Adjustable suture strabismus surgery in infants and children: a 19-year experience.

PURPOSE: To evaluate the success rate of adjustable suture techniques in horizontal eye muscle surgery in children ≤15 years of age over a 19-year period by a single surgeon. METHODS: The medical records of all consecutive patients in this age group who underwent horizontal eye muscle surgery from 1989 through 2012 were reviewed retrospectively. Patients were divided into two groups: those in whom a nonadjustable suture technique was used and those in whom adjustable sutures were used. The following data were collected: type of strabismus, preoperative measurements, postoperative results, and reoperation rates. RESULTS: A total of 116 cases in the nonadjustable group and 521 cases in the adjustable group were included. In the adjustable group, adjustment was performed in 63% of the cases, because of either an under- (41%) or overcorrection (22%). The adjustment procedure was performed under topical proparacaine in 15% of cases and under intravenous propofol in 85%. For the adjustable group, 3-5 minutes more per muscle intraoperatively and 15-20 minutes for adjustment were required. No complications were encountered during the adjustment procedures. Early success rate, defined as alignment within 8Δ of straight at 3 to 6 months' postoperative follow-up, was significantly greater in the adjustable group than in the nonadjustable group (77.7% vs 64.6% [P ≤ 0.03]). Of the adjustable patients, 15% required reoperation compared with 21% of the nonadjustable patients. CONCLUSIONS: Use of adjustable sutures in horizontal eye muscle surgery in children ≤15 years of age provided an improved success rate and fewer reoperations compared with nonadjustable sutures.

Chemokine receptors CCR6 and CXCR3 are necessary for CD4(+) T cell mediated ocular surface disease in experimental dry eye disease.

CD4(+) T cells are essential to pathogenesis of ocular surface disease in dry eye. Two subtypes of CD4(+) T cells, Th1 and Th17 cells, function concurrently in dry eye to mediate disease. This occurs in spite of the cross-regulation of IFN-γ and IL-17A, the prototypical cytokines Th1 and Th17 cells, respectively. Essential to an effective immune response are chemokines that direct and summon lymphocytes to specific tissues. T cell trafficking has been extensively studied in other models, but this is the first study to examine the role of chemokine receptors in ocular immune responses. Here, we demonstrate that the chemokine receptors, CCR6 and CXCR3, which are expressed on Th17 and Th1 cells, respectively, are required for the pathogenesis of dry eye disease, as CCR6KO and CXCR3KO mice do not develop disease under desiccating stress. CD4(+) T cells from CCR6KO and CXCR3KO mice exposed to desiccating stress (DS) do not migrate to the ocular surface, but remain in the superficial cervical lymph nodes. In agreement with this, CD4(+) T cells from CCR6 and CXCR3 deficient donors exposed to DS, when adoptively transferred to T cell deficient recipients manifest minimal signs of dry eye disease, including significantly less T cell infiltration, goblet cell loss, and expression of inflammatory cytokine and matrix metalloproteinase expression compared to wild-type donors. These findings highlight the important interaction of chemokine receptors on T cells and chemokine ligand expression on epithelial cells of the cornea and conjunctiva in dry eye pathogenesis and reveal potential new therapeutic targets for dry eye disease.

Dendritic cell-derived thrombospondin-1 is critical for the generation of the ocular surface Th17 response to desiccating stress.

TSP-1 is a physiologic activator of TGF-ß, a critical induction factor for Th17-mediated immunity. The purpose of this study was to investigate the role of TSP-1 in the induction of the Th17 ocular surface response to DS. TSP-1KO and WT mice were subjected to DS5 and DS10), and parameters of ocular surface disease, including corneal barrier function, conjunctival CD4(+) T cell infiltration, and GC density, were evaluated. TSP-1KO mice subjected to DS had less corneal barrier disruption, reduced loss of PAS+ GC, and decreased CD4(+) T cell infiltration in the conjunctiva. In contrast to WT, TSP-1KO mice failed to up-regulate MMP-3 and MMP-9 mRNA transcripts in the cornea and IL-17A mRNA transcripts in the conjunctiva. RAG-1KO recipients of adoptively transferred CD4(+) T cells isolated from TSP-1KO mice subjected to DS5 showed milder dry-eye phenotype and less conjunctival inflammation than recipients of CD4(+) T cells from DS5 WT control. Reconstitution of TSP-1KO mice with WT DCs prior to DS reversed the resistance of the TSP-1KO to DS-induced immunopathology. In conclusion, DC-derived TSP-1 is critical for generating the Th17 ocular surface response to DS.

Deletion of interferon-γ delays onset and severity of dacryoadenitis in CD25KO mice.

INTRODUCTION: To investigate the role of interferon-gamma (IFN-γ) in the onset and severity of dacryoadenitis in the CD25 knockout (KO) mouse model of Sjögren Syndrome. METHODS: CD25/IFN-γ double KO (γDKO) mice were created by crossbreeding CD25KO and IFN-γKO mice. Mice were used at 8, 12, and 16 weeks. Lacrimal gland (LG) infiltrating lymphocytes were characterized with flow cytometry. Tear epidermal growth factor (EGF) concentration was measured with enzyme-linked immunosorbent assay (ELISA). Quantitative polymerase chain reaction (PCR) evaluated T-cell-related cytokines in LGs. Serum autoantibodies against M3R in LG lysates were detected with Western blot. RESULTS: γDKO LG showed lower lymphocytic infiltration at 8 weeks than in the CD25KO parental strain (˜20% versus ˜60%, respectively), which increased to CD25KO levels at 16 weeks. Flow-cytometry analysis showed an increase in CD4+ and CD8+ T cells with aging in γDKO LG, similar to that in CD25KO. γDKO had lower levels of interleukin (IL)-17A, transforming growth-factor (TGF)-ß1, IL-21, and CCL20, and higher IL-1ß and IL-13 mRNA transcripts in the LG than in the parental CD25KO strain. Autoantibodies to M3R were observed in both strains and significantly increased with aging in both strains. CD25KO mice had very low tear EGF concentrations at all ages, whereas the ear EGF concentration in γDKO mice significantly decreased with aging and inversely correlated with the presence of M3R autoantibodies and the degree of LG CD4 and CD8+ T-cell infiltration. CONCLUSIONS: The deletion of IFN-γ in the CD25KO mice strain delays glandular destruction and preserves glandular function. M3R autoantibodies increased with aging in both the γDKO and the CD25KO strains. The decrease in LG function in γDKO correlated with the degree of T-cell infiltration and the presence of M3R autoantibodies.

NK cells promote Th-17 mediated corneal barrier disruption in dry eye.

BACKGROUND: The conjunctiva contains a specialized population of lymphocytes that reside in the epithelium, named intraepithelial lymphocytes (IEL). METHODOLOGY/PRINCIPAL FINDINGS: Here we characterized the IEL population prior to and after experimental desiccating stress (DS) for 5 or 10 days (DS5, DS10) and evaluated the effect of NK depletion on DS. The frequency of IELs in normal murine conjunctiva was CD3(+)CD103(+) (~22%), CD3(+)γδ(+) (~9.6%), CD3(+)NK(+) (2%), CD3(-)NK(+) (~4.4%), CD3(+)CD8α (~0.9%), and CD4 (~0.6%). Systemic depletion of NK cells prior and during DS led to a decrease in the frequency of total and activated DCs, a decrease in T helper-17(+) cells in the cervical lymph nodes and generation of less pathogenic CD4(+)T cells. B6.nude recipient mice of adoptively transferred CD4(+)T cells isolated from NK-depleted DS5 donor mice showed significantly less corneal barrier disruption, lower levels of IL-17A, CCL20 and MMP-3 in the cornea epithelia compared to recipients of control CD4(+)T cells. CONCLUSIONS/SIGNIFICANCE: Taken together, these results show that the NK IELs are involved in the acute immune response to desiccation-induced dry eye by activating DC, which in turn coordinate generation of the pathogenic Th-17 response.

Disruption of TGF-ß signaling improves ocular surface epithelial disease in experimental autoimmune keratoconjunctivitis sicca.

BACKGROUND: TGF-ß is a pleiotropic cytokine that can have pro- or anti-inflammatory effects depending on the context. Elevated levels of bioactive TGF-ß1 in tears and elevated TGF-ß1mRNA transcripts in conjunctiva and minor salivary glands of human Sjögren's Syndrome patients has also been reported. The purpose of this study was to evaluate the response to desiccating stress (DS), an experimental model of dry eye, in dominant-negative TGF-ß type II receptor (CD4-DNTGFßRII) mice. These mice have a truncated TGF-ß receptor in CD4(+) T cells, rendering them unresponsive to TGF-ß. METHODOLOGY/PRINCIPAL FINDINGS: DS was induced by subcutaneous injection of scopolamine and exposure to a drafty low humidity environment in CD4-DNTGFßRII and wild-type (WT) mice, aged 14 weeks, for 5 days. Nonstressed (NS) mice served as controls. Parameters of ocular surface disease included corneal smoothness, corneal barrier function and conjunctival goblet cell density. NS CD4-DNTGFßRII at 14 weeks of age mice exhibited a spontaneous dry eye phenotype; however, DS improved their corneal barrier function and corneal surface irregularity, increased their number of PAS+ GC, and lowered CD4(+) T cell infiltration in conjunctiva. In contrast to WT, CD4-DNTGFßRII mice did not generate a Th-17 and Th-1 response, and they failed to upregulate MMP-9, IL-23, IL-17A, RORγT, IFN-γ and T-bet mRNA transcripts in conjunctiva. RAG1KO recipients of adoptively transferred CD4+T cells isolated from DS5 CD4-DNTGFßRII showed milder dry eye phenotype and less conjunctival inflammation than recipients of WT control. CONCLUSIONS/SIGNIFICANCE: Our results showed that disruption of TGF-ß signaling in CD4(+) T cells causes paradoxical improvement of dry eye disease in mice subjected to desiccating stress.

Desiccating stress induces CD4+ T-cell-mediated Sjögren's syndrome-like corneal epithelial apoptosis via activation of the extrinsic apoptotic pathway by interferon-γ.

We investigated the role of CD4(+) T-cell-produced interferon (IFN)-γ on corneal epithelial apoptosis in a murine desiccating stress (DS) model that resembles Sjögren's syndrome. The DS model was generated in C57BL/6 (B6) and B6 IFN-γ-knockout (B6γKO) mice. Adoptive transfer of CD4(+) T cells from DS-exposed donor to recombination activating gene (RAG)-1(-/-) recipient mice and topical neutralization of IFN-γ were performed to determine whether IFN-γ produced by pathogenic CD4(+) T cells promotes corneal epithelial apoptosis. Apoptosis in corneal epithelia was assessed by evaluating the expression and activity of caspases 3, 8, and 9. The activation of caspase-8 mediated increased corneal epithelial apoptosis in B6 mice after DS, and this was exacerbated by subconjunctival IFN-γ injection. B6γKO mice were resistant to DS-induced apoptosis; however, B6γKO mice receiving IFN-γ developed apoptosis similar to that observed in B6 wild-type mice. Adoptive transfer of CD4(+) T cells from donors subjected to DS increased corneal epithelial apoptosis via activation of caspase-8 in recipients, similar to that in the donor mice. Topical neutralization of IFN-γ in adoptive transfer recipients decreased corneal epithelial apoptosis. DS, IFN-γ administration, or CD4(+) T-cell adoptive transfer had no effect on the expression and activation of the intrinsic apoptosis mediator, caspase-9. CD4(+) T-cell-produced IFN-γ plays a pivotal role in DS-induced corneal epithelial apoptosis via activation of the extrinsic apoptotic pathway.