Replication of Merkel cell polyomavirus (MCPyV) in human cell lines

The Merkel cell polyomavirus (MCPyV) is the only human polyomavirus classified as probably carcinogenic to humans and is the causal factor of a rare aggressive skin malignancy the Merkel cell carcinoma (MCC) in around 80% of cases. Nevertheless, in addition to skin the virus was detected in various body tissues. In spite of that an ideal in vitro model system is still lacking. Three MCPyV isolates from healthy human skin are studied in this diploma thesis. The isolates harbour mutations, one has mutations is its LT coding gene, one has a rearranged non-coding control region (NCCR), and one is identical to the reference MPCyV isolate R17b. In this diploma thesis the replication capacities of the isolates were studied with the emphasis on the impact of a duplication within the NCCR and mutations on MCPyV genome replication in vitro after transfection. First, the results show that the NCCR rearrangement and the mutations in the viral protein coding genes impact the MCPyV replication in the 293 cell line. Preliminary data suggest the NCCR rearrangement negatively influences the MCPyV replication but certain mutations in protein coding genes could increase the replication. Moreover, none of the isolates replicated in the 293T cell line. The next part of the thesis focused on the replication of the MCPyV..