Scientists at the University and University Hospital of Lausanne, Switzerland, have developed diagnostic tests to detect two intracellular bacteria, Waddlia chondrophila and Parachlamydia acanthamoebae, which are associated with miscarriage and pneumonia.
While miscarriage affects as many as 15 per cent of clinically-recognised pregnancies, a cause is identified in only 50 per cent of all miscarriages. Recent studies have demonstrated that W. chondrophila is associated in more than 31 per cent of miscarriages, whereas P. acanthamoebae is associated to 1.6 per cent.
Similarly, the incidence of pneumonia is increasing, and current diagnostics fail to identify a causative agent in approximately 50 per cent of cases. As is the case in miscarriage, studies of blood samples of infected patients have demonstrated an association of P. acanthamoebae with up 13 per cent of patients with pneumonia.
The new tests use antibodies in the diagnosis of infection by these intracellular microorganisms.
In order to develop the tests, the genomes of W. chondrophila and P. acanthamoebae were sequenced and immunogenic proteins identified. The sequences of these proteins were analysed, and those displaying high sequence homology with similar proteins in other species were discarded to avoid cross-reactivity.
Recombinant proteins were tested by ELISA to confirm their reactivity and selectivity. In addition to their use in human medicine, these diagnostic tools are also the veterinary sector
Having completed the proof-of-concept phase, commercial kits are being developed, and patents have been filed (EP08172133.4 and EP09172401.3).