Association between cystatin C gene polymorphism and the prevalence of white matter lesion in elderly healthy subjects.

Cystatin C (CST3) is a cysteine protease inhibitor abundant in the central nervous system, and demonstrated to have roles in several pathophysiological processes including vascular remodeling and inflammation. Previously, we showed a relation of CST3 gene polymorphisms with deep and subcortical white matter hyperintensity (DSWMH) in a small case-control study. In this study, we aimed to investigate the relation in a larger cross-sectional study. Participants of a brain health examination program were recruited (n = 1795) in the study, who underwent routine blood tests and cognitive function tests. Cerebral white matter changes were analyzed by MRI. Additionally, 7 single nucleotide polymorphisms (SNPs) (-82G/C, -78T/G, -5G/A, +4A/C, +87C/T, +148G/A and +213G/A) in the promoter and coding regions of CST3 gene were examined. Among them, carriers of the minor allele haplotype -82C/+4C/+148A were significantly associated with decreased CST3 concentration in the plasma. Unadjusted analysis did not show significant relation between carriers of the minor allele haplotype and periventricular hyperintensity (PVH), but DSWMH was marginally (p < 0.054) increased in this group. After adjusting the effects of other variables like age and kidney function, logistic regression analysis revealed that carriers of the minor allele haplotype were at a significantly increased risk of developing both PVH and DSWMH. Thus, our results suggest that carriers of the minor allele haplotype -82C/+4C/+148A of CST3 gene could be at an increased risk to develop cerebral white matter disturbance.

Transplantation of a bone marrow mesenchymal stem cell line increases neuronal progenitor cell migration in a cerebral ischemia animal model.

Mesenchymal stem cell (MSC) transplantation is demonstrated to improve functional and pathological recovery in cerebral ischemia. To understand the underlying mechanism, we transplanted a MSC line (B10) in a rat middle cerebral artery occlusion (MCAO) model and checked the proliferation and migration of neuronal progenitor cells (NPCs). B10 transplantation increased NPCs in the subventricular zone and their migration towards the lesion area at an earlier time. Fourteen days after MCAO, some NPCs were differentiated to neurons and astrocytes. Although B10 transplantation increased total number of both astrocytes and neurons, it only increased the differentiation of NPC to astrocyte. The mRNA of polysialylation enzyme ST8SiaIV and a chemokine SDF-1 were persistently increased in B10-transplanted groups. SDF-1-positive cell number was increased in the core and penumbra area, which was expressed in macrophage/microglia and transplanted B10 cells at 3 days after MCAO. Furthermore, SDF-1 mRNA expression in cell culture was high in B10 compared to a microglia (HMO) or a neuronal (A1) cell line. B10 culture supernatant increased in vitro A1 cell migration, which was significantly inhibited by siRNA-mediated SDF-1 silencing in B10. Thus, our results suggested that MSC transplantation increased endogenous NPC migration in cerebral ischemic condition by increasing chemokine and polysialylation enzyme expression, which could be helpful for the restorative management of cerebral ischemia.

Single nucleotide polymorphisms of the DGKB and VCAM1 genes are associated with granulocyte colony stimulating factor-mediated peripheral blood stem cell mobilization.

We previously reported the association between LDL cholesterol level (LDL-C) and granulocyte colony stimulating factor (G-CSF)-mobilized peripheral blood (PB) hematopoietic stem cells (HSC). In this study, we investigated the association between gene single nucleotide polymorphisms (SNPs) involved in hematopoiesis and lipid level and PBHSC mobilization. In 46 patients who underwent peripheral blood stem cell harvest (PBSCH), we measured CD34-positive cells in PB and PBSCH, and the patients were classified into good, intermediate, or poor mobilizer groups based on the CD34-positive cell counts. And SNPs of the OR4C12, ENO1, RERE, DGKB, DSC3, VCAM1, CD44, and FADS1 genes were investigated. The frequency of the TT type of the DGKB gene was higher in the poor mobilizer group compared to other groups (p<0.05), whereas that of the CC type of the VCAM1 gene was high in the good mobilizer group (p<0.05). Association with the efficiency of HSC mobilization to PB were found in the SNPs of the DGKB gene involved in cell transport and SDF-1-induced migration ability and of the VCAM1 gene which is essential for HSC homing, suggesting that SNPs involved in cell migration ability might be partly involved in HSC mobilization to PB.

Low-density lipoprotein as a biomarker for the mobilization of hematopoietic stem cells in peripheral blood.

The predictor of hematopoietic stem cells (HSCs) mobilized in peripheral blood (PB) remains unknown. We retrospectively examined the relationship between serum cholesterol level and CD34-positive cells mobilized with granulocyte stimulating factor in PB. PB- mobilized CD34-positive cells were significantly higher in patients with high titers of total cholesterol and low-density lipoprotein cholesterol (LDL-C) than in patients with normal levels (average total cholesterol, 122.94 vs. 51.03/µL, p<0.05; average LDL-C 130.07 vs. 53.77, p<0.05). Multivariable analysis showed that LDL-C significantly influenced PB-mobilized CD34-positive cells, suggesting that LDL-C may be an effective biomarker for mobilization of HSCs in PB.

Therapy-related Ph+ leukemia after both bone marrow and mesenchymal stem cell transplantation for hypophosphatasia.

Bone marrow (BM) transplantation (BMT) is one of the treatment strategies for congenital metabolic disease, but leukemia secondary to intensive cytoreductive treatment is a major concern. Besides BM cells, mesenchymal stem cells (MSC) are also used for transplantation. An 8-month-old girl with hypophosphatasia underwent transplantation of haploidentical BM cells followed by two transplants of MSC obtained from her father to facilitate osteogenesis. Fludarabine(Flu)/cyclophosphamide (CPA)/anti-thymocyte globulin were used for myeloablative conditioning, but the patient developed therapy-related leukemia harboring t(9;22)(q34;q11.2); minor BCR-ABL (t-leukemia with Ph) at the age of 32 months. At the age of 40 months she underwent a second BM and third MSC transplant from the same donor. Thereafter, she achieved complete histological and molecular remission. The present case suggests that the combination of cytotoxic agents (Flu/CPA) and MSC led to t-leukemia with Ph as a consequence of chromosome instability and suppression of host anti-tumor immunity.

[Relativity in multiple myeloma and KL-6].

KL-6 is a high-molecular-weight mucinous glycoprotein discovered as a pulmonary adenocaricinoma related antigen. Its levels are used as a biomarker of lung injury in interstitial pneumonia. We here report a case of multiple myeloma with Bence-Jones lambda type whose serum KL-6 level was revealed high at a concentration of 19,400 U/ml. Next, we analyzed the blood test profiles and the concentrations of KL-6 in 20 patients with multiple myeloma. CD19/CD56 double negative fraction on myeloma cells with high expression of CD38 was found in all 5 patients with multiple myeloma having elevated KL-6 level. Patients with interstitial pneumonia show high level of KL-6. We, therefore, need to differentiate the interstitial pneumonia and the above-mentioned multiple myeloma when serum KL-6 level is high.

Cyclopamine induces eosinophilic differentiation and upregulates CD44 expression in myeloid leukemia cells.

Cyclopamine, a plant-derived steroidal alkaloid, inhibits the hedgehog (Hh) signaling pathway by antagonizing Smoothened. This drug can induce the differentiation of myeloid leukemia cell lines and acute myeloid leukemia (AML) cells in primary culture. The treated cells were stained with Luxol-fast-blue, which is specific for eosinophilic granules. Ligation of CD44 with some specific monoclonal antibodies can reverse the differentiation of AML cells. Combined treatment with cyclopamine and a monoclonal antibody to ligate CD44 more than additively induced the differentiation of HL-60 cells. These results may provide useful information for the development of a CD44-targeted therapy in AML.

Effective ex vivo expansion of hematopoietic stem cells using osteoblast-differentiated mesenchymal stem cells is CXCL12 dependent.

Effective ex vivo expansion of hematopoietic stem cells (HSCs) is a prerequisite for HSC transplantation. Growth and maintenance of HSC is dependent on cytokine and niche factors. We investigated whether mesenchymal stem cells (MSCs) or osteogenic cytokine-differentiated MSCs play a role in HSC expansion. We used the human HM3.B10 (B10) MSC cell line and the osteoblast-differentiated B10 (Ost-B10) as a feeder layer and examined ex vivo expansion of CD34(+)CD38(-) HSCs obtained from peripheral blood (PB) and cord blood (CB) with or without several growth cytokines. Both undifferentiated B10 and Ost-B10 cells exhibited similar effects on total HSC expansion; however, Ost-B10 demonstrated a higher potency in CD34(+)CD38(-) cell-specific proliferation in the presence of cytokines compared to undifferentiated B10 HSCs. Colony-forming cell assay and long-term culture initiating cell assay revealed that Ost-B10 displayed multipotent differentiation and enabled long-term ex vivo culture of HSCs. We next examined the relationship between HSC expansion and the presence of various chemokines. CXCL4 and CXCL12 expression were increased in Ost-B10 cells compared with the B10 cells. CD34(+)CD38(-) cells were significantly increased with CXCL12, but not CXCL4 treatment. siRNA inhibition of CXCL12 decreased CXCL12 secretion in both B10 and Ost-B10, whereas expansion of CD34(+)CD38(-) cells was decreased in Ost-B10 alone. These results demonstrated that ex vivo expansion of HSCs may be highly effective through osteoblast-differentiated MSCs acting as a feeder layer, and likely operates through the CXCL12 chemokines signaling pathway.

Pure red cell precursor toxicity by linezolid in a pediatric case.

Linezolid (LZD)-induced myelosuppression has been reported in adults; however, LZD-induced pure red cell precursor toxicity rarely occurs. A 2-year-old boy diagnosed with infective endocarditis by Streptococcus mitis received LZD after developing resistance to multiple antibiotics. Although his infective symptoms were improved by LZD, progressive anemia was noticed 2 weeks after LZD therapy. Four weeks after LZD administration, his hemoglobin level was 6.5 g/dL and reticulocytes less than 0.1%. Bone marrow examination revealed markedly decreased erythropoiesis with cytoplasmic vacuolation of erythroblasts. Anemia recovered 19 days after cessation of LZD. Elevated protoporphyrin and a high LZD level in the blood suggested that mitochondrial disturbance by high-dose and long-term treatment with LZD may have been responsible for LZD-induced pure red cell precursor toxicity.