Influence of administration dose and route on the immunogenicity and protective efficacy of BBG2Na, a recombinant respiratory syncytial virus subunit vaccine candidate

The immunogenicity and protective efficacy of BBG2Na, a novel recombinant respiratory syncytial virus subunit vaccine candidate, was assessed in BALB/c mice under various conditions of dose, administration route and number of immunisations. A single intra-peritoneal (i.p.) dose of 2 microg, or two doses of 0.2 microg, were sufficient to induce elevated RSV-A serum antibodies and sterilising lung protective immunity. Serum antibody titres were significantly boosted following second immunisations, but not a third. Of three routes of immunisation, i.p. induced the highest RSV-A antibody titres, followed in efficacy by the intra-muscular (i. m.) and subcutaneous (s.c.) routes. Nonetheless, all three routes induced comparable and sterilising lung protection. In contrast, upper respiratory tract protection was observed only after i.p. vaccination, although significant viral titre reductions were evident following i.m. or s.c. immunisations. Interestingly, Pepscan analyses indicated that antibody epitope usage was highest in i.p. and lowest in i.m. immunised mice, respectively. Nonetheless, all routes resulted in antibody responses to known lung protective epitopes (protectopes). Thus, the prevention of serious lower respiratory tract disease, the principle goal of a RSV vaccine, but not URT infection, is dose dependent but unlikely to be influenced by the route of BBG2Na administration.     

Immunohistochemical localization of MYOC/TIGR protein in the trabecular tissue of normal and glaucomatous eyes

PURPOSE: To examine immunohistochemically the localization of myocilin/trabecular meshwork inducible glucocorticoid response (MYOC/TIGR) protein in the glaucomatous and normal trabecular meshworks. METHODS: Trabecular tissues were used from one eye with late-onset goniodysgenetic glaucoma, three with primary open angle glaucoma (one of which had the MYOC/TIGR gene mutation), two with exfoliation glaucoma and one without glaucoma. For light microscopic immunohistochemistry, frozen sections were stained by the avidin-biotin complex method using anti-MYOC/TIGR polyclonal antibody. For electron microscopic immunohistochemistry, the pre-embedding method using the same antibody was performed. Double immunostaining using both anti-MYOC/TIGR and anti-type VI collagen antibodies was done by the immunofluorescence method. RESULTS: With light microscopy, immunoreactivity was seen in the whole trabecular meshwork of each of the specimens. No notable differences were detected in staining among the types of glaucoma, or between the eyes with and those without the gene mutation. Under electron microscopy, immunoreaction products were observed not only in the cytoplasm of the trabecular cells but also in the extracellular matrix, where staining was associated with the long-spacing collagen, fine granular materials and possibly microfibrils. With double immunohistochemistry, MYOC/TIGR was colocalized with type VI collagen in the trabecular meshwork. CONCLUSIONS: In glaucomatous and normal trabecular meshworks, the MYOC/TIGR protein is distributed in the extracellular matrix colocalizing with type VI collagen.     

Quantification of aqueous melanin granules, intraocular pressure and glaucomatous damage in primary pigment dispersion syndrome

OBJECTIVE: Aqueous melanin granules may be accurately quantified with the laser flare-cell meter and have been demonstrated to be increased in primary pigment dispersion syndrome (PDS). It was the aim of this study to correlate intraocular pressure, glaucomatous damage of the optic nerve head, and visual field defects with the number of aqueous melanin granules in PDS. DESIGN: Cross-sectional study. PARTICIPANTS: Thirty-nine eyes of 21 patients with PDS and either ocular hypertension or pigmentary glaucoma. MAIN OUTCOME MEASURES: A 24-hour intraocular pressure (IOP) profile, automated perimetry (Octopus G1), and analysis of photostereographs and HRT (Heidelberg Retina Tomograph) images of the optic disc were performed. Aqueous melanin granules were quantified using the cell count mode of the laser flare-cell meter (KOWA FC-1000) with undilated and dilated pupils. Granule counts were correlated with maximum and mean IOP, maximum range (amplitude) of IOP, mean defect of automated perimetry (G1-program), and damage to the optic disc was measured with the HRT. RESULTS: The number of aqueous melanin granules showed a strong correlation with maximum IOP in both undilated (r = 0.72, P < 0.001) and dilated eyes (r = 0.5, P = 0.02). A marginal correlation was found with the IOP range (r = 0.43, P = 0.04) and the mean defect of automated perimetry (r = 0.41, P = 0.06) in undilated eyes. The mean IOP and HRT measurements of the optic disc (area, volume of the neuroretinal rim, third moment in contour) showed no statistically significant correlation with the number of aqueous melanin granules (r < 0.4, P > 0.2). CONCLUSIONS: A larger number of aqueous melanin granules is strongly associated with high IOP and also with visual field loss, providing additional evidence of the relation between aqueous melanin dispersion and development of pigmentary glaucoma. Quantification of aqueous melanin granules with the laser flare-cell meter might be useful for evaluation of treatment effects, including laser iridotomy, in patients with PDS.     

Peripartum colloid osmotic pressures: correlation with serum proteins

Colloid osmotic pressure is a principal regulator of capillary fluid exchange. Alterations in colloid osmotic pressure in preeclamptic patients, as well as significant peripartum changes in colloid osmotic pressure in normotensive patients, are reported. In a study of 72 normotensive and preeclamptic patients, peripartum colloid osmotic pressure, serum albumin, and total serum protein were compared. Both groups exhibited significantly lower colloid osmotic pressure in the postpartum period than that measured antepartum. The mean antepartum colloid osmotic pressure in preeclamptic patients was significantly lower than in normotensive subjects. Regression equations were calculated [colloid osmotic pressure = 5.21 (total serum protein) -11.4 (r2 = 0.851)] and [colloid osmotic pressure = 8.1 (serum albumin) -8.2 (r2 = 0.891)]. Within the physiologic ranges most commonly reported for normotensive and preeclamptic patients, the use of these equations allowed calculation of colloid osmotic pressure to within 10% of measured values in 75 and 80% of the cases, respectively. Where direct measurement of colloid osmotic pressure is not readily available, calculated values may be helpful in patient management.     

Blood-aqueous barrier after phacoemulsification with posterior chamber lens implantation; foldable acrylate lens vs PMMA lens-- a clinical study on 46 eyes

BACKGROUND: Cataract surgery leads to a more or less pronounced postoperative inflammation due to breakdown of the blood-aqueous barrier. This alteration of the blood-aqueous barrier can be reduced by minimally invasive surgery. The purpose of this study was to quantify the early course of the postoperative alteration of the blood-aqueous barrier following phacoemulsification with implantation of conventional PMMA posterior chamber lens (IOL) in comparison with foldable acrylic lens implantation. PATIENTS AND METHODS: Forty-six eyes of 46 patients (age 63 +/- 8.8 years) without preexisting deficiences of the blood-aqueous-barrier or previous intraocular surgeries were divided into two groups: group 1 (24 patients): phacoemulsification with one-piece-PMMA-IOL implantation (6.5 mm corneoscleral tunnel incision); group 2 (22 patients): phacoemulsification with foldable acrylic-IOL implantation (3.5 mm incision, 15 patients with corneoscleral tunnel and 7 patients with clear cornea incision). All surgical procedures were performed by one surgeon. The postoperative treatment was standardized. Alteration of the blood-aqueous barrier was quantified by the laser flare-cell meter (Kowa, FC-1000) preoperatively and on the first and the second day after surgery. RESULTS: Preoperative aqueous flare values (photon counts/ms) were comparable in both groups (6.7 +/- 2.7 versus 5.6 +/- 2.7 respectively, p = 0.1). On day 1, aqueous flare in group 1 (9.7 +/- 2.9) was not statistically significantly higher than in group 2 (9.2 +/- 2.2, p = 0.2) and remained relatively constant on day 2 after surgery (9.3 +/- 3.3), whereas the aqueous flare values in group 2 decreased statistically significant (6.7 +/- 2.3, p = 0.01). Postoperatively, there was no statistically significant difference of aqueous flare values between eyes with corneoscleral tunnel incision and eyes with clear corneal incision (p = 0.7) in group 2. CONCLUSIONS: Our study shows that phacoemulsification with foldable IOL implantation leads to a mild and short-lasting alteration of the blood-aqueous barrier. Thus, implantation of foldable IOL may be useful in eyes especially with preexisting alteration of the blood-aqueous-barrier.     

Detecting disorder in spatial vision

In normal foveal vision, visual space is accurately mapped from retina to cortex. However, the normal periphery, and the central field of strabismic amblyopes have elevated position discrimination thresholds, which have often been ascribed to increased 'intrinsic' spatial disorder. In the present study we evaluated the sensitivity of the human visual system (both normal and amblyopic) to spatial disorder, and asked whether there is increased 'intrinsic' topographical disorder in the amblyopic visual system. Specifically, we measured thresholds for detecting disorder (two-dimensional Gaussian position perturbations) either in a horizontal string of N equally spaced samples (Gabor patches), or in a ring of equally spaced samples over a wide range of feature separations. We also estimated both the 'equivalent intrinsic spatial disorder' and sampling efficiency using an equivalent noise approach. Our results suggest that both thresholds for detecting disorder, and equivalent intrinsic disorder depend strongly on separation, and are modestly increased in strabismic amblyopes. Strabismic amblyopes also show markedly reduced sampling efficiency. However, neither amblyopic nor peripheral vision performs like ideal or human observers with added separation-independent positional noise. Rather, the strong separation dependence suggests that the 'equivalent intrinsic disorder' may not reflect topographic disorder at all, but rather may reflect an abnormality in the amblyopes' Weber relationship.     

Dorzolamide and corneal recovery from edema in patients with glaucoma or ocular hypertension

PURPOSE: To investigate whether dorzolamide alters corneal hydration control in patients with glaucoma or ocular hypertension. METHODS: Pachymetry, tonometry, and endothelial cell density were measured by a masked observer in 19 subjects with bilateral glaucoma or ocular hypertension. They were treated with 2% dorzolamide in one eye, and with saline in the other, before wearing contact lenses under patched eyes. Corneal thickness, measured each 30 minutes up to 4.5 hours after contact lens removal, enabled estimation of percentage recovery per hour and time for 95% of corneal thickness recovery for both eyes. Seven patients repeated this test after 1 year of dorzolamide use, and their results were compared with those of the preceding year. RESULTS: After induction of hypoxic corneal edema, there was no significant difference between paired corneas in swelling levels (60.0+/-11.8 and 59.8+/-12.9 microm) (P = .94), time to 95% recovery (440.6+/-255.8 and 445.4+/-186.7 minutes) (P = .93), and percentage recovery per hour (38.1%+/-10.9% and 36.1%+/-9.6%) (P = .40). Subjects followed up after 1 year of dorzolamide use did not differ significantly in values of endothelial cell density, percentage recovery per hour, or time to 95% recovery from those obtained a year before. One subject developed persistent corneal edema after his stress test in the eye treated with dorzolamide. CONCLUSION: There is no significant difference in the recovery from induced corneal edema after either a short-term or 1-year use of dorzolamide in patients with glaucoma or ocular hypertension with a normal corneal endothelium. One patient had persistent corneal edema after the stress test was performed on the dorzolamide-treated eye.     

Genetic screening in a large family with juvenile onset primary open angle glaucoma

AIMS: A number of genetic loci have been implicated in the pathogenesis of primary open angle glaucoma (POAG). The aim of this study was to identify the genetic cause of POAG in a large Scottish family and, if possible, offer genetic screening and advice to family members. METHODS: Family members were examined to determine their disease status. Base excision sequence scanning was carried out in order to test for the presence of a POAG causing mutation at known genetic loci. Direct DNA sequencing was performed in order to determine the mutation sequence. RESULTS: All family members of known affected disease status and two family members of unknown disease status were found to have a mutation in the TIGR gene. The mutation resulted in the substitution of a glycine residue with an arginine residue at codon 252 (Gly252Arg). No other sequence variations were present in any members of the family. CONCLUSION: The Gly252Arg mutation in the TIGR gene results in the development of POAG in this family. It was possible to identify younger, currently unaffected, members of the family who carry the mutation and who are therefore at a very high risk of developing POAG themselves. This is the first demonstration that Gly252Arg can be a disease causing mutation rather than a benign polymorphism. The possible pathogenic mechanisms and wider implications of the mutation are considered.