Construction of a rapid depression screening model for blood donors in Guangzhou based on decision tree / 中国输血杂志

【Objective】 To investigate the prevalence of depression in blood donors and analyze the related factors, so as to develop a rapid depression screening model for blood donors. 【Methods】 A total of 13 015 street whole blood donors in Guangzhou Blood Center during May to August, 2020 filled in an anonymous e-questionnaire, including social demography information and the Patient Health Questionnaire-9 before donation. The cut-off value for detecting depression was 10. Logistic regression by SPSS 26.0 was used to analyze depression related factors. 2-level decision tree with 30/10 as the minimum number of cases in parent/child node, 10-fold cross validation was used to cut items of PHQ-9 to form the depression screening model. 【Results】 364 out of 13 015 (2.80%) street whole blood donors reported a score ≥ 10. Donors with 18-29 years old (P <0.05), unmarried (P<0.05), less than 50 000 RMB household income per year (P< 0.05) were more prone to depression. 81.96% donors in "<10 scores" group, while 3.85%donors in "≥ 10 scores" group were in two terminal nodes formed by Item-6, 2 and 4 of PHQ-9. After verification by the 10 fold crossover method, the estimated misclassification risk of the model was 1.7%. 【Conclusion】 The screening prevalence of depression based on PHQ-9 in Guangzhou blood donors was 2.8%(95% CI: 2.52%-3.09%) . Donation frequency was not related to depression. A rapid and efficient depression screening model for blood donors based on item-6, 2 and 4 of PHQ-9 was developed.

The development of a screening model for type 2 diabetes mellitus in community population of Xinjiang Karamay / 中华内分泌代谢杂志

Objective:To develop a nomogram model for screening of type 2 diabetes mellitus in a community population.Methods:From October to December, 2020, 6 028 community residents who participated in the " national health physical examination" in Karamay community with complete physical examination data and met the inclusion and exclusion criteria were selected. The physical examination data included medical history, physical examination, laboratory, and ultrasound reports. Random segmentation sampling was used to divide the population into modeling and validation cohorts, and LASSO regression analysis was used to screen for independent factors associated with diabetes diagnosis. The independent influencing factors were furthor incorporated into the multi-factor logistic regression, and the RMS software package was used to construct the column chart. The area under receiver operating characteristic(ROC) curve was used to measure the differentiation of the model. The calibration curve can directly reflect the calibration degree of the model.Results:In the modeling group, multivariate logistic regression analysis showed that age, gender(female), history of hypertension, history of hyperlipidemia, HbA 1C, urinary microalbumin, homeostasis model assessment for insulin resistance, and triglycerides and glucose index were independently associated with diabetes. OR were 1.053(95% CI 1.038-1.069), 0.681(95% CI 0.512-0.906), 1.802(95% CI 1.227-2.626), 1.789(95% CI 1.303-2.448), 10.973(95% CI 8.318-14.745), 1.002(95% CI 1.001-1.004), 2.914(95% CI 2.248-3.799), and 2.673(95% CI 2.03-3.536), respectively. The areas under ROC curves of the training set and the validation set were 0.945 and 0.955, respectively. The optimal critical value in the ROC curve was 0.178(sensitivity 0.930, specificity 0.839) in the training set and 0.201(sensitivity 0.945, specificity 0.848) in the validation set. Conclusion:The screening model of type 2 diabetes developed in this study has good accuracy, which can be used as a screening tool for high-risk population of type 2 diabetes.

Establishment and application of STING agonist in-vitro screening model / 药学学报

Tumor immunotherapy is a critical field in the development of anticancer drugs. The research of stimulator of interferon genes (STING) agonist provides a new idea for immunotherapy. Innate immune response can effectively be induced by nucleic acids in mammalian cytoplasm. In recent years, a large number of studies have confirmed that the cGAS-cGAMP-STING signaling pathway plays a key role in cytoplasmic DNA recognition and immune defense activation. The dysfunction of cGAS-cGAMP-STING is closely related to the tumorigenesis, and is a potent target for drug development. In this study, based on THP-1 dual cells which are stably expressing cGAS-STING pathway and THP-1 KO-STING cells which are stably depleted STING, a screening method for STING agonists was established by detection of luciferase. Furthermore, the accuracy and sensitivity of the model were verified using positive compound, providing a simple, efficient and accurate screening platform for high-throughput screening of STING agonists.

The optimization and application of cell-based screening model for IL-17-mediated signaling pathway / 药学学报

We explore and verify the optimized condition for HEK-Blue IL-17 screening model, and screen the compounds that inhibits IL-17-medited signaling pathway. HEK-Blue IL-17 cells (5×104 cells per well) were seeded into the 96 plates followed by different concentrations of IL-17A or IL-17F alone, or in combination with tested compounds for 16 h. Then, the supernatant medium was incubated with QUANTI-Blue for 1 or 3 h to detect the OD value at λ655nm. The secreted alkaline phosphatase (SEAP) production was an index of IL-17-mediated signaling activation in HEK-Blue IL-17 cells. We found that both IL-17A and IL-17F can significantly activate the IL-17 signaling pathway in HEK-Blue IL-17 cells. The available dosage of IL-17A and IL-17F were 10 and 100 ng·mL-1, respectively. The reaction time of SEAP and QUANTI-Blue was 1 h. In this model, arctigenin and epigallocatechin gallate (EGCG) could inhibit the IL-17A and IL-17F-mediated signaling pathway. This established and optimized screening model of HEK-Blue IL-17 cells was suitable for screening inhibitors of IL-17-mediated signaling pathway.

Establishment of a screening model for compounds uncoupling the interaction of nNOS with PSD-95 / 药学学报

In ischemic stroke, increased level of neuronal complex of nitric oxide synthase (nNOS)-postsynaptic density protein-95 (PSD-95) plays an important role in neuronal damage. We aimed to establish a screening model to identify compounds capable of uncoupling nNOS interaction with PSD-95. In this model, human embryonic kidney-293T (HEK-293T) cells were transfected with either pCDH-Flag-nNOS or pcDNA3.1-PSD-95 plasmid to obtain the protein of Flag-nNOS or PSD-95. Incubating Flag-nNOS with PSD-95 causes formation of the nNOS-PSD-95 complex. ZL006, a known uncoupler of nNOS-PSD-95 interaction, can disturb the interaction between Flag-nNOS and PSD-95, serving as a positive control. The method coupling antibodies to magnetic beads with glutaraldehyde was used to decrease the cost and increase the efficiency. To establish that our model is suitable for selecting nNOS-PSD-95 uncouplers, we evaluated the ability of IC87201, another reported uncoupler of nNOS-PSD-95 interaction, and structural analogs of ZL006. IC87201 and one structure analog of ZL006 showed uncoupling effect, supporting that our model can be used to select different types uncoupler blocking nNOS-PSD-95 interaction.

Validation of NoSAS Score and Obstructive Sleep Apnea Hypopnea Syndrome Screening Model for Female Snorers in Females with Obstructive Sleep Apnea / 中国医学科学院学报

To evaluate the NoSAS score and the obstructive sleep apnea hypopnea syndrome(OSAHS)screening model for female snorers with obstructive sleep apnea(OSA)in females and compare the performance of these two tools. A total of 425 females with suspected OSA who underwent overnight polysomnography(PSG)were consecutively recruited into this study.The above two questionnaires were completed.Based on the severity of OSA which was determined by apnea-hypopnea index(AHI),the patients were classified into four groups:non-OSA group(AHI15 events/h),and severe OSA group(AHI>30 events/h).The sensitivity,specificity,positive predictive values,negative predictive values,and the area under the receiver operating characteristics(ROC)curve of two questionnaires were calculated. The sensitivity of NoSAS score for OSA,moderate-to-severe OSA,and severe OSA groups were 57.3%,64.9%,and 69.5%,and its specificity was 83.5%,76.6%,and 70.9%,respectively.The sensitivity of the OSAHS screening model of female snorers was 62.7%,74.8%,and 75.8%,and its specificity was 92.5%,84.3%,and 74.5%,respectively.Both of these two screening tools had high specificity and performed well in ruling out non-OSA females.For patients with their AHI≥5 events/h,the results of NoSAS score and OSAHS screening model were in moderate to high consistency with those diagnosed by PSG,with a Kappa value of 0.401 and 0.541,respectively.The area under curve of these two tools was 0.792(95% =0.750-0.829)and 0.866(95% =0.830-0.897),respectively,showing moderate screening value.The area under curve of the OSAHS screening model of female snorers was significantly larger than that of NoSAS score( =0.002, =0.003, =0.019). Both the NoSAS score and the OSAHS screening model for female snorers have a moderate performance in diagnosing OSA in females,although the OSAHS screening model for female snorers has better performance.However,the sensitivity of the OSAHS screening model needs to be further improved.

Establishment and application of a drug screening model targeting somatostatin receptor 2 / 中国药理学通报

Aim To establish a cell model to detect the activity of somatostatin (SST) by targeting somatostatin receptor 2 (SSTR2), and to provide a simple and stable evaluation method for the drug screening of SSTR2 agonists and somatostatin analogues (SSTA). Methods The target gene of SSTR2 was integrated into the pEGFP-N3 vector, and the recombinant plasmid was constructed and transfected into HEK293 cells. After G418 screening, positive clone was selected and the stable cell lines were obtained by expanding culture. The stable cell lines were identified by fluorescence cell imaging, Western blot and qPCR. A calcium flow detection system was established to optimize cell number, fluorescence dye concentration and incubation time. Finally, the screening model was used to detect the different batches of the marketed somatostatin preparation Stilamin. Results SSTR2 stable cell lines were successfully constructed, and the receptors were mainly distributed on the cell membrane. The optimal conditions for calcium flow detection were determined as follows; 30 000 cells/Well, Fluo-4/AM indicator concentration was 3 p,mol • L -1 ~5 u,mol • L-1 , incubation time was 45 min. Under this condition, EC50 value of Stilamin in different batches was stable. Conclusions SSTR2 overexpressed stable cell lines are successfully constructed and calcium flow detection method is optimized to provide a simple and stable model for the screening of somatostatin receptor agonists.

Antidepressant Effect of Methanol Fruit Extract of Capsicum annuum in Mice

Aims: To determine the antidepressant potential of methanol fruit extract of Capsicum annuum in Mice. Methodology: Force Swim Test (FST), Tail Suspension Test (TST) and Open Field Test (OFT) were used. Immobility time in both FST and TST was determined by randomly dividing 30 mice into five (5) groups of six (6) mice each. Group 1 received saline, Group 2, Imipramine (15 mg/kg), Group 3, 4, and five were treated with 500 mg/kg, 1000 mg/kg, and 2000 mg/kg of methanol extract of fruits of Capsicum annuum respectively. In the OFT, 25 mice were divided into five(5) groups of five (5) mice each; Group 1 received normal saline, group 2, Diazepam (0.5 mg/kg), group 3,4 and 5 were treated with 500 mg/kg, 1000 mg/kg and 2000 mg/kg of methanol fruit extract of C. annuum respectively. Results: Imipramine, and the doses of the methanol fruit extract significantly reduced the immobility time when compared with a normal saline group (p≤ 0.05) in the mice FST and TST. The effect of the extract was dose-dependent; 2000 mg/kg produced the highest reduction. In the Open field test (OFT), the number of square crossing showed no significant difference between Diazepam (0.5 mg/kg) and all the doses of the extract administered. This implied that the extract did not act as a stimulant. Conclusion: The decrease behavioural despair in this study suggests that Capsicum annuum may be a promising candidate for the management of depression. The antidepressant like activity may be attributed to the presence of anti-inflammatory and antioxidant flavonoids and triterpene in the plants given the role of inflammation and oxidative stress in depression. Further work will be carried out to validate this result.

Validation and application a cell-based screening model for IL-6/JAK/STAT3 inhibitor / 药学学报

Interleukin-6 (IL-6)/janus kinase (JAK)/signal transducers and activators of transcription 3 (STAT3) is a pivotal signaling pathway in the regulation of cell proliferation, survival, differentiation and T cell activation. Aberration of this pathway is involved in multiple autoimmunity diseases and cancers, therefore the pathway is considered as a hot target for drug development. In our study, we validated a cell-based model of IL-6/JAK/STAT3 and used it in screening of its inhibitors. HEK-Blue IL-6 cells of Invivogen Inc. were used to stably express IL-6 receptor and STAT3-induced secreted embryonic alkaline phosphatase (SEAP) report gene. After stimulation by IL-6, SEAP was secreted from cells and reacted with QUANTI-Blue. The product can be detected at 655 nm. The inhibitory effect of compounds on STAT3 signaling showed as IC50 was calculated by OD value. The results shown that IL-6 specifically activated the cells, which could be applied to screen the inhibitors for IL-6/JAK/STAT3 signaling pathway. The optimized screening conditions were described as below:50 000 cells/well, 1 ng·mL-1 IL-6 incubation for 20 h and reaction with QUANTI-Blue for 1 h. Based on this condition, we screened 14 natural products based on this cell model and arctigenin, cryptotanshinone and curcumin showed potential inhibitory activities on STAT3 signaling pathway with IC50 of 1.28, 2.96 and 6.61 μmol·L-1. Our study suggests that HEK-Blue IL-6 cells were suitable for screening inhibitors for the IL-6/JAK/STAT3 signaling pathway.

Drug screening model of treating pigmentation disorders in tyrp1a transgenic zebrafish / 中国药科大学学报

@#To effectively screen treating pigmentation disorders drug, a new transgenic zebrafish drug screening model was constructed. Green fluorescent protein(GFP)were drived by tyrosinase-related protein 1a (tyrp1a)promoter specific expression in melanocyte. Effect of N-Phenylthiourea(PTU)and alpha-melanaocyte stimulating hormone(α-MSH)on the GFP expression and melanogenic of tyrp1a: eGFP zebrafish were photographed under the steromicroscope. Results showed that PTU could significantly inhibit the melanogenic and expression of GFP of zebrafish. As compared with control group, α-MSH treatment resulted in marked stimulation of body pigmentation and expression of GFP. In conclusion, a new transgenic zebrafish drug screening model was successfully established, which can be used for treating pigmentation disorders.

The cell model establishment through lentivirus transfecting fluorescent protein EYFP-H148Q/I152L / 西安交通大学学报(医学版)

Objective To establish the HeLa cell line that can stably express EYFP fluorescent protein as the model for anion channel blocker (halide ion) screening ,which lays the foundation for high throughput screening of anion channel blocker (halide ion) .Methods Through gene recombination technology ,a new lentivirus vector which can express mutant protein YFP (EYFP‐H148Q/I152L) and puromycin resistance ,was built .The mixture of lentivirus vector and packaging plasmid was transfected into 293T cells to produce lentivirus particles . After infection of HeLa cells by the lentivirus particles ,puromycin was used to screen the cells as YFP‐positive HeLa cell line .Then cell amplification was carried out after purification and efficiency of EYFP‐H148Q/I152L was further detected by Real‐time quantitative PCR (RT‐PCR) and Western blot .We then verified the activity of EYFP‐HeLa transfected cell line as a screening model of anion channel blocker .Results Gene sequencing verified that EYFP‐H148Q/I152L was successfully inserted into lentivirus vectors .RT‐PCR and Western blot results showed that the target gene was overexpressed in HeLa cells . The specific yellow fluorescence of EYFP of HeLa cells could be observed under fluorescence microscope with the efficiency of nearly 100% . I- (low permeability ) solution stimulated the opening of anion (halogen) channels ,and the yellow fluorescence was quenched by I - flow into cells . Conclusion The EYFP‐HeLa cell line can stably express EYFP yellow fluorescent protein and is sensitive to the internal flow of I - .Therefore ,it can be used as an ideal screening model of anion channel blocker (halide ion) .

Screening of natural compounds with neuronal differentiation promoting effects in a cell-based model / 中国天然药物

The purpose of this study was to establish a drug screening method for small molecules extracted from traditional Chinese medicines (TCM) that have neuronal differentiation promoting effects, using P19 embryonic carcinoma cell as a cell-based model. First, the constructed plasmid (pTα1-Luc) was transfected into P19 cells to establish a screening model. Second, several TCMs were screened using the established model and all-trans-retinoic acid as a positive control. Finally, the underlying molecular mechanism was explored using immunofluorescence staining, qT-PCR, and Western blot analysis. Our results indicated that the drug screen model was established successfully and that both honokiol and hyperoside induced P19 differentiation into neurons, with the possible molecular mechanism being modulating the Wnt signaling pathway. In conclusion, the drug screening model developed in the present study provides a rapid, cell-based screening platform for identifying natural compounds with neuronal differentiation effects.

Establishment of a novel high throughput screening assay for identifying small molecular antagonists of human interleukin-6 receptor / 军事医学

Objective To establish a high throughput screening assay for identifying human small molecular antagonists targeted IL-6R.Methods The full length gene of the human IL-6R extracellular region was amplified by PCR and cloned into a eukaryotic expression vector to construct recombination expression plasmid pABHis -IL6R that was then transfected transiently into HEK293T cells to prepare recombination protein IL-6R.Western blotting assay and receptor-ligand binding experiment were used to analyze the bioactivity of IL-6R.A new screening method based on ELISA was established using the function of IL-6R binding to its ligand and the characteristics of Fc fragment binding to IgG-HRP.Then Z′-factor was calculated and a known antagonist ab 47215 was used to assess the stability and reliability of the new assay .Results Recombination plasmid pABHis-IL6R was constructed and soluble IL-6R was prepared.IL-6R reported herein could be recognized by an anti-IL-6R antibody and specifically bind to its ligand in a dose response manner .A Z′-factor of 0.53 was obtained that could serve high throughput screening assay .Ab47215 , as a known specific antagonist , was able to block rhIL-6 from binding to the receptor in a dose-dependent manner in the new screening assay , the IC50 of which was (0.55 ± 0.11)μg/ml.Conclusion An innovative and easy screening assay for identifying human IL-6R antagonists is established , which might help discover potent and specific antagonists .

Establishment of high throughput screening model for anti-HIV drugs with p-TEFb as target and its application in screening Chinese meteria medica / 中草药

Objective: To establish a rapid high-throughput screening model with positvive transcription elongation factor (p-TEFb) as target for screening the inhibitors of HIV. Methods: Double cross plasmid of BD-Tat and AD-CyclinT1 was established and transformed into yeast AH109 and Y187, respectively. AH109/pGBKT7-Tat was mated with Y187/pGADT7-CyclinT1 and the diploids were subjected to autoactivation, toxicity test, and reporter gene assay. The screening model based on double hybrid system was established. Results: Two out of 20 kinds of Chinese materia medica possessing immunity-enhancing effects were identified as primary hits, the anti-HIV activity of these two positive drugs was already demonstrated by other researchers through detecting the suppression effects on HIV duplication in vitro. Conclusion: The system established in this paper can be used for rapid high-throughput screening anti-HIV chemicals or herbs. Further research for the obtained two positive Chinese materia medica, Cibotii Rhizoma and Coptidis Rhizom should be carried out to isolate the effective component for disrupting the interaction between HIV Tat and CyclinT1.

Optimization research on in vitro screening model for human leukocyte elastase inhibitor / 第二军医大学学报

Objeciive To explore the most suitable reaction condition for human leukocyte elastase (HLE) and its substrates, so as to establish a high-throuthput in vitro screercng model for HLE mhibiton Methods By measuring the UV absorbance of the product p-NA, we studied the dectrolyte concentration, temperature, pH, enzyme/substrate concentration, the influence of reaction time, and deteclion wavelength on the reaclion, so as to determine the optimal condilion for the reaclion between HLE and its substrates. Results The suitable reaction condition was determined as followes: HLE (0. 2 U/ml) 30 μl, substrates (50 mmol/L) 100 μl, Ttiis buffer (1.0 mol/L NaCl, pH 7. 5), temperatiire 37°C, reaction lime 24 h, and detection wavelength 545 nm. Conclution We have successfully established a stable in vitfo HLE inhibitor screening model with high sensitivity, accuracy, and repeatability, which provides a better platform for HLE inhibitor screening.

Cloning and Expression of EGFR Tyrosine Kinase and Construction of the Screening Model for the Enzymatic Inhibitors / 中国生物工程杂志

As a member of tyrosine kinases(TK) family,Epidermal growth factor receptor(EGFR) has an activity of intrinsic protein tyrosine kinase,which plays an essential role in the regulation of signal transduction in the cells.Due to the abnormal expression of EGFR-TK,the certain type cancers may developed and progressed.Based on that,the inhibitors of EGFR-TK could be effective medicines for the treatment of cancer.The EGFR-TK domain was amplified by RT-PCR with RNA of HUVCEs cells as the template and expressed in E.coliBL21(DE3) using plasmid pET30a as vector.The recombinant protein was purified with the affinity chromatography(Ni-NTA),which was identified to have kinase activity catalyzing the substrate phosphorylated with ATP in the enzymatic reaction.Using the recombinant EGFR-TK as target,the screening model for enzymatic inhibitors was constructed.

Study on microassay for screening ?-glucosidase inhibitors by orthogonal matrix method / 中国药理学通报

Aim To provide practical microassay for screening ?-glucosidase inhibitors in drug discovery.Methods The optimal conditions of assaying the activity of ?-glucosidase were determined in 96-well plates under physiological pH value and temperature by orthogonal matrix method.Reaction time and the concentrations of ?-glucosidase and substrate were optimized.After the effects of sample solvent(DMSO) used in the assay and stopping reagent on enzyme activity were assessed,the assay conditions were finally selected.Then 492 kinds of extracts from Guizhou ethno-drugs were screened.Results Practical and sensitive microassay for screening ?-glucosidase inhibitors was successfully constituted.And in 492 kinds of extracts,145 kinds of samples effectively inhibited the enzyme activity.Conclusion The microassay constituted in this work possesses advantages of being rapid,sensitive,reliable,cost saving,easy and flexible.

Comparative study on microassays for screening acetylcholinesterase inhibitors / 中国药理学通报

Aim To provide practical microassays for screening acetylcholinesterase (AChE) inhibitors in drug discovery.Methods The optimal conditions of assaying the activity of AChEs from electric eel,rat brain homogenate and cobra venom were determined in 96-well plates under physiological pH value and temperature by orthogonal matrix method.The concentrations of AChE,substrate and DTNB,and reaction time were optimized.After the effects of sample solvent (DMSO) used in the assay and stopping reagent on enzyme activity were assessed,the assay conditions were finally selected,and 492 kinds of extracts from Guizhou ethno-drugs were screened.Results Practical microassays for screening AChE inhibitors were successfully constituted by using AChEs mentioned above.The data analysis of screening results revealed that electric eel AChE possessed a high sentivity to inhibitors,and cobra venom AChE shared high similarity with rat brain homogenate in positive results.Conclusion Microassays constituted in this work possessed advantages of being easy,rapid,reliable,cost saving and flexible.AChE from electric eel was especially suitable for screening AChE inhibitors from extracts,and AChE from cobra venom was more suitable to be used in screening AChE inhibitors from large numbers of compounds.

Development of an aromatase inhibitor screening assay / 中国药理学通报

Aim To develop an aromatase inhibitor screening a ssa y in vitro. Methods A method termed “tritiated water”assa y was developed to measure aromat aseactivity by quantifying the 3H 2O from the aromatization reaction, us ing placental microsomes as enzyme source and [1?- 3H]androstenedione as a substrate. Result “Tritiated water” assay was establishe d and it was found that androstrenedione had a K m value of 113 nmol?L -1 and a V max value of 33.3 pmol?(min?mg protein) -1 in the aromatiz ation reaction catalyzed by placental microsomes as determined by this assay. The reliability of t his assay was confirmed by application of specific aromatase inhibitor exemestan e. Exemestane was shown to be an irreversible aromatase inhibitor with the IC 50 of 70 nmol?L -1, which was comparable to findings by other laboratories.Conclusion These data demonstrate that “tritiated water” assay is a useful model to screen aromatase inhibitors.

Construction of a drug screening model based on transcription regulation of STAT3 / 中国药理学通报

AIM: To find small molecule organic mimetics of G-CSF, according to the transcription regulating effect of the important transcription factors-STAT3 (signal transducers and activators of transcription3) in hematopoiesis growth factor's signal transductional passageway, we established a drug screening model targeting transcription regulating of STAT3. METHODS: A recombinat vector pTKS3-CAT was constructed. Then pTKS3-CAT and pTK-Hyg were transfected into NFS-60 cells expressing G-CSF receptor with lipofectamine 2000. Cells derived from hygromycin-resistant colonies were tested for CAT activity, and positive colonies were isolated. At the same time, the sensitivity and the specialty of the model were tested. RESULTS: A dose-dependent expression of CAT gene with half-maximal induction by rhG-CSF at 0.044 nmol·L-1 was observed. After treating with rhEPO CAT activity couldn't be tested. CONCLUSION: The expression of CAT gene could be strongly induced by its special ligands in drug screening model. This model can be used to assay CAT from extracts of cells grown with CAT-ELISA method in microtiter wells and then to screen small molecular compounds with G-CSF-like activity.