Study on the immune functions of dendritic cells regulated by histone deacetylase inhibitor Belinostat / 中华血液学杂志

Objective: To explore effects of histone deacetylase inhibitor Belinostat on the immunologic function of dendritic cells (DC) and its possible mechanism. Methods: Cultured mouse bone marrow-derived DC from C57BL/6 mouse in vitro. The experiments were divided into 0, 50, 100 nmol/L Belinostat + immature DC (imDC) group, and 0, 50, 100 nmol/L Belinostat mature DC (mDC). The changes of the ultrastructure of DC were observed by transmission electron microscope (TEM). Immunophenotype and CCR7 expression rate were detected by FCM, and the migration rate was observed by chemotaxis assay. The proliferation of lymphocytes stimulated by different DC was detected by mixed lymphocyte culture reaction. The cytokines in the culture supernatant, including TNF-α, IL-12 and IL-10, were examined by ELISA. RQ-PCR was used to examine the relative expression of mRNA in RelB. Results: Successful cultured and identified the qualified imDC and mDC. Belinostat decreased the expression of CCR7 on imDC [(25.82±7.25)% vs (50.44±5.61)% and (18.71±2.00)% vs (50.44±5.61)%], meanwhile increased the rate on mDC [(71.14±1.96)% vs (64.90±1.47)%]. Chemotaxis assay showed that the migration rate of Belinostat+imDC and Belinostat+mDC group were both decreased, but the difference in imDC was not significant. T lymphocyte proliferation rate stimulated by 100 nmol/L Belinostat+imDC group was lower than imDC group in condition irritation cell∶reaction cell=1∶2 [(227.09±13.49)% vs (309.49±53.69)%]. Belinostat significantly suppressed the secretion of cytokines TNF-α, IL-12 and IL-10 (all P<0.01). The relative expression of mRNA in RelB was slightly decreased in Belinostat+imDC and Belinostat+mDC group (all P<0.05). Conclusion: Belinostat could effectly suppress DC maturation and regulate immune tolerance of DC, which may be due to the down-regulation of mRNA level of RelB in DC.

Establishment of Mouse Model with Humanized Chronic Myeloid Leukemia / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To establish a BALB/c nude mouse model with the huamanized chronic myeloid leukemia (CML) for the study of human CML.</p><p><b>METHODS</b>The BALB/c nude mice aged 4 weeks pretreated by splenectomy, the cyclophosphamide intraperitoneal injection and sublethal irradiation (SLI) were transplanted intravenously with bone marrow mononuclear cells from CML patients. The SLI-pretreated nude mice were divided into 2 groups: group A, in which the nude mice were injected with 0.3 ml PBS; group B, in which the nude mice were infused intravenously with 4.5×10mononuclear cells from CML patients. Then the changes of body weight and appetite were observed, the hemogram and cell morphology were determined, the expressions of human CD13 and CD45 were detected by flow cytometry, the pathologic analysis of bone, liver and intestine were performed by biopsy, and the BCR/ABL fusion gene was detected by RT-PCR.</p><p><b>RESULTS</b>The mice in group B displayed weakness, auantic, less foodintake and instabiligy of gait as time want on. The average survival time was 46.2±4.2 d (45-57 d). On the third week, the CD13CD45cells accounted for 0.56±0.05% and 2.56±0.36% respectively in group A and B. While on the sixth week, the CD13CD45cells accounted for 0.44±0.07% and 4.97±0.43% in A and B groups respectively, these results showed that cell count in B group was significantly higher than that in A group(P<0.05). Pathological examination showed that the leukemic cells were found in bone marrow of group B. The BCR/ABL fusion gene could be detected in bone marrow.</p><p><b>CONCLUSION</b>BALB/c nude mouse model with huamanized chronic myeloid leukemia(CML) model has been established by pretreating mice with SLI. The survival time of mice in this model has been long, and the cost to establish the model is low.</p>