Lentiviral-vector-mediated expression of murine IL-1 receptor antagonist or IL-10 reduces the severity of endotoxin-induced uveitis.

Uveitis is a sight threatening inflammatory disorder that remains a significant cause of visual loss. We investigated lentiviral gene delivery of interleukin 1 receptor antagonist (IL-1ra) or interleukin (IL)-10 to ameliorate murine endotoxin-induced uveitis (EIU). An human immunodeficiency virus-1-based vector containing the mIL-1ra or mIL-10 cDNA demonstrated high expression of biologically active cytokine. Following administration of Lenti.GFP into the anterior chamber, transgene expression was observed in corneal endothelial cells, trabecular meshwork and iris cells. To treat EIU, mice were injected with Lenti.IL-1ra, Lenti.IL-10 or a combination of these. EIU was induced 14 days after vector administration and mice were culled 12 h following disease induction. Lenti.IL-1ra or Lenti.IL-10-treated eyes showed significantly lower mean inflammatory cell counts in the anterior and posterior chambers compared with controls. The aqueous total protein content was also significantly lower in treated eyes, demonstrating better preservation of the blood-ocular barrier. Furthermore, the treated eyes showed less in vivo fluorescein leakage from inner retinal vessels compared with controls. The combination of both IL-1ra and IL-10 had no additive effect. Thus, lentiviral gene delivery of IL-1ra or IL-10 significantly reduces the severity of experimental uveitis, suggesting that lentiviral-mediated expression of immunomodulatory genes in the anterior chamber offers an opportunity to treat uveitis.

Assessment of ocular transduction using single-stranded and self-complementary recombinant adeno-associated virus serotype 2/8.

To date adeno-associated viral (AAV) vectors are the only gene therapy vectors that have been shown to efficiently transduce photoreceptor cells and have thus become the most commonly used vector for ocular transduction. Various AAV serotypes have been evaluated in the eye, the first of which was AAV2, which is able to transduce photoreceptors, retinal pigment epithelium (RPE) and retinal ganglion cells. AAV serotypes 1 and 4, as well as AAV2 pseudotyped with these capsids, only transduce the RPE. AAV serotype 5 and AAV2/5 transduce the photoreceptors as well as RPE, but not retinal ganglion cells. Here, we assessed the capacity of the novel serotype AAV2/8 to transduce various ocular tissues of the adult murine retina by administering AAV2/8 green fluorescent protein intravitreally, subretinally and intracamerally. We also determined the kinetics and efficiency of self-complementary AAV (scAAV) vectors of serotypes 2/2, 2/5 and 2/8 and compared them with single-stranded AAV (ssAAV). We found that ssAAV2/8 transduces photoreceptors and RPE more efficiently than ssAAV2/2 and ssAAV2/5, and that scAAV2/8 had faster onset and higher transgene expression than ssAAV2/8. This improved transduction efficiency might facilitate the development of improved gene therapy protocols for inherited retinal degenerations, particularly those caused by defects in photoreceptor-specific genes.

Risks of relapse in patients with acute anterior uveitis.

AIM: To quantify the rate of recurrence of acute anterior uveitis (AAU), and evaluate the influence of associated risk factors. METHODS: We retrospectively reviewed the case notes of 185 patients with acute anterior uveitis, from their time of presentation to August 2001. The time to the first three recurrences of AAU from the onset of the disease was recorded, as well as the site of recurrence. Information regarding risk factors (for example (HLA-B27) status, spondyloarthropathy (SpA), family history of AAU/SpA and history of non-specific joint pain) were also collected. RESULTS: Patients were followed up until their third relapse, or up to the censoring date (August 2001) if less than three relapses had occurred. The median length of follow-up was 35 months. One hundred and twenty-two patients (66%) developed at least one relapse and 67 (36%) had three or more relapses. Kaplan-Meier estimate of median interval between disease onset and the first relapse was 24 months 95% CI (16 to 34) and between the first and second relapse was 14 months 95% CI (9 to 22), and was 15 months 95% CI (10 to 25) months between the second and third relapse. Using Cox regression only the number of previous relapses was significantly associated with the risk of AAU recurrence. There was no significant association between other reported risk factors and the risk of relapse, and neither did any risk factor significantly modify the association between previous relapses and AAU recurrence (p>0.066 for all interactions). There was a borderline significant difference in survival according to the laterality pattern of recurrences (ipsilateral, alternate, or bilateral) with a slightly greater than expected number of events in those with bilateral recurrence (p = 0.048). CONCLUSION: Patients with previous relapse(s) of AAU have a greater risk of AAU recurrence compared to those at disease onset but the risk of recurrence appears not to increase in a dose-response manner with increasing number of previous relapses. Demographic and extraocular features do not appear to influence the rate, or risk of recurrence of AAU.

Diagnostic effectiveness of noncontact slitlamp examination in the identification of retinal tears.

PURPOSE: To compare the diagnostic accuracy of noncontact slitlamp examination with indirect ophthalmoscopy and scleral depression, in the identification of retinal tears. METHODS: A prospective study was performed using 17 patients who were referred with retinal tears. All were initially examined at the slitlamp with a hand-held Volk (noncontact) lens. The same observer then carried out indirect ophthalmoscopy with scleral indentation. RESULTS: In 17 eyes a total of 18 acute retinal u-tears were found. A total of 16 tears were picked up at the initial examination at the slitlamp (89%), while two were missed (11%). CONCLUSIONS: Indirect ophthalmoscopy with scleral depression is the 'gold standard' for the identification of peripheral retinal tears. This small study has shown that although the majority of these can be picked up by the use of a noncontact lens at the slitlamp, 11% were missed using this technique.