Biomedical subjects

R N Lausch

Publications and source records attributed to R N Lausch.

At least 37 records · Page 2Linked to original sources

PubMed1995

Differences in interleukin-6 gene expression between cultured human corneal epithelial cells and keratocytes.

PURPOSE: To determine whether interleukin-6 (IL-6) can be synthesized by human corneal keratocytes and epithelial cells. METHODS: Epithelial cells and keratocytes isolated from the same donor corneas were grown in vitro. After 2 to 3 passages, the cultures were exposed to varying concentrations of recombinant human interleukin-1 (IL-1 alpha) or tumor necrosis factor (TNF-alpha). Culture supernatants subsequently underwent enzyme-linked immunosorbent assays for cytokine content. The levels of cytokine mRNA in cell lysates were monitored by the reverse transcription-polymerase chain reaction. RESULTS: Cultured human keratocytes stimulated with 100 U/ml IL-1 alpha for 18 hours produced more than 160 ng IL-6 per 10(6) cells. Under the same conditions 500 U/ml TNF-alpha induced approximately 5 ng IL-6. IL-6 mRNA, evident by 3 hours after exposure to either cytokine, accumulated and persisted through 18 hours. Exposure of epithelial cells to IL-1 alpha or TNF-alpha induced minimal and transient expression of IL-6 mRNA and < 0.5 ng protein product per 10(6) cells. The poor production of IL-6 did not reflect an inability of epithelial cells to respond to IL-1 alpha and TNF-alpha because both cytokines induced these cells to make copious amounts of IL-8. CONCLUSIONS: These results demonstrate that both IL-1 alpha and TNF-alpha could induce keratocytes to produce nanogram levels of IL-6 but IL-1 alpha was a 30-fold more effective inducer. In contrast, neither cytokine could stimulate epithelial cells to make more than picogram quantities of IL-6. The abundant IL-6 synthesized by keratocytes may promote various activities including specific immune responses in surrounding lymphoid tissues.

Base Sequence↗

PubMed1994

Interleukin-10 treatment can suppress stromal keratitis induced by herpes simplex virus type 1.

Herpes simplex virus type 1 (HSV-1) infection of the murine cornea induces an intense inflammatory response that can lead to permanent blindness. We tested whether IL-10, a cytokine that has anti-inflammatory properties, could suppress the development of stromal disease. Murine rIL-10 was inoculated intracorneally 4 before and again on days +2 and +5 relative to the time of topical HSV-1 corneal infection. Additionally, the mice received IL-10 i.p. at the time of virus administration and again 3 days post-infection. Four weeks post-infection, the incidence of blinding disease was 95% in the saline-treated controls but only 36% in the IL-10-treated animals. Histologic studies showed extensive cellular infiltrates in control corneas but not in those of the IL-10-treated eyes. Examination of the proinflammatory cytokine levels in the cornea 10 days after infection revealed that the presence of IL-2 was 10-fold lower and IL-6 some 50-fold lower than that found in the controls. IL-1 alpha levels were not reduced. The IL-10 treatment protocol employed did not suppress the systemic cellular or humoral immune responses to viral Ag, nor was the rate of HSV-1 clearance from the eye different from that seen in the controls. In vitro studies revealed that spontaneous production of IL-6 by excised normal corneas was inhibited by > 95% with low dose IL-10. IL-1 alpha synthesis was not inhibited. Collectively, these results indicate that IL-10 treatment can 1) suppress the production of certain cytokines produced by corneal cells, and 2) minimize ocular inflammation without compromising clearance of the infecting virus from the eye.

Animals↗

PubMed1994

Differential regulation of granulocyte-macrophage colony-stimulating factor gene expression in human corneal cells by pro-inflammatory cytokines.

Neutrophils and Langerhans cells participate in inflammatory reactions within the human cornea. Because granulocyte-macrophage (GM)-CSF is a chemotactic and activating factor for these two cell types, we investigated whether this cytokine is produced by human corneal epithelial cells and corneal fibroblasts. Cultures of each cell type were exposed to increasing concentrations of IL-1 alpha or TNF-alpha. Culture supernatants were assayed for GM-CSF by using ELISA and cytokine mRNA levels were monitored by using reverse transcriptase-PCR. IL-1 alpha treatment of both cell types resulted in the appearance of GM-CSF mRNA and the production of > 480 pg protein/10(6) cells. However, TNF-alpha treatment yielded divergent results. Stimulation of epithelial cells with TNF-alpha resulted in the appearance of > 560 GM-CSF mRNA molecules per cell and production of > 1300 pg GM-CSF/10(6) cells. In contrast, stimulation of corneal fibroblasts resulted in < 16 GM-CSF mRNA molecules/cell and < 60 pg GM-CSF/10(6) cells. Binding studies with 125I-labeled TNF-alpha revealed that corneal fibroblasts had as many receptor sites as did corneal epithelial cells. Furthermore, corneal fibroblasts could respond to TNF-alpha-receptor-mediated signal transduction because they produced nanogram amounts of IL-6 after being treated with this cytokine. The results suggest that both cell types synthesize GM-CSF in response to IL-1 alpha, but that only corneal epithelial cells produce significant amounts of GM-CSF after TNF-alpha exposure. Differences in the responses of the two cell types to TNF-alpha may reflect a means of limiting accumulation of neutrophils and Langerhans cells and, thus, minimize corneal damage.

Base Sequence↗

PubMed1994

Synergistic anti-herpes effect of TNF-alpha and IFN-gamma in human corneal epithelial cells compared with that in corneal fibroblasts.

In this study we compared how effectively the proinflammatory cytokines TNF-alpha and IFN-gamma could inhibit HSV-1 replication in human corneal tissue fragments and monolayers of epithelial cells and fibroblasts derived from intact corneas, and investigated the mechanism responsible for the inhibition. Pretreatment of corneal tissue or cells derived therefrom with TNF-alpha (50 U/ml) and IFN-gamma (5 IU/ml) consistently induced a synergistic antiviral effect. Inhibition of HSV-1 growth was most evident in fibroblasts (> 1000-fold reduction) and less apparent (7-25-fold reduction) when epithelial cells were the target. Virus suppression was correlated with the induction of IFN-beta because antibody to this cytokine but not IFN-alpha abrogated synergism. The more modest synergistic effect in epithelial cells was associated with a > or = 4-fold reduction in the synthesis of IFN-beta protein and mRNA, and decreased responsiveness of these cells to the antiviral effect of IFN-beta. We conclude that the combination of TNF-alpha and IFN-gamma induces a synergistic antiviral effect in corneal cells. The degree of synergism observed varies with the corneal cell type, and is correlated with the amount of IFN-beta induced and the target cell responsiveness to the antiviral action of this cytokine.

Animals↗

PubMed1993

Cytokine expression in vivo during murine herpetic stromal keratitis. Effect of protective antibody therapy.

HSV-1 topical infection on the murine cornea can induce herpetic stromal keratitis (HSK), a T cell-mediated inflammatory response that results in blindness. To begin to decipher the molecular interactions involved in this infection, extracts of infected corneas were assayed for the presence of seven different cytokines by ELISA. The most prominent cytokines detected were IL-1 alpha and IL-6. Both were elevated by day 2 after infection, reached peak levels of 82 and 538 pg/cornea, respectively, at day 10, and then diminished over the next 10 days. In contrast, TNF-alpha concentrations were not elevated over that seen in uninfected corneas at any time during the 20-day observation period. IFN-gamma and granulocyte-macrophage CSF corneal concentrations were below the sensitivity of the assay. We investigated whether passive transfer of antibody to viral glycoprotein D, which prevents HSK, influenced the production of IL-1 alpha and IL-6. It was found that corneal concentrations of IL-1 alpha were reduced threefold and IL-6 was undetectable at day 10 in the antibody-treated hosts. The levels of IL-10 and IL-4 in uninfected control and antibody-treated hosts were also monitored. Neither of these two regulatory cytokines was associated with HSK development or effective antibody therapy. Naive corneas cultured in vitro spontaneously produced IL-1 and IL-6, indicating that cells resident in the cornea had the ability to synthesize these proinflammatory cytokines. Collectively, our results imply that IL-1 alpha and IL-6 may be important contributors to the development of HSK pathogenesis.

Animals↗

PubMed1993

Synergistic anti-HSV effect of tumor necrosis factor alpha and interferon gamma in human corneal fibroblasts is associated with interferon beta induction.

HSV-1 (17) replicated to high titer in human corneal fibroblasts (> 10(8) PFU/10(5) cells) following infection at one PFU per 100 cells. Pretreatment of the cells for 24 h with 50 U/ml recombinant human tumor necrosis factor alpha (TNF-alpha) or 5 IU/ml of human interferon gamma (IFN-gamma) resulted in only modest reduction (2- to 19-fold) in virus yield. However, when the two cytokines were combined the antiviral effect was dramatically increased. There was > 1000-fold reduction in virus titer in 8 of 8 trials. In contrast, the combinations of 50 U/ml TNF-alpha with 5 IU/ml IFN-alpha or IFN-beta did not produce a synergistic effect. The pronounced synergistic antiviral activity of TNF-alpha+IFN-gamma could be demonstrated in fibroblast cultures from different donors, and HSV-2 as well as HSV-1 strains were inhibited. There was no evidence that dual cytokine treatment was toxic for uninfected or HSV-infected cells. Insight into the mechanism responsible for the synergistic effect was provided by the observation that TNF-alpha+IFN-gamma induced IFN-beta. In addition, anti-IFN-beta but not anti-IFN-alpha antibodies could reverse the antiviral effect, and reconstitution with IFN-beta could duplicate the phenomenon. We conclude that the combination of TNF-alpha and IFN-gamma at low concentrations can exert a powerful anti-herpes effect in human corneal fibroblasts which can be chiefly attributed to the induction of IFN-beta.

Antiviral Agents↗

PubMed1993

Mapping the genetic region coding for herpes simplex virus resistance to mouse interferon alpha/beta.

Herpes simplex virus (HSV) ocular virulence has been associated with strain sensitivity to mouse interferon (IFN)-alpha/beta. To identify the region of the virus genome associated with heightened resistance to this cytokine, intertypic recombinants were constructed using the intact genome of avirulent, IFN-sensitive HSV type 1 (strain 35) and XbaI-digested DNA from virulent, IFN-resistant HSV type 2 (strain 186). An intertypic recombinant, designated HSV-R4, was isolated which grew to titres 10- to 100-fold higher than HSV-1(35) in mouse ocular tissue in vivo, and induced stromal keratitis. The recombinant which was several orders of magnitude more resistant to mouse IFN-alpha/beta than HSV-1(35) had a genome composed of HSV-1(35) DNA except for a 12 kb fragment (0.15 to 0.23 map units) derived from HSV-2(186). To define the IFN resistance locus further, three overlapping subclones of this 12 kb fragment were constructed from the HSV-2(186) genome and subjected to marker rescue experiments. The cloned BamHI D fragment was the only subclone that promoted HSV-1(35) ocular growth in vivo. An intertypic recombinant, designated HSV-R(BD), was isolated from the 35 x 186 BamHI D transfection progeny pool. This recombinant, in contrast to HSV-1(35), was several orders of magnitude more resistant to mouse IFN-alpha/beta inhibition in vitro, grew 10- to 100-fold better in mouse ocular tissue in vivo, and caused severe necrotizing stromal keratitis in BALB/c mice. Analysis of the recombinant genome indicated that the HSV-2 genetic information responsible for IFN resistance of HSV-R(BD) was located within the BamHI D fragment, most likely mapping to that region containing three partial open reading frames designated UL14, UL15 and UL16. The products encoded by this region remain to be identified.

Animals↗

PubMed1993

Induction of interleukin-8 gene expression is associated with herpes simplex virus infection of human corneal keratocytes but not human corneal epithelial cells.

Interleukin-8 (IL-8) is a proinflammatory cytokine released at sites of tissue damage by various cell types. One important function of IL-8 is to recruit neutrophils into sites of inflammation and to activate their biological activity. Stromal keratitis induced by herpes simplex virus type 1 (HSV-1) is characterized by an initial infiltration of neutrophils. This study was carried out to determine whether cells resident in the cornea synthesize IL-8 after virus infection. Pure cultures of epithelial cells and keratocytes established from human corneas were infected with HSV-1, and the medium overlying the cells was subsequently assayed for IL-8 by an enzyme-linked immunosorbent assay. Cytokine mRNA levels in cell lysates were monitored by Northern (RNA) blot analysis. It was found that virus infection of keratocyte cultures led to the synthesis of IL-8-specific mRNA with more than 30 ng of IL-8 made per 10(6) cells. Neither UV-inactivated virus nor virus-free filtrates collected from HSV-1-infected keratocytes could induce IL-8 protein or mRNA, suggesting that viral gene expression was needed for induction of IL-8 gene expression. Unlike keratocytes, HSV-1-infected epithelial cells failed to synthesize IL-8 protein or mRNA. However, these cells readily produced both molecules following tumor necrosis factor alpha stimulation. HSV-1 had similar titers in both cell types. Thus, the failure to induce IL-8 synthesis was not due to an inability of the virus to replicate in epithelial cells. The capacity of HSV-1-infected corneal keratocytes to synthesize IL-8 suggests that these cells can contribute to the induction of the acute inflammatory response seen in herpes stromal keratitis.

Cell Division↗

PubMed1993

IL-8 gene expression in cultures of human corneal epithelial cells and keratocytes.

PURPOSE: To determine if human corneal keratocytes and epithelial cells synthesize and release IL-8 after stimulation with selected proinflammatory cytokines. METHODS: Human corneal keratocytes and epithelial cells were isolated from human corneal buttons and grown independently in vitro. Epithelial cell cultures stained positive in immunofluorescent tests with antibody specific for keratin (AE1/AE3), whereas keratocyte cultures were unreactive. Both cell types reacted with anti-vimentin antibody. Cultures of the two cell types were treated with various concentrations of human recombinant interleukin-1 alpha or TNF-alpha. Culture supernatants were then assayed at timed intervals by enzyme-linked immunosorbent assay for IL-8 content. Cytokine mRNA levels in cell lysates were monitored by Northern blot analysis. RESULTS: Exposure of corneal keratocytes and epithelial cells to either interleukin-1 alpha or TNF-alpha stimulated IL-8 mRNA synthesis and IL-8 production in a dose-response fashion. It was also found that TNF-alpha stimulated the synthesis of comparable amounts of IL-8 in both cell types. However, when IL-8 synthesis between the two cell types was compared after interleukin-1 alpha stimulation it was found that keratocytes synthesized 33 times more IL-8 than did epithelial cells. CONCLUSIONS: The results establish that pro-inflammatory cytokines can induce IL-8 synthesis in both human corneal epithelial cells and human corneal keratocytes. They also suggest that interleukin-1 alpha may play a more active role in amplifying inflammatory responses in the stroma than in the epithelial layer of the cornea.

Blotting, Northern↗

PubMed1993

Passive transfer of anti-herpes simplex virus type 2 monoclonal and polyclonal antibodies protect against herpes simplex virus type 1-induced but not herpes simplex virus type 2-induced stromal keratitis.

PURPOSE: To investigate whether passive transfer of antibodies to viral glycoproteins would protect against herpes simplex virus type 2-induced stromal keratitis. METHODS: Balb/c mice were infected on the scarified cornea with herpes simplex virus types 1 or 2 (HSV-1 and HSV-2, respectively), and monoclonal or polyclonal antibodies were administered intraperitoneally 24 hr later. Eyes were monitored for corneal opacity. Flow cytometry was used to examine the expression of glycoproteins on the surface of HSV-infected cells. RESULTS: Passive transfer of monoclonal antibodies to viral glycoproteins gB, gD, or gE or anti-HSV-2 hyperimmune serum were all highly effective (P < 0.005) at preventing blinding disease induced by HSV-1. In contrast, none of the antibody preparations could prevent stromal keratitis when the animals were challenged with various HSV-2 strains. However, antibody treatment could prevent the development of fatal encephalitis in the majority of HSV-2 infected hosts. Flow cytometry analysis revealed that gD and gB expression on the membranes of HSV-2 infected corneal epithelial cells isolated from excised corneas was substantially less (P < 0.005) than that detected on HSV-1 infected cells at both 24 and 48 hours postinfection. This antigenic difference was not due to the failure of HSV-2 to replicate in corneal epithelial cells in vivo. CONCLUSIONS: Decreased levels of membrane glycoprotein antigen expression may be one factor contributing to the refractiveness of HSV-2-induced ocular disease to humoral immunotherapy.

Animals↗

PubMed1991

Anti-glycoprotein D monoclonal antibody protects against herpes simplex virus type 1-induced diseases in mice functionally depleted of selected T-cell subsets or asialo GM1+ cells.

Passive transfer of a monoclonal antibody (MAb) specific for glycoprotein D (gD) is highly effective in preventing the development of herpes simplex virus type 1-induced stromal keratitis. In the present study, we investigated whether animals which had been functionally depleted of T-cell subsets or asialo GM1+ cells would continue to be responsive to MAb therapy. BALB/c mice were depleted of CD4+, CD8+, or asialo GM1+ cells by treatment with anti-L3T4, anti-Lyt 2.2, or anti-asialo GM1 antibodies, respectively. Functional depletion of CD4+ cells was documented by the loss of delayed-type hypersensitivity responsiveness, while CD8+ cell depletion was accompanied by abrogation of cytotoxic lymphocyte activity. Anti-asialo GM1 treatment led to the loss of natural killer cell lytic activity. Mice depleted of the desired cell population and infected on the scarified cornea with herpes simplex virus type 1 uniformly developed necrotizing stromal keratitis by 3 weeks postinfection. A single inoculation of anti-gD MAb (55 micrograms) given intraperitoneally 24 h postinfection strongly protected hosts depleted of CD4+ cells against stromal keratitis. Likewise, antibody treatment in CD8+ or asialo GM1+ cell-depleted hosts was as therapeutically effective as that seen in non-cell-depleted mice. We also observed that in cell-depleted mice, the virus spread into the central nervous system and caused encephalitis. The CD4+ cell-depleted mice were the most severely affected, as 100% developed fatal disease. Anti-gD MAb treatment successfully protected all (32 of 32) CD4+-, CD8+-, or asialo GM1(+)-depleted hosts against encephalitis. We therefore conclude that antibody-mediated prevention of stromal keratitis and encephalitis does not require the obligatory participation of CD4+, CD8+, or asialo GM1+ cells. However, when mice were simultaneously depleted of both CD4+ and CD8+ T-cell subsets, antibody treatment could not prevent fatal encephalitis. Thus, antibody can compensate for the functional loss of one but not two T-lymphocyte subpopulations.

Animals↗

PubMed1991

Differences in the capacity of two herpes simplex virus isolates to spread from eye to brain map to 1610 base pairs of DNA found in the gene for DNA polymerase.

A intertypic recombinant, designated HSV-R(D1), had previously been generated from non-neuroinvasive HSV-2(186) and neuroinvasive HSV-1(17). Although the recombinant contained less than 2% of the HSV-1 genome, it retained the neuroinvasive phenotype. The nucleotide sequences responsible for the neuroinvasiveness of HSV-R(D1) were previously mapped to a 3.0 kb segment of DNA located within the DNA polymerase gene (mu 0.414 to 0.430) via marker rescue experiments. We have now sequenced this region and compared our results to the published nucleotide sequence of the HSV-1(17) and HSV-2(186) DNA polymerase genes. It was found that the 3.0 kb HSV-R(D1) DNA fragment consisted entirely of HSV-2(186) nucleotide sequences except for the presence of 1610 bp of HSV-1(17) DNA. The 1610 bp of HSV-1 DNA coded for a 536 amino acid (AA) region which were located between AA 254 and 790 of the DNA polymerase enzyme. Comparison of the 536 AA sequence of neuroinvasive HSV-1(17) with the homologous area of the non-neuroinvasive HSV-2(186) DNA polymerase indicated that the two polymerases differed at 56 AA positions. In addition, this area of the HSV-1(17) DNA polymerase was 5 AA acids shorter than the HSV-2(186) DNA polymerase. Specific amino acid changes that might account for the neuroinvasive phenotype of HSV-R(D1) are discussed.

Amino Acid Sequence↗

PubMed1991

Evidence endogenous interferon production contributed to the lack of ocular virulence of an HSV intertypic recombinant.

An intertypic recombinant isolated from rabbit kidney cells following co-transfection of HSV-1(17) and HSV-2(186) DNA failed to induce overt ocular pathology when inoculated onto the murine sacrificed cornea at concentrations as high as 10(7) PFU per eye. In contrast, both parents induced corneal disease at a 1000-fold lower dose. The reason(s) for the failure of the intertypic recombinant, designated RO25X, to induce corneal pathology was investigated. It was found that the recombinant was 100-fold more sensitive to the inhibitory effects of interferon (IFN) alpha/beta than the parent strains in corneal button growth studies in vitro. R025X readily grew in cultured mouse corneal fibroblasts at a low multiplicity of infection. However, the peak titer was approximately 8-fold lower than that of strain 17. Addition of rabbit anti-IFN alpha/beta to the culture medium resulted in a 4 to 5-fold increase in infectious titer compared to its growth in the absence of antiserum. Most significantly, when mice were pre-treated in vivo with anti-IFN alpha/beta 24 hours prior to virus corneal infection, 67% of the recipients developed moderate to severe stromal keratitis, whereas none of the controls developed corneal pathology. Blepharitis was also significantly increased in incidence and severity in the antiserum treated hosts. We conclude that the inability of R025X to induce ocular disease was due, at least in part, to the inhibitory effects of interferon produced in response to infection.

Animals↗

PubMed1990

Nucleotide sequences responsible for the inability of a herpes simplex virus type 2 strain to grow in human lymphocytes are identical to those responsible for its inability to grow in mouse tissues following ocular infection.

A study was undertaken to determine whether genes associated with herpes simplex virus (HSV) neuroinvasiveness in mice influence the growth of HSV in man, the virus's natural host. HSV-2(186), a nonneuroinvasive HSV strain, was found to replicate poorly (less than 3-fold) in cultures of phytohemagglutinin (PHA) stimulated human peripheral blood mononuclear cells (PBMC). In contrast, seven other HSV strains all multiplied 40- to 100-fold. The paucity of HSV-2(186) growth in PBMC was not due to a failure of this strain to grow in primary human cells because high titers (greater than 10(8) PFU/ml) were obtained following infection of human foreskin fibroblasts. The genetic basis for the deficient growth was analyzed by marker rescue experiments. Recombinant HSV-2 strains were generated in marker rescue experiments utilizing HSV-2(186) DNA and plasmids containing a cloned DNA polymerase gene isolated from a neuroinvasive HSV strain possessing the capacity to replicate in human PBMC. Progeny which rescued DNA from the cloned HSV DNA polymerase gene replicated 40- to 100-fold in PHA-stimulated PBMC. Moreover, unlike the HSV-2(186) parent, HSV-2(186) isolates possessing rescued DNA grew well in the eye, trigeminal ganglion, and brain of mice and induced fatal encephalitis. The results indicate that nucleotide sequences responsible for increasing the capacity of HSV-2(186) to grow in PBMC of man are identical to those responsible for increasing the capacity of this strain to grow in mouse tissues and to spread from the eye to the brain.

Adult↗

PubMed1990

Ocular avirulence of a herpes simplex virus type 1 strain is associated with heightened sensitivity to alpha/beta interferon.

BALB/c mice infected on the scarified cornea with herpes simplex virus type 1 strain 35 [HSV-1(35)] rarely developed ocular disease even at challenge doses as high as 10(7) PFU per eye. In contrast, HSV-1(RE) consistently induced stromal keratitis at an inoculum of 2 x 10(4) PFU. The goal of this study was to determine the reason for the difference in virulence between the two HSV strains. Both HSV-1 strains replicated to similar titers in excised corneal "buttons." However, after in vivo infection of the cornea, the growth of strain 35 was evident only during the first 24 h postinfection, whereas the replication of strain RE persisted for at least 4 days. In vitro tests revealed that HSV-1(35) was greater than 10 times more sensitive to alpha/beta interferon (IFN-alpha/beta) than HSV-1(RE). Both strains induced comparable serum levels of IFN after intraperitoneal inoculation. The kinetics of HSV-1(35) clearance from the eye was markedly altered by treatment with rabbit anti-IFN-alpha/beta. Virus titers exceeding 10(4) PFU per eye could be demonstrated 4 to 5 days postinfection in mice given a single inoculation of antiserum 1 h after infection. Furthermore, anti-IFN treatment in 3-week-old mice infected with HSV-1(35) led to the development of clinically apparent corneal disease which subsequently progressed to stromal keratitis in the majority of recipients. These results indicate that the striking difference in the capacity of HSV-1(35) and HSV-1(RE) to induce corneal disease was related to the inherently greater sensitivity of strain 35 to IFN-alpha/beta produced by the host in response to infection.

Animals↗

PubMed1990

Effective antibody therapy in herpes simplex virus ocular infection. Characterization of recipient immune response.

The immunotherapeutic potential of a monoclonal antibody specific for glycoprotein D of herpes simplex virus was evaluated in a murine ocular infection model. Passive transfer of antibody at microgram concentrations was able to promote resolution of corneal opacity and hasten healing of blepharitis. Antibody treatment did not prevent development of either a cellular or humoral antiviral immune response. In fact, kinetic studies revealed that the early delayed-type hypersensitivity response was significantly more vigorous in the treated group than in the controls. Potential explanations as to how a single microgram inoculation of antibody could exert a therapeutic effect are discussed.

Animals↗

PubMed1989

Quantitation of purified monoclonal antibody needed to prevent HSV-1 induced stromal keratitis in mice.

A purified IgG2a monoclonal antibody with a neutralizing titer of 10(4) and specificity for gD was evaluated for its therapeutic potential in a murine ocular infection model. BALB/c mice, infected on the scarified cornea with 10 times the HSV-1 strain RE concentration needed to produce severe and persistent stromal opacity, were given a single inoculation of antibody intraperitoneally 24 hours later. The animals were then followed for corneal disease development. Antibody, at concentrations as low as 10 micrograms per mouse, was strikingly effective at preventing corneal opacity. Furthermore, the corneas, once clear, remained clear whereas the controls developed +3 to +5 stromal disease which was still present 60 days post-infection. Animals that had been treated and recovered from infection were resistant to subsequent HSV-1 challenge on the opposite cornea. These results demonstrate the therapeutic potential of systemically administered microgram quantities of anti-gD antibody.

Animals↗

PubMed1988

Evidence that the gene for herpes simplex virus type 1 DNA polymerase accounts for the capacity of an intertypic recombinant to spread from eye to central nervous system.

HSV-1(17) replicates 100-fold more efficiently than HSV-2(186) within trigeminal ganglia following ocular infection. In order to identify the nucleotide sequences responsible for the differences in the capacity of the two HSV strains to grow within the peripheral nervous system, an intertypic recombinant was generated by infecting neuroblastoma cells with HSV-2(186) and a HSV strain possessing nucleotide sequences from HSV-1(17). The genome of the intertypic recombinant was composed entirely of HSV-2(186) DNA except for 2.0 kb of HSV-1(17) DNA positioned between m.u. 0.413 and 0.426. Following corneal infection of mice, the intertypic recombinant grew to higher titers in both ocular tissues and trigeminal ganglia than did the HSV-2 parent. Most significantly, the intertypic recombinant could spread into the brain from the trigeminal ganglion and kill the host whereas mice inoculated with the HSV-2(186) parent survived infection. The 2.0 kb of HSV-1(17) DNA inserted into the genome of the intertypic recombinant encodes the 5' terminus of the HSV-1 gene for DNA polymerase. Thus, the results suggest that the difference in the capacity of two HSV strains to replicate within the trigeminal ganglion of its host and to spread into the brain is determined by nucleotide sequences within the gene for DNA polymerase.

Animals↗