Acanthamoeba-bacteria: a model to study host interaction with human pathogens.

Acanthamoebae are free-living amoebae distributed worldwide. They are among the most prevalent protozoa found in the environment, and have been isolated from a wide variety of public water supplies, swimming pools, bottled water, ventilation ducts, soil, air, surgical instruments, contact lenses, dental treatment units and hospitals. Acanthamoebae feed on bacteria by phagocytosis, but some bacteria are able to survive and sometimes multiply in the host, resulting in new properties of the bacteria. The intracellular growth of bacteria has been associated with enhanced environmental survival of the bacteria, increased virulence and increased resistance against antibiotic substances. The advantage of utilising free-living amoebae is that research can be carried out on non-mammalian cells as a model based on natural reality to study bacterial virulence and pathogenicity. Amoebae are easy to handle experimentally compared with mammalian cells and allow studies on host factors for host-parasite interactions. Bacteria are easily manipulated genetically, which creates the possibility of research on mutants to study bacteria-host interactions. Thus utilising this non-mammalian model can result in better understanding of interactions between prokaryotic and eukaryotic cells and assist in the development of new therapeutic agents to recognise and treat infections.