Abstract
Rabies post-exposure prophylaxis (PEP) currently comprises administration of rabies vaccine together with rabies immunoglobulin (RIG) of either equine or human origin. In the developing world, RIG preparations are expensive, often in short supply, and of variable efficacy. Therefore, we are seeking to develop a monoclonal antibody cocktail to replace RIG. Here, we describe the cloning, engineering and production in plants of a candidate monoclonal antibody (E559) for inclusion in such a cocktail. The murine constant domains of E559 were replaced with human IgG1κ constant domains and the resulting chimeric mouse-human genes were cloned into plant expression vectors for stable nuclear transformation of Nicotiana tabacum. The plant-expressed, chimeric antibody was purified and biochemically characterized, was demonstrated to neutralize rabies virus in a fluorescent antibody virus neutralization assay, and conferred protection in a hamster challenge model.
Highlights
Presented in part: The Fifth International Conference on Plant-based Vaccines, Antibodies and Biologics (5–7 June, 2013), University of Verona, Italy
Rabies neutralizing antibodies are directed against the viral glycoprotein, and several studies have demonstrated that rabies-specific monoclonal antibodies (mAbs) can protect rodents after rabies virus (RABV) challenge [18,19,20,21,22,23]
Cloning of Antibody Heavy and Light Chain Genes From Hybridoma E559.9.14 The murine immunoglobulin γ1 heavy and κ light chain genes expressed by the E559.9.14 hybridoma were amplified by polymerase chain reaction, using first strand complementary DNA (cDNA) as template
Summary
Presented in part: The Fifth International Conference on Plant-based Vaccines, Antibodies and Biologics (5–7 June, 2013), University of Verona, Italy. In the developing world, these serumderived antibodies often suffer from drawbacks including limited availability, batch-to-batch variation, high cost, contamination with blood-borne adventitious agents, and/or risk of adverse reactions [12]; for these reasons, the World Health Organization (WHO) encourages the development and evaluation of alternative biologics for RIG replacement [13]. One such alternative is offered by monoclonal antibodies (mAbs) that are capable of neutralizing a wide range of RABV isolates [12, 14,15,16,17,18]. Several groups have characterized RABV-neutralizing mAbs [14, 17, 25,26,27,28,29,30], and the World Health Organization Rabies Collaborating Centers (WHO RCCs) identified 5 murine mAbs [15], with 4 (E559.9.14, M727-5-1, M777-16-3 and 1112-1) recognizing antigenic site II of the glycoprotein and 1 (62-71-3) recognizing antigenic site I [31]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
