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A B Nesburn

Publications and source records attributed to A B Nesburn.

At least 19 recordsLinked to original sources
PubMed1995

Local expression of tumor necrosis factor alpha and interleukin-2 correlates with protection against corneal scarring after ocular challenge of vaccinated mice with herpes simplex virus type 1.

To correlate specific local immune responses with protection from corneal scarring, we examined immune cell infiltrates in the cornea after ocular challenge of vaccinated mice with herpes simplex virus type 1 (HSV-1). This is the first report to examine corneal infiltrates following ocular challenge of a vaccinated mouse rather than following infection of a naive mouse. Mice were vaccinated systemically with vaccines that following ocular challenge with HSV-1 resulted in (i) complete protection against corneal disease (KOS, an avirulent strain of HSV-1); (ii) partial protection, resulting in moderate corneal disease (baculovirus-expressed HSV-1 glycoprotein E [gE]); and (iii) no protection, resulting in severe corneal disease (mock vaccine). Infiltration into the cornea of CD4+ T cells, CD8+ T cells, macrophages, and cells containing various lymphokines was monitored on days 0, 1, 3, 7, and 10 postchallenge by immunocytochemistry of corneal sections. Prior to ocular challenge, no eye disease or corneal infiltrates were detected in any mice. KOS-vaccinated mice developed high HSV-1 neutralizing antibody titers (> 1:640) in serum. After ocular challenge, they were completely protected against death, developed no corneal disease, and had no detectable virus in their tear films at any time examined. In response to the ocular challenge, these mice developed high local levels of infiltrating CD4+ T cells and cells containing interleukin-2 (IL-2), IL-4, IL-6, or tumor necrosis factor alpha (TNF-alpha). In contrast, only low levels of infiltrating CD8+ T cells were found, and gamma interferon (IFN-gamma)-containing cells were not present until day 10. gE-vaccinated mice developed neutralizing antibody titers in serum almost as high as those of the KOS-vaccinated mice (> 1:320). After ocular challenge, they were also completely protected against death. However, the gE-vaccinated mice developed low levels of corneal disease and virus was detected in one-third of their eyes. Compared with KOS-vaccinated mice, the gE-vaccinated mice had a similar pattern of IFN-gamma, but a delay in the appearance of CD4+ T cells, CD8+ T cells, and IL-4-, IL-6-, and TNF-alpha-containing cells. In sharp contrast to those of the KOS-vaccinated mice, no cells containing IL-2 were detected in the eyes of gE-vaccinated mice at any time. Mock-vaccinated mice developed no detectable neutralizing antibody titer and were not protected from lethal HSV-1 challenge.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

An avirulent ICP34.5 deletion mutant of herpes simplex virus type 1 is capable of in vivo spontaneous reactivation.

The herpes simplex virus type 1 (HSV-1) ICP34.5 gene is a neurovirulence gene in mice. In addition, some ICP34.5 mutants have been reported to have a reduced efficiency of induced reactivation as measured by in vitro explantation of latently infected mouse ganglia. However, since spontaneous reactivation is almost nonexistent in mice, nothing has been reported on the effect of ICP34.5 mutants on spontaneous reactivation in vivo. To examine this, we have deleted both copies of the ICP34.5 neurovirulence gene from a strain of HSV-1 (McKrae) that has a high spontaneous reactivation rate in rabbits and used this mutant to infect rabbit eyes. All rabbits infected with the ICP34.5 mutant virus (d34.5) survived, even at challenge doses greater than 4 x 10(7) PFU per eye. In contrast, a 200-fold-lower challenge dose of 2 x 10(5) PFU per eye was lethal for approximately 50% of rabbits infected with either the wild-type McKrae parental virus or a rescued ICP34.5 mutant in which both copies of the ICP34.5 gene were restored. In mice, the 50% lethal dose of the ICP34.5 mutant was over 10(6) PFU, compared with a value of less than 10 PFU for the rescued virus. The ICP34.5 mutant was restricted for replication in rabbit and mouse eyes and mouse trigeminal ganglia in vivo. The spontaneous reactivation rate in rabbits for the mutant was 1.4% as determined by culturing tear films for the presence of reactivated virus. This was more than 10-fold lower than the spontaneous reactivation rate determined for the rescued virus (19.6%) and was highly significant (P < 0.0001, Fisher exact test). Southern analysis confirmed that the reactivated virus retained both copies of the ICP34.5 deletion. Thus, this report demonstrates that (i) the ICP34.5 gene, known to be a neurovirulence gene in mice, is also important for virulence in rabbits and (ii) in vivo spontaneous reactivation of HSV-1 in the rabbit ocular model, although reduced, can occur in the absence of the ICP34.5 gene.

Animals↗
PubMed1995

Protection against herpes simplex virus-induced eye disease after vaccination with seven individually expressed herpes simplex virus 1 glycoproteins.

PURPOSE: To compare the efficacy of each of seven expressed herpes simplex virus 1 (HSV-1) glycoproteins as vaccines to protect against ocular disease after primary ocular HSV-1 infection. METHODS: Mice were vaccinated three times with equal amounts of each of seven individually expressed HSV-1 glycoproteins (gB, gC, gD, gE, gG, gH, and gI) and then ocularly challenged with McKrae, a corneal disease-producing strain of HSV-1. Viral clearance from the eye, blepharitis, keratitis, and neovascularization were determined at various times after infection. RESULTS: Mice vaccinated with gD or gB had the best protection against eye disease. Vaccination with gI, gC, or gE produced moderate protection against eye disease. Vaccination with gG produced less protection, and vaccination with gH produced no apparent protection against eye disease. CONCLUSIONS: These results suggest that when used as vaccines, different HSV-1 glycoproteins provide different levels of protection against HSV-1-induced eye disease. Based on comparison with the authors' previously published results, the ability of each glycoprotein to protect against eye disease correlated with the ability of the glycoprotein to induce high serum neutralizing antibody titers and killer cell activity. Results suggest that the effectiveness of these seven glycoproteins in protecting against eye disease can be ranked as follows: gD > gB > gI > (gC = gE) > gG > gH.

Animals↗
PubMed1994

Expression and characterization of baculovirus expressed herpes simplex virus type 1 glycoprotein L.

We have constructed a recombinant baculovirus expressing high levels of the herpes simplex virus type 1 (HSV-1) glycoprotein L (gL) in Sf9 cells. Sf9 cells infected with this recombinant virus synthesized three polypeptides of 26-27 kDa 28 kDa, and 31 kDa. The 28 and 31 kDa species were sensitive to tunicamycin and N-glycosidase F (PNGase F) treatment, suggesting that they were glycosylated. As shown by both indirect immunofluorescence and Western blot analysis, using polyclonal antibodies to synthetic gL peptides indicated that the baculovirus expressed gL was abundant on the surface of baculovirus gL infected Sf9 cells. A small fraction of the 31 kDa polypeptide was secreted into the extracellular medium as judged by Western blot analysis. The secreted form of gL was completely resistant to Endoglycosidase H (Endo-H), while the membrane associated form of gL was only partially resistant to Endo-H treatment, suggesting that the secreted gL represented a subpopulation of the membrane bound gL. Mice vaccinated with baculovirus expressed gL produced serum antibodies that reacted with authentic HSV-1 gL. However, these mice produced no HSV-1 neutralizing antibody (titer < 1:10) and they were not protected from lethal intraperitoneal or lethal ocular challenge with HSV-1. Thus, when used as a vaccine in the mouse model, gL, similar to our findings with HSV-1 gH, but unlike our results with the other 6 HSV-1 glycoproteins that we have expressed in this baculovirus system, did not provide any protection against HSV-1 challenge.

Animals↗
PubMed1994

Results of excimer laser photorefractive keratectomy for the correction of myopia.

PURPOSE: This report summarizes the authors' 3-year experience with excimer laser photorefractive keratectomy on 240 eyes of 161 patients. METHODS: With constant laser emission parameters, nitrogen flow across the cornea was used on 79 eyes, whereas 161 eyes had no nitrogen flow. Of the 240 eyes, 74 were operated on without suction ring fixation. Postoperative pain management included patching and oral analgesics in 77 eyes and the use of topical diclofenac or ketorolac and a therapeutic soft contact lens in 163 eyes. Follow-up ranged from 1 month (206 eyes) to 36 months (10 eyes). RESULTS: At 3 months, 88% (144 eyes) had uncorrected visual acuity of 20/40 or better; 86% (151 eyes) had corrected visual acuity to within +/- 1 diopter of intended correction, and 10% (17 eyes) lost two or more lines of best-corrected visual acuity. At 12 months, 89% (122 eyes) achieved uncorrected visual acuity of 20/40 or better, 79% (115 eyes) had corrected visual acuity to within +/- 1 diopter of intended correction, and 4% (6 eyes) lost two or more lines of best-corrected visual acuity. At 24 months, 92% (44 of 48 eyes) had uncorrected visual acuity of 20/40 or better, 86% (44 of 51 eyes) had corrected visual acuity to within +/- 1 diopter of intended correction, and 5% (2 eyes) lost two or more lines of best-corrected visual acuity. At 36 months, 90% (9 eyes) achieved an uncorrected visual acuity of 20/40 or better, 90% (9 eyes) had corrected visual acuity to within +/- 1 diopter of intended correction, and no eyes lost two or more lines of best-corrected visual acuity. CONCLUSIONS: The results obtained with one procedure are within accepted standards of accuracy for refractive surgery, and there is the potential for refinement of the final optical correction. Complication rates are low and are not vision threatening. They included increased intraocular pressure, epithelial "map dot" changes, and recurrent corneal erosion syndrome, "central islands," and others. Photorefractive keratectomy appears to be a safe procedure over the short and medium term.

Adult↗
PubMed1994

A retrospective study of disposable extended wear lenses in 100 patients: year 3.

We present the results of the third year of follow-up of a group of 100 patients wearing disposable contact lenses on an extended wear basis. Thirty-seven males and 63 females participated in the study. The mean patient age was 41.76 years (SD: 14.5), and the mean patient follow-up time was 37.73 months (SD: 5.25). Twenty-three patients were lost to follow-up. Most of those lost to follow-up decided to purchase their lenses at discount outlets. A case of recurrent corneal ulcers in a patient wearing lenses obtained from a discount outlet is described. A significant decrease in events defined as complications (14 events) was noted as compared with the second year (32 events) of the study. One corneal infiltrate and one corneal ulcer were noted. Disposable extended wear lenses may be a reasonable means of vision correction in the properly selected patient with appropriate follow-up provided by a well-trained eye care practitioner.

Adolescent↗
PubMed1994

The latency-associated transcript gene of herpes simplex virus type 1 (HSV-1) is required for efficient in vivo spontaneous reactivation of HSV-1 from latency.

During herpes simplex virus type 1 (HSV-1) neuronal latency, the only viral RNA detected is from the latency-associated transcript (LAT) gene. We have made a LAT deletion mutant of McKrae, an HSV-1 strain with a very high in vivo spontaneous reactivation rate. This mutant (dLAT2903) lacks the LAT promoter and the first 1.6 kb of the 5' end of LAT. dLAT2903 was compared with its parental virus and with a rescued virus containing a restored LAT gene (dLAT2903R). Replication of the LAT mutant in tissue culture, rabbit eyes, and rabbit trigeminal ganglia was similar to that of the rescued and parental viruses. On the basis of semiquantitative PCR analysis of the amount of HSV-1 DNA in trigeminal ganglia, the LAT mutant was unimpaired in its ability to establish latency. In contrast, spontaneous reactivation of dLAT2903 in the rabbit ocular model of HSV-1 latency and reactivation was decreased to approximately 33% of normal. This decrease was highly significant (P < 0.0001) and demonstrates that in an HSV-1 strain with a high spontaneous reactivation rate, deletion of LAT can dramatically decrease in vivo spontaneous reactivation. We also report here that deletion of LAT appeared to eliminate rather than just reduce in vivo induced reactivation.

Animals↗
PubMed1994

Expression of seven herpes simplex virus type 1 glycoproteins (gB, gC, gD, gE, gG, gH, and gI): comparative protection against lethal challenge in mice.

We have constructed recombinant baculoviruses individually expressing seven of the herpes simplex virus type 1 (HSV-1) glycoproteins (gB, gC, gD, gE, gG, gH, and gI). Vaccination of mice with gB, gC, gD, gE, or gI resulted in production of high neutralizing antibody titers to HSV-1 and protection against intraperitoneal and ocular challenge with lethal doses of HSV-1. This protection was statistically significant and similar to the protection provided by vaccination with live nonvirulent HSV-1 (90 to 100% survival). In contrast, vaccination with gH produced low neutralizing antibody titers and no protection against lethal HSV-1 challenge. Vaccination with gG produced no significant neutralizing antibody titer and no protection against ocular challenge. However, gG did provide modest, but statistically significant, protection against lethal intraperitoneal challenge (75% protection). Compared with the other glycoproteins, gG and gH were also inefficient in preventing the establishment of latency. Delayed-type hypersensitivity responses to HSV-1 at day 3 were highest in gG-, gH-, and gE-vaccinated mice, while on day 6 mice vaccinated with gC, gE, and gI had the highest delayed-type hypersensitivity responses. All seven glycoproteins produced lymphocyte proliferation responses, with the highest response being seen with gG. The same five glycoproteins (gB, gC, gD, gE, and gI) that induced the highest neutralization titers and protection against lethal challenge also induced some killer cell activity. The results reported here therefore suggest that in the mouse protection against lethal HSV-1 challenge and the establishment of latency correlate best with high preexisting neutralizing antibody titers, although there may also be a correlation with killer cell activity.

Animals↗
PubMed1994

Characterization of baculovirus-expressed herpes simplex virus type 1 glycoprotein K.

The DNA region encoding the complete herpes simplex virus type 1 (HSV-1) glycoprotein K (gK) was inserted into a baculovirus transfer vector, and recombinant viruses expressing gK were isolated. Four gK-related recombinant baculovirus-expressed peptides of 29, 35, 38, and 40 kDa were detected with polyclonal antibody to gK. The 35-, 38-, and 40-kDa species were susceptible to tunicamycin treatment, suggesting that they were glycosylated. The 38- and 40-kDa species corresponded to partially glycosylated precursor gK (pgK) and mature gK, respectively. The 29-kDa peptide probably represented a cleaved, unglycosylated peptide. The 35-kDa peptide probably represented a cleaved, glycosylated peptide that may be a precursor to pgK. Indirect immunofluorescence with polyclonal antibody to gK peptides indicated that the recombinant baculovirus-expressed gK was abundant on the surface of the insect cells in which it was expressed. Mice vaccinated with the baculovirus-expressed gK produced very low levels (< 1:10) of HSV-1 neutralizing antibody. Nonetheless, these mice were partially protected from lethal challenge with HSV-1 (75% survival). This protection was significant (P = 0.02). Despite some protection against death, gK-vaccinated mice showed no protection against the establishment of latency. Surprisingly, gK-vaccinated mice that were challenged ocularly with a stromal disease-producing strain of HSV-1 had significantly higher levels of ocular disease (herpes stromal keratitis) than did mock-vaccinated mice. In summary, this is the first report to show that vaccination with HSV-1 gK can provide protection against lethal HSV-1 challenge and that vaccination with an HSV-1 glycoprotein can significantly increase the severity of HSV-1-induced ocular disease.

Animals↗
PubMed1994

Vaccine therapy for ocular herpes simplex virus (HSV) infection: periocular vaccination reduces spontaneous ocular HSV type 1 shedding in latently infected rabbits.

Periocular vaccination of rabbits with preexisting herpes simplex virus type 1 (HSV-1) latent infection with recombinant HSV-2 glycoproteins B and D (gB2 and gD2) plus adjuvant significantly reduced ocular viral shedding. Rabbits were infected in both eyes with HSV-1 strain McKrae. Following HSV-1 infection and the establishment of latency (28 days postinfection), rabbits were given a periocular subconjunctival vaccination three times at 3-week intervals. Beginning 3 weeks after the final vaccination, tear films were collected daily and cultured to detect the presence of HSV-1 and determine the spontaneous HSV-1 ocular shedding rates. Periocular vaccination increased the mean HSV-1 serum neutralizing antibody titer to fivefold above that seen in mock-vaccinated latently infected rabbits. gB enzyme-linked immunosorbent assay (ELISA) antibody titers were increased approximately 8-fold, and gD ELISA antibody titers were increased 60-fold. These increases were all statistically significant (P < 0.0001). In two independent experiments, vaccination reduced the spontaneous shedding rate by approximately 2.5-fold (P < 0.0004). In addition, the percentage of eyes that never shed virus during the 6 week postvaccination test period increased threefold (20% in controls versus 60% in vaccinated animals; P < 0.007). These results show that spontaneous ocular shedding of HSV-1 in latently infected rabbits can be significantly reduced by local periocular vaccination. This is the first report in any animal model of a successful therapeutic vaccine against recurrent HSV-1 ocular shedding. These results support the concept that development of a therapeutic vaccine for ocular HSV-1 recurrence in humans is possible.

Animals↗
PubMed1992

Baculovirus-expressed glycoprotein E (gE) of herpes simplex virus type-1 (HSV-1) protects mice against lethal intraperitoneal and lethal ocular HSV-1 challenge.

We have constructed a recombinant baculovirus expressing high levels of the herpes simplex virus type 1 (HSV-1) glycoprotein E (gE) in Sf9 cells. The expressed gE migrated on gels as a double band with apparent molecular weights of 68 and 70 kDa. The recombinant gE was glycosylated based on its susceptibility to tunicamycin treatment and was transported to the membrane of Sf9 cells based on indirect immunofluorescence. Mice vaccinated with gE developed high serum titers of HSV-1-neutralizing antibodies based on plaque reduction assays. gE vaccination also induced a strong delayed type hypersensitivity (DTH) response to HSV-1. In addition, mice vaccinated with the recombinant gE were protected from both intraperitoneal and ocular lethal HSV-1 challenge. To our knowledge, this is the first report in which vaccination with gE was shown to induce high neutralizing antibody titers, a DTH response, or protection against lethal HSV-1 challenge.

Animals↗
PubMed1992

Baculovirus-expressed glycoprotein G of herpes simplex virus type 1 partially protects vaccinated mice against lethal HSV-1 challenge.

The DNA sequence encoding the complete HSV-1 glycoprotein G (gG) was inserted into a baculovirus transfer vector and recombinant viruses expressing gG were isolated. Three gG-related recombinant baculovirus expressed peptides of 37, 42, and 44 kDa were detected by Western blotting using monoclonal antibody to gG. The 42- and 44-kDa species were susceptible to tunicamycin, Endoglycosidase H (Endo-H), and N-glycosidase F (PNGase F) treatments, suggesting that they were glycosylated. Although only very low levels (approximately 1:10) of HSV-1-neutralizing antibody were produced in mice vaccinated with the baculovirus gG, these mice were partially protected from lethal challenge with HSV-1 (75-78% survival) and this level of protection was highly significant (P = 0.002). This is the first report to show that vaccination with HSV-1 gG can provide mice with any level of protection against lethal HSV-1 challenge.

Animals↗
PubMed1992

Baculovirus expressed herpes simplex virus type 1 glycoprotein C protects mice from lethal HSV-1 infection.

A recombinant baculovirus (vAc-gC1) was constructed that expresses the glycoprotein C (gC) gene of herpes simplex virus type 1 (HSV-1). When Sf9 cells were infected with this recombinant, a protein that was smaller in size than authentic HSV-1 gC was detected by Western blotting using anti-gC polyclonal antibody. The recombinant gC was susceptible to tunicamycin, partially resistant to Endo-H, and was found on the membrane of Sf9 cells. Antibodies raised in mice to recombinant gC reacted with gC from HSV-1 infected cells and neutralized the infectivity of HSV-1 in vitro. Immunized mice were protected from lethal challenge with HSV-1.

Animals↗
PubMed1992

Expression of herpes simplex virus type 1 glycoprotein B in insect cells. Initial analysis of its biochemical and immunological properties.

A recombinant baculovirus (vAc-gB1) was constructed which expresses the glycoprotein B (gB) gene of herpes simplex virus type 1 (HSV-1). When Sf9 cells were infected with these recombinant viruses, a protein that was close in size to authentic HSV-1 gB was detected by gB polyclonal antibody. The recombinant gB was found on the membrane of Sf9 cells and was susceptible to tunicamycin, glycosidase F (PNGase F) and partially susceptible to Endo-H. Antibodies raised in mice to this recombinant recognized viral gB and neutralized the infectivity of HSV-1 in vitro. Mice inoculated with the recombinant gB were protected from lethal challenge with HSV-1.

Animals↗
PubMed1992

Baculovirus-expressed glycoprotein H of herpes simplex virus type 1 (HSV-1) induces neutralizing antibody and delayed type hypersensitivity responses, but does not protect immunized mice against lethal HSV-1 challenge.

We have shown previously that herpes simplex virus type 1 (HSV-1) glycoprotein H (gH) expressed by a baculovirus recombinant is transported to the cell surface in the absence of other HSV-1 gene products, and that the expressed gH has an apparent Mr similar to that of authentic HSV-1 gH. We report here that antibodies raised in mice to this baculovirus-expressed gH neutralize the infectivity of HSV-1 in vitro; this neutralizing activity was not complement-dependent. Mice vaccinated with gH also developed delayed type hypersensitivity (DTH) to HSV-1. This is the first report of expressed HSV-1 gH inducing neutralizing antibody or DTH responses in vaccinated animals. In contrast to the gH expressed in mammalian systems, the ability of this baculovirus-expressed gH to induce a neutralizing antibody response may be due to the inability of the mammalian expression system to transport gH to the cell surface. Despite inducing anti-HSV-1 neutralizing antibody and DTH responses, vaccination of mice with gH did not protect the mice against lethal intraperitoneal challenge with HSV-1.

Antibody Formation↗
PubMed1992

Expression of herpes simplex virus type 1 glycoprotein I in baculovirus: preliminary biochemical characterization and protection studies.

We have constructed a recombinant baculovirus expressing the herpes simplex virus type 1 (HSV-1) glycoprotein I (gI). Sf9 cells infected with this recombinant virus synthesized gI-related polypeptides with apparent molecular sizes of 52 and 56 kDa. The recombinant gI appeared to be glycosylated, since it was susceptible to both tunicamycin and endoglycosidase H, and the expressed gI was transported to the surface of infected cells as judged by indirect immunofluorescence. Antibodies to the recombinant gI raised in mice neutralized HSV-1 infectivity. Finally, we show here for the first time that vaccination with gI can protect mice against HSV-1 challenge.

Animals↗
PubMed1992

A retrospective study of disposable extended wear lenses in 100 patients: year 2.

We present the results of the second year of follow-up of 100 patients wearing disposable contact lenses on an extended wear basis. Thirty-seven males and 63 females participated in the study (mean age: 41.1 years +/- 13.88 (mean +/- 1 standard deviation); and the mean patient follow-up time was 26 months +/- 4.9). A total of 13 patients were lost to follow-up. Seventeen patients discontinued extended wear yet continued to wear soft lenses on a daily wear basis--the reasons for this finding are discussed. A significant decrease in the number of events defined as complications (32 events) was noted when compared to the first year of follow-up (136 events). Seven corneal infiltrates occurred during the second year, compared to 6 such events during the first year of the study. Additional complications included: giant papillary conjunctivitis (6 cases), corneal staining (5 cases), and corneal abrasions (4 cases). Disposable extended wear soft contact lenses offer a reasonable means of vision correction in the properly selected patient. At the same time, caution should be exercised in the fitting and wear of these lenses.

Adolescent↗