Objective:To establish an in vivo infection model of West Nile virus (WNV) pseudovirus and evaluate the neutralizing activity of antibody WNV-XH1.Methods:A stable cell line that can package the WNV pseudovirus was established in the early stage to prepare the pseudovirus supernatant. The supernatant was concentrated and infected BHK21 cells to detect the titer of the pseudovirus. After intraperitoneal injection of the pseudovirus into C57BL/J mice, bioluminescence imaging was performed to observe the infection status of the pseudovirus in the mice. After simultaneous infection, blood was collected and ELISA was used to detect NS1 levels in mouse serum. The in vivo functional activity of antibody WNV-XH1 was evaluated using the established mouse infection model.Results:Fluorescence was detected in C57BL/J mice infected with WNV pseudovirus, and the NS1 levels in the peripheral blood serum of mice infected with pseudovirus were significantly higher than those of non infected mice (1.453±0.09vs0.305±0.018). After intravenous administration of WNV-XH1 antibody before the attack, the fluorescence signal in the mice decreased and the serum NS1 level decreased (0.384±0.015).Conclusions:A successful in vivo infection model of WNV pseudovirus was established, and it was confirmed that the antibody WNV-XH1 had a protective effect against WNV pseudovirus infection in vivo.

Objective:To prepare and identify a broad-spectrum antibody FHA3 targeting influenza A virus hemagglutinin (HA).Methods:According to the single-chain antibody fragment (scFv) sequence, the heavy chain (VH) and light chain (VL) variable regions of FHA3 were amplified by PCR and a recombinant plasmid pFRT-IgG1κ-FHA3 was constructed by linking the expression vector pFRT-IgG1κ. FHA3 was expressed in the ExpiCHO system and purified by affinity purification. The binding activity of FHA3 to influenza A virus HA was detected by ELISA. The neutralizing activity of FHA3 was detected in vitro by infecting host cells with pseudovirus. Results:SDS-PAGE showed that high-purity FHA3 was obtained. FHA3 could bind to H1N1 HA, H2N2 HA, H3N2 HA, H5N1 HA, H7N9 HA and H9N2 HA in a concentration-dependent manner. FHA3 had good neutralizing activity in vitro that was it could effectively block the invasion of H5N1 and H7N9 pseudoviruses into target cells at a low concentration of 5 μg/ml and H1N1 pseudovirus at 0.012 5 μg/ml. Conclusions:A broad spectrum antibody targeting HA protein of influenza A virus with neutralizing activity in vitro was obtained.

Objective:To prepare and identify a functional antibody FNA1 targeting the neuraminidase (NA) of influenza A virus N1 subtype.Methods:According to single-chain antibody fragment (scFv) sequence, the heavy chain and light chain variable region sequences of FNA1 were synthesized, and the recombinant expression plasmid pFRT-IgG1κ-FNA1 was constructed by linking the expression vector pFRT-IgG1κ. The FNA1 antibody was expressed in ExpiCHO cells and purified using affinity purification technique. The binding ability of FNA1 to the target proteins, influenza A virus N1 subtype NA antigens, was detected by ELISA. Flow cytometry was performed to analyze the binding ability of FNA1 to the NA antigens expressed on the surface of cell membrane. The in vitro activity of FNA1 against NA was evaluated by infecting 293T cells with pseudovirus. Results:Protein electrophoresis showed that FNA1 with high purity was obtained. FNA1 specifically recognized and bound to N1 subtype NA antigens in a concentration-dependent manner. FNA1 could effectively block NA activity by binding to N1 subtype NA protein expressed on the surface of cell membrane, thus inhibiting the release of packaged pseudovirus from cell surface and further inhibiting target cell infection.Conclusions:An antibody FNA1 targeting influenza A virus N1 subtype NA with in vitro functional activity was obtained.

Roundworms of Toxocara canis and Toxascaris leonina are common gastrointestinal helminths of canids over the world. Humans are infected with T. canis larvae through ingestion of infective eggs in contaminated environments or larvae by consumption of raw or uncooked meat or livers. Recently, patients of clinically diagnosed toxocariasis are increasing and require correct diagnosis in Korea. The present study investigated serological cross-reactivity between crude antigens of T. canis (TCLA) and T. leonina (TLLA) larvae. We collected serum specimens from 177 toxocariasis patients who were clinically suspected in the Seoul National University Hospital and 115 healthy controls. An ELISA method for toxocariasis was used to evaluate diagnostic efficacy of TLLA for serodiagnosis of human toxocariasis. The IgG ELISA using TLLA gave 14 (14.3%) positives of 98 TCLA positive specimens among 177 suspected toxocariasis patients. Most of them showed high absorbances with TCLA. In conclusion, there is a partial cross reaction between serum specimens of toxocariasis and TLLA.
Animals ; Antibodies, Helminth/blood ; Antigens, Helminth/*immunology ; Cross Reactions ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin G/blood ; Larva/immunology/metabolism ; Toxascaris/growth & development/*immunology/isolation & purification ; Toxocara canis/growth & development/*immunology/isolation & purification ; Toxocariasis/*diagnosis/parasitology

Evoked Potentials ; Humans ; Magnetic Resonance Imaging ; methods ; Optic Neuritis ; diagnosis ; Retrospective Studies

Toxocariasis is a worldwide zoonosis caused by larvae of ascarid nematodes of dogs or cats, Toxocara canis or T. cati. Diagnosis of human toxocariasis currently relies on serology that uses T. canis excretory-secretory antigen to detect specific IgG antibodies by ELISA. We investigated the serodiagnostic efficacy of ELISA using crude antigen of T. canis larvae (TCLA). Serum specimens of 64 clinically confirmed toxocariasis, 115 healthy controls, and 119 other tissue-invading helminthiases were screened by ELISA using TCLA. The ELISA using TCLA showed 92.2% (59/64 patient samples) sensitivity and 86.6% (103/119) specificity. Its positive diagnostic predictivity was 78.7% and negative predictivity was 97.8%. No serum of healthy controls reacted but that of anisakiasis (45.5%), gnathostomiasis (19.2%), clonorchiasis (15.8%), sparganosis (11.1%), and cysticercosis (6.3%) cross-reacted. Immunoblot analysis on TCLA recognized antigenic proteins of 28- and 30-kDa bands in their dominant protein quantity and strong blotting reactivity. The present results indicate that the ELISA using our TCLA antigen is acceptable by the sensitivity and specificity for serodiagnosis of human toxocariasis. ELISA with TCLA is recommended to make differential diagnosis for patients with any sign of organ infiltration and eosinophilia.
Adolescent ; Adult ; Aged ; Animals ; Antigens, Helminth/chemistry/*diagnostic use/immunology/isolation & purification ; Cats ; Dogs ; Enzyme-Linked Immunosorbent Assay/*methods ; Female ; Humans ; Larva/chemistry/immunology ; Male ; Middle Aged ; Serologic Tests ; Toxocara canis/chemistry/*immunology ; Toxocariasis/*diagnosis/immunology/parasitology ; Young Adult

We optimized the conditions of mixed fermentation of very high gravity ethanol with cassava flour and sugarcane juice. Based on the single factor experiment, we screened the important parameters for very high gravity ethanol fermentation with cassava flour and sugarcane juice by the Plackeet-burman design. Then, we obtained the optimum values of the important parameters by the orthogonal experiments: the mixing ratio of cassava flour to sugarcane juice, 1:5; initial pH of fermentation, 4.0-4.5; the concentrations of urea and MgSO4, 0.25% and 0.04% (W/W), respectively. Finally, we used a gradient temperature control strategy with the optimized conditions, and ethanol concentration of 17.84% (V/V) and fermentation efficiency of 91.82% were achieved, correspondingly.
Biofuels ; analysis ; Ethanol ; analysis ; metabolism ; Fermentation ; Hydrogen-Ion Concentration ; Manihot ; metabolism ; Powders ; Saccharum ; metabolism

Gene therapy refers to the introduction of normal genes into human target cells for correcting gene defects or exerting therapeutic action,and thus achieves the goal of treatment of disease.Bone marrow stromal cells (BMSCs) are stem cells that possess self-renewal and multi-directional differentiation potential and easy to amplify in vitro,and they also express many therapeutic exogenous genes in vitro or in vivo.So BMSCs have been regarded as an ideal target cell of cell and gene therapy.This article reviews the biological characteristic of BMSCs,some commonly used gene therapy vectors and their applications in gene therapy of central nervous system diseases.

A cohort was established for evaluation of cancer risk factors in Sancheong-gun, Gyeongsangnam-do, Korea. As one of the cohort studies, stools of 947 residents (403 males and 544 females, age range: 29-86 years) were screened for Clonorchis sinensis eggs using both Kato-Katz method and formalin-ether sedimentation technique. The overall egg positive rate of C. sinensis was 37.7% and individual EPG (eggs per gram of feces) counts ranged from 24 to 28,800. Eight egg positive residents voluntarily joined a process of collection of the passed worms after praziquantel treatment. A total of 158 worms were recovered from 5 of the 8 treated persons, ranged from 3 to 108 in each individual. The worms were 15-20 mm x 2-3 mm in size, and showed brown-pigmented, red, or white body colors. This is the first collection record of C. sinensis adult worms from humans through anthelmintic treatment and purgation. The adult worms of C. sinensis may be paralyzed by praziquantel and then discharged passively through bile flow in the bile duct and by peristaltic movement of the bowel.
Adult ; Aged ; Aged, 80 and over ; Animals ; Antiplatyhelmintic Agents/*therapeutic use ; Clonorchiasis/*drug therapy/epidemiology/*parasitology ; Clonorchis sinensis/anatomy & histology/*isolation & purification ; Feces/parasitology ; Female ; Humans ; Korea/epidemiology ; Male ; Middle Aged ; Neoplasms/epidemiology ; Parasite Egg Count ; Praziquantel/*therapeutic use ; Risk Factors

We investigated a small-scale serological survey to screen tissue-parasitic helminthiases of North Koreans as one of research programs for re-unification of Korea. Soil-transmitted helminthiases were found highly prevalent among North Korean residents at the border with China. ELISA using 4 tissue-parasitic helminth antigens was applied to 137 residents living in Cheongjin-shi, Hamgyeongbuk-do, North Korea and 133 female refugees in South Korea in 2004-2005. Among a total of 270 samples, 31 (11.5%), 25 (9.3%), and 11 (4.1%) were positive for specific IgG antibodies to antigens of Clonorchis sinensis, Taenia solium metacestode, and sparganum, respectively. The overall positive rate was 21.5%; 38.2% in males and 15.8% in females. The present finding suggests that tissue parasites, such as C. sinensis, T. solium metacestode and sparganum are highly prevalent in some limited areas of North Korea. These foodborne tissue-parasitic helminthiases should be considered for future control measures of parasitic diseases in North Korea.
Adolescent ; Adult ; Aged ; Animals ; Antibodies, Helminth/blood ; Antigens, Helminth/blood ; Child ; Child, Preschool ; Clonorchis sinensis/isolation & purification ; Enzyme-Linked Immunosorbent Assay ; Female ; Helminthiasis/*epidemiology/*parasitology ; Humans ; Immunoglobulin G/blood ; Korea/epidemiology ; Male ; Middle Aged ; Prevalence ; Seroepidemiologic Studies ; Sparganum/isolation & purification ; Taenia solium/isolation & purification