title: Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.
abstract: Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization.
authors.affiliation: Laboratory of Molecular Biology and Genetic Engineering, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
authors.forename: Parul
authors.initials: P
authors.lastname: Kulshreshtha
authors.affiliation: Present address: Centre for Biodesign, Translational Health Science and Technology Institute, Gurgaon, India.
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Tiwari
authors.affiliation: Laboratory of Molecular Biology and Genetic Engineering, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
authors.lastname: Priyanka
authors.affiliation: Structural and Computational Biology Laboratory, Department Of Biotechnology, Netaji Subhas Institute of Technology, New Delhi 110078, India.
authors.forename: Shikha
authors.initials: S
authors.lastname: Joon
authors.affiliation: National Brain Research Center, Manesar, India.
authors.forename: Subrata
authors.initials: S
authors.lastname: Sinha
authors.affiliation: Laboratory of Molecular Biology and Genetic Engineering, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India. Electronic address: rakeshbhatnagar@mail.jnu.ac.in.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Bhatnagar
mesh_terms: D000818:Animals; D000881:Anthrax / Q000276:immunology / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control*; D022122:Anthrax Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D000907:Antibodies, Bacterial / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001408:Bacillus anthracis / Q000235:genetics / Q000276:immunology*; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000276:immunology; D018450:Disease Progression; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006825:Hybridomas / Q000276:immunology; D007106:Immune Sera / Q000737:chemistry; D007116:Immunization, Passive; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D057127:Single-Chain Antibodies / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D016019:Survival Analysis
chemical_list: D022122:Anthrax Vaccines; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D007106:Immune Sera; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies; C030325:anthrax toxin
keywords: Anthrax; Disease-enhancement; Monoclonal antibody; Polyclonal antibody