Monoclonal antibodies (McAb) were used to develop nonisotopic and radioimmunoassays (RIA) for quantitative determination of the major nicotine metabolite, cotinine, in physiological fluids. ELISAs and fluorescence immunoassays were carried out in microtiter plate wells coated with a conjugate of cotinine 4'-carboxylic acid bound covalently to poly-L-lysine. The detection systems were horseradish peroxidase (HRP)-labeled staphylococcal protein A, HRP-streptavidin-biotin, and biotinylated alkaline phosphatase-4-methylumbelliferyl phosphate. With the three McAb tested, I50 values ranged between 0.024-0.063 ng cotinine and as little as 0.005-0.015 ng gave 15% inhibition. These assays were 5-20 times more sensitive than similar assays using six rabbit antisera. With McAb the standard inhibition curves were steeper and complete inhibition of immune binding was achieved with approximately 1 ng cotinine. In contrast, 100-500 ng cotinine failed to give greater than 80-90% inhibition with rabbit antibodies either in the plate assays or in RIA using a 125I-labeled tyramine derivative of cotinine as the tracer. In this RIA, the sensitivity with McAb (mean I50 of 0.55 ng cotinine) was over three-fold greater than with rabbit antisera (mean I50 of 1.84 ng). The presence of antibodies directed to the amide linkage group common to the polylysine conjugate. 125I-tyramine derivative and the immunogen likely accounts for the inferior quality of assays using rabbit antisera. Consistent with this conclusion, superimposable inhibition curves were obtained in the RIA when monoclonal or rabbit antibodies were used with [3H]cotinine. Cotinine levels in saliva, serum and plasma from smokers and non-smokers determined with McAb-based assays showed a strong correlation with values obtained by RIA using rabbit antisera or by gas chromatography. Properly selected McAb offer distinct advantages over conventional antisera in nonisotopic immunoassays and RIAs for cotinine as a biochemical marker of active or passive smoking.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0022-1759(87)90320-6 | DOI Listing |
Carbohydr Res
January 2025
School of Biotechnology and Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, Jiangnan University, Lihu Ave. 1800, Wuxi, 214122, China; School of Life Sciences and Health Engineering, Jiangnan University, Lihu Ave. 1800, Wuxi, 214122, China; Innovation Center for Vaccine Engineering, Jiangnan University, Lihu Ave. 1800, Wuxi, 214122, China. Electronic address:
Bacterial surface polysaccharides are widely decorated with diverse rare functional groups. An understanding of the role of these functional groups in immunological activity of the glycans is required for the development of carbohydrate-based treatment against bacterial infectious diseases. Here, the antigenicity evaluation of synthetic trisaccharide 1 related to Plesiomonas shigelloides serotype O51 lipopolysaccharide (LPS) O-antigen and its acetamido derivative 2 was achieved to elucidate the immunological importance of O-antigen structure.
View Article and Find Full Text PDFJ Bras Nefrol
January 2025
Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, SP, Brazil.
Background: A new induction therapy strategy of a single 3 mg/kg dose of rabbit antithymocyte globulin (r-ATG) showed a lower incidence of acute rejection.
Methods: The objective of this study was to use real-world data to determine the incremental cost-effectiveness ratio (ICER) of r-ATG induction for the prevention of acute rejection (AR) in the first year following kidney transplantation and for kidney graft survival over 1, 4, and 10 years of post-transplantation from the perspective of the national public healthcare system. A Markov state transition model was developed utilizing real-world data extracted from medical invoices from a single center.
J Infect Dis
December 2024
Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
Background: Enteric fever caused by Salmonella enterica serovars Typhi and Paratyphi A in addition to gastroenteritis and invasive disease, predominantly attributable to nontyphoidal Salmonella serovars Typhimurium and Enteritidis, are major causes of death and disability across the globe. A broad-spectrum vaccine that protects against disease caused by typhoidal and nontyphoidal serovars of Salmonella is not available for humans but would prevent a considerable burden of disease worldwide.
Methods: We previously developed a broad-spectrum vaccine for Gram-negative bacteria that is based on the inner core domain of detoxified Escherichia coli O111, Rc (J5) mutant lipooligosaccharide, a highly conserved antigen across Gram-negative bacteria, complexed with an outer membrane protein of group B Neisseria meningitidis.
PLoS Pathog
December 2024
Department of Medicine, UConn Health, Farmington, Connecticut, United States of America.
The global resurgence of syphilis has created a potent stimulus for vaccine development. To identify potentially protective antibodies against Treponema pallidum (TPA), we used Pyrococcus furiosus thioredoxin (PfTrx) to display extracellular loops (ECLs) from three TPA outer membrane protein families (outer membrane factors for efflux pumps, eight-stranded β-barrels, and FadLs) to assess their reactivity with immune rabbit serum (IRS). We identified five immunodominant loops from the FadL orthologs TP0856, TP0858 and TP0865 by immunoblotting and ELISA.
View Article and Find Full Text PDFFoods
December 2024
Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology (IZI), Perlickstr. 1, 04103 Leipzig, Germany.
Hazelnuts are frequently involved in IgE-mediated reactions and are the main cause of nut allergies in Europe. Most food products are processed before human consumption. Food processing can modify the structure, properties, and function of proteins, and as a result, the IgE-binding capacity of allergens can be affected.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!