More information about Scicons
Scicons is now a part of Nordic-MUbio. They manufacture three mouse monoclonal antibodies that bind to double-stranded RNA molecules: their anti-dsRNA antibodies can be used as a diagnostic tool to detect whether an unknown pathogen is bacterial or viral in nature, including detection in paraffin-embedded fixed tissue samples.
The hybridomas that produce the J2, K1 and K2 antibodies were created in 1990, and their specificity, their binding to a range of synthetic double stranded polyribonucleotides and their lack of reaction with DNA and single stranded RNA has been extensively characterised (Schönborn et al., 1991).
J2 monoclonal antibody (mAb), mouse, IgG2a, kappa chain
The J2 anti-dsRNA IgG2a monoclonal antibody has become the Gold Standard in dsRNA detection. It was used initially for the study of plant viruses, but since the seminal paper of Weber et al. in 2006, where J2 was used to show that all the positive strand RNA viruses tested produced copious amounts of dsRNA in infected cells, this antibody has been used extensively in a wide range of systems, as documented in over 200 scientific publications.
J2 can be used to detect dsRNA intermediates of viruses as diverse as Hepatitis C virus, Dengue virus, rhinovirus, Chikungunya virus, Rabies virus, Polio virus, Classic swine fever virus, Brome mosaic virus and many more in cultured cells and also in fixed paraffin-embedded histolog-ical samples.
J2 has been used to elucidate how anti-viral responses are initiated, what counter-strategies viruses have adopted to avoid them, and to explore the viral life cylce by enabling ultrastructiural localisation studies of viral nucleic acid replication sites (Welsch et al., 2009 & Knoops et al., 2011).
J2 has been used successfully in electron microscopy, in immunofluorescence microscopy, in immunohistochemistry, and various immuno-capture methods, such as dot blots and ELISA. J2 has also been recommended as a diagnostic tool to detect whether an unkown pathogen is bacterial or viral in nature (Richardson et al., 2010). Recently J2 has also been used to monitor the removal of dsRNA from in vitro synthesized mRNA preparations that may have potential use in gene therapy (Kariko et al., 2011).
K1 monoclonal antibody (mAb), mouse, IgG2a, kappa chain
The K1 IgG2a monoclonal antibody recognises dsRNA with similar affinity to our widely used J2 antibody and is also sold in lyophilised form. It can be used for the histological and cytological detection of dsRNA in cells and tissues.
It has proven especially useful as an alternative to J2 to resolve cross-reactions and/or remove unwanted background, in those rare experi-mental setups where J2 did not provide satisfactory results.
K1 can be used to detect dsRNA intermediates of viruses as diverse as Hepatitis virus, Theiler’s murine encephalomyelitis virus or Japanese encephalitis virus. It has been for the detection of dsRNA in cultured cells and in fixed paraffin-embedded histological samples (see publications).
If Poly I:C needs to be detected we highly recommend using K1 rather than J2 because K1 has a much higher affinity for this synthetic polyribonucleotide (see Schönborn et al. 1991, Fig. 2).
K1 has been used successfully in immunofluorescence microscopy, in flow cytometry (FACS) and in immunocapture methods (such as dot-blot and ELISA).
K2 monoclonal antibody (mAb), mouse, IgM, kappa chain
K2 anti-dsRNA monoclonal antibody has an IgM isotype.
K2 is mainly used for specialised applications, where J2 and K1 - antibodies that can be shipped at ambient temperature - do not suffice. Due to its IgM isotype K2 is more prone to aggregation at high concentration, and therefore cannot be lyophilised and needs to be shipped on ice.
K2 has primarily been used in ELISA and sandwich ELISA. Generally, K2 can be used in applications where an anti-dsRNA antibody with an isotype other than IgG (IgG2a) is required.