Establishment of human acute monocytic leukemia model with systemic infiltration in NPG mice.

A model construction of systemic acute leukemia is challenging. Herein, we established a systemic leukemia mouse model using highly immunodeficient NPG mice without any immunosuppressive treatments. NPG mice received tail intravenous injection of SHI-1 cells at the concentration of 1×107 cells (group A) or 5×107 cells (group B) and randomly sacrificed each seven days post-inoculation. Tumor development was monitored using nested-PCR, peripheral blood-smear analysis, flow cytometry, pathological examinations, and immunohistochemistry. The median survival of mice in groups A and B were 33.0 and 30.0 days, respectively. Blast cells in peripheral blood appeared on day 14 in group B, and on day 21 in group A. In addition, SHI-1 cell specific MLL-AF6 mRNA was detected in both spleen and bone marrow on day 14 post-inoculation. 21 days after inoculation, we observed human CD45+CD33+ cells with an SH-1-immunophenotype in the peripheral blood, spleen, and bone marrow, as well as solid neoplasms in multiple organs. Moreover, the histologically infiltrated leukemic cells expressed CD45. In conclusion, the current study demonstrated the normal growth of SHI-1 cells in the NPG mice without immunosuppression, which caused systemic leukemia similar to that observed in acute leukemia patients. We developed an efficient and reproducible model to study leukemia pathogenesis and progression.

Multiple myeloma with CD138 changed from positive to negative: A case report.

BACKGROUND: Multiple myeloma (MM) is a common malignant disease of the blood system, caused by the neoplastic proliferation of plasma cells that accumulate in bone marrow (BM). Here, we report a case of MM patient with CD138 marker changed from positive to negative. METHODS: BM and peripheral blood samples from a 48-year-old patient with MM were examined and analyzed by conventional morphology, flow cytometry, and immunodetection. RESULTS: Imaging examination and clinical manifestations fulfilled criteria for MM. On the first hospitalization, flow cytometry showed that the cells were CD138+ /CD38+ /CD19- /CD56+ . However, on the fifth hospitalization, flow cytometry revealed that the cells were CD138- /CD38+ /CD19- /CD56+ . CONCLUSIONS: MM is diagnosed on imaging and clinical manifestations, immunophenotype of flow cytometry is also an important method of diagnosing MM. However, the discovery of atypical immunophenotypes cannot prevent the diagnosis of MM, even provide a clue of disease progression.