Fig.1 The rabies virion.
Fig.2 Aspects of the rabies virus life cycle.
Rabies is a lethal disease of animals and humans, caused by rabies virus infection of the central nervous system. Mass vaccination to eliminate endemic canine rabies as well as pre- and post-exposure prophylaxis in humans exposed to rabies virus have been key in the prevention and elimination of rabies in humans. Nevertheless, due to lack of information and limited access to vaccines, rabies remains an important public health problem in developing countries. Rabies mortality approaches 100% in patients once clinical signs have appeared.
Rabies virus is an enveloped single-stranded RNA virus of the Lyssavirus genus of the Rhabdoviridae family. Rabies viruses have linear, non-segmented, single stranded and negative sense genomes which encodes five proteins: nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G) and polymerase (L). Rabies viruses may be categorized as either fixed (adapted by passage in animals or cell culture) or street (wild type). The use of monoclonal antibodies (mAbs) and genetic sequencing to differentiate street rabies viruses have been helpful in identifying viral variants originating in major host reservoirs throughout the world and suggesting the likely sources of human exposure when a history of definitive animal bite was otherwise missing from a patient's case history.
Fig.3 Schematic overview of the rabies virus genome organization and transcription. (Kip, 2018)
The detection of rabies antigen, antibody, viral RNA, or the isolation of virus establishes a diagnosis of rabies. Because any individual test may not be positive in a patient with rabies, serial serum specimens for detection of rabies antibodies, saliva specimens for culture of virus, and skin biopsies for direct immunofluorescence testing for virus antigen are sometimes necessary, especially when rabies is strongly suspected. Among various rapid diagnosis methods, the direct immunofluorescence (IF) test is the most sensitive and specific method of detecting rabies antigen in skin and other fresh tissue.
N protein is the most conserved protein among lyssaviruses and the second most extensively analyzed of the rabies virus proteins (after G) due to its antigenic properties. It is also a major target for T helper (Th) cells that cross-reacts between different lyssaviruses.
P interacts with the N protein to form N-P complexes and prevent its polymerization and non-specific binding to cellular RNA. P also plays a pivotal role as a cofactor in transcription and replication of the viral genome. Since P protein contains a broadly cross-reactive epitope for all lyssaviruses, mAbs targeting P protein have been proven to be potentially useful for diagnosis and serotyping.
L is responsible for virus replication and transcription of virus genome. It is the catalytic component of the polymerase complex.
M protein is the smallest of the virus proteins. It mediates binding of the viral core to the host membrane where it can initiate the budding.
G protein is a type I membrane glycoprotein with a N-terminal ectodomain. It is responsible for interaction with cellular receptors and the entry of the virus into the host cell and is therefore important in viral pathogenesis by targeting the appropriate cells for infection. It is also important for the induction of a host humoral immune response to rabies virus infection and is the target of virus neutralizing antibodies, as well as for virus specific cytotoxic and Th cells. Because of these important roles, it is the most important immunogenic protein studied.
For global researches, much attention has been paid on the development of mAbs suitable for rabies virus antibody and antigen detection in various assays. Creative Biolabs offers anti-rabies virus antibodies for multiple applications, many species, and in both conjugated and unconjugated forms. Each Antibody indicates the applications for which it has been tested. We possess optimal platform for the high-titer bioproduction of mAbs in a fed-batch process, saving time and costs. In case you are dealing with a complex molecule and/or glycosylated protein, our unique platform is the solution. For the above protein targets, ready-to-use catalogue and customized development services are available. Our high-affinity antibodies will contribute greatly to the success of your projects. A full comprehensive suite of primary antibodies, secondary antibodies and isotype controls are supplied to meet your needs. If you are interested in our products or services, please contact us for more information.