A Carrier State of Mumps Virus in Human Conjunctiva Cells

Abstract

P~ 94(Received for publication, July 13, 1962.) Viral carrier states in cell cultures have been described by several investigators using a variety of virus-cell systems (reviewed in reference 1). Because of techniques applicable to cell cultures, such carrier states would seem to offer particularly good opportunities to gain understanding of interactions of virus and cell that may be important to those naturally occurring infections in which viruses invade and remain in hosts for relatively long periods without causing apparent harm. From the studies already reported, however, it is evident that there is considerable variation in the virus-cell relationships found in carrier systems in vitro. This is to be expected since, at least superficially, the examples of persistent, inapparent viral infections found in man and animals present a diversity of characteristics. Those carrier cultures so far described have, however, usually had several things in common in that they often have utilized cells relatively resistant to the virus; many have required antibody in the medium or have appeared to depend upon some form of interference for protection of the cells; many show evidence for infection of only a small proportion of the cells in the culture. In this and the following paper we shall describe a virus carrier system that is unusual in its combination of features that include (a) lack of any requirement for antibody, (b) indication that there is not a selection of resistant cells, (c) alteration in the cytopathogenicity of the persisting virus, (d) infection of almost all of the cells of the culture, and (e) indication that infected cells are capable of repeated division. Materials and MethodsViruses.--The Dunai strain of mumps virus was isolated from a patient with parotitis (2) by inoculation of throat washings into the amniotie sac of the chick embryo. After the initial amniofic passage, it was cultivated in human conjunctiva cells.

Studies on the Persistent Infection with Measles Virus in HeLa Cells

“…In this sys tem, the maintenance of the carrier state seemed to depend on the ability of the cells releasing infectious virus to replicate and form colonies under the presence of anti measles serum. Similar systems were re ported in the carrier state of measles virus [9,11,12], mumps virus [14,15], rabies virus [2], rubella virus [5,10], arbovirus [7], parainfluenza virus HA2 [3,4,8], parainflu enza virus HVJ [6], and parainfluenza virus SV5 [1]. A unique property of HeLa/MV culture was that only 6 to 18% of cells were releasing infectious virus at any given time though virtually all cells appeared to have been infected.…”

“…Carrier cultures of a non-cytocidal virus such as parainfluenza virus HA2 were cloned in the presence of antibody and all clones clearly contained viral antigen [8]. With mumps virus [15] and rabies virus [2], virus-free clones were obtained at low percentages by cloning with antibody.…”

Mumps Virus-persistently Infected Cell Cultures Release Defective Interfering Virus Particles

“…However, the ultimate role of DIP in 'cell-virus persistence' (Sekellick & Marcus, 1979) is not so clear when a non-cytopathic type of virus persistence takes place (Andzhaparidze et al, 1981 a). Mumps virus, a typical paramyxovirus, can easily establish a carrier state in several cell types (Walker & Hinze, 1962;Truant & Hallum, 1977;McCarthy et al, 1981), but DIP involvement in mumps virus persistence has only recently been documented (McCarthy et al, 1981). These data need confirmation and further extension in order to characterize extracellular mumps DIP.…”

Studies on the Persistent Infection with Measles Virus in HeLa Cells

“…The carrier state established by noncytocidal viruses such as mumps [14], parainfluenza HA2 [5] or rubella virus [11] can be explained as such regulated infections.…”