379
or peripheral blood carries prognostic signifi cance for cancer patients. Quite intriguingly, several studies have provided evidence for active keratin involvement in cancer
cell invasion and metastasis, as well as in treatment responsiveness, and have set the
foundation for further exploration of the role of keratins as multifunctional regulators
of epithelial tumorigenesis,” (Karantza 2011 ).
Scientifi c data on isolation, purifi cation, and characterization of keratin proteins
of hair and wool fi bers origin obtained during over the past century are used as the
platform for the development of a keratin-based biomaterials today (Rouse and
Van Dyke 2010 ). The fi rst study using a keratin biomaterial was published in
1982. Noishiki and colleagues coated a heparinized keratin derivative onto a polymer stent and implanted it into a dog for more than 200 days without thrombosis
(Noishiki et al. 1982 ). Keratin coatings and fi lms, keratin-chitosan fi lms, compression
molded keratin fi lms, keratin-hydroxyapatite sponges, modifi ed keratin sponges
containing growth factors, pure keratin scaffolds, and keratin-coated hydroxyapatite have all been developed and investigated during last 30 years (see for review
Hill et al. 2010 ).
However, in contrast to keratins from human and terrestrial mammals (e.g.
sheep) as well as feather keratins, little attention was paid to marine keratins of
reptilians and fi sh origin. The most recent works on keratins are from marine turtles,
and were published by Lorenzo Alibardi and co-workers. Fish keratins, including
those from sharks (Schaffeld et al. 1998 , 2001 , 2004 ), were mostly investigated in
terms of their molecular biology rather than for their bioinspirational potential (see
for review Markl and Schechter 1998 ; Zimek et al. 2003 ; Schaffeld and Markl 2004 ;
Krushna Padhi et al. 2006 ). Only fi sh with keratin-like fi brillar proteins, such as
those from hagfi sh slime, have been intensively investigated in the Lab of Douglas
Fudge as biological materials (represented below). The third group of marine
keratins is related to cetacean keratins, mostly to baleen, which are also discussed
in this chapter.
Marine Reptilian Keratins The heavily keratinised nature of the carapace and
plastron of aquatic chelonians provides not only an impervious barrier to the environment, but a considerable degree of protection against attack. Such protection
increases with age as the keratinised layer simultaneously thickens and hardens.
The characteristic ridged pattern of the individual scales becomes more marked
with age and, as in the newly emerged hatchling, is more pronounced over the carapace. Unlike the epidermis of many aquatic vertebrates, the chelonian shell is not
covered with a layer of mucus (Fig. 11.1 ), which serves to reduce the frictional drag
in water. It is customary, however, for the chelonian shell to acquire an overgrowth
of algae. Although the ridges may have no signifi cance in their own right, they may
subserve a similar function by providing a suitable site at which mucous-secreting
algae could anchor (Solomon et al. 1986 ).
Turtle’s carapace is not only the one place of keratins location. For example, the
peculiarly specialized esophagus of the Pacifi c ridley turtle ( Lepidochelys olivacea )
also possesses keratin. As described by Yoshie and Honma ( 1976 ), the esophagus is
distinguished by a specialized remarkably keratinized squamous epithelium, and its
11 Marine Keratins
or peripheral blood carries prognostic signifi cance for cancer patients. Quite intriguingly, several studies have provided evidence for active keratin involvement in cancer
cell invasion and metastasis, as well as in treatment responsiveness, and have set the
foundation for further exploration of the role of keratins as multifunctional regulators
of epithelial tumorigenesis,” (Karantza 2011 ).
Scientifi c data on isolation, purifi cation, and characterization of keratin proteins
of hair and wool fi bers origin obtained during over the past century are used as the
platform for the development of a keratin-based biomaterials today (Rouse and
Van Dyke 2010 ). The fi rst study using a keratin biomaterial was published in
1982. Noishiki and colleagues coated a heparinized keratin derivative onto a polymer stent and implanted it into a dog for more than 200 days without thrombosis
(Noishiki et al. 1982 ). Keratin coatings and fi lms, keratin-chitosan fi lms, compression
molded keratin fi lms, keratin-hydroxyapatite sponges, modifi ed keratin sponges
containing growth factors, pure keratin scaffolds, and keratin-coated hydroxyapatite have all been developed and investigated during last 30 years (see for review
Hill et al. 2010 ).
However, in contrast to keratins from human and terrestrial mammals (e.g.
sheep) as well as feather keratins, little attention was paid to marine keratins of
reptilians and fi sh origin. The most recent works on keratins are from marine turtles,
and were published by Lorenzo Alibardi and co-workers. Fish keratins, including
those from sharks (Schaffeld et al. 1998 , 2001 , 2004 ), were mostly investigated in
terms of their molecular biology rather than for their bioinspirational potential (see
for review Markl and Schechter 1998 ; Zimek et al. 2003 ; Schaffeld and Markl 2004 ;
Krushna Padhi et al. 2006 ). Only fi sh with keratin-like fi brillar proteins, such as
those from hagfi sh slime, have been intensively investigated in the Lab of Douglas
Fudge as biological materials (represented below). The third group of marine
keratins is related to cetacean keratins, mostly to baleen, which are also discussed
in this chapter.
Marine Reptilian Keratins The heavily keratinised nature of the carapace and
plastron of aquatic chelonians provides not only an impervious barrier to the environment, but a considerable degree of protection against attack. Such protection
increases with age as the keratinised layer simultaneously thickens and hardens.
The characteristic ridged pattern of the individual scales becomes more marked
with age and, as in the newly emerged hatchling, is more pronounced over the carapace. Unlike the epidermis of many aquatic vertebrates, the chelonian shell is not
covered with a layer of mucus (Fig. 11.1 ), which serves to reduce the frictional drag
in water. It is customary, however, for the chelonian shell to acquire an overgrowth
of algae. Although the ridges may have no signifi cance in their own right, they may
subserve a similar function by providing a suitable site at which mucous-secreting
algae could anchor (Solomon et al. 1986 ).
Turtle’s carapace is not only the one place of keratins location. For example, the
peculiarly specialized esophagus of the Pacifi c ridley turtle ( Lepidochelys olivacea )
also possesses keratin. As described by Yoshie and Honma ( 1976 ), the esophagus is
distinguished by a specialized remarkably keratinized squamous epithelium, and its
11 Marine Keratins