Chest CT pulmonary angiography (CTPA) has certain auxiliary diagnostic value for the clinical diagnosis of invasive pulmonary aspergillosis (IPA) . Three patients with hematological malignancies were reported, including 2 ones after allogeneic hematopoietic stem cell transplantation and 1 ones after chemotherapy for refractory recurrent leukemia. Each patient was treated with antibiotics for at least 48 hours after the onset of fever, they all underwent chest high-resolution CT (HRCT) scans without fever resolution. CT revealed at least one dense pulmonary consolidation shadow with a diameter greater than 10 mm, and subsequently a CTPA examination was performed to observe the effect of CTPA imaging signs for the diagnosis of IPA. There were 2 patients with positive vascular occlusion sign (VOS) and 1 patient with negative VOS detected by CTPA. Among them, 2 patients with positive VOS were diagnosed with possible IPA and received with diagnosis-driven antifungal treatment, which improved their conditions. One patient with negative VOS sign was diagnosed with diffuse large B-cell lymphoma involving the lungs. After receiving anti-lymphoma treatment, the lesions significantly reduced in size. The vascular occlusion sign detected by CTPA is relatively characteristic. For high-risk IPA patients, it helps to improve the specificity of imaging diagnosis and guide clinical treatment decisions.

Chest CT pulmonary angiography (CTPA) has certain auxiliary diagnostic value for the clinical diagnosis of invasive pulmonary aspergillosis (IPA) . Three patients with hematological malignancies were reported, including 2 ones after allogeneic hematopoietic stem cell transplantation and 1 ones after chemotherapy for refractory recurrent leukemia. Each patient was treated with antibiotics for at least 48 hours after the onset of fever, they all underwent chest high-resolution CT (HRCT) scans without fever resolution. CT revealed at least one dense pulmonary consolidation shadow with a diameter greater than 10 mm, and subsequently a CTPA examination was performed to observe the effect of CTPA imaging signs for the diagnosis of IPA. There were 2 patients with positive vascular occlusion sign (VOS) and 1 patient with negative VOS detected by CTPA. Among them, 2 patients with positive VOS were diagnosed with possible IPA and received with diagnosis-driven antifungal treatment, which improved their conditions. One patient with negative VOS sign was diagnosed with diffuse large B-cell lymphoma involving the lungs. After receiving anti-lymphoma treatment, the lesions significantly reduced in size. The vascular occlusion sign detected by CTPA is relatively characteristic. For high-risk IPA patients, it helps to improve the specificity of imaging diagnosis and guide clinical treatment decisions.

Objective: To evaluate the effects of endothelial cell-targeted soluble Notch ligand hD1R protein on the proliferation of acute myeloid leukemia (AML) cells. Methods: The expression levels of Notch1, Notch2, Notch3, Notch4, Hes1 in bone marrow CD34⁺ cells from 24 cases of untreated AML (AML group) and 9 healthy controls (control group) were determined by real time quantitative polymerase chain reaction (PCR) . Recombinant hD1R protein was first induced and purified. Bone marrow CD34⁺ cells were co-cultured on human umbilical vein endothelial cells (HUVEC) supplemented with a cocktail containing 5 types of human cytokines (5GF) and soluble hD1R. The cultured cells were tested under different culture conditions including PBS group (PBS replaces HUVEC) , hD1R group, 5GF group, GSI group (hD1R plus GSI) . Proliferation and apoptosis of cultured cells were also analyzed. Real time quantitative PCR was used to test the expression levels of Hes1 and Bcl-2 in cultured cells. Results: The expression levels of Notch1 and Hes1 in primary AML patients were significantly lower, and Notch4 expression was higher compared to the control group (P<0.05) . Cell counting showed a remarkable decrease of AML cells number in the culture with hD1R compared with that in the PBS group[ (0.74±0.13) ×10⁵ vs (2.16±0.21) ×10⁵, P<0.01]. FACS analysis showed that the percentage of AML cells was (18.48±2.51) % in apoptosis, which was higher than that of control cells (3.19±0.58) % after co-culture with hD1R. AML cells in the hD1R group underwent significantly increased apoptosis compared with those in the PBS one (P<0.05) . Moreover, apoptosis of AML cells in the GSI group was lower than that in the hD1R one (P<0.05) . Apoptosis in the PBS group also decreased compared with that in the 5GF one (P<0.05) . Finally, hD1R up-regulated Hes1 expression and inhibited Bcl-2 one in the AML cells. Conclusion hD1R effectively activated Notch signaling and down-regulated Bcl-2 mRNA in AML cells, which lead to cell apoptosis.

OBJECTIVETo evaluate the effects of endothelial cell- targeted soluble Notch ligand hD1R protein on expansion and engraftment of cord blood hematopoietic stem/progenitor cell (CB HSPCs).

METHODSRecombinant hD1R protein was first induced and purified. Human cord blood CD34⁺ cells were co-cultured on human umbilical vein endothelial cells (HUVECs) supplemented with a cocktail containing 5 types of human cytokines including TPO, SCF, FL, IL-6, IL-3 (5GF) and soluble hD1R. The expansion of CD34⁺ cells was tested under different culture conditions including PBS group (PBS replaces HUVEC), hD1R group, sup group (HUVEC supernatant replaces HUVEC), fix group (fixed HUVEC replaces HUVEC), Day 0 group (Control). Cell cycle and apoptosis of cultured cells were also analyzed. Their progeny expanded in PBS or hD1R group were transplanted into sublethally irradiated NOD/SCID mice. The percentages of human CD45⁺ (hCD45⁺) cells in the marrow of recipient mice were determined by FACS 12 weeks later.

RESULTShD1R induced more expansion in the total number of CD34⁺ cells cocultured with HUVECs plus 5GF, which was 87.50-fold increase compared to the Day 0 group, and 7.98-fold increase than that of PBS group. FACS analysis also showed that the percentage of CD34⁺ cells was 77.0% in G0/G1 phase in the hD1R group, which indicated that hD1R enhanced HSPCs expansion and inhibited apoptosis. Moreover, hD1R significantly promoted human HSPC engraftment after BM transplantation in irradiated mice.

CONCLUSIONThe Notch-mediated ex vivo expansion system has been established and hD1R promoted expansion and engraftment of human CB HSPCs, which provided the evidence for further clinical application.

Animals ; Antigens, CD34 ; Cells, Cultured ; Coculture Techniques ; Endothelial Cells ; immunology ; Fetal Blood ; Hematopoietic Stem Cells ; immunology ; Humans ; Membrane Proteins ; immunology ; Mice