Investigation of DNA sequences on glycoproteins in VZV Oka vaccine and parental Oka strains *
The Oka vaeeine strain, derived from a Japanese elinieal isolate (the parental Oka strain) of varicella-zoster virus (VZV) through tissue cultures. induces immunity against VZV without clinical manifestations. VZV glycoprotein. which are expressed on the surface of the infected cells and the virus itself, induce cellular and humoral immunity against VZV after infection. To investigate the molecular basis of viral attenuation, we compared the DNA sequences in the gE,gB, gH,gI,gC, and gL glycoproteins of the Oka vaccine and parental Oka strains. The DNA sequences in gE,gB,gH,gl and gI. of the Oka vaccine strain were completely consistent with those of the parental strain. On the other hand, the Oka vaccine strain containcd 1.76 copies (74 bp) of the tandem repeat sequences within gC, while the parental Oka strain contained 0.76 copies (32 bp), In addition, one silent mutation in the Oka vaccine strain was detected at the stop codon of ORF14 (gC). The difference in DNA sequences of gC between the two strains may related to the attenuated Virulence of the Oka vaccine strain with the skin lesion. (Accepted on August 5, 2000) Kawasaki Igakkaishi 26 (3) : 139 - 146. 2000
