Table 1.
Genetic and biological properties of human roseoloviruses and HCMV.
| HHV-6A | HHV-6B | HHV-7 | HCMV | |
|---|---|---|---|---|
| Commonly used strains | U1102, GS | Z29, HST | JI, RK, SB, UCL-1 | AD169, Towne, Merlin, TB40E |
| Length of wild genomes | ? | ~170 kb | ? | 236 kb |
| Length of passaged genomes | 159 kb | 159-162 kb | 145 kb | ~230 kb |
| genes encoding unique proteins | ~102 | ~97 | ~86 | ~165 |
| miRNAs | 4 predicted | 4 | unknown | 16 |
| Replication | slow, extended | |||
| ballooning, refractile cytopathic effect | cytomegaly, nuclear and cytoplasmic inclusions | |||
| origin-binding protein for initiation of DNA replication | ||||
| Cell surface receptor | CD46 | CD134 | CD4 | EGFR, Integrins |
| Cell culture tropism | umbilical cord blood lymphocytes peripheral blood mononuclear cells | monocyte-macrophages | ||
| T cell lines: SupT-1, HSB2, J JAHN | T cell lines: Molt-3, Mt-4, SupT-1 | T cell lines: SupT-1 | CD34+ hematopoietic cells | |
| productive replication in astrocytes | low-level persistence in astrocytes | endothelial and epithelial cells, fibroblasts | ||
| Unique features | integration into host telomeres | |||
| Major disease associations | Hashimoto's thyroiditis | exanthem subitum | congenital birth defects | |
| febrile seizures/ status epilepticus | transplant complications | |||
| transplant complications | retinitis | |||
| post-transplant reactivation-associated encephalitis | hepatitis | |||