Typing of Herpes Simplex Virus Strains of Genital and Nongenital Origins

Abstract

Herpes simplex virus strains isolated from genital and nongenital sites were classified into type 1 (HSV-1) and type 2 (HSV-2) by endpoint neutralization tests using IgM of rabbits hyperimmunized with either HF (HSV-1) or UW-268 (HSV-2) strain. It was found that about one-third of the genital isolates belonged to type 1, in contrast to the general concept that HSV-2 represents genital herpes strains. These HSV-1 strains, differing from HSV-2, were mostly isolates from acute herpetic lesions of female patients with constitutional symptoms. On the other hand, all nongenital isolates except one were determined to be HSV-1. There was no intermediate type equally neutralizable by both types of IgM. A majority of the HSV-2 strains produced large plaques in chick embryo (CE) cells before passage through avian cells. In contrast, all HSV-1 strains failed to produce such large CE plaques even after serial passages through avian hosts.Herpes simplex virus (HSV) can be classified into two distinct types, HSV-1 and HSV-2, on the basis of antigenical analyses [2,6,8,9,15]. The correlation between the type and the site of isolation adds importance from the clinical and epidemiological viewpoints. It has been documented that HSV-1 is isolated mainly from nongenital and HSV-2 from genital lesions. For the latter, a mode of venereal transmission has been implied [9]. It was further suggested that HSV-2 might be associated with uterine cervical cancer [11][12][13].The primary purpose of the present study was to determine whether and how frequently HSV-2 could be isolated from genital herpes infections, notably of females, in this country. As the criterion on which to determine the types, Hampar et al's neutralization technique using type-specific hyperimmune rabbit IgM and complement [4] was employed.An additional purpose was to find a simple method for type determination as a substitute for the cumbersome serological procedure. The chick embryo (CE) cell plaque marker of Figueroa and Rawls [3] and Lowry et al [7] was thought suitable for this purpose, and all the isolates were tested for their ability to form plaques in CE cells. Results of these experiments are described in this communication. MATERIALS AND METHODSViruses. Specimens for virus isolation were collected in the gynecological ward of the University of Tokyo Hospital, Tokyo, the National Cancer Center Hospital, Tokyo, and the Department of Dermatology of Toranomon Hospital, Tokyo, by applying swabs to lesions, which were immediately rinsed in a maintenance medium containing appropriate concentrations of penicillin and streptomycin. The rinse was inoculated into Vero cell cultures. The maintenance medium used was Eagle's minimum essential medium (MEM) supplemented with 2% calf serum. In cases that typical cytopathic effects were noted the culture fluid was harvested and Requests for reprints should be addressed to Dr.

Estimation of Type‐Specific Neutralizing Antibody to Herpes Simplex Virus Type 2 in Uterine Cervical Cancer Patients by a New Absorption Method

“…The HF strain of HSV-1 and the UW-268 strain of HSV-2 (34), which had been maintained by passage through Vero cells were used. Virus infectivity was expressed by the tissue-culture-infective dose (TCD) as determined by the microtitration method described earlier (14). For immunization of animals, culture fluids of infected HeLa cells were used.…”

Differentiation of Herpes Simplex Virus Types 1 and 2 by Plaque Appearances on Semicontinuous Rabbit Lens Epithelial Cells in the Clinical Laboratory

“…Difference in plaque-forming ability or plaque appearance between herpes simplex virus type 1 (HSV1) and type 2 (HSV2) had been studied in various cell culture systems1, 2,7,12,13,15), and are considered to be a biological marker distinguishing one from the other. Especially, primary chick emblryonic fibroblasts (CEF) are known to have unique characteristics for identifing HSV1 and HSV2.…”

“…Most HSV1 isolates produce no plaques or small plaques on CEF. In contrast, large plaques are formed on CEF by HSV2 strains from the first passage of the virus2, 7,12). CEF culture systems accompanied by other kinds of cell cultures were used to distinguish HSV1 from HSV2 in a clinical laboratory14) or to select temperature-sensitive mutants for the study of pathogenicity in guinea pigsl).…”

Plaque Morphology of Herpes Simplex Virus in Various Cells under Liquid Overlay as a Marker for Its Type Differentiation

“…However, most of the criteria thus far reported on which to differentiate the two types have been based on quantitative rather than qualitative differences, except the presence of tubular structures in type 2 herpes simplex virus (HSV-2)-infected cells [1] and density of viral DNA [3,6]. We have searched for a simple routine procedure to determine the types of HSV isolates and found that the chick embryo (CE) cell plaque marker [2,8] was suited for this purpose [5]. Yet this marker also measured a quantitative difference and showed a disadvantage that a strain experiencing serial egg or CE cell passages might possibly be mistyped.…”

“…Type determination of these isolates was based on neutralization by specific hyperimmune rabbit IgM in the presence of complement [4]. Passage histories of the strains were detailed elsewhere [5]. Virus stocks were prepared in Vero cells, the culture fluids being shell-frozen in glass ampoules and stored at -70 C.…”