Characterization of glycoprotein C of HSZP strain of herpes simplex virus 1.
Sequences of UL44 genes of strains HSZP, KOS and 17 of herpes simplex virus 1 (HSV-1) were determined and the amino acid sequences of corresponding glycoproteins (gC) were deduced. In comparison with the 17 strain, the HSZP strain showed specific changes in 3 nucleotides and in 2 amino acids (aa 139 and 147, both from Arg to Trp) in the antigenic locus LII. The change at aa 147 was situated within the GAG-binding epitope. In a similar comparison, KOS strain had changes in 3 nucleotides and 3 amino acids (aa 3, 14, and 300). The UL44 genes of HSZP and KOS strains were expressed in insect Sf-21 cells by means of the baculovirus (Bac-to-Bac) expression system. As shown by immunoblot analysis, both the recombinant baculoviruses (B1-HSZP and B6-KOS) expressed a glycosylated gC, the M(r) of which (116 K) was lower than that of gC synthesized in Vero cells (129 K) infected with strains HSZP or KOS. In addition, smaller gC-specific proteins (of apparent M(r) of 50-58 K and 98 K) corresponding to a non-glycosylated precursor polypeptide and/or incomplete forms of the partially glycosylated gC were found. When Balb/c mice were immunized with Sf-21 cells expressing gC, the recombinant gC-HSZP represented a more efficient immunogen possibly due to its stronger expression in these cells. The corresponding gC-HSZP antiserum reacted in enzyme-linked immunosorbent assay (ELISA) equally well with HSZP and KOS virion antigens and neutralized HSZP strain at a low titer. Both gC-HSZP and gC-KOS antisera detected the homologous as well as the heterologous gC antigens in Vero cells regardless whether infected with strains HSZP, KOS or 17, revealing the presence of gC from 6 to 16 hrs post infection (p.i.) in the cytoplasm, on the nuclear membrane and at the cell surface.
Oravcová
I
I
Institute of Virology, Slovak Academy of Sciences, Bratislava, Slovak Republic. viruorav@nic.savba.sk
Kúdelová
M
M
Mlcuchová
J
J
Matis
J
J
Bystrická
M
M
Westra
D F
DF
Welling-Wester
S
S
Rajcáni
J
J
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D016367:Baculoviridae; D001483:Base Sequence; D002460:Cell Line; D002522:Chlorocebus aethiops; D004279:DNA, Viral; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D015870:Gene Expression; D005822:Genetic Vectors; D018259:Herpesvirus 1, Human / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D018411:Spodoptera; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D004279:DNA, Viral; D014759:Viral Envelope Proteins; C038535:glycoprotein gC, herpes simplex virus type 1