title: LIF-JAK1-STAT3 signaling delays contact inhibition of human corneal endothelial cells.
abstract: Human corneal endothelial cells (HCECs) responsible for corneal transparency have limited proliferative capacity in vivo because of "contact-inhibition." This feature has hampered the ability to engineer HCECs for transplantation. Previously we have reported an in vitro model of HCECs in which contact inhibition was re-established at Day 21, even though cell junction and cell matrix interaction were not perturbed during isolation. Herein, we observe that such HCEC monolayers continue to expand and retain a normal phenotype for 2 more weeks if cultured in a leukemia inhibitory factor (LIF)-containing serum-free medium. Such expansion is accompanied initially by upregulation of Cyclin E2 colocalized with nuclear translocation of phosphorylated retinoblastoma tumor suppressor (p-Rb) at Day 21 followed by a delay in contact inhibition through activation of LIF-Janus kinase1 (JAK1)-signal transducer and activator of transcription 3 (STAT3) signaling at Day 35. The LIF-JAK1-STAT3 signaling is coupled with upregulation of E2F2 colocalized with nuclear p-Rb and with concomitant downregulation of p16(INK4a), of which upregulation is linked to senescence. Hence, activation of LIF-JAK1-STAT3 signaling to delay contact inhibition can be used as another strategy to facilitate engineering of HCEC grafts to solve the unmet global shortage of corneal grafts.
authors.affiliation: a Department of Ophthalmology; Union Hospital; Tongji Medical College ; Huazhong University of Science and Technology ; Wuhan , China.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Scheffer C G
authors.initials: SC
authors.lastname: Tseng
authors.forename: Ming-Chang
authors.initials: MC
authors.lastname: Zhang
authors.forename: Szu-Yu
authors.initials: SY
authors.lastname: Chen
authors.forename: Sean
authors.initials: S
authors.lastname: Tighe
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Lu
authors.forename: Ying-Ting
authors.initials: YT
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D003260:Contact Inhibition / Q000187:drug effects; D003315:Cornea / Q000166:cytology*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism; D050703:E2F2 Transcription Factor / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D006801:Humans; D053613:Janus Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D053605:Leukemia Inhibitory Factor / Q000378:metabolism / Q000494:pharmacology*; D008875:Middle Aged; D034741:RNA, Small Interfering / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects; D055815:Young Adult
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16; D050703:E2F2 Transcription Factor; D053605:Leukemia Inhibitory Factor; D034741:RNA, Small Interfering; D016160:Retinoblastoma Protein; D050796:STAT3 Transcription Factor; D016222:Fibroblast Growth Factor 2; D053613:Janus Kinase 1
keywords: BMP, bone morphogenetic protein; BrdU, bromodeoxyuridine; CDK, cyclin-dependent kinase; CKI, cyclin-dependent kinase inhibitors; DMEM, Dulbecco's modified Eagle's medium; E2F2; EDTA, ethylenediaminetetraacetic acid; EGF, epidermal growth factor; EMT, endothelial mesenchymal transition; ESC, embryonic stem cell; FBS, fetal bovine serum; GAPDH, glyceraldehyde-3- phosphate dehydrogenase; HBSS, Hanks’ balanced salt solution; HCEC, human corneal endothelial cell; ID, inhibitor of differentiation; ITS, insulin-transferrin-sodium selenite; JAK, Janus kinase; JAK1; LEF1, lymphoid enhancer-binding factor 1; LIF; LIF, leukemia inhibitory factor; MESCM, modified embryonic stem cell medium; NC, neural crest; NFkB, nuclear factor kappa-light-chain-enhancer of activated B cells; PBS, phosphate-buffered saline; RPE, retinal pigment epithelial cells; Rb, retinoblastoma tumor suppressor; SHEM, supplemental hormonal epithelial medium; STAT3; STAT3, signal transducer and activator of transcription 3; ZO-1, Zona occludens protein 1; bFGF, basic fibroblast growth factor; contact inhibition; corneal endothelium; iPSCs, induced pluripotent stem cells; p120, p120 catenin; p16INK4a; proliferation; scRNA, scramble RNA; siRNA, small interfering ribonucleic acid