Respiratory viruses and novel methods for virus discovery

This thesis focuses on respiratory virus infections in humans and the improvement of the VIDISCA virus discovery method. Human coronavirus 229E was identified as early as mid-1960s, but no full-length genome sequence of clinical isolates was available. In chapter 2, the analysis of two full-length genome sequences of clinical 229E isolates is presented. The power of the VIDISCA-454 virus discovery method is demonstrated in chapter 3 with the discovery of a novel TTMV. This novel virus was detected in serum, a relatively convenient clinical material for efficient virus identification because of the absence of cells. More difficult is the detection of novel viruses in respiratory samples because of the massive amount of cells, and thus ribosomes and ribosomal RNA in this sample type. A novel method to improve the detection of respiratory viruses is presented in chapter 4: antibody capture VIDISCA-454, which increases the chance that the virus discovered is indeed linked to the disease because of antibodies raised in the patient. The method was tested on 19 clinical samples that contain a variety of known viruses. The sensitivity of the method is described in chapter 5. In chapter 6, the antibody capture method was successfully used for the identification of a novel HRV-C type. Finally, in chapter 7, a primary cell culture technique is added to the VIDISCA-454 protocol that, in combination with autologous antibody staining, allows not only easy virus discovery and identification, but also determination of the cell tropism of a novel virus. In chapter 8 the result of this thesis are summarized and discussed