Comparison of the infectivity of the laboratory strain AD169 and a clinical isolate of human cytomegalovirus to human smooth muscle cells.

The results displayed by human cytomegalovirus (HCMV) IE/E antigen expression and virus release into the supernatant at various times post infection with a clinical isolate (C3/p5) and AD169 laboratory strain of HCMV, illustrated differences in the biology of these viruses on the various cell lines. While AD169 strain was shown to infect fibroblasts efficiently, it showed a low infectivity profile to smooth muscle cells, whereas C3/p5 displayed comparable infectivity characteristics on both cell lines. Neither virus demonstrated propensity for infecting endothelial cells, although passaging of the C3/p5 for additional 11 passages in endothelial cells provided virus capable of infecting endothelial cells efficiently. These results show that HCMV is capable of infecting smooth muscle cells which could be of relevance to the proposed role of HCMV in atherogenesis and provides further evidence on the adaptation of AD169 to fibroblasts.