CD4⁺CD25⁺ regulatory T cells (T regs) play a major role in the maintenance of self-tolerance and immune suppression, although the mechanisms controlling T reg development and suppressor function remain incompletely understood. Herein, we provide evidence that Kruppel-like factor 10 (KLF10/TIEG1) constitutes an important regulator of T regulatory cell suppressor function and CD4⁺CD25⁻ T cell activation through distinct mechanisms involving transforming growth factor (TGF)-β1 and Foxp3. KLF10 overexpressing CD4⁺CD25⁻ T cells induced both TGF-β1 and Foxp3 expression, an effect associated with reduced T-Bet (Th1 marker) and Gata3 (Th2 marker) mRNA expression. Consistently, KLF10^−/− CD4⁺CD25⁻ T cells have enhanced differentiation along both Th1 and Th2 pathways and elaborate higher levels of Th1 and Th2 cytokines. Furthermore, KLF10^−/− CD4⁺CD25⁻ T cell effectors cannot be appropriately suppressed by wild-type T regs. Surprisingly, KLF10^−/− T reg cells have reduced suppressor function, independent of Foxp3 expression, with decreased expression and elaboration of TGF-β1, an effect completely rescued by exogenous treatment with TGF-β1. Mechanistic studies demonstrate that in response to TGF-β1, KLF10 can transactivate both TGF-β1 and Foxp3 promoters, implicating KLF10 in a positive feedback loop that may promote cell-intrinsic control of T cell activation. Finally, KLF10^−/− CD4⁺CD25⁻ T cells promoted atherosclerosis by ∼2-fold in ApoE^−/−/scid/scid mice with increased leukocyte accumulation and peripheral pro-inflammatory cytokines. Thus, KLF10 is a critical regulator in the transcriptional network controlling TGF-β1 in both CD4⁺CD25⁻ T cells and T regs and plays an important role in regulating atherosclerotic lesion formation in mice.

Purpose: The purpose of this work was to define the timing and magnitude of scleral contact lens settling, the factors influencing settling, and to examine whether the amount of apical clearance has an impact on clinical performance or is associated with hypoxia-induced corneal changes. Methods: Eleven patients (22 eyes) with keratoconus were fitted with a mini-scleral lens (Esclera, Brazil). Three different lenses with successively greater sagittal depths were applied to achieve 3 levels of initial apical clearance: 100 to 200 μm (low), 200 to 300 μm (medium), and greater than 300 μm (high). Corneal apical clearance was measured at 15 min, 1, 2, 4, 6, and 8 hr with optical coherence tomography (OCT). Central corneal thickness was measured with OCT and Pentacam, in the morning and immediately after removal of the contact lens. Results: Mean settling was 26.8±18.8 μm (42.7%) at 1 hr, 39.5±26.5 μm (62.9%) at 2 hr, 50.7±31.6 μm (80.8%) at 4 hr, 57.4±34.6 μm (91.4%) at 6 hr, and 62.8±38.4 μm (100%) at 8 hr. Settling rate was significantly lower in low apical clearance group (P=0.01). The smaller diameter lenses settled more (P=0.03). There was a slight statistically significant increase of 1.3% in central corneal thickness measured with OCT (P=0.03). Central corneal thickness measured with Pentacam at three locations increased slightly (P=0.001). Settling showed significant intrasubject and intersubject variations. The amount of corneal swelling and comfort scores did not differ significantly according to apical clearance. Conclusions: The average amount of settling was 62.8 μm after 8 hr, 80% of which occurred during the first 4 hr. Slight corneal swelling (1.3%) occurred after 8 hr of wear.

Emerging evidence demonstrates that proangiogenic cells (PACs) originate from the BM and are capable of being recruited to sites of ischemic injury where they contribute to neovascularization. We previously determined that among hematopoietic progenitor stem cells, common myeloid progenitors (CMPs) and granulocyte-macrophage progenitor cells (GMPs) differentiate into PACs and possess robust angiogenic activity under ischemic conditions. Herein, we report that a TGF-β1–responsive Krüppel- like factor, KLF10, is strongly expressed in PACs derived from CMPs and GMPs, ∼ 60-fold higher than in progenitors lacking PAC markers. KLF10^−/− mice present with marked defects in PAC differentiation, function, TGF-β responsiveness, and impaired blood flow recovery after hindlimb ischemia, an effect rescued by wild-type PACs, but not KLF10^−/− PACs. Overexpression studies revealed that KLF10 could rescue PAC formation from TGF-β1^+/− CMPs and GMPs. Mechanistically, KLF10 targets the VEGFR2 promoter in PACs which may underlie the observed effects. These findings may be clinically relevant because KLF10 expression was also found to be significantly reduced in PACs from patients with peripheral artery disease. Collectively, these observations identify TGF-β1 signaling and KLF10 as key regulators of functional PACs derived from CMPs and GMPs and may provide a therapeutic target during cardiovascular ischemic states.

Clinical studies using bone marrow–derived proangiogenic cells (PACs) have demonstrated modest improvements of function and/or perfusion of ischemic myocardium or skeletal muscle. Because the identities of these PACs and their functional ability to promote neovascularization remain poorly understood, it is possible that a subset of robust PACs exists but is obscured by the heterogeneous nature of this cell population. Herein, we found that common myeloid progenitors (CMPs) and granulocyte-macrophage progenitors (GMPs) preferentially differentiate into PACs compared with megakaryocyte-erythrocyte progenitors, hematopoietic stem cells, and common lymphoid progenitors. In vivo hindlimb ischemia studies and Matrigel plug assays verified the enhanced neovascularization properties uniquely associated with PACs derived from CMPs and GMPs. Taken together, these observations identify CMPs and GMPs as key bone marrow progenitors for optimal PAC function in vitro and in vivo and provide a foundation for novel therapeutic approaches to modulate angiogenesis.

Purpose: Most of the statistical tests used in significance testing are based on the assumption that each data entry is independent from other entries, however, we observe that in many articles researchers include data from 2 eyes as independent variables while performing these statistical tests. The aim of this study was to formally survey the prevalence of the above-mentioned “double-organ bias” in randomized controlled trials (RCT) of glaucoma. Materials and Methods: We did a PubMed search with the terms “glaucoma” and limitations “Humans” and “Randomized Controlled Trials” in 15 highest-impact-factor ophthalmology journals between November 2002 and November 2012. We only included RCTs published as an original article, where the aim was treating glaucoma. Two independent observers (M.K. and A.S.E.) read through each article and classified the articles according to treatment modality (medical, laser, or surgical) and presence of double-organ bias. Results: The PubMed search yielded 270 articles. A total of 130 articles qualified for the survey. Eighty-five of the RCTs were medical studies, 11 were laser studies, and 34 studies evaluated the outcome of a surgical procedure. In 17 of the 130 articles (13.1%), double-organ bias was found. Prevalence of the double-organ bias was not significantly different between medical (12.9%), laser (14.7%), and surgical (9.1%) studies. Conclusion: Double-organ bias was observed around 13.1% of the published RCTs, leading to inaccurate statistical testing.