中国实验血液学杂志最新文献

Objective: To explore the clinical application value of metagenomic next-generation sequencing (mNGS) in pathogen detection of bloodstream infection secondary to hematologic diseases in children.

Methods: 42 children with bloodstream infections secondary to hematologic diseases admitted to the Children's Hematology and Tumor Center of the Affiliated Hospital of Guangdong Medical University from November 2021 to May 2023 were included in the study, and their clinical data, results of peripheral blood mNGS and traditional blood culture, pathogen distribution characteristics, and diagnostic efficacy of mNGS were retrospectively analyzed.

Results: Among the 42 children included, there were 2 cases (4.8%) of aplastic anemia (AA), 27 cases (64.3%) of acute lymphoblastic leukemia (ALL), 7 cases (16.7%) of acute myeloid leukemia (AML), 1 case (2.4%) of chronic myeloid leukemia (CML), 2 cases (4.8%) of hemophagocytic lymphohistiocytosis (HLH), 2 cases (4.8%) of non-Hodgkin lymphoma (NHL), and 1 case (2.4%) of Wiskott-Aldrich syndrome (WAS). In mNGS testing, pathogens were detected in 31 peripheral blood samples, with a positive rate of 73.8% (31/42), significantly higher than the pathogen positive rate of 16.7% (7/42) detected by traditional blood culture, and the difference was statistically significant (P < 0.05). Among the pathogen-positive cases detected by mNGS, 23 cases (74.2%) were positive for bacteria, 12 cases (38.7%) were positive for viruses, and 9 cases (29.0%) were positive for fungi. 32.2% (10/31) of the pathogen-positive samples detected by mNGS were mixed pathogens, which could not be effectively detected by traditional blood culture.

Conclusion: Peripheral blood mNGS has advantages in the detection of pathogens of bloodstream infection secondary to hematologic diseases, with a higher detection rate of pathogen positivity than traditional blood cultures. It can detect viruses, rare pathogens and mixed pathogens, and has good clinical application value.

Objective: To explore the construction method of a resistant multiple myeloma (MM) patient-derived xenotransplantation (PDX) model.

Methods: 1.0×10⁷ MM patient-derived mononuclear cells (MNCs), 2.0×10⁶ MM.1S cells and 2.0×10⁶ NCI-H929 cells were respectively subcutaneously inoculated into NOD.CB17-Prkdc^scid Il2rg^tm1/Bcgen (B-NDG) mice with a volume of 100 μl per mouse to establish mouse model. The morphologic, phenotypic, proliferative and genetic characteristics of PDX tumor were studied by hematoxylin-eosin staining, immunohistochemical staining (IHC), cell cycle analysis, flow cytometry and fluorescence in situ hybridization (FISH). The sensitivity of PDX tumor to bortezomib and anlotinib monotherapy or in combination was investigated through cell proliferation, apoptosis and in vitro and in vivo experiments. The effects of anlotinib therapy on tumor blood vessel and cell apoptosis were analyzed by IHC, TUNEL staining and confocal fluorescence microscope.

Results: MM PDX model was successfully established by subcutaneously inoculating primary MNCs. The morphologic features of tumor cells from MM PDX model were similar to those of mature plasma cells. MM PDX tumor cells positively expressed CD138 and CD38, which presented 1q21 amplification, deletion of Rb1 and IgH rearrangement, and had a lower proliferative activity than MM cell lines. in vitro, PDX, MM.1S and NCI-H929 cells were treated by bortezomib and anlotinib for 24 hours, respectively. Cell viability assay showed that the IC₅₀ value of bortezomib were 5 716.486, 1.025 and 2.775 nmol/L, and IC₅₀ value of anlotinib were 5 5107.337, 0.706 and 5.13 μmol/L, respectively. Anlotinib treatment increased the apoptosis of MM.1S cells (P < 0.01), but did not affect PDX tumor cells (P >0.05). in vivo, there was no significant difference in PDX tumor growth between bortezomib monotherapy group and control group (P >0.05), while both anlotinib monotherapy and anlotinib combined with bortezomib effectively inhibited PDX tumor growth (both P < 0.05). The vascular perfusion and vascular density of PDX tumor were decreased in anlotinib treatment group (both P < 0.01). The apoptotic cells in anlotinib treatment group were increased compared with those in control group (P < 0.05).

Conclusion: Bortezomib-resistant MM PDX model can be successfully established by subcutaneous inoculation of MNCs from MM patients in B-NDG mice. This PDX model, which retains the basic biological characteristics of MM cells, can be used to study the novel therapies.

Objective: To analyze the clinical characteristics and outcomes of multiple myeloma (MM) patients infected with Listeria monocytogenes (LM) in novel agent era, so as to improve clinicians' understanding.

Methods: Clinical data of 4 MM patients infected with LM in Beijing Chao-yang Hospital from October 2018 to October 2022 was analyzed retrospectively.

Results: The average age of the 4 patients was (57.5±4.1) years old. All the patients did not reach deep remission from induction therapy or experienced multiple recurrences of MM, with significant decreased immunoglobulin levels and lymphocyte counts. The initial clinical manifestation was all fever. Three patients developed nervous system symptoms 2-3 days after onset and cerebrospinal fluid examination indicated meningitis. The sensitive anti-infection agents were given according to pathogenic test results 4-5 days after onset. After treatment, two patients recovered, one patient gave up treatment and died after discharged from hospital, and one critical patient died despite exposure to sensitive antibiotics.

Conclusion: MM patients, with the application of novel agents, may have increased risk of LM infection, even critical cases. LM prevention and prompt therapy in early stage for suspected patients is key to reducing the risk of severe infection and mortality.

Diffuse alveolar hemorrhage (DAH) is a severe complication that can occur post- hematopoietic stem cell transplantation (HSCT). So far, the precise pathogenesis and risk factors of DAH post-HSCT remain elusive, diagnostic criteria have not reached a consensus, and the efficacy of existing therapeutic measures is far from satisfactory. At present, it is believed that the core mechanism of DAH post-HSCT is a vicious cycle initiated by endothelial injury, accompanied by a series of subsequent inflammatory and cellular responses. Treatment primarily focuses on managing inflammation, promoting hemostasis, and improving oxygenation. This paper reviews recent advances in understanding the pathogenesis, risk factors, clinical manifestations, diagnosis, and treatment of DAH following HSCT.

Objective: To analyze the occurrence of arterial events and platelet parameters in patients with polycythemia vera (PV) and essential thrombocythemia (ET), and to explore the characteristics of platelet parameters in patients with PV and ET and their relationship with arterial complications.

Methods: The clinical and laboratory data of newly diagnosed PV and ET patients who visited the Department of Hematology, Beijing Anzhen Hospital, Capital Medical University from August 2017 to August 2022 were retrospectively analyzed.

Results: 86 MPN patients (46 males and 40 females) were enrolled, including 44 PV patients and 42 ET patients, with an median age of 61(23-83) years. The mutation rate of JAK2V617F gene, the number of megakaryocytes in bone marrow, the incidence of splenomegaly, and the levels of white blood cell count (WBC), hemoglobin (HGB), hematocrit (HCT), platelet distribution width (PDW), mean platelet volume (MPV), platelet-large cell ratio (P-LCR) in PV patients were significantly higher than those in ET patients (P < 0.05), while the levels of PLT and PCT were significantly lower than those in ET patients (P < 0.01). 22 cases (50%) of PV patients were complicated with arterial events, of which 12 had arterial stenosis in≥2 locations. Among arterial events, the PDW of PV patients with ischemic stroke was greater than that of PV patients without ischemic stroke (P =0.003), and the PDW of PV patients with arterial stenosis in≥2 locations was greater than that of PV patients with arterial stenosis in≤1 location (P =0.037). 23 cases (54.8%) of ET patients were complicated with arterial events, and 7 cases had arterial stenosis in≥2 locations. In arterial events, the PCT of ET patients complicated with ischemic stroke was greater than that of ET patients without ischemic stroke (P =0.037), and the PCT of ET patients with≥2 locations of arterial stenosis was greater than that of ET patients with≤1 location of arterial stenosis (P =0.049). The binary logistic regression analysis showed that elevated PDW and PCT were risk factors for ischemic stroke in PV and ET patients, respectively (P < 0.05).

Conclusion: The platelet parameters of PV and ET patients exhibit significantly different characteristics. Elevated PDW and PCT can predict a higher risk of ischemic stroke in PV and ET patients, respectively.

Objective: To explore whether Ph⁺ acute lymphoblastic leukemia (ALL) cell line SUP-B15 treated with imatinib occurs a tolerant status charactered by cell proliferation suppression but apoptotic resistance, then evaluate whether IGF1-R inhibitor AEW541 can break this tolerance, and further explain its mechanisms.

Methods: SUP-B15 cells were treated with different concentrations of imatinib or AEW541. Cell proliferation was assayed by Deep Blue, and apoptotic cells were determined by Annexin V/7-AAD staining. Apoptotic rate was measured by flow cytometry after co-treatment of imatinib and AEW541. Western blot was used to evaluate ABL downstream signals, including the phosphorylation of STAT5, ERK1/2, and AKT, as well as to detect cleaved caspase-3 and PARP1, the molecular signatures of apoptosis. Furthermore, an inhibitor of STAT5 or MEK-ERK1/2 was used to confirm the key mechanism of the combination of imatinib and AEW541 induced SUP-B15 cell apoptosis.

Results: Imatinib monotherapy effectively suppressed the proliferation of SUP-B15 cells, but did not induce significant increase of apoptotic rate, leading to occurrence of tolerant status. AEW541 monotherapy did not dramatically affect the proliferation and apoptosis of SUP-B15 cells, but significantly increased apoptotic rate of SUP-B15 cells and cleavage of caspase-3 and PARP1 when combined with imatinib simultaneously. A combination of imatinib and AEW541 reduced STAT5 and ERK1/2 phosphorylation as compared with imatinib monotherapy in SUP-B15 cells, but had no impact on AKT phosphorylation.Apoptosis could be induced by STAT5 inhibitor AC-4-130, but not by MEK-ERK1/2 inhibitor trametinib in SUP-B15 cells.

Conclusion: SUP-B15 cells treated with imatinib can establish drug tolerance. IGF1-R inhibitor AEW541 can further reduce STAT5 activation, thereby boosting the effect of apoptotic induction of imatinib on SUP-B15 cells. This research may provide a new idear to overcome imatinib tolerance.

Acute myeloid leukemia (AML) is the most common and highly heterogeneous acute leukemia in adults. Despite the continuous optimization of prognostic risk stratification and treatment regimens, the overall long-term survival rate of AML patients remains low. The emergence of single cell sequencing (SCS) technology has overcome the defects of traditional sequencing to a certain extent, and realized the transformation of the research of malignant tumors from cell population level to single cell level. Consequently, it has been widely applied in many biological fields. This review mainly focuses on the application of SCS technology in the analysis of tumor heterogeneity, disease evolution, changes in tumor microenvironment, elucidation of drug resistance mechanisms and search for potential therapeutic targets in AML.

Objective: To investigate the effects of Curcumol on the malignant biological characteristics of acute myeloid leukemia (AML) cells and its molecular mechanism, and to provide theoretical and experimental evidence for the anti-leukemia treatment of traditional Chinese medicine.

Methods: After the AML cell lines HL-60 and KG-1 cells were treated different concentrations of with Curcumol. The proliferation activity of cells was detected by CCK-8 method, and the expression changes of apoptotic proteins and PI3K/AKT signaling pathway proteins were detected by Western blot. Real-time quantitative fluorescence polymerase chain reaction (RT-qPCR) was used to detect the expression of Caspase family mRNA.

Results: Curcumol could inhibit the proliferation and induce apoptosis of HL-60 and KG-1 cells, promote apoptosis by up-regulating the expression of Bax and down-regulating the expression of Bcl-2 protein (P <0.05). When Curcumol interferes with HL-60 and KG-1 cells, it can also induce programmed cell death of AML by inhibiting PI3K/AKT signaling pathway. In addition, after the intervention of Curcumol, the expression of Caspase 3, Caspase 6, Caspase 8 and Caspase 9 were up-regulated in HL-60 cells (P <0.05), the expression of Caspase 3, Caspase 8 and Caspase 9 were significantly up-regulated in KG- cells (P <0.01), while the expression of Caspase 6 was weakly affected (P <0.05), but low concentration of Curcumol (< 60 μg/ml) had no effect on the expression of Caspase 6 in KG-1 cells (P >0.05).

Conclusion: Curcumol may mediate the programmed death of AML cells by inhibiting the PI3K/AKT signaling pathway, affecting the expression of Bcl-2 family proteins, and promoting the activation of core members of Caspase family, so as to play an anti-leukemia role.