Chickenpox is usually mild, yet highly contagious disease caused by the virus varicella zoster, a type of herpes virus. IgG and IgM antibodies were detected in all patients with varicella, and IgA in 59 (92%). Virus from vesicles can be isolated in cell culture. The known envelope glycoproteins (gB, gC, gE, gH, gI, gK, gL) correspond with those in HSV, however there is no equivalent of HSV gD. The full deletion of ORF54 likely disrupted essential adjacent genes (ORF53 and ORF55) and therefore could not be complemented on an ORF54-expressing cell line (ARPE54). The rec-RC IgG colocalized with VZV gE on the membranes of VZV-infected cells and neutralized VZV infection in tissue culture. Cross-reaction with herpes simplex antibody was minimal.
Glycoprotein E (gE), a 623 amino acid type I integral membrane protein, is expressed on plasma membranes and in the cytoplasm of VZV infected cells, where it is presumed to be present in the membranes of intracellular vesicles or organelles. VZV gE complexes with gI in the rough endoplasmic reticulum, and most gE exists in the form of gE to gI heterodimers in infected cells. VZV gE is also a predominant component of the virion envelope. The functions of gE, which is encoded by ORF68, are of particular interest because it has been demonstrated that ORF68 is essential for VZV replication. IgA and IgM titres in young adults with zoster were significantly lower than in older patients, and also lower than in young adults with varicella. CSF antibodies to the varicella zoster virus may also be found in varicella zoster virus infections of the nervous system and are more sensitive than PCR in varicella-zoster virus vasculopathy (Nagel et al 2007).