Transmissible gastroenteritis(TGE)is a highly contagious gastrointestinal disease of pigs caused by the transmissible gastroenteritis virus(TGEV).It results in severe diarrhea and high mortality in suckling piglets.As no specific treatment available,vaccination is considered to be one of the most cost-effective measures for preventing and controlling TGE.However,the immune protection provided by vaccines based on traditional TGEV strains is becoming inadequate due to the continuous emergence of strong and new strains of the virus,which poses a serious threat to the pig industry's health and development.Therefore,the development of new vaccines with im-proved efficiency and broad-spectrum coverage is urgently needed.This paper aims to summarize the pathogenic structural characteristics of TGEV,discuss the latest advancements in TGEV vac-cine research and development,and propose future strategies for the development of highly effec-tive TGEV vaccines.The findings of this paper can serve as a valuable reference for effectively pre-venting and controlling TGE in clinical practice.

Transmissible gastroenteritis(TGE)is a highly contagious gastrointestinal disease of pigs caused by the transmissible gastroenteritis virus(TGEV).It results in severe diarrhea and high mortality in suckling piglets.As no specific treatment available,vaccination is considered to be one of the most cost-effective measures for preventing and controlling TGE.However,the immune protection provided by vaccines based on traditional TGEV strains is becoming inadequate due to the continuous emergence of strong and new strains of the virus,which poses a serious threat to the pig industry's health and development.Therefore,the development of new vaccines with im-proved efficiency and broad-spectrum coverage is urgently needed.This paper aims to summarize the pathogenic structural characteristics of TGEV,discuss the latest advancements in TGEV vac-cine research and development,and propose future strategies for the development of highly effec-tive TGEV vaccines.The findings of this paper can serve as a valuable reference for effectively pre-venting and controlling TGE in clinical practice.

OBJECTIVETo prepare a single chain antibody (ScFv) of mAb SZ-21 against platelet GPIIIa for its future clinical application.

METHODSThe expression vector pET20b-SZ-21ScFv was constructed and the fusion protein was expressed in E. coli BL21 (DE3) PlysS. The activated fusion protein was obtained after a series of purification steps, including cell breakage, inclusion body solubilization, His-bind resin affinity chromatography and protein refolding.

RESULTSThe fusion protein yields were up to 21% of the total amount of bacteria protein. The ScFv fragment could inhibit ADP-induced platelets aggregation in a dose-dependent manner in vitro and the maximal inhibition rate was obtained at a concentration of 20 micro g/ml. It also reacted with endothelial cells as detected by flow cytometry. Moreover, the ScFv fragment was able to inhibit the binding of fibrinogen to platelet.

CONCLUSIONThe SZ-21ScFv fragment had the activity to inhibit platelets aggregation and the binding of fibrinogen to platelet, being potentially useful for the treatment of thrombotic diseases.

Antibodies, Monoclonal ; pharmacology ; Blood Platelets ; metabolism ; Endothelium, Vascular ; cytology ; Fibrinogen ; metabolism ; Humans ; Immunoglobulin Fragments ; pharmacology ; Platelet Aggregation ; Platelet Glycoprotein GPIIb-IIIa Complex ; immunology ; Recombinant Fusion Proteins ; isolation & purification ; pharmacology

AIM: To further investagate the mechanism of thrombus formation and develop a new remedy of anti-thrombus formation. METHODS: The amplified DNA fragment of vWF-A1 domain was inserted into expression vector with 6?his taq (pQE-31), the recombinant expression vect or was transformed into E coli (strain M15) and induced by IPTG. The recombinant fragment, comprising residues 449-728 of mature vWF subunit, designate rvWF-A1. It was purified by Ni-NTA agarose column and renatured by Tris buffer containin g GSH and GSSG. FACS and platelet aggregometer were employed to analyse the rvWF -A1 function of binding to platelet glycoprotein Ib and inhibiting ristocetin-in duced platelet aggregation. RESULTS: The rvWF-A1 was expressed successfully in E coli, comin g up to 30% of total bacterial protein. Its purify was over 95% through Ni-NTA a garose. It was identified to have ability to bind to GPIb, its biologic activity to inhibit ristocetin-induced platelet aggregation was observed, and the inhibi tive rate was 84 7%. CONCLUSION: The above results indicated that high-level expressi on of rvWF-A1 was successfully achieved in E coli and rvWF-A1 may be an effectiv e antithromotic agent in preventing thrombus formation.