Tissue Engineering Course Application
The PTEI outreach education manual for tissue engineering can be utilized within
the context of a standard high school introductory biology curriculum by serving as a
platform for the introduction of a number of key biological concepts. Typically, biology
instructors follow a direct path through a standard text, covering mandated content
chapter by chapter, supplemented by suggested student activities meant to reinforce
content, key concepts, and science process. This strategy often fails to reinforce critical
connections between topics or concepts, and often does not provide a unifying theme or
application that might serve to accomplish that elusive goal. In addition, students are
rarely challenged to identify key questions that could serve to reveal underlying
connections or suggest potential applications resulting from their elucidation.
Introductory biology instructors often proceed up a perceived chain of
organizational complexity, and this is reinforced by many textbooks. Chapters on basic
chemistry, biochemistry lead to chapters on cell structure, organization, and physiology.
Cell processes such as energy metabolism, transcription, translation, and reproduction
often lead directly to genetics and applied DNA science. Throughout the sequence of the
central dogma (DNA—RNA—protein, or transcription-translation) and DNA science,
some teachers include a discussion of gene expression and perhaps its relationship to the
process of multicellular development. Generally, human anatomy and physiology is
addressed, if at all, late in the school year. For those that do include even a little human
anatomy and physiology, it is often addressed in the context of a comparative survey
among animal taxa. The concept of human health and biomedical research appears to be
most often addressed as interesting sidelights to, or applications of, the current life
science topic of study. Examples of this strategy include: abnormal gene function and its
relationship to inherited disease, microbes influence on human disease, and abnormal
cellular responses (or growth characteristics) leading to the progression of cancer. Tissue
engineering provides a forum that could enable teachers to readily reveal the connections
between many of these same basic content areas, with the added attraction of addressing
human biomedical concerns.
A curriculum employing tissue engineering as a unifying theme could address
much of the content covered in introductory life science by challenging students to
identify key questions and knowledge that might be required to aid people with
compromised tissue function. One such approach to the course might begin with a
familiar organizational theme. What is the composition of a human body? Basic
chemical concepts, along with biochemistry, might serve to begin the search for a means
to regenerate tissue. Higher order organization of these components naturally leads to a
discussion of cellular anatomy and physiology. An understanding of both cell structures
and physiologic processes can be identified as key components of the tissue regeneration
puzzle. Certainly, it is hoped that teachers and students would further recognize the need
to understand the organization and functionality of populations of cells. How do cells
organize? What types of bodily structures might result, and how are their functions
regulated? More subtle questions might involve the continuity of both structure and
function. For example, do cell populations change in a given tissue? Are cells
reproducing? Or dying? Do some cells change in form and function? How are these
changes in cell populations regulated? More basically, how did these tissues and inherent
dynamic processes come about? These questions address some of the key and most
researched questions in life science, as well as serving to offer a dramatic segue into the
realm of cell information processing.
The questions posed in the preceding paragraph, as well those questions
pertaining to multicellular development, cell replication, cell-cell (or tissue-tissue)
interaction, and even certain disease states, can be intimately related to the phenomena of
intracellular and extracellular information processing. At its root, the processes of DNA
replication, transcription, and translation determine cell structure, multicellular
development and organization, and tissue regulation. Thus, teachers can guide students
to this realization by posing these defining questions, or have students independently
generate such a list. For example, consider the fundamental question: How does the
multicellular human condition arise? Clearly, students should eventually come to
propose that it is not by chance. That is, cells are adhering to instructions or some form
of information. Explaining the nature of the information (DNA sequences and molecules
produced as a consequence of their ‘reading’) within this context provides a human focus
to the central dogma. However, students might be able to recognize more subtle
questions related to this standard explanation. Do all the cells of a particular human (or
developing embryonic human) possess the same DNA? What key experiments shed light
on this important question? If all cells of an embryo possess equivalent DNA, how do
cells assume different structures and functions? What influences differentiation? How is
the information passed from one generation to the next? Can information controlling
tissue development and organization be adversely affected, and what might be the
consequences of such disruption? Clearly, standard textbook material relating to the
central dogma can serve as the basis for the answers to many of these questions.
However, challenging students to define these key questions and to propose adequate
answers should allow them to make connections not often stressed in typical classrooms.
Once students come to realize that the DNA of embryonic cells is virtually
equivalent, teachers can then lead them to the phenomena of extracellular influence. That
is, molecular signals (another form of information) continually serve to influence cell
behavior. Perhaps a slight diversion into adult physiology would permit greater student
insight. The intercommunication of cells and tissues, mainly through hormones and their
relatives, can be explained as another source of information for cells. Students might
then more readily grasp the importance of signaling molecules in embryonic
development. They should now have a basic understanding of the information that
directs cell behavior in the process of embryogenesis. Cells need to proliferate,
differentiate, and organize. Adult tissues often need to perform these same processes,
though students might be challenged to consider some of the significant differences. For
example, fully differentiated cells might make up the bulk of a mature tissue, and they are
unlikely to provide a means of proliferating. Discussions of the cell cycle, another
standard textbook topic, and its regulation can now be brought to bear on embryogenesis
and adult tissue maintenance. Disruptions of this process, including cancer, might also be
presented to stimulate student interest and to increase student awareness of the challenges
facing multicellular animals.
At this point, students can now attempt to formulate the basis of a strategy for
fabricating new tissues for compromised individuals. Again, descriptions of adult tissue
structure, function, and maintenance might be included to more narrowly define a tissue
engineering project. It is hoped that students would recognize the need for a combination
of effective cell populations, proper signals, and perhaps an organizing framework for the
cell population. One strategy for encouraging student comprehension can take the form
of the question: “Embryos succeed at generating tissues, so how could you mimic that
process artificially?” Again, describing both embryonic and adult tissue composition can
provide clues. Undifferentiated cells, stem cells, permit proliferation and ultimate
differentiation. Clearly, a number of issues can be raised at this point in the curriculum.
Where would one obtain undifferentiated cells? Considering the previous topics
addressed relating to embryogenesis and adult tissue maintenance, the concept of stem
cells should become apparent. What signals might be required, and at what
concentration, for influencing cells to proliferate and differentiate according to plan?
Again, previous topics, particularly those involving hormones and gene expression,
provide sufficient clues. A more subtle question involving organization arises. How can
a population of cells produce the correct three-dimensional tissue construct. Clues might
be found in a review of adult tissue composition, revealing the importance of the
extracellular matrix, which might also provide clues to developing a temporary,
biodegradable scaffold for such cell organization. The importance of angiogenesis might
also be addressed as a necessary requirement for successful tissue regeneration.
Other issues alluded to in standard texts can also be reinforced through this
thematic approach. For example, culturing and maintaining cells outside of a body
provides students with puzzles to spark their interest while reinforcing concepts of basic
and applied life science. Certainly, the very application of such principles raises a myriad
of bioethical issues which can addressed throughout this type of curriculum. Stem cell
technology and its utilization within our health care system present one such fascinating
dilemma for student consideration.
In all, it can be clearly demonstrated that many of the basic biology concepts
presented within introductory biology can be taught within a thematic framework of
regenerative medicine. The challenges facing tissue engineers can be used a means to
expose students to some of the most relevant and intriguing questions in life science. In
addition, students can more readily grasp the connections inherent in the realm of biology
through the challenge of restoring normal tissue function by means of a dawning
biomedical revolution. Engaging students with a relevant, exciting puzzle can only make
the science of biology appear to be a more personal and dynamic activity.
Tissue Engineering Course Application
Within the context of a standard high school introductory biology curriculum, the
PTEI outreach education manual in tissue engineering can serve as a platform for the
integration of a number of key biological concepts. Biology instructors typically follow a
direct path through a standard text, covering mandated content chapter by chapter,
supplemented by suggested student activities meant to reinforce content, key concepts,
and science process. This strategy often fails to reinforce critical connections between
topics or concepts because it does not provide a unifying theme or example to accomplish
that elusive goal. As well, students are rarely challenged to identify key questions that
could elucidate underlying connections and to suggest their potential applications in the
real world.
Teachers of introductory biology generally proceed up a perceived chain of
organizational complexity, and this is reinforced by many textbooks. Chapters on basic
chemistry and biochemistry lead to chapters on cell structure, organization, and
physiology. Cell processes such as energy metabolism, transcription, translation, and
reproduction often lead directly to genetics and applied DNA science. Throughout the
sequence of the central dogma (DNA transcription to RNA: RNA translation to protein)
and DNA science, some teachers may include a discussion of gene expression and
perhaps its relationship to the process of multicellular development, but this often is not
related to human physiology and pathology. As well, human anatomy and physiology are
often addressed late in the school year, if at all. For those teachers who do include even a
little human anatomy and physiology, it is often in the context of a comparative survey
among animal taxa. The concepts of human health and biomedical research appear to be
addressed most often as interesting sidelights to, or applications of, the current life
science topic of study. Examples of this strategy include abnormal gene function and its
relationship to inherited disease, microbial influence on human disease, and abnormal
cellular responses (or growth characteristics) leading to cancer. Tissue engineering
provides a forum that could enable teachers to readily reveal the connections between
many of these same basic content areas, with the added attraction of addressing human
biomedical concerns.
A curriculum employing tissue engineering (TE) as a unifying theme can address
much of the content covered in introductory life science by challenging students to
identify key questions and knowledge that might be required to aid people with
compromised tissue function. One such approach might begin with a familiar
organizational theme. What is the composition of a human body? Basic chemical
concepts, along with biochemistry, would serve to begin the search for a means to
regenerate tissue. Higher-order organization of these components leads logically to a
discussion of cellular anatomy and physiology. An understanding of cell structure and
physiologic processes can be identified as key components of the tissue regeneration
puzzle. Teachers and students would then be motivated to understand the organization
and functionality of populations of cells: How do cells organize? What types of body
structures result, and how are their functions regulated? More subtle questions would
involve the continuity of both structure and function; for example, do cell populations or
subpopulations change in form and/or function in a given tissue? Are cells reproducing
and/or dying? How are these changes in cell populations regulated? From a more basic
standpoint, how did these tissues and inherent dynamic processes come about? These
questions address some of the key and best-researched questions in life science and offer
a dramatic segue into the realm of cell information processing.
The questions posed in the preceding paragraph, as well those questions
pertaining to multicellular development, cell replication, cell-cell (or tissue-tissue)
interaction, and even certain disease states, can be intimately related to the phenomena of
intracellular and extracellular information processing. At its root, the processes of DNA
replication, transcription, and translation determine cell structure, multicellular
development and organization, and tissue regulation. Thus, teachers can guide students
to this realization by posing these defining questions, or have students independently
generate such a list. For example, consider the fundamental question: How does the
multicellular human condition arise? Clearly, students should eventually come to
propose that it is not by chance. That is, cells are adhering to instructions or some form
of information. Explaining the nature of the information (DNA sequences and molecules
produced as a consequence of their ‘reading’) within this context provides a human focus
to the central dogma. However, students might be able to recognize more subtle
questions related to this standard explanation. Do all the cells of a particular human (or
developing embryonic human) possess the same DNA? What key experiments shed light
on this important question? If all cells of an embryo possess equivalent DNA, how do
cells assume different structures and functions? What influences differentiation? How is
the information passed from one generation to the next? Can information controlling
tissue development and organization be adversely affected, and what might be the
consequences of such disruption? Clearly, standard textbook material relating to the
central dogma can serve as the basis for the answers to many of these questions.
However, challenging students to define these key questions and to propose adequate
answers should allow them to make connections not often stressed in typical classrooms.
Once students come to realize that the DNA of embryonic cells is virtually
equivalent, teachers can then lead them to the phenomena of extracellular influence. That
is, molecular signals (another form of information) continually serve to influence cell
behavior. Perhaps a slight diversion into adult physiology would permit greater student
insight. The intercommunication of cells and tissues, mainly through hormones and their
relatives, can be explained as another source of information for cells. Students might
then more readily grasp the importance of signaling molecules in embryonic
development. They should now have a basic understanding of the information that
directs cell behavior in the process of embryogenesis. Cells need to proliferate,
differentiate, and organize. Adult tissues often need to perform these same processes,
though students might be challenged to consider some of the significant differences. For
example, fully differentiated cells might make up the bulk of a mature tissue, and they are
unlikely to provide a means of proliferating. Discussions of the cell cycle, another
standard textbook topic, and its regulation can now be brought to bear on embryogenesis
and adult tissue maintenance. Disruptions of this process, including cancer, might also be
presented to stimulate student interest and to increase student awareness of the challenges
facing multicellular animals.
At this point, students can now attempt to formulate the basis of a strategy for
fabricating new tissues for compromised individuals. Again, descriptions of adult tissue
structure, function, and maintenance might be included to more narrowly define a tissue
engineering project. It is hoped that students would recognize the need for a combination
of effective cell populations, proper signals, and perhaps an organizing framework for the
cell population. One strategy for encouraging student comprehension can take the form
of the question: “Embryos succeed at generating tissues, so how could you mimic that
process artificially?” Again, describing both embryonic and adult tissue composition can
provide clues. Undifferentiated cells, stem cells, permit proliferation and ultimate
differentiation. Clearly, a number of issues can be raised at this point in the curriculum.
Where would one obtain undifferentiated cells? Considering the previous topics
addressed relating to embryogenesis and adult tissue maintenance, the concept of stem
cells should become apparent. What signals might be required, and at what
concentration, for influencing cells to proliferate and differentiate according to plan?
Again, previous topics, particularly those involving hormones and gene expression,
provide sufficient clues. A more subtle question involving organization arises. How can
a population of cells produce the correct three-dimensional tissue construct. Clues might
be found in a review of adult tissue composition, revealing the importance of the
extracellular matrix, which might also provide clues to developing a temporary,
biodegradable scaffold for such cell organization. The importance of angiogenesis might
also be addressed as a necessary requirement for successful tissue regeneration.
Other issues alluded to in standard texts can also be reinforced through this
thematic approach. For example, culturing and maintaining cells outside of a body
provides students with puzzles to spark their interest while reinforcing concepts of basic
and applied life science. Certainly, the very application of such principles raises a myriad
of bioethical issues which can addressed throughout this type of curriculum. Stem cell
technology and its utilization within our health care system present one such fascinating
dilemma for student consideration.
In all, it can be clearly demonstrated that many of the basic biology concepts
presented within introductory biology can be taught within a thematic framework of
regenerative medicine. The challenges facing tissue engineers can be used a means to
expose students to some of the most relevant and intriguing questions in life science. In
addition, students can more readily grasp the connections inherent in the realm of biology
through the challenge of restoring normal tissue function by means of a dawning
biomedical revolution. Engaging students with a relevant, exciting puzzle can only make
the science of biology appear to be a more personal and dynamic activity.