Jeanni Fehrsen (Ph.D)
Antibodies are important mediators of immune protection, particularly in the case of many viral diseases. Accordingly, this laboratory concentrates on investigating B cell antigens as well as immunoglobulins and their genes. In addition, it develops and investigates novel immunological reagents aimed at monitoring disease progression, vaccination efficacy and antigen production. Recombinant antibody technology and epitope mapping are central to its research efforts. In addition, it is involved in antibody engineering, epitope mapping and is investigating novel recombinant antibody scaffolds. Using its patented technology platform, it is also able to produce recombinant antibodies for internal or external clients on a cost-recovery basis.
This group exploits phage display to isolate recombinant antibodies and map epitopes on proteins. Random peptide libraries as well as gene- or genome-targeted peptide libraries are used to find antigenically important epitopes and even their encoding genes. The identified proteins are expressed in bacterial or mammalian expression systems.
Using the patented technology platform, recombinant antibodies derived from chicken immunoglobulin genes, single chain variable fragments (scFvs) against a large variety of haptens, proteins and viruses have been isolated. The antibody repertoire has been expanded to include scFvs derived from ostrich immunoglobulin genes. These scFvs have been incorporated into immunoassays, such as ELISAs and lateral flow tests. Some have been engineered to improve their binding, while others were reconstituted to antibody-like molecules (gallibodies) and expressed in a mammalian expression system. In addition, immune libraries are constructed tailored to client specifications. Binding characteristics of the scFvs and their target (or any two binding partners) can be analysed by surface plasmon resonance on a BiacoreX.
Jeanni Fehrsen (Ph.D)
+27 (0)12 529 9257
Research focus: Epitope mapping & Recombinant antibody libraries.
Susan Wemmer (M.Sc)
+27 (0)12 529 9126
Research focus: Recombinant avian antibodies & Animal Ethics.
Wouter van Wyngaardt (M.Sc)
+27 (0)12 529 9224
Research focus: Murine and phage
displayed monoclonal antibodies. Immunoassays.
Ronewa Mutwanamba (B.Sc hons)
Senior Research Technician
+27 (0)12 529 9936
Mathebula, E.M., Faber, F.E., Van Wyngaardt, W., Van Schalkwyk, A., Pretorius, A. and Fehrsen, J., 2017, 'B-cell epitopes of African horse sickness virus serotype 4 recognised by immune horse sera', Onderstepoort Journal of Veterinary Research 84(1), a1313. https://doi.org/ 10.4102/ojvr.v84i1.1313
Abolnik, C, Fehrsen, J, Olivier, A, van Wyngaardt, W, Fosgate, G and Ellis, C. 2013. Serological investigation of highly pathogenic avian influenza (HPAI) H5N2 in ostriches (Struthio camelus). Avian Pathology. DOI:10.1080/03079457.2013.779637.
van Wyngaardt, W, Mashau, C, Wright, I, and Fehrsen, J. 2013. Serotype- and serogroup-specific detection of African horsesickness virus using phage displayed chicken scFvs for indirect double antibody sandwich ELISAs. J. Vet. Sci. 14(1), 95-98. http://dx.doi.org/10.4142/jvs.2013.14.1.95.
Sixholo, J., van Wyngaardt, W., Mashau, C., Frischmuth, J., Du Plessis, D.H. and Fehrsen. 2011. Improving the characteristics of a mycobacterial 16kDa-specific chicken scFv. Biologicals. 39,110-116. doi:10.1016/j.biologicals.2011.01.007
Wemmer, S., Mashau, C., Fehrsen, J., Wyngaardt, W. and du Plessis, D.H., 2010. Chicken scFvs and bivalent scFv-CH fusions directed against HSP65 of Mycobacterium bovis. Biologicals. 38, 407-414. doi:10.1016/j.biologicals.2010.02.002
Fehrsen, J., van Wyngaardt, W., Mashau, C., Potgieter, C., Chaudhary, V.K., Gupta,A., Jordaan, F. and du Plessis, D.H., 2005. Serogroup-reactive and type-specific detection of bluetongue virus antibodies using chicken scFvs in inhibition ELISAs. Journal of Virological Methods. 129(1), 31-9.
Van Wyngaardt W, Malatji T, Mashau C, Fehrsen J, Jordaan F, Miltiadou DR, Du Plessis DH. A large semi-synthetic single-chain Fv phage display library based on chicken immunoglobulin genes. BMC Biotechnology. 2004 Apr 1;4(1):6.
Van Wyngaardt W., Du Plessis, D.H., Van Wyngaardt, S. & Verschoor, J.A. 1992. Production and properties of monoclonal antibodies against African horsesickness serotype 3. Onderstepoort Journal of Veterinary Research. 59, 129-133.
Van Wyngaardt W. and Du Plessis, D.H., 1998. Selection of an scFv pahge antibody that recognises bluetongue virus from a large synthetic library and its use in ELISAs to detect viral antigen and antibodies. Onderstepoort Journal of Veterinary Research. 65, 125-131.
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