Research progress of methodological techniques of generation of platelets from induced pluripotent stem cells in vitro / 中国输血杂志

Platelets play a role in hemostasis in vivo, and platelet transfusion is the main means to treat bleeding diseases caused by thrombocytopenia or platelet dysfunction. However, platelets are in short supply due to the increasing demand for platelet products in clinical, the limited number of blood donors and the disadvantages of platelet products such as short shelf life and bacteria contamination. Currently, induced pluripotent stem cells are considered an ideal source for producing platelets in vitro. They have the potential for self-renewal and differentiation into any cell type, and can be obtained and manipulated easily. Given the recent advances in megakaryocytic series, bioreactors, feeder-free cell production and large-scale propagation research, platelet preparations derived from induced pluripotent stem cells have gradually shown great potential for clinical applications. Considering the minimal risk of alloimmunization and tumorigenesis with these blood products, they are promising to become the standard source of future blood transfusions. This paper reviews the research progress of the methodological techniques of in vitro generation of platelets from induced pluripotent stem cells.

Establishment of a platelet production model by bone marrow cavity transplantation of mouse primary megakaryocytes / 中华血液学杂志

Objective: To establish an intramedullary transplantation model of primary megakaryocytes to evaluate the platelet-producing capacity of megakaryocytes and explore the underlying regulatory mechanisms. Methods: Donor megakaryocytes from GFP-transgenic mice bone marrow were enriched by magnetic beads. The platelet-producing model was established by intramedullary injection to recipient mice that underwent half-lethal dose irradiation 1 week in advance. Donor-derived megakaryocytes and platelets were detected by immunofluorescence staining and flow cytometry. Results: The proportion of megakaryocytes in the enriched sample for transplantation was 40 to 50 times higher than that in conventional bone marrow. After intramedullary transplantation, donor-derived megakaryocytes successfully implanted in the medullary cavity of the recipient and produce platelets, which showed similar expression of surface markers and morphology to recipient-derived platelets. Conclusion: We successfully established an in vivo platelet-producing model of primary megakaryocytes using magnetic-bead enrichment and intramedullary injection, which objectively reflects the platelet-producing capacity of megakaryocytes in the bone marrow.

Research Progress on the Mechanism of Tubulin in Megakaryopoiesis and Regulation of Platelet Count--Review / 中国实验血液学杂志

Tubulin affects platelets count through the control of mitosis and the formation of pro-platelets during the maturation of megakaryoblast to platelets. Tubulin is involved in maintaining the integrity of platelet skeleton, and also participates in the change of platelet morphology during platelet activation. Some new anti-tumor drugs targeting cell mitosis are trying to reduce the effect on tubulin in order to reduce the side effect of drugs on platelet formation. In some patients with thrombocytopenia, the variation and polymorphism of the tubulin gene affect the structure of microtubule multimers, which leads to the decrease of platelet formation. This review summarized the latest progresses of tubulin in the regulation of megakaryopoiesis and thrombopoiesis.

Effect of Rheb1 in the Development of Mouse Megakaryocyte-Erythroid Progenitor Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of Rheb1 in the development of mouse megakaryocyte-erythroid progenitor cells and its related mechanism.@*METHODS@#Rheb1 was specifically knocked-out in the hematopoietic system of Vav1-Cre;Rheb1fl/fl mice(Rheb1Δ/Δ mice). Flow cytometry was used to detect the percentage of red blood cells in peripheral blood and erythroid cells in bone marrow in Vav1-Cre;Rheb1fl/fl mice and control mice. The CFC assay was used to detect the differentiation ability of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Real-time fluorescence quantification PCR was used to detect the relative expression of PU.1,GATA-1,GATA-2,CEBPα and CEBPβ of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Rapamycin was added to the culture medium, and it was used to detect the changes in cloning ability of megakaryocyte-erythroid progenitor cells from wild-type mice in vitro.@*RESULTS@#After Rheb1 was knocked out, the development and stress response ability of megakaryocyte-erythroid progenitor cells in mice were weaken and the differentiation ability of megakaryocyte-erythroid progenitor cells in vitro was weaken. Moreover, the expression of GATA-1 of megakaryocyte-erythroid progenitor cells was decreased. Further, rapamycin could inhibit the differentiative capacity of megakaryocyte-erythroid progenitor cells in vitro.@*CONCLUSION@#Rheb1 can regulate the development of megakaryocyte-erythroid progenitor cells probably through the mTOR signaling pathway in mice.

Abivertinib inhibits megakaryocyte differentiation and platelet biogenesis / 医学前沿

Abivertinib, a third-generation tyrosine kinase inhibitor, is originally designed to target epidermal growth factor receptor (EGFR)-activating mutations. Previous studies have shown that abivertinib has promising antitumor activity and a well-tolerated safety profile in patients with non-small-cell lung cancer. However, abivertinib also exhibited high inhibitory activity against Bruton's tyrosine kinase and Janus kinase 3. Given that these kinases play some roles in the progression of megakaryopoiesis, we speculate that abivertinib can affect megakaryocyte (MK) differentiation and platelet biogenesis. We treated cord blood CD34+ hematopoietic stem cells, Meg-01 cells, and C57BL/6 mice with abivertinib and observed megakaryopoiesis to determine the biological effect of abivertinib on MK differentiation and platelet biogenesis. Our in vitro results showed that abivertinib impaired the CFU-MK formation, proliferation of CD34+ HSC-derived MK progenitor cells, and differentiation and functions of MKs and inhibited Meg-01-derived MK differentiation. These results suggested that megakaryopoiesis was inhibited by abivertinib. We also demonstrated in vivo that abivertinib decreased the number of MKs in bone marrow and platelet counts in mice, which suggested that thrombopoiesis was also inhibited. Thus, these preclinical data collectively suggested that abivertinib could inhibit MK differentiation and platelet biogenesis and might be an agent for thrombocythemia.

Study on apoptosis mechanism of leukemia cells induced by bisindolylmaleimide derivative L6 / 中草药

Objective: To investigate the effect of bisindolylmaleimide derivative L6 on inducing apoptosis of leukemia cells and its molecular mechanism. Methods: MTT assay was used to determinate the killing effect of L6 on HELL, K562, and KG1a cells. Flow cytometry was used to detect the effects of L6 on apoptosis, cell cycle, and differentiation of HEL cells. Western blotting was used to detect the expression of apoptosis-related protein. Finally, the effect of L6 on leukemia mouse was studied in vivo. Results: MTT assay showed that L6 had a stronger inhibitory activity against HEL, K562, and KG1a cell lines than the positive control PKC412 compound, with IC50 of (0.05 ± 0.03), (0.32 ± 0.01), and (0.19 ± 0.10) μmol/L, respectively. L6 could induce the apoptosis, G2/M arrest, megakaryocyte differentiation of HEL cells with a dose effect. Western blotting revealed that L6 mainly performed apoptosis by activating Caspase-3, which is an apoptotic executive protein. Hematoxylin-eosin (HE) staining of liver tissue of mice showed a reduction in HEL cell infiltration, but the more significant reduction in group L6 was observed, indicating that L6 could delay the metastasis of leukemia, and its effect was better than that of PKC412. Conclusion: Bisindolylmaleimide derivative L6 has a strong anti-leukemia activity, providing new hope for the development of new leukemia drugs.

El megacariocito: una célula muy original / The megakaryocyte: a very original cell

Resumen El megacariocito es la célula más grande de la médula ósea, por lo tanto es relativamente fácil reconocer su presencia al observar un aspirado o una biopsia de este tejido. Difiere de otras células por su tamaño, por ser poliploide y crecer por endomitosis. No hay otra célula humana que crezca así. Además, tiene funciones biológicas muy importantes. La más conocida es el dar origen a las plaquetas, que son indispensables para la hemostasia y la reparación de los vasos sanguíneos dañados, así como para la cicatrización de los tejidos que rodean a las heridas. Sin embargo, en los últimos años, a los megacariocitos también se les han atribuido algunas otras funciones que discutiremos en esta revisión.

Abstract The Megakaryocyte is the biggest cell in the bone marrow; therefore, it is easy to recognize in a bone marrow aspirate. In humans, this cell differs from others because of its size, its polyploidy and because it grows by endomitosis. It is the only human cell that grows this way. In addition, the megakaryocyte has very important biological functions. Its best-known function is being in charge of the production of platelets, which are essential for hemostasis, the repair of damaged blood vessels, and healing the tissues surrounding wounds. However, in recent years, other functions have been attributed to the megakaryocyte, which will be discussed in this review.

Effects of bone marrow mesenchymal cells from immune thrombocytopenia patients on the biological behaviors of megakaryocytes / 上海交通大学学报（医学版）

Objective·To investigate changes of immune thrombocytopenia (ITP) patients-derived bone marrow mesenchymal cells (BMCs) in cells survival, cytokines expression as well as the effects of BMCs on the biological behaviors of megakaryocytes. Methods?·?BMCs were collected from 7 ITP patients and 5 normal controls (NC), and cultivated by the whole marrow adherent method. Surface markers and basal apoptosis rate of BMCs were analyzed by flow cytometry (FCM). Proliferation of BMCs was assessed by CCK-8 method. Phorbol 12-myristate 13-acetate (PMA) was used to stimulate differentiation of HEL cells. The induced HEL cells (inHEL) were divided into 3 groups: inHEL cultured alone (group a), inHEL co-cultured with BMCs derived from ITP patients (group b), inHEL co-cultured with BMCs derived from NC (group c). After 72 h incubation, the expression of cell surface proteins (CD41a, CD42b) and cell apoptosis rate were analyzed by FCM. The mRNA and proteins expression levels of cytokines IL6, IL11, TPO, SCF were detected by real-time fluorescent quantitative PCR (RT-qPCR) and enzyme linked immunosorbent assay (ELISA), respectively. Results?·?Compared with NC, BMCs from ITP patients grew progressively slowly (Day 4, P=0.039; Day 6, 10, P=0.009; Day 8, P=0.007), cell basal apoptosis rates were increased [AV+PI- (early apoptosis rate), P=0.036; AV+PI+(late apoptosis rate), P=0.003; AV+PI-/+(total apoptosis rate), P=0.004]. Compared with group a, the expression of CD41a in group c was much higher (P=0.000). The expression of CD41a in group b was higher than that in group a (P=0.015), but still much less than that in group c (P=0.000). Compared with group a, the early and total apoptosis rate in group b, c and the late apoptosis rate in group c were decreased obviously (all P=0.000), whereas there was no obvious change of the late apoptosis rate in group b. However, compared with group c, the late and total apoptosis rate in group b were significantly increased (both P=0.000). The expression levels of IL6, SCF mRNA and IL6 protein were significantly decreased in ITP BMCs (all P=0.000), but there was no obvious difference in the expression levels of IL11 and TPO between ITP BMCs and NC BMCs. Conclusion?·?BMCs from ITP patients show some defects in supporting megakaryocytic differentiation and survival under co-culture conditions, which mechanisms are related to the reduction of IL6 and SCF expression.

Effects of bone marrow mesenchymal cells from immune thrombocytopenia patients on the biological behaviors of megakaryocytes / 上海交通大学学报（医学版）

Objective • To investigate changes of immune thrombocytopenia (ITP) patients-derived bone marrow mesenchymal cells (BMCs) in cells survival, cytokines expression as well as the effects of BMCs on the biological behaviors of megakaryocytes. Methods • BMCs were collected from 7 ITP patients and 5 normal controls (NC), and cultivated by the whole marrow adherent method. Surface markers and basal apoptosis rate of BMCs were analyzed by flow cytometry (FCM). Proliferation of BMCs was assessed by CCK-8 method. Phorbol 12-myristate 13-acetate (PMA) was used to stimulate differentiation of HEL cells. The induced HEL cells (inHEL) were divided into 3 groups: inHEL cultured alone (group a), inHEL co-cultured with BMCs derived from ITP patients (group b), inHEL co-cultured with BMCs derived from NC (group c). After 72 h incubation, the expression of cell surface proteins (CD41a, CD42b) and cell apoptosis rate were analyzed by FCM. The mRNA and proteins expression levels of cytokines IL6, IL11, TPO, SCF were detected by real-time fluorescent quantitative PCR (RT-qPCR) and enzyme linked immunosorbent assay (ELISA), respectively. Results • Compared with NC, BMCs from ITP patients grew progressively slowly (Day 4, P=0.039; Day 6, 10, P=0.009; Day 8, P=0.007), cell basal apoptosis rates were increased [AV+PI- (early apoptosis rate), P=0.036; AV+PI+ (late apoptosis rate), P=0.003; AV+PI-/+ (total apoptosis rate), P=0.004]. Compared with group a, the expression of CD41a in group c was much higher (P=0.000). The expression of CD41a in group b was higher than that in group a (P=0.015), but still much less than that in group c (P=0.000). Compared with group a, the early and total apoptosis rate in group b, c and the late apoptosis rate in group c were decreased obviously (all P=0.000), whereas there was no obvious change of the late apoptosis rate in group b. However, compared with group c, the late and total apoptosis rate in group b were significantly increased (both P=0.000). The expression levels of IL6, SCF mRNA and IL6 protein were significantly decreased in ITP BMCs (all P=0.000), but there was no obvious difference in the expression levels of IL11 and TPO between ITP BMCs and NC BMCs. Conclusion • BMCs from ITP patients show some defects in supporting megakaryocytic differentiation and survival under co-culture conditions, which mechanisms are related to the reduction of IL6 and SCF expression.

Quantitive assessment of bone marrow trephan biopsy / Шинэ санаа Шинэ нээлт

In United States, person is diagnosed with blood cancer in every 3 minutes. In 2015, there were 1.665.540 total cancer cases and 9.4% of them lymphoma and leukemia . In 2015, there were 95 cases of lymphoma in Mongolia when compared 4 times increase to 2015 from 2010 . Bone marrow examination is an established diagnostic modality in the evaluation of various hematological disorders. BM examination can serve to establish or confirm a primary diagnosis of lymphoma or to determine the extent of disease dissemination for staging purposes. Biopsy is essential for diagnosis in a dry tap or blood tap which occurs when the marrow is fibrotic or densely cellular. Only a biopsy allows a complete assessment of marrow architecture and pattern of distribution of any abnormal infiltrates. In 2015.01-2016.01 fifty five bone marrow biopsies were retrieved from the files of the National First Clinical Hospital-Department of Hematology. These all statistical analysis was performed using by SPSS 17. Bone marrow processing and staining: The hematologist is instructed to place the freshly obtained BMTB specimens directly into buffer substance fixative and transport it immediately to the histopathology department, on the same day as the procedure.The next morning (after 20–24 h), the solution is decanted (with a strainer) and the biopsy specimen is washed in distilled water for 30 min. The biopsy specimens are left to decalcify for about 6 h before being processed and embedded in paraffin wax, with procedures similar as for other specimens.Sections, 1-mm thick (microtome set for 1 mm sections), are cut from the paraffin-wax blocks with the routine rotary microtomes in the laboratoryA total of 55 cases were reviewed from December 2014 to November 2015. The age of the subjects ranged from twenty two years to seventy eigth years with a male predominance (1.7:1). Data of 55 trephine biopsies were reviewed. The percentage of trephine biopsies in different length ranges was calculated. Twenty two biopsieswere of recommended length, i.e., ≥1.5 Cm while remaining 33 were less than the recommended length. The rate of positivity for diagnosis was 95.4% in group-1, 94.1% in group-2, 63.6% in group-3 and 40% in group-4 In all cases in our study 73% (n=40) were satisfactory and 27%(n=15) unsatisfactory slides .Our study showed that 40% trephan biopsies were of revommended length i.e >=1.5cm with 95.4% positive of diagnosis. However biopsies measuring 1-1.4 cm also had comparable result 94.1% .

Effects of panaxadiol saponins component as a new Chinese patent medicine on proliferation, differentiation and corresponding gene expression profile of megakaryocytes / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of panaxadiol saponins component (PDS-C) isolated from total saponins of panax ginseng on proliferation, differentiation and corresponding gene expression profile of megakaryocytes.</p><p><b>METHODS</b>Bone marrow culture of colony forming assay of megakaryocytic progenitor cells (CFU-MK) was observed for the promoting proliferation mediated by PDS-C, and differentiation of megakaryocytic blasts caused by PDS-C was analyzed with flow cytometry in CHRF-288 and Meg-01 cells, as well as proliferation, differentiation-related genes expression profile and protein expression levels were detected by human gene expression microarray and western blot.</p><p><b>RESULTS</b>In response to PDS-C 10, 20 and 50 mg/L, CFU-MK from 10 human bone marrow samples was increased by 28.9%±2.7%, 41.0%±3.2% and 40.5%±2.6% over untreated control, respectively (P <0.01, each). Flow cytometry analysis showed that PDS-C treated CHRF-288 cells and Meg-01 cells significantly increased in CD42b, CD41, TSP and CD36 positive ratio, respectively. PDS-C induced 29 genes up-regulated more than two-fold commonly in both cells detected by human expression microarray representing 4000 known genes. The protein expression levels of ZNF91, c-Fos, BTF3a, GATA-1, RGS2, NDRG2 and RUNX1 were increased with western blot in correspond to microarray results.</p><p><b>CONCLUSION</b>PDS-C as an effective component for hematopoiesis, play the role to enhance proliferation and differentiation of megakaryocytes, also up-regulated expression of proliferation, differentiation-related genes and proteins in vitro.</p>

Study on micromegakaryocytes of patients with myelodysplastic syndrome by flow cytometry / 重庆医学

Objective To setup a measurement of human bone marrow micromegakaryocyte which based on CD41a and PI double‐labeled flow cytometric analysis ,and study the significance in the diagnosis of MDS .Methods In 42 cases of MDS patients , their bone marrow megakaryocytes were obtained by Percoll density gradient separation medium .The megakaryocyte glycoproteinⅡb/Ⅲa(CD41a)were marked with fluorescein isothiocyanate through its corresponding monoclonal antibody ,and their DNA were marked with PI .Then the megakaryocyte ploidy was analyzed by flow cytometry(FCM ) .Results The method for micromegakaryo‐cyte identification and analysis was established .In 42 patients with MDS ,the detection rate of micromegakaryocyte was 90 .5 per‐cent by FCM analysis ,but only 54 .8 percent by Wright‐Giemsa staining test and 64 .3 percent by immunohistochemistry ,the differ‐ence among them was statistically significant(χ2 = 13 .640 ,P= 0 .001) .The 42 patients with MDS were divided into two groups (low‐risk group and high‐risk group) .The detection rates of micromegakaryocyte were 81 .8 percent in low‐risk group and 100 per‐cent in high‐risk group separately by FCM analysis ,the difference was statistically significant(χ2 =4 .019 ,P=0 .045) .Conclusion The detection rate of micromegakaryocyte by FCM with CD41a and PI double marker is higher than that by cytochemical staining . The detection rate of micromegakaryocyte in the high‐risk group is higher than that of the low‐risk group ,which shows that the de‐tection of micromegakaryocyte is of great significance for MDS prognosis assessment .

Apoptosis: role in myeloid cell development

Hematopoiesis is the process that generates blood cells in an organism from the pluripotent stem cells. Hematopoietic stem cells are characterized by their ability to undergo self-renewal and differentiation. The self-renewing ability ensures that these pluripotent cells are not depleted from the bone marrow niche. A proper balance between cell death and cell survival is necessary to maintain a homeostatic condition, hence, apoptosis, or programmed cell death, is an essential step in hematopoiesis. Recent studies, however, have introduced a new aspect to this process, citing the significance of the apoptosis mediator, caspase, in cell development and differentiation. Extensive research has been carried out to study the possible role of caspases and other apoptosis related factors in the developmental processes. This review focuses on the various apoptotic factors involved in the development and differentiation of myeloid lineage cells: erythrocytes, megakaryocytes, and macrophages.

Predictive value of megakaryocytes in bo ne marrow for therapeutic response of severe thrombocyto-penia in patients with systemic lupus erythematosus / 中华风湿病学杂志

Objective To explore the value of bone marrow megakaryocyte counts in predicting clinical response of thrombocytopenia (TP) in systemic lupus erythematosus (SLE) patients. Methods Thirty-one patients of SLE with severe TP (platelet ≤50×109/L) from Peking Union Medical College Hospital during 2007 to 2014 with appreciable bone marrow aspiration results were retrospectively analyzed. Their therapeutic responses were stratified and the correlation with clinical and laboratory findings including the megakaryocyte counts in bone marrow were evaluated with logistic multivariate regression. Results Totally fifteen patients obtained complete response (CR), eight patients obtained partial response (PR) and eight no response (NR). Megakaryocyte counts in bone marrow were (101±26)/slide, (156±48)/slide and (34±15)/slide respectively with statistically significant difference (χ2=6.632, P=0.036). Those NR patients had less megakaryocytes in their bone marrow compared with those with clinical response (CR+PR) (Z=-2.438, P=0.015). By ROC curve method, we found 20/slide might be a good cutoff of megakaryocyte counts in bone marrow for determining the therapeutic response of immunotherapy with a sensitivity of 91% and a specificity of 63% and a AUC (area under the curve) of 0.793. Those with 20/slide or less megakaryocytes in bone marrows only had a clinical effective response rate of 29% verse a response rate of 88% in those with more megakaryocytes in bone marrow. Conclusion Megakaryocyte counts in bone marrow may provide predictive value for therapeutic response of severe TP in SLE patients. Those patients with equal or less than 20/slide megakaryocytes in their bone marrow tend to have poor therapeutic response.

Effect of simulated microgravity on proliferation and differentiation of the human megakaryocyte cell / 实用医学杂志

Objective To investigate the effect of simulated microgravity on the proliferation and differentiation of the human megakaryocyte cells in vitro. Methods The fourth generation rotating cell culture system (RCCS-4) was used to generate the simulated microgravity environment. The cell viability was assessed by trypan blue staining method. The proliferation of cells was assessed by cell counting method and CCK8 method. The CD41+/CD61+ cells rate and the cells cycle were detected by flow cytometry. The expression levels of thrombopoietin receptor (c-mpl) and transcription factors were detected with RT-PCR. Results After 24, 48, 72 h, culture under simulated microgravity resulted in a significant decrease in the cell number , proliferative activity, cells in the G2/M phase and levels of c-mpl mRNA expression in comparison with that under the normal gravity (P < 0.05). After 48 h and 72 h culture, CD41+/CD61+ cells ratio decreased and RUNX-1 mRNA expression was down-regulated in cells of the group SMG compared with that of the group NG (P < 0.05). Conclusion Microgravity can inhibit the proliferation and differentiation of human megakaryocyte cells in vitro. The mechanism may be that TPO/c-mpl pathway was inhibited by down regulating the expression of c-mpl which transcriptional inhibition lead to.

Clinical Study on Treatment of Chronic Idiopathic Thrombocytopenic Purpura by Expelling Wind, Cooling Blood and Invigorating Kidney Prescription / 中国中医药信息杂志

Objective To observe the effect of expelling wind, cooling blood and invigorating kidney prescription on the marrow megakaryocyte differentiation maturity and TGF-β1 in patients with chronic idiopathic thrombocytopenic purpura (CITP). Methods Fifty CITP patients were randomly divided to three groups, including 20 patients administrated with the expelling wind, cooling blood and invigorating kidney prescription as TCM group, 15 patients with the same decoction and prednisone as combine group, and 15 patients with prednisone as western medicine group, 4 weeks as one treatment course. After 3 courses, the change of platelet counts, marrow megakaryocyte amount, platelet-produced megakaryocyte proportion and TGF-β1 level in the marrow were observed. Results The fine efficiency of TCM group (55.0%, 11/20) excelled western medicine group (20.0%, 3/15) significantly and close to that of combine group (60.0%, 9/15). Platelet counts of TCM group was raised obviously after treatment (P<0.01), better than that of western medicine group (P<0.05), and was similar to that of combine group. The marrow megakaryocyte amount of TCM group was effectively decreased and the platelet-produced megakaryocyte proportion was increased greatly (P<0.01), similar to that of combine group, which of western medicine group had no significant difference between pre-therapy and post-therapy. TGF-β1 of TCM group and combine group degraded obviously (P<0.05) compared with that before treatment, and was significant deviation compared with that of western medicine group (P<0.05). Conclusion The expelling wind, cooling blood and invigorating kidney prescription can effectively degrade the value of TGF-β1 of CITP patients, facilitate the maturity of the marrow megakaryocyte amount and raise the platelet counts.

The impact of bone marrow megakaryocyte to clinical and immunological characteristics of thrombocytopenia in systemic lupus erythematosus / 中华风湿病学杂志

Objective To investigate the clinical significance.of thrombocytopenia in systemic lupus erythematosus (SLE).Methods One hundred and two SLE patients with thrombocytopenia who were admitted to Peking University People's Hospital were involved in the study.SLE patients without thrombocytopenia were controls.Clinical and laboratory characteristics were analyzed.T-test and Chi-square test were used for inter-group comparison.Results Patients with thrombocytopenia had more organ damage than those without,although the disease activities (SLEDAI) were not different between these two groups.Bone marrow characteristics were analyzed and 16 patients were amegakaryocytic.However,there were no differences observed between patients with amegakaryocytosis and normal megakaryocytes in organ damage,disease activity and response to therapy.Conclusion Lupus patients with thrombocytopenia usually have more organ damage.About 32％ of those patients are amegakaryocytosis.

Effect of exposure to extremely low electro-magnetic field during prenatal period on mice spleen.

Total body weight of newborns, the volume of spleen, and the number of megakaryocytes decreased following the exposure to ELF-MF (6x10-3 T and 50 Hz) at 1-5, 6-10, 11-15, and 16-20 days of pregnancy of mice. The complete period of gestation was sensitive to ELF-MF exposure; the initial days were more prone to exposure. The results suggest that the use of ELF-MF producing instruments should be limited during gestation.

Ex vivo Expansion and Clonal Maintenance of CD34+ Selected Cells from Cord Blood and Peripheral Blood / 소아과

PURPOSE: Because of the unavailability of marrow transplantation, umbilical cord blood (CB) is increasingly being used. We evaluated the potential of ex vivo expansion and clonality in CD34+ cells separated from cord blood source and mobilized peripheral blood (PB) in a serum-free media. METHODS: The CD34+ cells, selected from CB and mobilized PB, were expanded with hematopoietic growth factors. They were then cultured for burst-forming units of erythrocytes (BFU-E), colony-forming units of granulocytes and monocytes (CFU-GM) and colony-forming units of megakaryocytes (CFU-Mk) at culture days 0, day 4, day 7, and day 14 with various growth factors. RESULTS: The CB-selected CD34+ cells showed significantly higher total cell expansion than those from the PB at day 7 (2 fold increase than PB). The CB-selected CD34+ cells produced more BFU-E colonies than did the PB on culture at days 7 and at day 14. Also, the CB-selected CD34+ cells produced more CFU-Mk colonies than did the PB on culture at day 4 and at day 7. CONCLUSION: The ex vivo expansion of the CB cells may be promising in producing total cellular expansion, CFU-Mk and BFU-E compared with PB for 7 to 14 days. The growth factors combination including megakaryocyte growth and development, flt3-ligand and interleukin-3 showed more expansion in the view of total cells and clonal maintenance compared with less combination.