1.A truncated N protein-based ELISA method for the detection of antibodies against porcine deltacoronavirus.
Dongsheng WANG ; Ruiming YU ; Liping ZHANG ; Yingjie BAI ; Xia LIU ; Yonglu WANG ; Xiaohua DU ; Xinsheng LIU
Chinese Journal of Biotechnology 2025;41(7):2760-2773
This study aims to establish an antibody detection method for porcine deltacoronavirus (PDCoV). The recombinant proteins PDCoV-N1 and PDCoV-N2 were expressed via the prokaryotic plasmid pColdII harboring the N gene sequence of the PDCoV strain CH/XJYN/2016. The reactivity and specificity of PDCoV-N1 and PDCoV-N2 with anti-PEDV sera were analyzed after the recombinant proteins were analyzed by SDS-PAGE and purified by the Ni-NTA Superflow Cartridge. Meanwhile, Western blotting and indirect immunofluorescence assay were carried out separately to validate the recombinant proteins PDCoV-N1 and PDCoV-N2. Finally, we established an indirect ELISA method based on the recombinant protein PDCoV-N2 after optimizing the conditions and tested the sensitivity, specificity, and reproducibility of the method. Then, the established method was employed to examine 102 clinical serum samples. The recombinant protein PDCoV-N2 showed low cross-reactivity with anti-PEDV sera. The optimal conditions of the indirect ELISA method based on PDCoV-N2 were as follows: the antigen coating concentration of 1.25 μg/mL and coating at 37 ℃ for 1 h; blocking by BSA overnight at 4 ℃; serum sample dilution at 1:50 and incubation at 37 ℃ for 1 h; secondary antibody dilution at 1:80 000 and incubation at 37 ℃ for 1 h; color development with TMB chromogenic solution at 37 ℃ for 10 min. The S/P value ≥ 0.45, ≤0.38, and between 0.45 and 0.38 indicated that the test sample was positive, negative, and suspicious, respectively. The testing results of the antisera against porcine epidemic diarrhea virus (PEDV), porcine circovirus 2 (PCV2), transmissible gastroenteritis virus (TGEV), foot-and-mouth disease virus (FMDV), and African swine fever virus (ASFV) showed that the S/P values were all less than 0.38. The testing results of the 800-fold diluted anti-PDCoV sera were still positive. The results of the inter- and intra-batch tests showed that the coefficients of variation of this method were less than 10%. Clinical serum sample test results showed the coincidence rate between this method and neutralization test was 94.12%. In this study, an ELISA method for the detection of anti-PDCoV antibodies was successfully established based on the truncated N protein of PDCoV. This method is sensitive, specific, stable, and reproducible, serving as a new method for the clinical diagnosis of PDCoV.
Animals
;
Enzyme-Linked Immunosorbent Assay/methods*
;
Swine
;
Antibodies, Viral/blood*
;
Recombinant Proteins/genetics*
;
Deltacoronavirus/isolation & purification*
;
Coronavirus Infections/virology*
;
Swine Diseases/diagnosis*
;
Coronavirus Nucleocapsid Proteins
;
Sensitivity and Specificity
2.Construction of IgG4 Fc variants and their serum half-lives.
Xun GUO ; Huijun XIE ; Yuan ZHANG
Chinese Journal of Biotechnology 2025;41(8):3143-3154
In this study, we constructed a series of recombinant Fc variants of immunoglobulin G4 (IgG4), screened the fragment crystallizable (Fc) variants with significantly prolonged serum half-lives, and analyzed the relationship between mutation site and half-life, aiming to provide a theoretical basis for the development of IgG4 antibodies and Fc fusion protein-based drugs. Nine gene sites were selected for mutation, and different mutation sites were combined. The variant expression plasmids pET24b-Fc were constructed by molecular cloning and point mutation. The plasmids were transformed into Escherichia coli BL21(DE3) for the expression of different recombinant proteins of Fc. Fc2 and Fc3 variants had slightly lower recombinant protein yields, and the expression of other variants was not affected. The toxicity of different Fc variants was determined by cell counting kit-8 (CCK-8) and calcein acetoxymethyl ester/ propidium iodide (calcein AM/PI) in vitro and enzyme-linked immuno sorbent assay (ELISA) in vivo. The results showed that the recombinant Fc variants had good biocompatibility and safety. Finally, the Fc variants were labeled with fluorescent markers, and the effects of different mutations on their serum half-lives were investigated by in vivo experiments. The Fc5 variant with prolonged serum half-life was successfully screened out, which provided a theoretical and practical basis for the optimal design of IgG4 subtype antibody and Fc fusion protein drugs.
Immunoglobulin G/blood*
;
Immunoglobulin Fc Fragments/biosynthesis*
;
Half-Life
;
Animals
;
Escherichia coli/metabolism*
;
Humans
;
Recombinant Fusion Proteins/biosynthesis*
;
Recombinant Proteins/biosynthesis*
;
Mice
3.Why anticoagulant studies on sepsis fail frequently --- start with SCARLET.
Chinese Journal of Traumatology 2023;26(5):297-302
The Sepsis Coagulopathy Asahi Recombinant LE Thrombomodulin (SCARLET) trial has many defects, and thus cannot be the terminator of recombinant thrombomodulin (rTM). On the contrary, it provides sufficient evidence for further research. Based on analysis focusing on the failure of SCARLET and several previous anticoagulant studies, it is most important for new studies to grasp the following two points: (1) The enrolled cases should have sufficient disease severity and a clear standard for disseminated intravascular coagulation; (2) Heparin should not be used in combination with the investigated drugs. Multiple post-hoc analyses show that no combination of heparin will not increase the risk of thromboembolism. In fact, the combination of heparin can mask the true efficacy of the investigated drug. Due to the complexity of sepsis treatment and the limitations of clinical studies, the results of all treatment studies should be repeatedly verified, rather than be determined at one stroke. Some research conclusions contrary to disease physiology, pharmacology and clinical practice may be deceptive, and should be cautious rather than be simply accepted. On the other hand, the dissenting voices in the "consensus" scene are often well discussed by the authors and should be highly valued.
Humans
;
Anticoagulants/therapeutic use*
;
Thrombomodulin/therapeutic use*
;
Blood Coagulation Disorders
;
Disseminated Intravascular Coagulation/drug therapy*
;
Sepsis/drug therapy*
;
Heparin/therapeutic use*
;
Recombinant Proteins
4.Pharmacokinetics of Recombinant Human Coagulation Factor Ⅷ Preparations in Patients with Severe Hemophilia A.
Chuan-Ming LIN ; Zou-Fang HUANG ; Liu-Yan XIN ; Lin LI ; Xiang YANG ; Ting LI ; Yi-Jian CHEN
Journal of Experimental Hematology 2023;31(6):1787-1790
OBJECTIVE:
To calculate the pharmacokinetic parameters of recombinant human coagulation factor Ⅷ using myPKFiT in patients with severe hemophilia A, and provide an individualized treatment plan for patients.
METHODS:
A total of 42 patients with severe hemophilia A who were treated with recombinant human coagulation factor Ⅷ were included from January 2021 to December 2021. myPKFiT was used to calculate the pharmacokinetic parameters of FⅧ, and the individualized treatment plan for hemophilia A patients was formulated.
RESULTS:
The median age of 42 patients with severe hemophilia A was 31(16-50) years old, the average weight was 54.0±9.9 kg, the half-life of FⅧ was 12.05±1.6 h, the time to more than 1% of the baseline was 62.3±15.3 h, and the 0 bleeding rate after the guidance of myPKFiT was significantly increased from 39% to 49%, the Annual bleeding rate was reduced from 3.6±2.5 to 2.1±2.0, and the Annual joint bleeding rate was reduced from 3.2±2.2 to 1.9±0.9, all of which were statistically different (P<0.05).
CONCLUSION
Individualized therapy in patients with severe hemophilia A who were guided by myPKFiT assay of pharmacokinetics parameters can significantly reduce the annual bleeding rate and annual joint bleeding rate of patients.
Adult
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Humans
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Middle Aged
;
Blood Coagulation Factors
;
Factor VIII/pharmacokinetics*
;
Hemophilia A
;
Hemorrhage
;
Recombinant Proteins/pharmacokinetics*
;
Adolescent
;
Young Adult
5.Effect of Recombinant Human Thrombopoietin (rhTPO) on Long-term Hematopoietic Recovery in Mice with Acute Radiation Sickness and Relative Mechanism.
Hao LUAN ; Shuang XING ; Jing-Kun YANG ; Ye-Mei WANG ; Xue-Wen ZHANG ; Zi-Zhi QIAO ; Xing SHEN ; Zu-Yin YU
Journal of Experimental Hematology 2023;31(2):546-552
OBJECTIVE:
To investigate the effect and relative mechanism of Recombinant Human Thrombopoietin (rhTPO) on long-term hematopoietic recovery in mice with acute radiation sickness.
METHODS:
Mice were intramuscularly injected with rhTPO (100 μg/kg) 2 hours after total body irradiation with 60Co γ-rays (6.5 Gy). Moreover, six months after irradiation, peripheral blood, hematopoietic stem cells (HSC) ratio, competitive transplantation survival rate and chimerization rate, senescence rate of c-kit+ HSC, and p16 and p38 mRNA expression of c-kit+ HSC were detected.
RESULTS:
Six months after 6.5 Gy γ-ray irradiation, there were no differences in peripheral blood white blood cells, red blood cells, platelets, neutrophils and bone marrow nucleated cells in normal group, irradiated group and rhTPO group (P>0.05). The proportion of hematopoietic stem cells and multipotent progenitor cells in mice of irradiated group was significantly decreased after irradiation (P<0.05), but there was no significant changes in rhTPO group (P>0.05). The counts of CFU-MK and BFU-E in irradiated group were significantly lower than that in normal group, and rhTPO group was higher than that of the irradiated group(P<0.05). The 70 day survival rate of recipient mice in normal group and rhTPO group was 100%, and all mice died in irradiation group. The senescence positive rates of c-kit+ HSC in normal group, irradiation group and rhTPO group were 6.11%, 9.54% and 6.01%, respectively (P<0.01). Compared with the normal group, the p16 and p38 mRNA expression of c-kit+ HSC in the irradiated mice were significantly increased (P<0.01), and it was markedly decreased after rhTPO administration (P<0.01).
CONCLUSION
The hematopoietic function of mice is still decreased 6 months after 6.5 Gy γ-ray irradiation, suggesting that there may be long-term damage. High-dose administration of rhTPO in the treatment of acute radiation sickness can reduce the senescence of HSC through p38-p16 pathway and improve the long-term damage of hematopoietic function in mice with acute radiation sickness.
Humans
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Mice
;
Animals
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Thrombopoietin/metabolism*
;
Hematopoietic Stem Cells
;
Blood Platelets
;
Recombinant Proteins/therapeutic use*
;
Radiation Injuries
;
RNA, Messenger/metabolism*
6.Effect of artificial liver with double plasma molecular absorb system model on patients' platelets and corresponding treatment strategy.
Jin Feng JIA ; Fei LIANG ; Jian Wei HUANG ; Hao WANG ; Pu Qing HAN
Journal of Peking University(Health Sciences) 2022;54(3):548-551
OBJECTIVE:
To compare the effects of artificial liver treatment with double plasma molecular adsorption system(DPMAS) mode and traditional plasma exchange (PE) mode on platelets in patients, and to evaluate the clinical efficacy of recombinent human thrombopoietin (rhTPO) in the treatment of thrombocytopenia.
METHODS:
A total of fifteen patients undergoing artificial liver with DPMAS model admitted to the Fifth Affiliated Hospital of Guangzhou Medical University from January 2018 to November 2020 were selected and included in the DPMAS group, and another 15 patients receiving PE were selected and included in the PE group. The improvement of clinical symptoms, such as fatigue, jaundice, oliguria, edema, etc. before and after artificial liver treatment was compared between the two groups, and the trend of blood routine (especially platelet), coagulation function and other indexes before and after treatment were compared between the two groups. The use of rhTPO and the number of platelets were recorded during treatment.
RESULTS:
The improvement rate of clinical symptoms in DPMAS group was 86.67%, which was higher than that in PE group, but the difference was not statistically significant (P>0.05). There was no statistical significance in the outcome of the two groups within 90 days (P>0.05). There was no significant difference in white blood cell (WBC) and hemoglobin (HB) between the two groups after treatment (P>0.05). However, the level of platelet(PLT) in DPMAS group was significantly lower than that before treatment (P < 0.05), and was significantly lower than that in PE group (P < 0.05). After treatment, the international normalized ratio (INR) level in PE group was significantly improved (P < 0.05), but there was no significant difference in the INR level in DPMAS group (P>0.05). The patients in the DPMAS group received an average of (8.2±3.1) doses of rhTPO and (1.5±0.3) IU of platelet transfusions during hospitalization. In DMPAS group, platelets increased significantly after infusion of terbium.
CONCLUSION
Compared with PE mode, the artificial liver with DPMAS mode can reduce platelet levels in patients, but the application of rhTPO can stimulate platelet regeneration and increase platelet levels in the patients, thereby reducing the risk of bleeding due to platelet hypoplasia.
Blood Platelets
;
Humans
;
Liver, Artificial
;
Plasma Exchange
;
Recombinant Proteins
;
Thrombocytopenia/therapy*
;
Thrombopoietin
7.Expression, purification and bioactivity analysis of a recombinant fusion protein rHSA-hFGF21 in Pichia pastoris.
Tiantian HUANG ; Jianying QI ; Ganggang YANG ; Xianlong YE
Chinese Journal of Biotechnology 2022;38(9):3419-3432
Human fibroblast growth factor 21 (hFGF21) has become a candidate drug for regulating blood glucose and lipid metabolism. The poor stability and short half-life of hFGF21 resulted in low target tissue availability, which hampers its clinical application. In this study, the hFGF21 was fused with a recombinant human serum albumin (HSA), and the resulted fusion protein rHSA-hFGF21 was expressed in Pichia pastoris. After codon optimization, the recombinant gene fragment rHSA-hFGF21 was inserted into two different vectors (pPIC9k and pPICZαA) and transformed into three different strains (X33, GS115 and SMD1168), respectively. We investigated the rHSA-hFGF21 expression levels in three different strains and screened an engineered strain X33-pPIC9K-rHSA-hFGF21 with the highest expression level. To improve the production efficiency of rHSA-hFGF21, we optimized the shake flask fermentation conditions, such as the OD value, methanol concentration and induction time. After purification by hollow fiber membrane separation, Blue affinity chromatography and Q ion exchange chromatography, the purity of the rHSA-hFGF21 protein obtained was 98.18%. Compared to hFGF21, the biostabilities of rHSA-hFGF21, including their resistance to temperature and trypsinization were significantly enhanced, and its plasma half-life was extended by about 27.6 times. Moreover, the fusion protein rHSA-hFGF21 at medium and high concentration showed a better ability to promote glucose uptake after 24 h of stimulation in vitro. In vivo animal studies showed that rHSA-hFGF21 exhibited a better long-term hypoglycemic effect than hFGF21 in type 2 diabetic mice. Our results demonstrated a small-scale production of rHSA-hFGF21, which is important for large-scale production and clinical application in the future.
Animals
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Blood Glucose/metabolism*
;
Diabetes Mellitus, Experimental
;
Fibroblast Growth Factors
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Humans
;
Hypoglycemic Agents/metabolism*
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Methanol/metabolism*
;
Mice
;
Pichia/metabolism*
;
Recombinant Fusion Proteins
;
Recombinant Proteins/metabolism*
;
Saccharomycetales
;
Serum Albumin/metabolism*
;
Serum Albumin, Human/metabolism*
8.Changes in the Cytokine Profiles of Patients with Chronic Hepatitis B during Antiviral Therapy.
Ming Hui LI ; Hui Hui LU ; Qi Qi CHEN ; Yan Jie LIN ; Zhan ZENG ; Yao LU ; Lu ZHANG ; Jian Ping DONG ; Wei YI ; Yao XIE
Biomedical and Environmental Sciences 2021;34(6):443-453
Objective:
To investigate the changes in the cytokine profiles of chronic hepatitis B (CHB) patients undergoing antiviral treatment.
Methods:
Hepatitis B e antigen (HBeAg)-positive patients were treated with Pegylated interferon (PEG-IFN) and entecavir (ETV). Clinical biochemistry and cytokines were detected at baseline and every 3 months.
Results:
In all, 200 patients completed 48 weeks of treatment, 100 in the PEG-IFN group and 100 in the ETV group. During 3-6 months of treatment, compared with baseline, the PEG-IFN group showed a significant decrease in interferon-gamma (IFN-γ), interleukin-17A (IL-17A), interleukin-6(IL-6), interleukin-10(IL-10), and transforming growth factor beta (TGF-β) (
Conclusion
During antiviral therapy, a change in the cytokine profile occurred; in the aspect of immune control and functional cure, PEG-IFN was significantly better than ETV.
Adult
;
Antiviral Agents/therapeutic use*
;
Cytokines/blood*
;
Female
;
Guanine/therapeutic use*
;
Hepatitis B, Chronic/drug therapy*
;
Humans
;
Interferon-alpha/therapeutic use*
;
Male
;
Polyethylene Glycols/therapeutic use*
;
Prospective Studies
;
Recombinant Proteins/therapeutic use*
9.Effect of modified Buyang Huanwu Decoction on hemorrhagic transformation after rt-PA intravenous thrombolysis in patients with super early cerebral infarction.
Yong-Kun LU ; Hai-Yan YANG ; Xiang-Zhe LIU ; Yan-Hua WANG ; Jun-Hong YANG
China Journal of Chinese Materia Medica 2019;44(8):1696-1703
To study the effect of modified Buyang Huanwu Decoction on the hemorrhagic transformation after intravenous thrombolysis of recombinant tissue type plasminogen activator(rt-PA) in patients with super early(onset time<4. 5 h) cerebral infarction. From March 2016 to July 2018,at the brain disease zone of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine,212 cases of super early cerebral infarction were selected and divided into two group according to the randomized complete blocks designs: control group(106 cases) and traditional Chinese medicine group(106 cases). The control group was treated with rt-PA intravenous thrombolysis,while the traditional Chinese medicine group was treated with modified Buyang Huanwu Decoction in addition to the therapy of the control group. Both groups were treated for 14 days. Neurological deficit score,serum matrix metalloproteinase-9(MMP-9),neuron specific enolase(NSE),vascular endothelial growth factor(VEGF) and plasma cellular fibronectin(c-FN) levels,the incidence of hemorrhagic transformation,clinical efficacy and adverse drug reactions before and after treatment were compared between the two groups. According to the findings,at the 14 thday after treatment,the rank sum test of the grade data showed that the clinical efficacy of the traditional Chinese medicine group was better than that of the control group(Z =-2. 033,P = 0. 042); on the basis of χ2 test,the total efficiency of the traditional Chinese medicine group was higher than that of the control group(χ2= 4. 895,P =0. 027); the hemorrhagic transformation rate of the traditional Chinese medicine group was lower than that of the control group within14 days of treatment(χ2= 3. 962,P = 0. 047). MMP-9 levels in the traditional Chinese medicine group were lower than those in the control group at the 3 rd,5 th,7 th,10 th,14 thd after treatment(t =-2. 474,-3. 022,-5. 163,-6. 998,-9. 821; P = 0. 014,0. 003,0,0,0). The improvement of c-FN,NSE,VEGF and NIHSS scores in the traditional Chinese medicine group was superior to that of the control group after 14 days of treatment(t =-2. 343,-3. 187,-2. 129,-3. 105; P = 0. 020,0. 002,0. 034,0. 002). No obvious adverse reactions of modified Buyang Huanwu Decoction were observed during 14 days of treatment. Modified Buyang Huanwu Decoction could reduce the expressions of MMP-9,c-FN,NSE and VEGF after rt-PA intravenous thrombolysis in patients with super early cerebral infarction,and decrease the hemorrhagic transformation rate after thrombolysis,with high safety.
Cerebral Infarction
;
drug therapy
;
Drugs, Chinese Herbal
;
therapeutic use
;
Fibronectins
;
blood
;
Humans
;
Matrix Metalloproteinase 9
;
blood
;
Medicine, Chinese Traditional
;
Phosphopyruvate Hydratase
;
blood
;
Recombinant Proteins
;
therapeutic use
;
Thrombolytic Therapy
;
Tissue Plasminogen Activator
;
therapeutic use
;
Vascular Endothelial Growth Factor A
;
blood
10.Effect of recombinant human thrombopoietin on endotoxin-induced thrombocytopenia in mice.
Jiawei JIANG ; Bing WANG ; Xin YU ; Hua XU ; Yongqiang WANG
Chinese Critical Care Medicine 2019;31(9):1108-1112
OBJECTIVE:
To investigate the effect of recombinant human thrombopoietin (rhTPO) on thrombocytopenia (TCP) induced by endotoxin lipopolysaccharide (LPS) in mice.
METHODS:
Sixty male C57BL/6 mice were divided into normal saline (NS) control group (NS group), sepsis-induced TCP model group (LPS group) and rhTPO treatment group (LPS+rhTPO group) by random number table with 20 mice in each group. Sepsis-induced TCP model was reproduced by one intraperitoneal injection of LPS 30 mg/kg, and the mice in NS group were given the same amount of NS. In LPS+rhTPO group, 2.7 kU/kg rhTPO was subcutaneously injected into mice immediately after intraperitoneal injection of LPS, once every 24 hours. The mice in NS group and LPS group were injected subcutaneously with the same amount of NS. The observation period of each group lasted for 72 hours. The inner canthus blood was harvested before and every 24 hours after modeling, and the platelet count (PLT) was measured by animal blood cell counter. The eyeball blood of mice was harvested at 72 hours after modeling, and the proportion of CD61+CD62p+ cells in platelet-rich plasma was detected by flow cytometry, by which the platelet activation was reflected. Lung and spleen tissues of mice were harvested, and the positive expression of CD41 was determined by immunohistochemistry, by which the platelet sequestration in organs was reflected. Bone marrow cells from unilateral femur of mice were harvested, and the proportion of CD41+CD61+ cells was determined by flow cytometry to reflect the proliferation of bone marrow megakaryocytes.
RESULTS:
There was no significant difference in PLT among the groups before modeling. With the extension of the time after modeling, PLT in LPS group was decreased continuously, and increased slightly at 72 hours, but it was still significantly lower than that in NS group (×109/L: 308.60±21.70 vs. 1 152.72±50.27, P < 0.05); PLT in LPS+rhTPO group was increased continuously with the extension of modeling time, and it was significantly higher at 72 hours than that in LPS group (×109/L: 926.78±48.85 vs. 308.60±21.70, P < 0.05). At 72 hours after modeling, the proportion of CD61+CD62p+ cells in platelet-rich plasma of LPS group was significantly higher than that of NS group [(25.07±2.55)% vs. (4.17±0.38)%, P < 0.05], while the value in LPS+rhTPO group was significantly lower than that of LPS group [(15.92±1.26)% vs. (25.07±2.55)%, P < 0.05]. The proportion of CD41+CD61+ cells in bone marrow megakaryocytes of LPS group was significantly higher than that of NS group [(11.84±0.80)% vs. (3.60±0.42)%, P < 0.05], and the proportion of CD41+CD61+ cells in LPS+rhTPO group was significantly higher than that in LPS group [(30.96±2.49)% vs. (11.84±0.80)%, P < 0.05]. Immunohistochemistry showed that the positive expressions of CD41 in lung and spleen tissues of LPS group increased significantly than NS group [A value: 828.94±119.30 vs. 447.09±16.19 in lung tissue, (280.15±16.71)×103 vs. (0.65±0.26)×103 in spleen tissue, both P < 0.05], while the positive expressions of CD41 in lung and spleen tissues of LPS+rhTPO group decreased significantly than LPS group [A value: 542.78±2.95 vs. 828.94±119.30 in lung tissue, (129.40±13.49)×103 vs. (280.15±16.71)×103 in spleen tissue, both P < 0.05].
CONCLUSIONS
The rhTPO in endotoxin-induced TCP may stimulate the proliferation of bone marrow megakaryocytes, inhibit platelet activation and affect platelet sequestration in organs, so as to increase platelet levels.
Animals
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Blood Platelets
;
Humans
;
Male
;
Mice
;
Mice, Inbred C57BL
;
Platelet Count
;
Recombinant Proteins
;
Thrombocytopenia
;
Thrombopoietin

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