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> *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 257
>  
> 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.
>
>             ###
>