Herpesvirus ateles, a New Lymphoma Virus of Monkeys

Abstract

A NEW herpesvirus, designated Herpesvirus ateles, has been isolated from a spider monkey (Ateles geofroyii) primary kidney culture. The culture was prepared from a mature male spider monkey (810–69) imported from Guatemala and housed in our laboratory for 12 months. The cell layer was obtained from the renal cortex by trypsinization using standard procedures. Growth medium was Eagle's minimum essential medium with 10% calf serum plus antibiotics. A well grown cell layer developed in 6–8 days. On day 11 the cell layer presented a large number of bizarre cells and polykaryocytes. On day 16 the cell layer was scraped and together with the culture fluid was collected as isolate No. 810 (H. ateles) and stored at 4° C, −86°C, and −176°C. H. ateles strain No. 810 had a titre of 10⁴ TCID₅₀/ml. in squirrel monkey foetal lung cell line No. 241, 10^4.5 TCID₅₀/ml. in owl monkey kidney cell line No. 210, 10^3.5 TCID₅₀/ml. in human embryonic lung cell line and 10^5.0 TCID₅₀/ml. in rabbit kidney cell line at 14, 17, 23, and 30 days, respectively, after inoculation. All cell lines were prepared in our laboratory. The cytopathic effect was characterized by scattered foci of swollen and rounded cells, polykaryocytes and intranuclear inclusion bodies. The classical Cowdry type A inclusion body was observed in owl monkey kidney cultures. In human foetal lung, squirrel monkey kidney and rabbit kidney cell lines the inclusion bodies were small, measuring approximately 1 µm in diameter. The virus was inactivated by ether and heat (56° for 30 min) and inhibited by bromodeoxyuridine. The size was determined to be between 100 nm and 220 nm by filtration. Ultrastructural studies of infected tissue culture cells revealed typical herpesvirus particles (Fig. 1). These physical, chemical and morphological characteristics of the isolate place it in the herpesvirus group. Antisera to H. simplex, Herpes T., infectious bovine rhino tracheitis, sand rat nuclear inclusion agent, H. suis, ground squirrel agent, H. saimiri, spider monkey herpesvirus, and H. aotus failed to neutralize the infectivity of H. ateles^1,2. Fluorescent antibody studies have also demonstrated that H. ateles is distinguishable from H. saimiri, OMKI 68–69, Herpes T. and H. simplex³. These data support the conclusion that H. ateles is a distinct member of the herpesvirus group.