@article{Fischer2020,
   author = {Fischer, T;Klinger, A;von Smolinski, D;Orzekowsky-Schroeder, R;Nitzsche, F;Bölke, T;Vogel, A;Hüttmann, G and Gebert, A},
   title = {High-resolution imaging of living gut mucosa: lymphocyte clusters beneath intestinal M cells are highly dynamic structures},
   journal = {Cell and Tissue Research},
   pages = {1-8},
   ISSN = {1432-0878},
   url = {https://doi.org/10.1007/s00441-020-03167-z},
   year = {2020},
   type = {Journal Article}
}

@article{Vogel-2019-1,
   author = {Fischer, T;Klinger, A;Smolinski, D von;Orzekowsky-Schroeder, R;Nitzsche, F;Vogel, A;Hüttmann, G and Gebert, A},
   title = {High-resolution imaging of the living gut mucosa: lymphocyte clusters beneath intestinal M cells are highly dynamic structures},
   journal = {Cell and Tissue Research},
   ISSN = {0302-766X (Print) 
1432-0878 (Online)},
   year = {2019},
   type = {Journal Article}
}

@article{Klinger2017,
   author = {Klinger, A. and Krapf, L. and Orzekowsky-Schroeder, R. and Koop, N. and Vogel, A. and Huttmann, G.},
   title = {Intravital autofluorescence 2-photon microscopy of murine intestinal mucosa with ultra-broadband femtosecond laser pulse excitation: image quality, photodamage, and inflammation},
   journal = {J Biomed Opt},
   volume = {20},
   number = {11},
   pages = {116001},
   ISSN = {1083-3668},
   DOI = {10.1117/1.jbo.20.11.116001},
   year = {2015},
   type = {Journal Article}
}

@misc{Miura2013,
   author = {Miura, Y and Huettmann, G and Orzekowsky-Schroeder, R and Steven, P and Szaszák, M and Koop, N and Brinkmann, R },
   title = {Two-photon Microscopy and Fluorescence Lifetime Analysis of Lipid Peroxidation Product in Photoreceptor Outer Segment and in Retinal Pigment Epithelial Cell},
   publisher = {ARVO Meeting Abstracts},
   month = {March 26, 2012 },
   url = {http://www.abstractsonline.com/Plan/ViewAbstract.aspx?sKey=57630548-893d-4e45-9ddc-b6f547dd4ff0&cKey=d08a30bc-fe98-40a2-8a1c-1b171e4becd3&mKey=f0fce029-9bf8-4e7c-b48e-9ff7711d4a0e},
   year = {2013},
   type = {Poster}
}

@article{Miura2013,
   author = {Miura, Y. and Huettmann, G. and Orzekowsky-Schroeder, R. and Steven, P. and Szaszak, M. and Koop, N. and Brinkmann, R.},
   title = {Two-Photon Microscopy and Fluorescence Lifetime Imaging of Retinal Pigment Epithelial Cells under Oxidative Stress},
   journal = {Invest Ophthalmol Vis Sci},
   note = {Miura, Yoko
Huettmann, Gereon
Orzekowsky-Schroeder, Regina
Steven, Philipp
Szaszak, Marta
Koop, Norbert
Brinkmann, Ralf
ENG
2013/04/06 06:00
Invest Ophthalmol Vis Sci. 2013 Apr 4. pii: iovs.13-11808v1. doi: 10.1167/iovs.13-11808.},
   abstract = {PURPOSE: The aim of this study was to investigate the autofluorescence (AF) of the RPE with two-photon microscopy (TPM) and fluorescence lifetime imaging (FLIM) under normal and oxidative stress conditions. METHODS: Porcine RPE-choroid explants were used for investigation. The RPE-choroid tissue was preserved in a perfusion organ culture system. Oxidative stress was induced by laser photocoagulation with frequency-doubled Nd:YAG laser (532 nm) and by exposure to different concentrations (0, 1, 10 mM) of ferrous sulfate (FeSO4) for 1 hr. At indicated time points after exposure, the tissue was examined with TPM and FLIM. Intracellular reactive oxygen species around the photocoagulation lesion were detected with chloromethyl-2'7'-dichlorofluorescein diacetate (CM-H2DCFDA). Melanosomes were isolated from RPE cells and its fluorescence properties were investigated under normal and oxidized conditions. RESULTS: Under normal condition, AF in RPE cells with TPM is mostly originated from melanosomes, which has a very short fluorescence lifetime (FLT) (mean=117 ps). Under oxidative stress induced by laser irradiation and FeSO4 exposure, bright granular AF appears inside and around RPE cells, whose FLT is significantly longer (mean=1388 ps) than the FLT of the melanosome-AF. Excitation and emission peaks are found at 710-750 nm and 450-500 nm, respectively. Oxidative stress increases the fluorescence intensity of the melanosomes but does not change their FLT. CONCLUSION: TPM reveals acute oxidative stress-induced bright AF granules inside and around RPE cells which can be clearly discriminated from melanosomes by FLIM. TPM combined with FLIM is a useful tool of live-cell analysis to investigate functional alterations of the RPE.},
   year = {2013}
}

@article{Szaszak,
   author = {Szaszák, Márta and Steven, Philipp and Shima, Kensuke and Orzekowsky-Schröder, Regina and Hüttmann, Gereon and König, Inke R. and Solbach, Werner and Rupp, Jan},
   title = {Fluorescence Lifetime Imaging Unravels <italic>C. trachomatis</italic> Metabolism and Its Crosstalk with the Host Cell},
   journal = {PLoS Pathog},
   volume = {7},
   number = {7},
   pages = {e1002108},
   abstract = {<title>Author Summary</title> <p>Separate analysis of host and pathogen metabolic changes in intracellular <italic>C. trachomatis</italic> infections is arduous and has not been comprehensively realized so far. A more detailed understanding about the metabolic activity and needs of <italic>C. trachomatis</italic> and its specific interactions with the host cell would be the basis for the development of novel treatment strategies. We therefore applied fluorescence lifetime imaging (FLIM) of the metabolic coenzymes NAD(P)H using two-photon microscopy to directly visualize metabolic changes of host cells and pathogens in living cells. NAD(P)H fluorescence was detected both on the chlamydial inclusion membrane and inside the inclusion. Interestingly, changes in chlamydial growth and progeny induced by glucose starvation and IFN? treatment were directly linked to significant changes of the NAD(P)H fluorescence lifetimes inside the inclusions. Furthermore, measurement of the NAD(P)H fluorescence lifetime in the host cell nucleus revealed that infected cells were programmed for starvation during the metabolically active phase of intracellular chlamydial growth. Our findings highlight for the first time a direct interaction between host and pathogen metabolism in intracellular bacterial infections that exceeds sole competition for nutrients. In conclusion, fluorescence lifetime imaging of NAD(P)H by two-photon microscopy enables real-time analysis of metabolic host-pathogen interactions in intracellular infections with high spatial and temporal resolution.</p>},
   year = {2011}
}

@article{Orzekowsky2011,
   author = {Orzekowsky-Schroeder, Regina and Klinger, Antje and Martensen, Bjorn and Blessenohl, Maike and Gebert, Andreas and Vogel, Alfred and Huttmann, Gereon},
   title = {In vivo spectral imaging of different cell types in the small intestine by two-photon excited autofluorescence},
   journal = {Journal of Biomedical Optics},
   volume = {16},
   number = {11},
   pages = {116025},
   keywords = {biological organs
biomedical optical imaging
cellular biophysics
fluorescence
laser applications in medicine
two-photon processes},
   year = {2011}
}

@inproceedings{Miura2010,
   author = {Miura, Y and Huettmann, G and Orzekowsky-Schroeder, R and Steven, P and Szaszák, M and Koop, N and Brinkmann, R},
   title = {Appearance of autofluorescence in RPE cells at the rim of photocoagulation},
   booktitle = {FLIM 2010 - Symposium "Fluorescence Lifetime Imaging of the Human Retina"},
   type = {Conference Proceedings},
Year = { 2010}
}

@inproceedings{Orzekowsky2010,
   author = {Orzekowsky-Schroeder, Regina and Klinger, Antje and Schuth, Anna and Freidank, Sebastian and Huttmann, Gereon and Gebert, Andreas and Vogel, Alfred},
   title = {Intravital real-time study of tissue response to controlled laser-induced cavitation using 500-ps UV laser pulses focused in murine gut mucosa under online dosimetry and spectrally resolved 2-photon microscopy},
   editor = {Daniel, L. Farkas and Dan, V. Nicolau and Robert, C. Leif},
   publisher = {SPIE},
   volume = {7568},
   pages = {756815},
url = { https://doi.org/10.1117/12.843102},
year = { 2010}

}