contained in each Raman spectrum provides knowledge about the structure and
chemical composition of the studied specimens. A number of advantages of this
analytical label-free technique make it more and more often used for studying
biological and biomedical systems. Due to the small scattering cross section for
water, the aqueous environment, convenient for tissue and cell measurements, can
be used. The high resolving power of Raman microscopy makes possible monitoring changes in the content of biocomponents in the subcellular scale and
determining their distribution in the organelles and the main cellular compartments.
All above-mentioned advantages make Raman microscopy an excellent tool for
investigating cellular processes and for future diagnostics of diseases [63].
Nowadays, the prevention and treatment of lifestyle diseases, such as
atherosclerosis or diabetes, are extremely hot topics and challenges for modern
medicine. A large amount of work is devoted to new, innovative diagnostic
methods and treatment regimens. However, future progress seems impossible
without deeper knowledge about mechanisms related to onset and development of
these pathologies. It is postulated that most of the cardiovascular diseases start with
endothelial dysfunction. The endothelium is a monolayer of cells, a barrier between
the blood and the inner part of the vessel and a very active regulative organ.
Considering its location, it is an integral and important structure in maintaining the
proper functioning of the vessel wall and the entire circulatory system [64]. At the
same time, it is extremely susceptible to influence pathological factors, and thus
endothelial cells are a very convenient and suitable model for in vitro studies of
development of circulatory system pathologies.
6.2.1 Characteristics of Endothelial Cell Cultures
Endothelial cells in vitro enable studying various physiological and pathological
processes and can be divided into three groups: primary cells, prolonged life cells,
and cells from immortalized cell lines [65]. The first one refers to cells directly
isolated from the tissue using enzymatic or mechanical methods. However,
endothelial cells are diverse. They exhibit morphological, physiological, and phenotypic differences resulting from the location in the arterial tree as well as due to
their origin, i.e., arteries or veins [64]. Their heterogeneous nature is observed within
the living organism in vivo as well as in in vitro cultures [66]. It is generally
accepted that primary cells are most suitable for studying biological processes that
are related to specific in vivo systems; however, the lifespan of such cells is very
limited. Individual variability, short lifetime, and time-consuming primary cell isolation have prompted researchers to modify primary cultures. A successfully used
approach is introduction of foreign DNA/RNA, i.e., large T antigen of SV40 virus
[67] into cells by genetic transfection or mutation, or artificial modifications, i.e.,
fusion with cancer cells. Resulting cells have a stable, homogenous phenotype and
genotype, and can also be cultured almost indefinitely [65]. In the group constituting
the immortalized, commercially available cells, subgroups according to their
6 Small and Large Molecules Investigated by Raman Spectroscopy
171
chemical composition of the studied specimens. A number of advantages of this
analytical label-free technique make it more and more often used for studying
biological and biomedical systems. Due to the small scattering cross section for
water, the aqueous environment, convenient for tissue and cell measurements, can
be used. The high resolving power of Raman microscopy makes possible monitoring changes in the content of biocomponents in the subcellular scale and
determining their distribution in the organelles and the main cellular compartments.
All above-mentioned advantages make Raman microscopy an excellent tool for
investigating cellular processes and for future diagnostics of diseases [63].
Nowadays, the prevention and treatment of lifestyle diseases, such as
atherosclerosis or diabetes, are extremely hot topics and challenges for modern
medicine. A large amount of work is devoted to new, innovative diagnostic
methods and treatment regimens. However, future progress seems impossible
without deeper knowledge about mechanisms related to onset and development of
these pathologies. It is postulated that most of the cardiovascular diseases start with
endothelial dysfunction. The endothelium is a monolayer of cells, a barrier between
the blood and the inner part of the vessel and a very active regulative organ.
Considering its location, it is an integral and important structure in maintaining the
proper functioning of the vessel wall and the entire circulatory system [64]. At the
same time, it is extremely susceptible to influence pathological factors, and thus
endothelial cells are a very convenient and suitable model for in vitro studies of
development of circulatory system pathologies.
6.2.1 Characteristics of Endothelial Cell Cultures
Endothelial cells in vitro enable studying various physiological and pathological
processes and can be divided into three groups: primary cells, prolonged life cells,
and cells from immortalized cell lines [65]. The first one refers to cells directly
isolated from the tissue using enzymatic or mechanical methods. However,
endothelial cells are diverse. They exhibit morphological, physiological, and phenotypic differences resulting from the location in the arterial tree as well as due to
their origin, i.e., arteries or veins [64]. Their heterogeneous nature is observed within
the living organism in vivo as well as in in vitro cultures [66]. It is generally
accepted that primary cells are most suitable for studying biological processes that
are related to specific in vivo systems; however, the lifespan of such cells is very
limited. Individual variability, short lifetime, and time-consuming primary cell isolation have prompted researchers to modify primary cultures. A successfully used
approach is introduction of foreign DNA/RNA, i.e., large T antigen of SV40 virus
[67] into cells by genetic transfection or mutation, or artificial modifications, i.e.,
fusion with cancer cells. Resulting cells have a stable, homogenous phenotype and
genotype, and can also be cultured almost indefinitely [65]. In the group constituting
the immortalized, commercially available cells, subgroups according to their
6 Small and Large Molecules Investigated by Raman Spectroscopy
171