term SD G-CSF + Me6, long-term SD G-CSF + AMD3100 + EP80031, long-term SD G-CSF + AMD3100 + FG-4497, long-term SD G-CSF + ML141, long-term SD G-CSF + desipramine, AMD3100 + meloxicam, long-term SD G-CSF + reboxetine, AMD3100 + VPC01091, long-term SD G-CSF + FG-4497, Me6, long-term SD G-CSF + EP80031, POL5551, long-term SD G-CSF + AMD3100, AMD1300 + EP80031 and long-term LD G-CSF + meloxicam significantly increased the collections of total CFCs. G-CSF + Me6 ranked first among these regimens in consideration of the number of harvested CFCs/ml PB (MD 2168.0, 95% CrI 2062.0-2272.0). In addition, 7 regimens including long-term SD G-CSF + AMD3100, AMD3100 + EP80031, long-term SD G-CSF + EP80031, short-term SD G-CSF + AMD3100 + IL-33, long-term SD G-CSF + ML141, short-term LD G-CSF + ARL67156, and long-term LD G-CSF + meloxicam significantly increased the collections of LSK cells compared with G-CSF alone. Long-term SD G-CSF + AMD3100 ranked first among these regimens in consideration of the number of harvested LSK cells/ml PB (MD 2577.0, 95% CrI 2422.0-2733.0).

CONCLUSIONS

Considering the number of CFC and LSK cells in PB as outcomes, G-CSF plus AMD3100, Me6, EP80031, ML141, FG-4497, IL-33, ARL67156, meloxicam, desipramine, and reboxetine are all promising mobilizing regimens for future investigation.

Role of JNK and Involvement of p53 in Stimulation of Growth Potential Realization of Mesenchymal Precursor Cells by Alkaloid Songorine

The role of JNK-mediated signal pathway and participation of p53 transcription factor in stimulation of realization of the growth potential of the mesenchymal precursor cells by alkaloid songorine were examined in vitro. Specific inhibitors of JNK and p53 enhanced stimulation of fibroblast colony/cluster formation and proliferative activity of mesenchymal precursor cells. Under these conditions, more pronounced effects were observed with early precursors of fibroblast CFU and in both cases were accompanied by a decrease in differentiation index of progenitor elements.

Role of cAMP- and IKK-2-Dependent Signaling Pathways in Functional Stimulation of Mesenchymal Progenitor Cells with Alkaloid Songorine

The role of cAMP- and IKK-2-dependent pathways in stimulation of the growth capacity of mesenchymal progenitor cells with alkaloid songorine was studied in vitro. Inhibitors of adenylate cyclase and IKK-2 were shown to abolish the increase in proliferative activity of progenitor cells. Moreover, blockade of the inhibitory kinase complex was accompanied by a decrease in the intensity of progenitor cell differentiation.

Stratification of chondroitin sulfate binding sites in 3D-model of bovine testicular hyaluronidase and effective size of glycosaminoglycan coat of the modified protein

A 3D-model of bovine testicular hyaluronidase (BTH) was constructed based on established tertiary structure of human hyaluronidase Hyal1 using a molecular homological modeling method in silico. The analysis of the BTH 3D-model demonstrated lysine residue stratification during enzyme modification. The 3D-model of chondroitin sulfate (CHS)-modified hyaluronidase (BTH-CHS) was obtained by modeling covalent binding of lysine residues with benzoquinone-activated CHS. The degree of enzyme modification and the length of CHS chains were varied during 3D modeling. The importance of deep BTH modification degree for the formation of active and stable enzyme derivatives was shown, as determined earlier experimentally. The effective size of the CHS coat for productive BTH modification was confirmed. It is theoretically achieved at the increase in molecular mass of BTH-CHS derivative to approximately 140-180 kDa and can be practically obtained, according to experimental data, using CHS of different molecular mass (30-50 as well as 120-140 kDa).

Role of cAMP and IKK-2-dependent signaling in the realization of growth potential of mesenchymal progenitor cells

We studied the role of cAMP- and IKK-2-mediated pathways in the realization of growth potential of mesenchymal progenitor cells in vitro. It had been found that adenylate cyclase inhibitor 2',5'-dideoxyadenosine had no effect on the proliferation and differentiation of fibroblastic CFU. A decrease in differentiation rate of progenitor cells was observed after the treatment with specific IKK-2 blocker inhibitor-kinase complex.

Involvement of cAMP- and IKK-2-dependent signal pathways in the growth capacity of mesenchymal progenitor cells under the influence of basic fibroblast growth factor

We studied the role of cAMP- and IKK-2-dependent pathways under conditions of functional stimulation of mesenchymal progenitor cells by basic fibroblast growth factor. An adenylate cyclase inhibitor 2',5'-dideoxyadenosine had no effect on functional activity of early (primitive) mesenchymal precursors. This agent produced a stimulatory effect on proliferation of stromal precursor cells. Mitotic activity of mesenchymal progenitor cells was shown to decrease after treatment with a specific blocker of the IKK-2 kinase-inhibitor complex.