Comparison of various macrophage-inhibitory agents on vaginal and systemic herpes simplex virus type 2 infections

Antiviral effect of two aryl-oligopeptides, FR41565 and FR48217

Macrophages from mice pretreated with two chemically synthesized immunostimulating aryl-oligopeptides, FR41565 and FR48217, inhibited the multiplication of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in monkey Vero cells, and that of vesicular stomatitis virus (VSV) in murine L929 cells. In addition, the aryl-oligopeptides protected mice against a lethal HSV-1 infection. In particular, when treated with FR48217 at 6 mg/kg, all mice survived, whereas all control mice died from the HSV-1 infection.

Antimicrobial activity of various immunomodulators: independence from normal levels of circulating monocytes and natural killer cells

The effects of 89Sr treatment on the natural host resistance of CD-1 mice and the enhancement of resistance by immunomodulators to infection with Listeria monocytogenes or herpes simplex virus type 2 (HSV-2) were determined. In the CD-1 mouse, single-dose treatment with 89Sr caused a profound decrease in the number of circulating monocytes (Mo), lymphocytes, and polymorphonuclear leukocytes (PMN) within 1 week. There was also marked functional impairment of the Mo inflammatory response, as well as markedly decreased spontaneous and activatable cytotoxicity by splenic natural killer (NK) cells. Despite this profound cellular suppression, there was no significant change in natural resistance of CD-1 mice to L. monocytogenes or HSV-2 infection. Furthermore, prophylactic treatment of mice with the biologic immunomodulator Corynebacterium parvum or the synthetic immunomodulators maleic anhydride-divinyl ether or avridine in liposomes resulted in comparable enhancement of resistance in 89Sr-treated and normal mice. These data indicate that natural and immunomodulator-enhanced resistance of CD-1 mice to microbial infections do not depend on normal levels of Mo, PMN, or NK cells. The resistance enhancement may rely on activated tissue macrophages (M phi). In contrast to the early changes in circulating leukocytes, the resident peritoneal cell populations were not markedly altered until after day 30. There then was a distinct decline in lymphocytes and a gradual decline in M phi; the change in M phi was apparently due to the lack of an age-related increase in the peritoneal M phi population in 89Sr-treated mice in comparison with a slight increase in resident M phi in normal mice. After CD-1 mice were treated with 89Sr, the number of PMN and the function of NK cells generally recovered by about day 50 and was followed by partial recovery of circulating Mo, unless a second dose of 89Sr was administered.

Contribution of macrophage arginase in the intrinsic restriction of herpes simplex virus replication in permissive macrophage cultures induced by gamma-interferon containing products of activated spleen cells

Cultured peritoneal macrophages (PM) from adult mice of strain DBA/2 (but not C57BL/6) supported productive replication of HSV, as monitored by infectious virus yield and electron microscopy. In contrast, PM of DBA/2 origin, when pretreated with supernatants of Con A-stimulated spleen cells containing immune interferon (IFN-gamma) activity, manifested remarkable intrinsic restriction to HSV replication. The acquisition of this intrinsic restriction to virus replication correlated with the generation of appreciably elevated levels of arginase in supernate of treated PM. Addition of incremental doses of exogenous arginine in the culture medium led to the abrogation of induced restriction to HSV replication in DBA/2 PM, indicating the critical role of arginase in the phenomenon. Furthermore, anti-HSV activity of arginase levels released into the culture medium of IFN containing supernate-treated PM became apparent when assayed on PM, which were precultured in arginine-deficient medium for 24 hours before virus infection and exposure to arginase containing preparation. Taken together, these observations indicate that macrophage arginase can mediate intrinsic restriction to HSV replication in PM.

Alteration of rabbit alveolar and peritoneal macrophage function by herpes simplex virus

Exposure of rabbit alveolar and peritoneal macrophages to infectious herpes simplex virus resulted in inhibition of antibody-dependent cellular cytotoxicity and either enhancement or inhibition of phagocytosis. At all times after exposure, virus was inhibitory to peritoneal macrophage phagocytosis. Alveolar macrophages showed enhanced phagocytic activity in the early stages of virus exposure and inhibition at later time points.

Kinetics and genetics of herpes simplex virus-induced antibody formation in mice

The kinetics of antibody synthesis was investigated after intraperitoneal, subcutaneous, and footpad infection of various strains of mice with herpes simplex virus. Immunoglobulin M antibodies appeared 5 days after and immunoglobulin G antibodies appeared 10 to 12 days after intraperitoneal infection with herpes simplex virus type 1. The major histocompatibility complex and the background genome of inbred mice were not found to have a systematical influence on antibody synthesis. Female mice, however, consistently produced more antibodies than did male if the infection was done intraperitoneally, but not if it was done subcutaneously or into footpads. Castration considerably increased the amount of antibodies produced by male mice. The difference in antibody formation between females and males could be abolished by injection of silica; moreover, antibody titers were enhanced by this treatment. This has also been found by immunization with a Formalin-inactivated herpes simplex virus vaccine. The effect of silica in enhancing antibody formation could be observed up to 12 days after infection. Infectious virus could be detected up to 2 days after infection, and herpes simplex virus type 1 antibody-stimulating antigens could be detected up to 4 days in ultrasonicates of macrophages. The assumption is made that androgen-sensitive cell populations, including macrophages and their soluble products, are involved in antibody-depressing mechanisms.

Suppression of tuberculoimmunity in mice by Evans blue dye

Evans blue dye, which acts as an adjuvant in mice to promote induction of cell-mediated immunity, was found earlier to apparently act contrarily and decrease tuberculoimmunity. This phenomenon was investigated here in a long-term experiment examining the persistence of the suppressed immunity. Systemic suppression after injection of only 1 mg of dye was confirmed and was found to last for more than 2 weeks but less than 11 weeks. Localized evidence for dye-caused depression of tuberculoimmunity also was seen by the development in dye-injected mice immunized with emulsified whole bacilli of caseating tubercles at sites of pulmonary infection, a very rare type of pathology for tuberculosis in mice. The experiment, in addition, detected an aging-related decline in mice of resistance to tuberculosis evident by shortened survival, enlarged pulmonary tubercles, and increased susceptibility to systemic tuberculin reaction.

Inhibition of herpes simplex virus multiplication by activated macrophages: a role for arginase?

Proteose-peptone-activated mouse macrophages can prevent productive infection by herpes simplex virus in neighboring cells in vitro whether or not those cells belong to the same animal species. The effect does not require contact between the macrophages and the infected cells, may be prevented by adding extra arginine to the medium, and may be reversed when extra arginine is added 24 h after the macrophages. Arginase activity was found both intracellularly and released from the macrophages. The extracellular enzyme is quite stable; 64% activity was found after 48 h of incubation at 37 degrees C in tissue culture medium. No evidence was found that the inefficiency of virus replication in macrophages was due to self-starvation by arginase. As might be predicted macrophages can, by the same mechanism, limit productive infection by vaccinia virus.

Permissiveness of rabbit monocytes and macrophages for herpes simplex virus type 1

The permissiveness of rabbit monocytes and macrophages for herpes simplex virus was examined. Peripheral blood monocytes, alveolar macrophages, and peritoneal exudate macrophages were studied for their ability to replicate herpes simplex virus strains RE and KOS. Results indicated different degrees of interaction with virus depending on the macrophage type. Only peritoneal exudate macrophages showed evidence of virus replication. Productive infection was limited, with only a small number of cells (0.02%) yielding infectious virus. Higher numbers of cells appeared to be abortively infected. Approximately 40% expressed antigens, whereas virtually all were killed by exposure to virus. Coreless particles were seen by electron microscopy in about one-third. Alveolar macrophages were also killed by virus and showed evidence of virus adsorption, but showed no indication of productive or abortive infection. Monocytes neither adsorbed nor replicated virus, and viability was unaffected. Results suggest that differences in degrees of cellular maturation or differentiation, or both, account for the spectrum of interactions seen between herpes simplex virus and rabbit macrophages.

Lymphocyte-derived chemotactic factor synthesis in initial genital herpesvirus infection: correlation with lymphocyte transformation

Lymphocyte transformation and production of lymphocyte-derived chemotactic factor in response to herpes simplex virus antigen were studied in 15 patients with initial genital herpes and 10 controls. The patients underwent frequent genital examinations, viral cultures, and weekly immunological studies for a period of 11 weeks. The production of lymphocyte-derived chemotactic factor was maximal in week 1 of the disease and declined to control levels by week 6. In contrast, lymphocyte transformation was lowest in week 1, reached a maximum by week 4, and declined to control levels by week 11. Production of lymphocyte-derived chemotactic factor in week 1 was significantly lower in nine patients who developed signs or symptoms of systemic herpes infection than in six who had localized disease. In addition, a marked but transient decline in the production of this lymphokine was observed in patients at the time of clinical recurrence. Virus-specific lymphocyte transformation correlated inversely with the duration of genital pain and lesions and did not correlate with the presence of systemic signs or symptoms. These findings indicate that during initial genital herpes infection the dynamics of lymphocyte transformation and those of lymphocyte-derived chemotactic factor production are different, and that the generation of this lymphokine is an early component of the cellular immune response in this disease. Furthermore, adequate produce of lymphocyte-derived chemotactic factor may be important in restricting herpes simplex virus to the genital area and preventing disease recurrence.

Infections of susceptible and resistant mouse strains with herpes simplex virus type 1 and 2

The spread of HSV of type 1 and 2 was investigated after intraperitoneal, intraplantar and intracerebral infections of resistant (C57/bl) and susceptible (NMRI) mice. The virus spreads after i.p. infection to the spleen and the liver to the same extent in both strains of mice. However, virus is eliminated earlier in resistant mice. Intracerebral infections revealed a peculiar type of resistance of C57/bl mice especially for type 2 of HSV. HSV multiplies in the thymus at the early stage of infection and can be detected in this organ in sick mice of NMRI strain. HSV-1 and 2 can be detected in the spinal cord of C57/bl mice without sickness or death of these animals.