Specificity of the Immune Response of Mice to Herpes Simplex Virus Glycoproteins B and D Constitutively Expressed on L Cell Lines

Abstract

SUMMARYMouse L cell lines have been developed which constitutively express glycoproteins B (gB) and D (gD) of herpes simplex virus type 1. When used to study the immune response of mice to the viral glycoproteins, it was found that both gB and gD induce a delayed type hypersensitivity response and both also induce an antibody response, but only the cell line expressing gD could stimulate the production of neutralizing antibody. Virus-specific cytotoxic T lymphocytes (CTLs) recognized gB expressed by the cell line and this line could also induce CTLs in mice. Recognition of gD by major histocompatibility complex class I restricted CTLs was never seen. Vaccination of mice with the cell lines provided protection from viral challenge and inhibited the establishment of a latent infection, although gD proved to be the better protective immunogen. INTRODUCTIONThe immune response of mice to herpes simplex virus type 1 (HSV-1) is known to involve both antibody and cell-mediated protective mechanisms. In particular, T lymphocytes are considered to play a central role in the recovery from a primary infection (for review, see Nash et al., 1985). However, the particular proteins of the virus recognized by these cells are far from clear. Experiments to date have centred on the use of the virus mutants deficient in the expression of certain glycoproteins to study the nature of the antigens recognized by cytotoxic T lymphocytes (CTLs) (Carter et al., 1981;Lawman et al., 1980;Glorioso et al., 1985), and the affinity purification of glycoproteins from whole virus preparations for use as immunogens to study delayed type hypersensitivity (DTH) responses (Schrier et al., 1983;Chan et al., 1985).The main problem has been how to separate the various antigens of this complex virus in order to dissect the nature of the immune response. Our approach has been to investigate the immune response to individual glycoproteins of HSV-1 by expressing the appropriate genes in mouse L cells. In this system, the glycoproteins are expressed in isolation but are still presented at the cell surface analogous to infected cells. Our reason for choosing glycoproteins is that they are likely to represent major target antigens of the immune system: this is true for the antibody response (for review, see Norrild, 1985) and there is evidence to suggest that glycoproteins are the major targets for both major histocompatibility complex (MHC) class I and class II restricted T lymphocytes (Carter et al., 1981 ;Lawman et al., 1980;Glorioso et al., 1985;Schrier et al., 1983).In this paper we report the establishment of L cells expressing either glycoprotein B (gB) or D (gD) and the use of these lines to study the specificity of the T cell response to HSV-1. The lines were also used to immunize mice against primary virus infections and to prevent the establishment of latent infections.

Cytotoxic T lymphocytes specific for herpes simplex virus (HSV) studied using adenovirus vectors expressing HSV glycoproteins

“…Our results using transfected cells suggested that primary H-2k-restricted anti-HSV CTLs recognized syngeneic target cells expressing low levels of glycoprotein C (gC), but not cells expressing gB, gD or gE (Rosenthal et al, 1987). These conclusions were partly supported by similar observations involving an H-2 k cell line transfected with the HSV-1 gB gene that was lysed, albeit poorly, by restimulated anti-HSV CTLs and a cell line expressing gD that was not lysed (Blacklaws et al, 1987).…”

“…Using these primary CTLs, which often lyse HSV-infected target ceils less efficiently than restimulated CTLs, we were unable to detect lysis of transfected H-2 k cells expressing gB or of H-2 k cells infected with AdgB2. Blacklaws et al (1987) observed low but significant levels of HSV-specific CTL lysis of an H-2 k cell transformant expressing gB. However, they and others have stimulated CTL activity by culturing spleen cells in the presence of viral antigen (Blacklaws et al, 1987;Martin et al, 1987), which could potentially lead to selective expansion of CTL clones, especially those directed at structural polypeptides.…”

“…Early studies, partly based on the assumption that cell surface molecules would act as T cell target antigens, suggested that HSV glycoproteins were major CTL targets (Lawman et al, 1980;Carter et al, 1981 ;Glorioso et al, 1985). Subsequent studies involving transfected cells have partially borne out this conclusion (Blacklaws et al, 1987;Rosenthal et al, 1987).…”

Induction of protective immunity with antibody to herpes simplex virus type 1 glycoprotein H (gH) and analysis of the immune response to gH expressed in recombinant vaccinia virus

“…Since it remains impossible to synthesize gH in an authentic antigenic form in the absence of other HSV proteins, direct and reliable measurement of anti-gH antibodies cannot be achieved. The neutralizing and anti-fusion properties of gHspecific antibodies are similar to those of some antibodies against gD Gompels & Minson, 1986;Noble et al, 1983), an antigen that has long been recognized as providing protective immunity in experimental animals both by active and passive immunization (Long et al, 1984;Cremer et al, 1985;Berman et al, 1985;Blacklaws et al, 1987;Krishna et al, 1989;Balachandran et al, 1982;Simmons & Nash, 1985). By analogy we might expect gH to be protective and we have demonstrated that LPI 1, a MAb specific for HSV-1 gH, provides efficient protection against zosteriform spread of HSV-1 in the mouse.…”

Mucosal and systemic antiviral antibodies in mice inoculated intravaginally with herpes simplex virus type 2

“…In the present studies, IVAG inoculation and challenge withHSV-2 elicited similar antibody responses to virus-encoded glycoproteins in both sera and vaginal washings. Glycoproteins gB, gC and gD are known to induce .neutralizing -and complement-dependent ~cyto-lyric antibodies (Balachandran et al, 1982b;Corey & Spear, 1986;Rawls, 1985;Spear, 1984) whereas gB and gC also elicit delayed hypersensitivity responses (Corey & Spear, 1986;Rawls, 1985) and act as recognition elements for major histocompatibility complex class Irestricted CTLs (Blacklaws et al, 1987;Corey & Spear, 1986;Rawls, 1985;Rosenthal et al, 1987). These findings indicate that the mechanisms responsible for the stimulation of antiviral humoral immunity are similar at systemic and mucosal sites and that analogous recognition of viral antigens at distant mucosal sites might be expected.…”