ABSTRACT
Mayaro virus (MAYV) is a mosquito-transmitted alphavirus that produces an acute, usually non-fatal, febrile illness including Mayaro fever. Like other alphaviruses, the MAYV E1 and E2 envelope glycoproteins are major viral surface antigens that play a key role in host recognition and infection. Here, we report expression and purification methods for recombinant MAYV E1 (rE1) and rE2 using a baculovirus system. Enzyme-linked immunosorbent assays (ELISA) revealed that rE1 and rE2 were antigenic and reacted with human anti-MAYV IgG and IgM. Cross-reactivity was also confirmed with human anti-Chikungunya virus (CHIKV) IgG and IgM. Furthermore, we developed an immunochromatographic strip test (IST) with rE2 to diagnose MAYV infection. Thus, purified rE2 may be valuable tool for rapidly diagnosing MAYV infection.
Subject(s)
Humans , Alphavirus , Antigens, Surface , Baculoviridae , Enzyme-Linked Immunosorbent Assay , Fever , Glycoproteins , Immunoglobulin G , Immunoglobulin MABSTRACT
OBJECTIVE@#To prepare monoclonal antibody against cotinine (COT) and to establish immunoassay for detecting COT in human urinary samples.@*METHODS@#BALB/c mice were immunized with synthesized cotinine-bovine serum albumin (COT-BSA) to screen monoclonal antibody with technique of cell fusion. The monoclonal antibody was used for the indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and colloidal gold immunochromatographic strip assay for the detection of COT in human urine.@*RESULTS@#The monoclonal antibody against COT was identified by ic-ELISA with a 50%inhibitive concentration (IC@*CONCLUSIONS@#The ic-ELISA and colloidal gold immunochromatographic strip assay using the prepared monoclonal antibody against COT have been proved to be reliable for the rapid detection of COT in human urines, which may be used for monitoring of environmental tobacco smoke.
Subject(s)
Animals , Humans , Mice , Antibodies, Monoclonal , Cotinine/urine , Enzyme-Linked Immunosorbent Assay , Gold Colloid , Mice, Inbred BALB C , Urinalysis/methodsABSTRACT
Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/µL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.
ABSTRACT
Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20 480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/μL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.
Subject(s)
Antibodies, Monoclonal/chemistry , China , Chromatography, Affinity/methods , Collodion/chemistry , Colloids/chemistry , Gold Colloid/chemistry , Materials Testing , Membranes, Artificial , Oryza/virology , Plant Diseases/virology , Reproducibility of Results , Sensitivity and Specificity , Species Specificity , Tenuivirus/isolation & purificationABSTRACT
A CdTe/ZnSe quantum-dot submicrobead ( QBs ) , which exhibited fluorescence intensity approximately 2800-fold stronger than that of single quantum dots, was conjugated with the anti-histidine rich protein( HRP )-Ⅱ mAbs using N-( 3-( Dimethylamino ) propyl )-N'-ethylcarbodiimide hydrochloride ( EDC ) method as fluorescence probe. The goat anti-HRP-Ⅱ polyclonal antibodies and donkey anti-mouse polyclonal antibodies were sprayed onto the nitrocellulose membrane as test line and control line, respectively. The resultant fluorescence probes were introduced to the immunochromatographic strip for the quantitative determination of Plasmodium falciparum. For determination of Plasmodium falciparum in serum, the QBs based immunochromatographic strips exhibited a good dynamic linear range from 5 . 8 Parasite/μL to 8010 Parasite/μL with a limit of detection of 5. 8 Parasite/μL. The detection time of the proposed QBs based immunochromatographic strips for each sample was only 15 min. Moreover, the recovery rates of the intra-and inter-assay ranged from 93. 0% to 111. 9%, and 98. 3% to 115. 1% respectively, while the relative standard deviations ( RSDs) of intra-and inter-assay were below 5%.
ABSTRACT
OBJECTIVE: To develop a rapid and sensitive fluorescent immunochromatographic strip for the detection of cefalexin residue. METHODS: The Eu-silica nanoparticles were synthesized by using RP-microemulsion technology. The Eu-silica nanoparticles conjugated with cefalexin monoclonal antibody was used as a fluorescent label. The fluorescent immunochromatographic strip for the detection of cefalexin based on competitive inhibition immunoassay format was developed. The cefalexin-ovalbumin and goat anti-mouse IgG were immobilized on the nitrocellulose membrane as the test line and control line. RESULTS: After experiment optimization, the developed strip could provide detection results within 30 min and the limit of detection of cefalexin was 25 ng·mL-1. There was no cross-reactivity with 12 kinds of antibiotics including cephalosporins and penicillin. CONCLUSION: The fluorescence immunochromatographic strip is rapid, sensitive, and easy to operate, which may be a powerful tool to detect antibiotics in the future.
ABSTRACT
Objective To investigate the epidemiological status of visceral leishmaniasis in Hamangou coal mine area of Korla City of Xinjiang Uygur Autonomous Region.Methods Based on a hint of possible existence of patients, a retrospective survey was carried out house by house to find cases with suspected signs/symptoms of the disease.Meanwhile, a survey on current status was conducted, including physical examination(liver and spleen palpation) to those less than 15 years-old, leishmanin skin test and rk39 immunochromatographic strip test for part of the residents.Bone marrow smears were examined for the cases with clinical signs/symptoms and positive rk39 strip test.Sandflies were collected using routine methods in and around the area, identified, and dissected to find infection of promastigotes.Results Leishmanin skin test was performed in 185 people with a positive rate of 21.1%(39/185), 39 out of 140 local residents who have lived there for more than 6 years showed positive(27.9%) , while all residents who have lived less than 6 years and children under 5 years old were negative.Of the 81 children under 15 years old with a negative skin test, one showed positive for rk39 strip test, and leishmania body was found in the bone marrow smear of this case, so confirmed as visceral leishmaniasis.12 sandfies were identified as Phlebotomus alexandri, and natural infection with promastigotes was found in one sandly.Conclusion The investigation confirms that visceral leishmaniasis is endemic in the Hamangou coal mine area.