1.Research Status of TPO/c-MPL Signaling Pathway in Acute Myeloid Leukemia--Review.
Journal of Experimental Hematology 2021;29(4):1351-1354
Thrombopoietin (TPO) can activate hematopoietic cell proliferation by its receptor c-MPL mediated downstream pathways and induce the generation of megakaryocyte. In recent years, domestic and foreign researches have confirmed that TPO/ c-MPL pathway also plays an important role in the self-renewal and quiescence of leukemia stem cell, and its expression in acute myeloid leukemia (AML) also indicates the chemotherapy resistance and poor prognosis. In this article, the research progress of the roles of TPO/c-MPL pathway in chemotherapy resistance, prognosis of AML patients, and the application of TPO/ c-MPL receptor agonists in AML were summarized briefly.
Humans
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Leukemia, Myeloid, Acute
;
Neoplasm Proteins
;
Proto-Oncogene Proteins/metabolism*
;
Receptors, Cytokine
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Receptors, Thrombopoietin
;
Signal Transduction
;
Thrombopoietin
2.Identification of a novel aberrant spliceosome of MPL gene (MPLL391-V392ins12)in patients with myeloproliferative neoplasms.
Ruiyuan TIAN ; Xiuhua CHEN ; Jianmei CHANG ; Na ZHANG ; Yanhong TAN ; Zhifang XU ; Fanggang REN ; Junxia ZHAO ; Jie PAN ; Haixiu GUO ; Xiaojuan WANG ; Hongwei WANG
Chinese Journal of Hematology 2015;36(7):559-562
OBJECTIVETo identify the MPL L391-V392ins12 spliceosome and analyze its frequencies in patients with myeloproliferative neoplasms (MPN).
METHODSMPL aberrant spliceosome was identified through reverse transcription polymerase chain reaction (RT-PCR)combined with cloning sequencing. The mutation of this spliceosome in 248 MPN patients and 200 normal people was determined by allele-specific polymerase chain reaction (AS-PCR).
RESULTSA novel aberrant spliceosome of MPL gene (MPL L391-V392ins12)was identified, i.e. 36 bp intron was retained between exon7 and exon8, and there were 12 amino acids (EGLKLLPADIPV)inserted. MPL L391-V392ins12 mutation was detected in 19 (7.66%)of the 248 patients with MPN, including 1 (1.92%) of 52 patients with PV, 14 (9.66%) of 145 with ET, and 4 (7.84%) of 51 with PMF. And the mutation was not detected in the group of 200 normal people.
CONCLUSIONMPL L391-V392ins12 spliceosome is an aberrant spliceosome present in the MPN. It can be detected in PV, ET and PMF, and more frequently in ET and PMF. This mutation may play an important role in the process of MPN.
Humans ; Mutation ; Myeloproliferative Disorders ; genetics ; Neoplasms ; genetics ; Polymerase Chain Reaction ; Receptors, Thrombopoietin ; genetics ; Spliceosomes
3.Clinical Characteristic of "triple-negative" Essential Thrombocythaemia Patients and Mutation Analysis by Targeted Sequencing.
Man-Kai JU ; Rong-Feng FU ; Hui-Yuan LI ; Xiao-Fan LIU ; Feng XUE ; Yun-Fei CHEN ; Yue-Ting HUANG ; Li-Yan ZHANG ; Ren-Chi YANG ; Lei ZHANG
Journal of Experimental Hematology 2018;26(4):1137-1145
BACKGROUNDEssential thrombocythemia is a subgroup of myeloproliferative neoplasms. Previous studies identified mutations of JAK2, CALR, and MPL that are closely related with the pathogenesis of myeloproliferative neoplasms. All these mutations contribute to the hyperactivation of JAK2/STAT pathway. However, a small proportion of essential thrombocythemia patients does not display such mutations. The pathogenesis of "triple-negative" form of essential thrombocythemia remains unknown.
OBJECTIVETo investigate the clinical characteristics of triple-negative essential thrombocythemia and related mutation genes.
METHODSTo identify the mutations associated with triple-negative essential thrombocythemia, next-generation sequencing was used to conduct targeted sequencing of 360 genes in samples from 68 patients.
RESULTSAt least one missense mutation was detected in all the patients and all the detected genes. After screening the data, it was observed that 10 genes with the 10 highest mutation were follows: FLT3, SH2B3, ASXL1, ADAMTS1, TET2, TP53, EGFR, CUX1, GATA2, and MPL.When only rare genes (i.e., with a frequency in Asian populations lower than 5%, as estimated by the 1000 Genomes Project) were analyzed, the most frequently mutated genes in the patients were TET2 (33.82%), SH2B3(29.41%), and ASXL1 (23.53%). Our study identified some mutations that did not previously reported. Although all these mutations need further validation, high incidence rates may indicate relevance of the respective mutations to essential thrombocythemia pathogenesis. Some of the detected mutations have been previously reported; these mutations were also found in a large proportion of our subjects.
CONCLUSIONwhole-exon sequencing can provide a higher level of accuracy for gene mutation analysis and assist in identifying mutations that contribute to illustrate the pathogenesis of essential thrombocythemia.
Calreticulin ; DNA Mutational Analysis ; Humans ; Janus Kinase 2 ; Mutation ; Myeloproliferative Disorders ; Receptors, Thrombopoietin ; Thrombocythemia, Essential
4.Detection and Diagnostic Values of JAK2, CALR, MPL Gene Mutations in 208 Cases of BCR/ABL1 Negative Chronic Myeloproliferative Diseases.
Zhen-Ling LI ; Li GAO ; Hui ZHANG ; Chun-Xia ZHANG ; Yan-Rong CHEN ; Fan-Zhou HUANG ; Ming GONG ; Ya-Yue GAO ; Yin TANG ; Yi-Gai MA
Journal of Experimental Hematology 2018;26(4):1122-1128
OBJECTIVETo detect the JAK2, CALR and MPL gene mutations in patients with BCR/ABL1 negative chronic myeloproliferative diseases(BCR/ABL1-CMPD)and to evaluate their diagnostic value.
METHODSTwo hundred and eight cases of BCR/ABL1-CMPD comprising of 146 cases of essential thrombocythemia(ET), 37 cases of polycythemia vera(PV)and 25 cases of primary myelofibrosis(PMF)from March 2012 to December 2015 were enrolled in the BCR/ABL1-CMPD, while 124 cases of secondary thrombocythemia and 73 cases of secondary polycythemia were enrolled in the control group. The genomic DNA and total RNA Were isolated from bone marrow or peripheral blood, then the exons 12 to 20 of JAK2 gene, exon 10 of MPL gene and exons 3 to 9 of CALR gene were analyzed by using DNA sequencing.
RESULTSamong 146 ET patients, the JAK2, CALR or MPL mutations were found in: 138 cases(94.5%)including 86 cases with JAK2V617F mutation(58.9%)and 2 cases(1.4%)with exon 12 of JAK2 mutations. CALR mutations were detected in 41 cases(28.1%), among them type 1(c.1092_1143del)in 22 cases, type 2(c.1154_1155insTTGTC)in 11 cases, and type 5(c. 1091_1142del), type 8(c.1104_1137del), type 41(c.1107_1137del), type 42(c.1125_1125del)in one case respectively. In addition, 4 cases were detected withother mutations of the CALR gene(c.1107_1115del, c.1111_1144 del, c.1101 A>C, c.1112_1117del). Moreover, 9 cases harbored MPL mutations(6.2%). Secondly, 31 patients were detected with JAK2V617F mutation(83.8%)in 37 cases of PV, and JAK2 exon 12 mutations were found in 2 cases(5.4%). Besides, CALR mutations were detected in 2 cases(5.4%), including 1 case of type I, the other of novel mutation of CALR. Thirdly, 19 in 25 cases of PMF were detected with JAK2V617F mutation(76%), 2 cases with CALR mutations(8%). 4 patients(16%), JAK2, CALR or MPL mutations were not detected, but among them 3 cases were found harboring other genetic abnormalities. Fourthly, no mutations of JAK2, MPL and CALR genes were detected in 124 patients with secondary thrombocytosis and 73 cases with secondary polycythemia.
CONCLUSIONCombined detection of JAK2, CALR and MPL gene mutations can cover the vast majority of patients with BCR/ABL1-negative myeloproliferative neoplasms. For higher frequencies of the mutations of CALR in ET patients, CALR mutation can be used as a new diagnostic marker in ET patients with JAK2 and MPL wild type.
Calreticulin ; Humans ; Janus Kinase 2 ; Mutation ; Myeloproliferative Disorders ; Polycythemia Vera ; Receptors, Thrombopoietin ; Thrombocythemia, Essential
5.Mutation Rate and Clinical Characteristics of CALR, JAK2 V617F and MPL W515K Genes in Patients With Primary Thrombocythemia.
Xiao-Wan YU ; Dong-Hong HUANG ; Jian-Xin GUO ; Yue-Qin HUANG ; Ruo-Teng XIE ; Jun-Feng CAI
Journal of Experimental Hematology 2018;26(3):866-870
OBJECTIVETo analyze the mutation rate and clinical characteristics of CALR, MPL W515K and JAK2 V617F genes in patients with primary thrombocythemia (PT).
METHODSFifty-six patients with PT were selected as the research objects in our hospital. The CALR and MPL W515K gene mutations were determined by genomic DNA-PCR direct sequencing of the PCR products, and the JAK2 V617F gene mutation was detected by allele specific PCR method.
RESULTSAmong the 56 patients with PT there were 14 cases of CALR gene mutation with the incidence rate of 25%, including 6 cases of type I, 5 cases of type II and 3 cases of type III. The sex, age, platelet(Plt) count, white blood cell (WBC) count and hemoglobin (Hb) level in the type I case of CALR gene mutation all were not significantly different from that in type II and III(all P>0.05); the WBC level in type III group significantly increased in comparison of type II group (P<0.05), while the sex, age, Hb and Plt levels showed no significant difference between the type III and type II groups (P>0.05). There were 3 cases of MPL W515K gene mutation with the incidence rate of 5.36%; 21 cases of JAK2 V617F gene mutation with the incidence rate of 37.50%. There were 13 cases of CALR gene mutation in negative patients with MPL W515K and JAK2 V617F (18 cases) with 72.22% incidence rate (13/18), and there was no cases of 1 or 2 gene mutations coexisted. The levels of Hb and WBC in peripheral blood of patients with CALR mutation were significantly lower than those of JAK2 V617F mutation (both P<0.05). In 56 cases, there were 3 cases of abnormal karyotype, with the incidence rate of 5.36%. The mutation rate of CALR gene in abnormal karyotypes (66.67%) was significantly higher than that of normal karyotypes (20.75%) (P<0.01).
CONCLUSIONThe incidence of JAK2 V617F gene mutation increases in the patients with primary thrombocythemia; CALR mutation rate is higher in the patients with negative MPL W515K and JAK2 V617F gene mutation, which may closely correlate with abnormal karyotype; the levels of peripheral Hb and WBC in PT the patients with CALR gene mutation are significantly lower than those in patients with JAK2 V617F mutation.
Calreticulin ; Humans ; Janus Kinase 2 ; Mutation ; Mutation Rate ; Receptors, Thrombopoietin ; Thrombocythemia, Essential
6.Detection of Genetic Mutations in Primary Hypereosinophilia Patients.
Jie ZHOU ; Hao WU ; Bing LI ; Ai-Bin LIANG ; Jian-Fei FU
Journal of Experimental Hematology 2019;27(2):504-508
OBJECTIVE:
To explore the potential pathogenetic mutations of primary hypereosinophilia(HEN)by sequencing FGFR1 FLT3, MPL and JAK2 genes, and to clarify their effect on clinical manifestation and prognosis of HEN patients.
METHODS:
The direct DNA sequencing was employed to detect the gene mutations of FGFR1, FLT3, MPL and JAK2 in HEN patients.
RESULTS:
One deletion mutation (2654_2753del) within tyrosine kinase domain of FLT3 gene was found in a patient suffered from severe symptoms and ended with dismal outcome, which induced a premature stop codon (G885fsX888). For FGFR1, a new variation described as 1014_1019del AACAGT for nucleotide change was found in 19 cases, resulting in T339_V340del at the protein level.
CONCLUSION
The deletion of 6 bases in the FGFR1 gene (1014_1019del AACAGT) is first reported as non-synonymous SNP (nsSNP) site in the patients with primary hypereosinophilia. Deletion mutations in the FLT3 gene may be related with malignant clinical features and poor prognosis.
Base Sequence
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Humans
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Hypereosinophilic Syndrome
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genetics
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Mutation
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Receptors, Thrombopoietin
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Sequence Deletion
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fms-Like Tyrosine Kinase 3
7.Effect of rhTPO to the Proliferation and Apoptosis of Acute Myeloid Leukemia Cell Lines.
Nan WANG ; Na LYU ; Xin MIN ; Li-Li WANG ; Hai-Yan ZHU
Journal of Experimental Hematology 2021;29(2):389-394
OBJECTIVE:
To investigate the effects of recombinant human thrombopoietin (rhTPO) to proliferation and apoptosis of acute myeloid leukemia (AML) cell lines.
METHODS:
After the treatment of different concentrations of rhTPO (0, 50, 100 ng/ml) for different time (24,48,72 h),the cell proliferation rates of the AML cell lines (Kasumi-1, Skno-1, HEL, HL-60, THP-1) were determined by CCK-8 method. Apoptosis rate of each cell line cocultured with rhTPO was detected by Annexin V/PI method. The relative expression of TPO receptor c-MPL (myeloproliferative clonal antibody) mRNA in AML cell lines was detected by Q-PCR. The expression of c-MPL protein in each cell line was detected by Western blot. The expression of c-MPL antigen in HL-60 cells treated by different concentrations of rhTPO was detected by Flow cytometry.
RESULTS:
RhTPO showed no promotion to the proliferation of Kasumi-1, Skno-1, HEL, HL-60, THP-1 cell lines,however,it showed inhibitory effect to cell proliferation (72 h 0 ng/ml vs 100 ng/ml, P= 0.029) and pro-apoptotic (48 h 0 ng/ml vs 50 ng/ml, P=0.0143) in HL-60 cells. In Kasumi-1, Skno-1, HEL and THP-1 cells, there showed no statistically significant differences in apoptosis rate among each groups treated by different concentrations of rhTPO. Each AML cell line showed different levels of c-MPL gene and c-MPL protein expression, but HEL cells showed the highest expression in both of them. After HL-60 cells were treated by different concentrations of rhTPO for 48 hours, there showed no statistical difference in c-MPL antigen expression among each groups.
CONCLUSION
RhTPO can not promote the proliferation of Kasumi-1, Skno-1, HEL, HL-60 and THP-1 leukemia cell lines. On the contrary, rhTPO can inhibit HL-60 cell proliferation and promote its apoptosis, and this effect is not related to c-MPL gene expression or protein expression.
Apoptosis
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Cell Proliferation
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Humans
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Leukemia, Myeloid, Acute
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Neoplasm Proteins
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Proto-Oncogene Proteins
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Receptors, Cytokine
;
Thrombopoietin
8.Effect of 5-hydroxtryptamine on megakaryocytopoiesis--review.
Yuan-Shan CHENG ; Yuan-Sheng LIU ; Mo YANG
Journal of Experimental Hematology 2006;14(2):403-407
5-hydroxtryptamine (5-HT, serotonin) has been recognized not only as a neurotransmitter and vasoactive agent, but also as a growth factor. 5-HT mainly binds to 5-HT(2) receptors or 5-HT(1) receptors on cell surface to stimulate cell proliferation through Ras or MAPK pathway in many cell types. It has been reported that 5-HT stimulates megakaryocytopoiesis via 5-HT receptors. The possible mechanism of 5-HT on the proliferation and differentiation of megakaryocytes (MK) has been discussed in this review article. In early stage of megakaryocytopoiesis, 5-HT may bind to 5-HT(2B) receptor on megakaryocytes, and promotes their proliferation and differentiation. In the late stage, 5-HT may involve in the platelet release procedure by inducing nitric oxide (NO) synthesis via 5-HT(2A) receptors. 5-HT can also antagonize the apoptotic effect induced by thrombospondin-1 (TSP-1) which is a platelet alpha granule protein and has synergic effect with platelet-derived growth factor (PDGF) to enhance megakaryocytes proliferation. Therefore, 5-HT is likely to be an important substance in the feedback regulation of thrombopoiesis. In this review the 5-HT and its receptors, 5-HT as cell growth factor, pathway of 5-HT stimulating cell proliferation and influance of 5-HT on MK-progenitor cells were summarized.
Humans
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Megakaryocytes
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physiology
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Receptors, Serotonin
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metabolism
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Receptors, Serotonin, 5-HT2
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metabolism
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Serotonin
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metabolism
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pharmacology
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Thrombopoiesis
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physiology
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Thrombopoietin
;
physiology
9.Identification of TPO receptors on central nervous system-a preliminary report.
Mo YANG ; Wen-Jie XIA ; Karen LI ; Nga-Hin PONG ; Ki-Wai CHIK ; Chi-Kong LI ; Margaret H L NG ; Ho-Keung NG ; Kwok-Pui FUNG ; Tai-Fai FOK
Journal of Experimental Hematology 2004;12(4):494-497
To identify the expression of thrombopoietin (TPO) receptors (c-mpl) on central nervous system (CNS) and to evaluate the role of TPO on neural cell proliferation and protection, immunohistochemical staining, RT-PCR, MTT, and annexin-V methods were used in this study. The results showed the expression of TPO receptor on human CNS and murine neural cells. C-mpl mRNA was identified in human cerebral hemispheres and cerebellum, and mouse neural cell line C17.2 by RT-PCR. C-mpl was also confirmed in human cerebral hemispheres by immunohistostaining with con-focal microscopy. Furthermore, TPO had a stimulating effect on the growth of in vitro neural cell C17.2 by MTT assay. The anti-apoptotic effect of TPO on C17.2 cells was also demonstrated by staining with annexin-V and PI. In conclusion, the first evidence showed the expression of TPO receptor c-mpl in central nervous system. Moreover, the effect of TPO on neural cell proliferation and anti-apoptosis was also demonstrated on in vitro neural cells.
Animals
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Apoptosis
;
drug effects
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Brain Chemistry
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Cell Line
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Cell Proliferation
;
drug effects
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Erythropoietin
;
pharmacology
;
Humans
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Mice
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Neoplasm Proteins
;
analysis
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Neurons
;
drug effects
;
Oncogene Proteins
;
analysis
;
Proto-Oncogene Proteins
;
analysis
;
Receptors, Cytokine
;
analysis
;
Receptors, Thrombopoietin
;
Thrombopoietin
;
pharmacology
10.Switching between eltrombopag and recombinant human thrombopoietin in patients with immune thrombocytopenia: an observational study.
Xuan CAI ; Haixia FU ; Xiangyu ZHAO ; Jin LU ; Qian JIANG ; Yingjun CHANG ; Xiaojun HUANG ; Xiaohui ZHANG
Chinese Medical Journal 2022;135(19):2344-2350
BACKGROUND:
Recombinant human thrombopoietin (rh-TPO) and eltrombopag are two distinct TPO receptor agonists (TPO-RAs) with different mechanisms. During the pandemic, when immunosuppressive medications are controversial, switching to another TPO-RA may be worth exploring in patients who do not benefit from their first TPO-RA. We investigated the outcomes of switching from rh-TPO to eltrombopag or vice versa in immune thrombocytopenia (ITP) patients.
METHODS:
This prospective, open-label, observational investigation included 96 adult ITP patients who needed to switch between rh-TPO and eltrombopag between January 2020 and January 2021 at Peking University People's Hospital in China. The study evaluated response rates and platelet counts at different time points after the switch, bleeding events, time to response, duration of response, and adverse events.
RESULTS:
At 6 weeks after switching, response was observed in 21/49 patients (43%) who switched for inefficacy and 34/47 patients (72%) who switched for non-efficacy-related issues. In the inefficacy group, 9/27 patients (33%) responded to eltrombopag, and 12/22 patients (55%) responded to rh-TPO. In the non-efficacy-related group, 21/26 (81%) and 13/21 (62%) patients in the eltrombopag and rh-TPO groups maintained their response rates at 6 weeks after switching, respectively. Response at 6 months was achieved in 24/49 patients (49%) switching for inefficacy and 37/47 patients (79%) switching for non-efficacy issues. In the inefficacy group, 13/27 patients (48%) responded to eltrombopag, and 11/22 patients (50%) responded to rh-TPO. In the non-efficacy-related group, 22/26 patients (85%) and 15/21 patients (71%) in the eltrombopag and rh-TPO groups maintained their response rates at 6 months after switching, respectively. Both eltrombopag and rh-TPO were well tolerated.
CONCLUSIONS:
Our study confirmed the safety and effectiveness of switching between rh-TPO and eltrombopag for ITP patients who had no response to or experienced adverse events with their first TPO-RA. When the switch was motivated by other reasons, including patient preference and platelet count fluctuations, the probability of response was high.
REGISTRATION
ClinicalTrials.gov, NCT04214951.
Adult
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Humans
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Purpura, Thrombocytopenic, Idiopathic
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Thrombopoietin/adverse effects*
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Prospective Studies
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Recombinant Fusion Proteins
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Receptors, Fc/therapeutic use*
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Receptors, Thrombopoietin/therapeutic use*
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Thrombocytopenia/chemically induced*
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Benzoates/adverse effects*
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Hydrazines/adverse effects*