Objective:Study on characteristics of two synthesizd peptides based on CSFV E2 protein. Methods:B cell epitopes of CSFV E2 antigen were predicted using accessibility and flexibility schemes, associated with antigenicity , secondary structure and multiple sites prediction. Two antigen peptides (Pep1 and Pep2) have been designed and synthesized and their reactivety were detected with 8 McAbs and antiserum against mE2 protein, then the peptides were conjugated with BSA and immunized rabbits respectively. Results:Both Pep1 and Pep2 could react with antiserum and McAb A11, Pep2 could interact with McAbD5 and McAbD8. Only Pep1 BSA conjugate can stimulate high level and specific antibodies.Conclusion: The peptide1 has good antigenicity.

Aim: To prepare a fully human anti-VEGF_(165)(vascular endothelial growth factor 165) monoclonal antibody with antitumor activity from five-feature mice which express human immunoglobin loci. Methods: A routine method for the generation of monoclonal antibodies( mAbs) against the human VEGF_(165) was developed. The immunizing effect between five-feature mice and BALB/c was observed and the mAb was purified through MBP IgM affinity chromatography. The effect of mAbs on antitumor was tested ire vitro by T24 cell line. Results: Four hybri-domata secreting mAbs steadily were isolated successfully, and the serum titer of mAb in BALB/c mice was almost 10 times higher than that in five-feature mice. The indirect ELISA method for mAb titer determination was also established. The anti-VEGF_(165) mAb was purified to homogeneity by precipitation with ammonium sulfate followed by the affinity chromatography on MBP IgM purification column. Moreover, both purified human IgM V_2, V_(75) and mouse ascites were characterized by SDS-PAGE and Western blotting. Proliferation of T24 cell line was considerably inhibited by V_2 and V_(75). Conclusion: Five-feature mice could be used to produce fully human monoclonal antibody. The fully human anti-VEGF mAb is potential in the cancer treatment.

Objective To conduct cloning, sequencing and expression of Trichinella spiralis ES antigen p49 gene. Methods RT-PCR was used to amplify the specific gene fragment from the total RNA of Trichinella spirais larvae. The PCR product was ligated to the T-vector and the recombinant plasmid was verified by sequencing. T-p49 and pGE-4T-3 were treated by both BamHI and XhoI. The ligation reaction was catalyzed by T4 DNA ligase. Results The p49 gene was cloned by using RT-PCR. Sequence analysis showed that the p49 gene obtained was consistent to the p49 sequence reported in the database. The expressed protein was shown as a new band at SDS-PAGE. BLAST analysis demonstrated that this p49 gene was 99% identical to the p49 gene reported and to the 43 kDa secreted glycoprotein gene in the database. Conclusion p49 gene from Trichinella spiralis larvae was cloned, sequenced and expressed.

In producing transgenic livestock, selectable marker genes (SMGs) are usually used to screen transgenic cells from numerous normal cells. That results in SMGs integrating into the genome and transmitting to offspring. In fact, SMGs could dramatically affect gene regulation at integration sites and also make the safety evaluation of transgenic animals complicated. In order to determine the deletion time and methods in the process of producing transgenic goats, the feasibility of deleting SMGs was explored by Cre/LoxP before or after somatic cell cloning. In addition, we compared the efficiency of protein transduction with plasmids co-transduction. We could delete 43.9% SMGs after screening out the transgenic cell clones, but these cells could not be applied to somatic cells cloning because of serious aging after two gene modifications. The SMG-free cells suitable for nuclear transfer were accessible by using the cells of transgenic goats, but this approach was more time consuming. Finally, we found that the Cre plasmid could delete SMGs with an efficiency of 7.81%, but about 30% in SMG-free cells had sequences of Cre plasmid. Compared with Cre plasmid, the integration of new exogenous gene could be avoided by TAT-CRE protein transduction, and the deletion rate of TAT-CRE transduction was between 43.9 and 72.8%. Therefore, TAT-Cre transduction could be an effective method for deleting selectable marker genes.
Animals ; Animals, Genetically Modified ; genetics ; Cloning, Organism ; veterinary ; Gene Knockout Techniques ; Gene Targeting ; methods ; Genes, Reporter ; Genetic Engineering ; Genetic Vectors ; genetics ; Goats ; genetics ; Integrases ; chemistry ; metabolism ; Recombination, Genetic ; Transgenes ; genetics

Objective To explore the expression of miRNA-181a (miR-181a) in patients with multiple myeloma (MM) and its effect on biological features of MM cells. Methods CD138+cells of bone marrow from 25 MM patients and 10 patients with hematological non-malignancies were purified by using immunomagnetic separation, and the expression of miR-181a in CD138+cells and MM cell lines including RPMI 8226, H929 and U266 were detected by real-time quantitative PCR. The effects of down-regulation and up-regulation of miR-181a expression on the biological characteristics of MM cells were studied with miR-181a antagomir and agomir. Results Compared with patients with hematological non-malignant diseases, the expression of miR-181a in CD138+ cells was upregulated in MM patients. Compared with CD138+ cells in hematological non-malignancies, high expressions of miR-181a were observed in RPMI 8226 and U266 myeloma cell line, while low expressions of miR-181a were observed in H929 cells. Down-regulation of miR-181a with 100 nmol/L miR-181a antagomir could inhibit the proliferation of U266 cells at 24,48 and 72 h [(67.1 ± 3.3) %vs. (50.5 ± 4.1) %, (71.5 ± 3.6) % vs. (52.3 ± 2.2) %, (78.1 ± 5.4) % vs. (69.5 ± 4.3) %, P < 0.05 respectively], whereas up-regulation of miR-181a with 100 nmol/L miR-181a agomir could significantly promote the proliferation of H929 cells at 24 h and 48 h [(21.2 ± 2.4) %vs. (38.5 ± 3.6) %, ( 61.3 ± 5.4) %vs. (82.2 ±6.9)%, P<0.01 respectively]. Cell cycle analysis showed that miR-181a antagomir made U266 cell cycle arrest in the G0/G1 phase. Meanwhile, susceptibility test results indicated that the apoptosis of U266 cells induced by doxorubicin, paclitaxel and 5-fluorouracil was increased when the proliferation of miR-181a expression was down-regulated with miR-181a antagomir. In migration assay, the data showed that down-regulation of miR-181a with miR-181a antagomir could inhibit the migration of U266 cells, and the proportion of migrated cells in the experimental group (62 ± 10) %was lower than that in the control group (89 ± 12) %(P< 0.05), whereas up-regulation of miR-181a with miR-181a agomir could improve the migration of H929 cells, and the proportion of migrated cells in the experimental group (242 ± 9) % was higher than that in the control group (98 ± 8)%(P<0.01). Conclusions The high expression of miR-181a expressed highly by MM cells may promote the proliferation, migration and drug resistance of myeloma cells, indicating that miR-181a could be an important prognostic biomarker candidate, and the application of gene silencing may improve the prognosis of MM.

In the application of therapeutic antibodies, large molecular weight of antibodies is always a problem that prevents them from penetrating into tissues or binding to antigenic determinants. To overcome this problem, we investigated the function of the heavy chain variable domain of a monoclonal anti-VEGF human IgM antibody derived from the Five-Feature Translocus Mice. We cloned the cDNA of the heavy chain variable domain, which was then inserted into pET28a vector and expressed in Escherichia coli. After purification and renaturation of the denatured recombinant protein, we obtained a 16 kDa antibody fragment, which is named as rhVVH. By immunoassaying its VEGF-binding capability in vitro, we proved that rhVVH retains this activity as the complete IgM. Importantly, rhVVH is shown to inhibit the HUVEC cell proliferation in a concentration-dependent manner. Our results indicate that the single heavy chain variable domain might inherit part of the biological function of the complete IgM antibody, which provided a valuable potential in further research on antibody miniaturisation.
Amino Acid Sequence ; Animals ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Humans ; Immunoglobulin Heavy Chains ; biosynthesis ; genetics ; Immunoglobulin Variable Region ; biosynthesis ; genetics ; Mice ; Molecular Sequence Data ; Recombinant Proteins ; biosynthesis ; genetics ; Single-Chain Antibodies ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor A ; genetics ; metabolism

Objective To evaluate the bacteriostatic effect of recombinant human lactoferrin(rhLF) on Helicobacter(H .) py‐lori and its influence on CagA ,Ure and gastric mucosal IL‐8 .Methods The minimum inhibitory concentration(MIC)and the influ‐ence of different drug concentrations on the proliferation of H .pylori were detected .The effects of rhLF on the mRNA and protein expressions of CagA and Ure in H .pylori were detected by RT‐PCR and Western blot ,respectively .The animal study :Balb/c mice were adopted and assigned randomly into four groups ,including the standard triple+rhLF(group A) ,rhLF(group B) ,standard tri‐ple(group C) and normal saline(group D) .The histopathological HE staining was used to observe the gastric inflammation and ELISA was used to detect the IL‐8 level of gastric tissue in each group .Results MIC was 0 .5 mg/mL ,moreover rhLF inhibited the bacterial growth and proliferation with a concentration‐dependent manner .rhLF could reduce the expression of H .pylori major viru‐lence factor CagA ,mRNA and protein of Ure .Comparing the group A with the group B ,C and D ,the gastric mucosal inflammation score and the IL‐8 levels of gastric tissue homogenates had statistically significant differences(P<0 .05) .Conclusion rhLF inhibits the growth and proliferation of H .pylori ,moreover inhibit the expression of major virulence factor CagA in H .pylori ,mRNA and protein of Ure in different degrees ,weakens its pathogenicity ,meanwhile reduces the IL‐8 level in mice gastric mucosa ,and allevi‐ates H .pylori related gastric mucosal inflammatory response .

Chronic myelomonocytic leukemia(CMML)complicated with immune thrombocytopenia(ITP)is rare.This article reports the clinical data of a patient with CMML complicated with ITP treated with a combination of venetoclax,ripertamab(an anti-CD20 monoclonal antibody),and hetrombopag.The coexistence mechanism of CMML and ITP needs to be further clarified.Venetoclax combined with anti-CD20 monoclonal antibody and thrombopoietin receptor agonist may be an effective strategy for the treatment of this complication.

Objective:To explore the changes of dynamic cerebral autoregulation ability in pilots exposed to acute positive acceleration(+ Gz) by transcranial Doppler combined with beat-to-beat blood pressure.Methods:A total of 26 pilots enrolled in the + 8Gz manned centrifuge trial at the Air Force Medical Center, Air Force Medical University from June to October 2022 were prospectively included. Blood pressure and heart rate were monitored in the resting state before the trial and within 5 min after centrifugation. Transcranial Doppler combined with noninvasive continuous beat-to-beat blood pressure monitor were used to detect bilateral middle cerebral artery blood flow velocity and beat-to-beat pulse pressure respectively. The transfer function analysis was applied to derive the parameters of cerebral blood flow autoregulation in each frequency band from 0.02 to 0.50 Hz, and the phase, gain and coherence were calculated. The above parameters were compared between resting state and after acute + 8Gz positive acceleration exposure.Results:Compared with the resting state, in all of the 26 pilots after acute + 8Gz positive acceleration exposure, the systolic and diastolic blood pressure and heart rate increased significantly ( P<0.001), the phase significantly increased and the gain significantly decreased in the ultra-low frequency band (0.02-0.07 Hz) ( P<0.05); whereas there were no statistical differences of gain and phase in the low frequency band (0.07-0.20 Hz) and the high frequency band (0.20-0.50 Hz) (all P>0.05). Conclusions:Transcranial Doppler combined with beat-to-beat pulse pressure can be used for the assessment of changes in immediate dynamic cerebral autoregulation after acute + Gz exposure, and transfer function analysis of ultra-low frequency band parameters is suitable for this type of evaluation.

Objective:To compare the values of medical image technologies in evaluating the tansperineal laser ablation (TPLA) in canine prostate.Methods:TPLA (3 W/600 J and 3 W/1 200 J) were operated in the prostate of six adult male beagles guided by transrectal ultrasound (TRUS). TRUS, transrectal contrast-enhanced ultrasound (TR-CEUS) and multiparameter magnetic resonance imaging (mpMRI) were used to evaluate the ablation on the day of TPLA, one week and one month after TPLA. The animals were sacrificed for pathology to calculate the volume of the ablation. SPSS 22.0 software was used for statistical analysis.Results:TRUS could be used to guide and observe the puncture and ablation process during TPLA. TR-CEUS and contrast enhanced MRI showed good consistency in the volume of ablation ( P>0.05). One month after TPLA, the ablation volume were (1.69±0.51)ml vs (1.73±0.36)ml vs (1.52±0.41)ml (3 W/600 J) and (2.23±0.54)ml vs (2.34±0.29)ml vs (2.19±0.34)ml (3 W/1 200 J) measured by the two medical image technologies and pathology, with good consistency ( P>0.05). Conclusions:TRUS can be used to guide and observe the puncture and ablation process during TPLA. TR-CEUS and mpMRI can be used for postoperative evaluation and follow-up of TPLA. The former has advantages of real-time and low price, which can be promoted and applied in clinical practice.