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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 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.
>>
>>             ###
>>