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