The capsid protein of the Hawaii strain of human calicivirus was expressed in the transient MVA/bacteriophage T7 polymerase hybrid expression system in order to examine its processing in mammalian cells. Selected amino acid modifications (an insertion, deletion, and substitution) at the predicted amino terminus of the capsid protein as well as the presence or absence of the ORF3 gene were examined for their effect on capsid expression. The protein was expressed efficiently in cell lines derived from three different species, with most of the expressed protein remaining localized within the cells. There was no evidence for N-linked glycosylation or myristylation of the 57 kDa capsid protein. Hawaii virus-like particles (HV VLPs), efficiently produced in the baculovirus expression system, were not observed in this expression system under the conditions in this study.