Images and Antibodies—The Potential Applications of Phage Antibody Display to Clinical Microbiology

Clinical Microbiology is a very applied science, trying all the while to use any or all scientific techniques to achieve a very specific purpose: the rapid and accurate diagnosis of infections and infectious diseases. To this end, Clinical Microbiologists have quite unashamedly begged, stolen or borrowed methods and applications from anyone else! This endless plagiarism has left obvious footprints in the subject and has led to the often criticised “patchwork quilt” of approaches used in, for instance, the identification of species and typing of strains within them. Thus, Staphylococcus aureus is identified by an enzyme test (coagulase) and typed using bacteriophage susceptibility patterns, whereas Salmonellae are identified by antigen identification (of somatic or “O” and flagellar or “H” antigens) by serological means (the Kauffmann-White scheme) and Shigellae are identified by a combination of serological analysis and biochemical tests. More recently, molecular biology has been extensively applied (see later). In response to the inevitable and logical question as to why things are done in this empirical and unsystematic way, the answer is simply that they work, work well and, largely, work quickly. This short account advances the thought that phage antibody display (PAD) represents yet another opportunity for a raid by the Clinical Microbiologists and that it seems possible that PAD will offer some of the solutions required to achieve those desirable goals of speed, reliability and accuracy whilst at the same time additionally offering that other, very modern, aspiration of doing so at a low cost. It will be helpful first to examine the needs of Clinical Microbiology.