>> *Thesis Defense Announcement >> To: The George Mason University Community* >> >> *Candidate: John R. Grimsley >> Program: Master of Science in Biology >> * >> *Date: Friday July 22, 2011 >> Time: 11:00 a.m. >> Place: George Mason University, Prince William campus >> Bull Run Hall, Room 246 >> >> Thesis Chair: Dr. Geraldine Grant >> >> Title: **"The Role of* *Krüppel Like Factor 4 in Idiopathic Pulmonary Fibrosis**"* >> >> >> >> A copy of the thesis is on reserve in the Johnson Center Library, >> Fairfax campus. The thesis will not be read at the meeting, but >> should be read in advance. >> >> All members of the George Mason University community are invited to >> attend. >> >> >> ABSTRACT: >> >> Idiopathic Pulmonary Fibrosis (IPF) is a fatal >> interstitial lung disease (ILD) with no known cause and >> characterized by a progressive build up fibrotic tissue >> in the diseased lung. Krüppel-Like Factor 4 (KLF4), a >> transcription factor with key roles in the cell cycle, >> cellular differentiation and development, was found to be >> over-expressed in primary IPF fibroblasts. In this study >> we sought to investigate the potential role of KLF4 in >> IPF by investigating the effect of its over-expression on >> fibroblast differentiation and proliferation status in >> the normal human pulmonary fibroblasts cell line, MRC5. >> In addition, we investigated the localization of KLF4 in >> vivo using normal and IPF tissue (LTRC). The in vivo >> localization of KLF4 in IPF and normal tissue was >> confirmed by double-Immunohistochemistry (IHC) in >> combination with either alpha-SMA or PCNA (Abcam). KLF4 >> over-expression in MRC5 cells was achieved using a >> doxycycline inducible lentiviral system (Addgene) and >> confirmed by quantitative real time PCR (Q-RTPCR) and >> western blot. The effect of KLF4 over-expression on >> markers of proliferation and activation was monitored by >> Q-RTPCR. Localization of KLF4 in the IPF lung was >> observed on the perimeter of the fibroblastic foci and in >> the parenchyma in areas of advanced fibrosis, however, >> absent with in the fibrotic foci. Co-localization of >> KLF4 and PCNA was observed, however, alpha-SMA and KLF4 >> were not observed to co-localize. Following KLF4 >> induction in vitro a 6-fold increase in KLF4 mRNA and a >> 3-fold increase in protein were observed. A decrease in >> alpha-SMA expression (2-fold) at both the gene and >> protein level was detected in addition to an increase in >> collagen 1A1 (3-fold) mRNA. A decrease in all >> proliferation markers selected: PCNA, cyclin D1 and >> p21was observed, in addition to p53. The in vivo >> distribution of KLF4, suggests may be involved in the >> advancement of fibrosis and expansion of the foci. In >> vitro over-expression studies in MRC5 cells revealed a >> profoundly negative affected on the cell cycle which >> appears to be in contrast of IPF, however, in keeping >> with KLF4's dual roles of tumor suppressor and tumor >> promoter. Of particular interest was KLF4 >> over-expression resulted in an increase in collagen >> production, the main ECM component of IPF. KLF4 operated >> in a strongly context dependant manner, and IPF is a >> particularly context driven disease where the ECM acts >> almost as another pathogenic entity. Therefore, while >> direct comparison between in vivo IPF fibroblasts and in >> vitro MRC5 cells cannot be made, these data indicates a >> potential role for KLF4 in the pathogenesis of IPF. >> Further characterizations of this role through >> experimentation in primary adult IPF fibroblasts are >> warranted. >> >> ### >>