| 1. |
- Bourghardt Peebo, Beatrice, et al.
(författare)
-
An in Vivo Method for Visualizing Flow Dynamics of Cells within Corneal Lymphatics
- 2013
-
Ingår i: Lymphatic Research and Biology. - : Mary Ann Liebert. - 1539-6851 .- 1557-8585. ; 11:2, s. 93-100
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Monitoring the trafficking of specific cell populations within lymphatics could improve our understanding of processes such as transplant rejection and cancer metastasis. Current methods, however, lack appropriate image resolution for single-cell analysis or are incompatible with in vivo and longitudinal monitoring of lymphatics in their native state. We therefore sought to achieve high-resolution live imaging of the dynamic behavior of cells within lymph vessels in the rat cornea.Methods/Results: Inflammatory angiogenesis was induced by suture placement in corneas of Wistar rats. Pre- and up to 3 weeks post-induction, corneas were noninvasively examined by laser-scanning in vivo corneal confocal microscopy (IVCM) using only endogenous contrast. Lymph vessels and the cells harbored therein were documented by still images, real-time video, and 3D confocal stack reconstruction of live tissue. In vivo, conjunctival and corneal lymphatics were morphologically distinct, those with corneal location being one-quarter the diameter of those in the conjunctiva (p<0.001). Cells were recruited to initially empty pre-existing lymph vessels during the first day of inflammation and maintained a dense occupation of vessels for up to 7 days. A diverse population of cells (diameter range: 1.5–27.5 μm) with varying morphology was observed, and exhibited variable flow patterns and were transported singly and in clusters of at least 2–9 adherent cells.Conclusions: The in vivo microscopic technique presented enables lymph vessels and cell trafficking to be studied in high resolution in a minimally-perturbed physiologic milieu.
|
|
| 2. |
- Bourghardt Peebo, Beatrice, 1968-
(författare)
-
Angiogenesis from a new perspective
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Angiogenesis is the emergence of new blood and lymph vessels from existing ones. In the pathologic form it contributes to the onset and progression of numerous different human disorders such as cancer, inflammation, atherosclerosis and blinding eye diseases. There exist a number of models to study angiogenesis, both in vitro and in vivo, but there is no single perfect model so far. Consequently there is a need to develop new angiogenesis assays for evaluating blood and lymph vessel behaviour in different physiologic settings.The aim of this thesis was to gain insight into in vivo angiogenesis introducing a new technique in an inflammatory corneal model. The method involved in vivo examination of the cornea and subsequent comparison of in vivo findings with ex vivo immunohistochemical analysis of the same tissue samples. An existing suture model for inflammatory angiogenesis in the cornea was modified for in vivo observations with a clinically-approved corneal confocal microscope.In this thesis, corneal lymph vessels were characterized for the first time in vivo and findings from the experimental bench could be applied in a clinical setting, where presumed lymphatics were observed in a corneal transplant patient with rejection. Furthermore, the technique was extended to investigate time-lapse processes in sprouting and regressing capillaries, and led to a number of new observations. CD11b+ myeloid cells constitute the first bulk of infiltrating inflammatory cells and contribute to inflammatory sprouting and regression in numerous ways including pre-patterning of the corneal stroma and guiding of capillary sprouts. Newly formed hemangiogenic sprouts are perfused with a slow-moving fluid and have a lumen. In blood vessel regression, capillary remodeling occurred by abandonment of sprout tips in close association with macrophages and vascular loops formed by presumed intussusceptive angiogenesis. In addition, a network of pericyte- and endothelium-free basement membrane tubes was formed after desertion or degradation of vascular endothelium in former corneal capillaries.In conclusion, we introduce a new in vivo technique for investigating angiogenesis in a corneal model were in vivo findings can be interpreted with ex vivo definitions of specific cell types by immunohistochemistry. Findings from pre-clinical experiments have been possible to apply in a clinical setting when examining patients with corneal pathology.
|
|
| 3. |
- Bourghardt Peebo, Beatrice, et al.
(författare)
-
Cellular level characterization of capillary regression in inflammatory angiogenesis using an in vivo corneal model
- 2011
-
Ingår i: Angiogenesis. - : Springer Verlag (Germany). - 0969-6970 .- 1573-7209. ; 14:3, s. 393-405
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we introduce a technique for repeated, microscopic observation of single regressing capillaries in vivo in inflamed murine corneas. Natural capillary regression was initiated by removal of inflammatory stimulus during an active pro-angiogenic phase, while the additional impact of anti-angiogenic treatment with triamcinolone or bevazicumab was investigated. Capillaries regressed naturally within 1 week and treatments did not further enhance the natural regression. Morphologically, early-phase regression was characterized by significant lumen narrowing and a significant reduction in CD11b+ myeloid cell infiltration of the extracellular matrix. By 1 week, vascular remodeling occurred concomitant with CD11b+CD68+KiM2R+ mature macrophage localization on capillary walls. Empty conduits without blood flow, positive for collagen IV and devoid of vascular endothelium and pericytes, were apparent in vivo and by 3 weeks were more numerous than perfused capillaries. By 3 weeks, macrophages aggregated around remaining perfused capillaries and were observed in apposition with degrading capillary segments. Abrupt termination of capillary sprouting in our regression model further revealed vascular endothelial abandonment of sprout tips and perfused capillary loop formation within a single angiogenic sprout, possibly as an intussusceptive response to cessation of the stimulus. Finally, we observed lumen constriction and macrophage localization on capillary walls in vivo in a clinical case of corneal capillary regression that paralleled findings in our murine model.
|
|
| 4. |
- Bourghardt Peebo, Beatrice, et al.
(författare)
-
Cellular-Level Characterization of Lymph Vessels in Live, Unlabeled Corneas by In Vivo Confocal Microscopy
- 2010
-
Ingår i: Investigative Ophthalmology and Visual Science. - Rockville, MD, United States : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 51:2, s. 830-835
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE. To determine whether in vivo confocal microscopy (IVCM) of the cornea can be used for the label-free detection and monitoring of lymph vessels in live corneas.METHODS. Parallel corneal hemangiogenesis and lymphangiogenesis was induced by the placement of a single suture in one cornea of male Wistar rats. Fourteen days after suture placement and under general anesthesia, laser-scanning IVCM was performed in the vascularized region. Corneas were subsequently excised for flat-mount double immunofluorescence with a pan-endothelial marker (PECAM-1/CD31) and a lymphatic endothelial specific marker (LYVE-1). Using the suture area and prominent blood vessels as points of reference, the identical microscopic region was located in both fluorescent and archived in vivo images. Additionally, vessel diameter, lumen contrast, and cell diameter and velocity within vessels were quantified from in vivo images.RESULTS. Comparison of identical corneal regions in fluorescence and in vivo revealed prominent CD31(+)/LYVE-1(3+) lymph vessels that were visible in vivo. In vivo, corneal lymph vessels were located in the vascularized area in the same focal plane as blood vessels but had a darker lumen (P andlt; 0.001) sparsely populated by highly reflective cells with diameters similar to those of leukocytes in blood vessels (P = 0.61). Cell velocity in lymph vessels was significantly reduced compared with blood particle velocity (P andlt; 0.001). Morphologic characteristics enabled subsequent identification of corneal lymphatics in live, vascularized rat corneas before immunofluorescence labeling.CONCLUSIONS. IVCM enabled the nondestructive, label-free, in vivo detection of corneal lymphatics. IVCM provides the possibility of observing lymphatic activity in the same live corneas longitudinally and, as a clinical instrument, of monitoring corneal lymphatics in live human subjects.
|
|
| 5. |
|
|
| 6. |
- Bourghardt Peebo, Beatrice, et al.
(författare)
-
Time-Lapse In Vivo Imaging of Corneal Angiogenesis: The Role of Inflammatory Cells in Capillary Sprouting
- 2011
-
Ingår i: Investigative Ophthalmology and Visual Science. - : Research in Vision and Opthalmology. - 0146-0404 .- 1552-5783. ; 52:6, s. 3060-3068
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE. To elucidate the temporal sequence of events leading to new capillary sprouting in inflammatory corneal angiogenesis. METHODS. Angiogenesis was induced by corneal suture placement in Wistar rats. The inflamed region was examined by time-lapse in vivo confocal microscopy for up to 7 days. At 6 and 12 hours and 1, 2, 4, and 7 days, corneas were excised for flat mount immunofluorescence with primary antibodies for CD31, CD34, CD45, CD11b, CD11c, Ki-M2R, NG2, and alpha-SMA. From days 0 to 4, the in vivo extravasation and expansion characteristics of single limbal vessels were quantified. RESULTS. Starting hours after induction and peaking at day 1, CD45(+)CD11b(+) myeloid cells extravasated from limbal vessels and formed endothelium-free tunnels within the stroma en route to the inflammatory stimulus. Limbal vessel diameter tripled on days 2 to 3 as vascular buds emerged and transformed into perfused capillary sprouts less than 1 day later. A subset of spindle-shaped CD11b(+) myeloid-lineage cells, but not dendritic cells or mature macrophages, appeared to directly facilitate further capillary sprout growth. These cells incorporated into vascular endothelium near the sprout tip, co-expressing endothelial marker CD31. Sprouts had perfusion characteristics distinct from feeder vessels and many sprout tips were open-ended. CONCLUSIONS. Time-lapse in vivo corneal confocal microscopy can be used to track a temporal sequence of events in corneal angiogenesis. The technique has revealed potential roles for myeloid cells in promoting vessel sprouting in an inflammatory corneal setting.
|
|
| 7. |
- Bourghardt Peebo, Beatrice, et al.
(författare)
-
Transient Anterior Corneal Deposits in a Human Immunodeficiency Virus-Positive Patient
- 2010
-
Ingår i: CORNEA. - : Lippincott Williams and Wilkins. - 0277-3740. ; 29:11, s. 1323-1327
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To report findings of pigmented anterior corneal deposits in a human immunodeficiency virus-positive patient. Methods: Case report. A 49-year-old human immunodeficiency virus-positive patient was examined after the appearance of pigmented corneal deposits. Slit-lamp biomicroscopy, fundus photography, and laser-scanning in vivo confocal microscopy were performed to visually document the ocular condition. Results: The patient had a history of Mycobacterium avium infection and was suspected to have recovery uveitis from a cytomegalovirus infection. Small, rounded, light brown-colored deposits were distributed across the anterior cornea from limbus to limbus, bilaterally. In vivo confocal microscopy revealed the deposits to be confined to the basal epithelium and Bowman layer, whereas the posterior stroma, Descemet membrane, and the endothelium appeared normal. Systemic steroid treatment was administered, and 2 weeks later, the deposits had vanished on slit-lamp examination, whereas remnants were observed at the microscopic level. Conclusions: The deposits were unusual for their anterior corneal location and pancorneal distribution. The response to systemic steroid treatment remains unexplained and illustrates the complexity of the underlying conditions, their treatment, and the associated pathways of ocular manifestation.
|
|
| 8. |
- Frennesson, Christina, et al.
(författare)
-
Significant improvements in near vision, reading speed, central visual field and related quality of life after ranibizumab treatment of wet age-related macular degeneration
- 2010
-
Ingår i: ACTA OPHTHALMOLOGICA. - : Blackwell Publishing Ltd. - 1755-375X .- 1755-3768. ; 88:4, s. 420-425
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To investigate the effects on near visual acuity, reading speed, central visual field and related quality of life of ranibizumab treatment of wet age-related macular degeneration (AMD). Methods: The study was a prospective, non-comparative consecutive case series, followed for 3 months and investigator-driven. Thirty eyes of 30 patients with wet AMD were included, mean age 75 years (range 69-95 years). In addition to a full ophthalmological examination - including best-corrected visual acuity (BCVA; Early Treatment Diabetic Research Study chart), fundus biomicroscopy, fundus photography, fluorescein angiography, indocyanine green angiography (occult cases) and ocular coherence tomography - near visual acuity, reading speed, central visual field and quality of life for related activities were also investigated at baseline and at 3 months after ranibizumab treatment. Results: Mean BCVA increased from 62 +/- 11 to 66 +/- 14 letters at 3 months (7%; p = 0.018). Near vision improved from 9 +/- 5 to 6 +/- 3 points (33%; p = 0.0006) and reading speed increased from 59 +/- 40 to 85 +/- 50 words/min (44%; p andlt; 0.0001). The mean deviation from normal of the visual field improved from -9 +/- 7 to -6 +/- 5 dB (33%; p andlt; 0.0001). Quality of life improved for distance activities from 54 +/- 28 to 63 +/- 28 points (17%; p andlt; 0.0001) but significantly (p = 0.024) more for near activities, from 49 +/- 26 to 63 +/- 26 points (29%; p andlt; 0.0001). Reading newspaper text in the group in which the better eye was treated showed the highest increase in quality of life score of all: 116%. Conclusion: The increase in BCVA after ranibizumab treatment is well established. The present study also showed significant improvements in other important visual qualities, such as near visual acuity, reading speed, central visual field and several activities influencing quality of life. The improvement was greater for near activities than for distance activities. Therefore, the beneficial effects of ranibizumab treatment shown here are more extensive than those reported previously.
|
|
| 9. |
- Heintz, Emelie, et al.
(författare)
-
Prevalence and healthcare costs of diabetic retinopathy : a population-based register study in Sweden
- 2010
-
Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 53:10, s. 2147-2154
-
Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesisThe aim of the present study was to estimate the prevalence and healthcare costs of diabetic retinopathy (DR).MethodsThis population-based study included all residents (n = 251,386) in the catchment area of the eye clinic of Linköping University Hospital, Sweden. Among patients with diabetes (n = 12,026), those with and without DR were identified through register data from both the Care Data Warehouse in Östergötland, an administrative healthcare register, and the Swedish National Diabetes Register. Healthcare cost data were elicited by record linkage of these two registers to data for the year 2008 in the Cost Per Patient Database developed by Östergötland County Council.ResultsThe prevalence of any DR was 41.8% (95% CI 38.9–44.6) for patients with type 1 diabetes and 27.9% (27.1–28.7) for patients with type 2 diabetes. Sight-threatening DR was present in 12.1% (10.2–14.0) and 5.0% (4.6–5.4) of the type 1 and type 2 diabetes populations respectively. The annual average healthcare cost of any DR was €72 (€53–91). Stratified into background retinopathy, proliferative DR, maculopathy, and the last two conditions combined, the costs were €26 (€10–42), €257 (€155–359), €216 (€113–318) and €433 (€232–635) respectively. The annual cost for DR was €106 000 per 100,000 inhabitants.ConclusionsThis study presents new information on the prevalence and costs of DR. Approximately one-third of patients with diabetes have some form of DR. Average healthcare costs increase considerably with the severity of DR, which suggests that preventing progression of DR may lower healthcare costs.
|
|
| 10. |
- Heintz, Emelie, et al.
(författare)
-
QALY weights for diabetic retinopathy : a comparison of health state valuations with HUI-3, EQ-5D, EQ-VAS, and TTO.
- 2012
-
Ingår i: Value in Health. - : Elsevier. - 1098-3015 .- 1524-4733. ; 15:3, s. 475-484
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To estimate quality-adjusted life-year weights for patients with diabetic retinopathy by using various methods and to investigate the empirical validity of the different measures.Methods: The study population comprised 152 patients with diabetes in Östergötland County, Sweden. Participants were interviewed by telephone by using the time trade-off (TTO) method and a visual analogue scale (EQ-VAS) (direct valuations) as well as the EuroQol five-dimensional questionnaire (EQ-5D) and the health utilities index mark 3 (HUI-3) (indirect valuations). The quality-adjusted life-year weights were adjusted for potential confounders by using analysis of covariance. The empirical validity of the measures was examined by testing their ability to detect hypothetical differences between severity levels of diabetic retinopathy and by investigating the correlation between the measures and the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25).Results: All measures detected significant differences in scores between patient groups classified according to visual impairment in the better eye (analysis of covariance, P < 0.05), but only HUI-3 and EQ-VAS detected significant differences between patient groups classified according to visual impairment or pathological progression in the worse eye. HUI-3 recorded a difference of 0.43 in values between normal vision and blindness in the better eye, which was more than twice the differences captured by the other measures (0.15–0.20). In addition, HUI-3 showed the highest correlation with NEI VFQ-25 (r = 0.54; P < 0.001).Conclusions: In cost-utility analyses, the choice of quality-adjusted life-year measure may affect whether an intervention is considered cost-effective. Furthermore, if decisions are to be based on values from the general public, HUI-3 can be recommended for cost-utility analyses of interventions directed at diabetic retinopathy.
|
|
