Biocompatibility: Exam 2 Handouts!

Front 1

In response to implanted biomaterials, what has the highest intensity first?

Back 1

PMNs or Neutrophils!

Front 2

In response to implanted biomaterials, what has the next highest intensity first?

Back 2

Mononuclear leukocytes (monocytes!)

Front 3

In response to implanted biomaterials, in order of intensity and time duration, what 4 things come into play?

Back 3

1. Macrophages
2. Neovascularization
3. Foreign body giant cells
4. Fibroblasts

Front 4

In response to implanted biomaterials, what is the last thing to come into play well into the granulation tissue?

Back 4

Fibrosis!

Front 5

What 5 cell types have high cellular turnover and high regenerative potential?

Back 5

1. Blood cells
2. Mammary epithelium
3. Gut epithelium
4. Epidermis
5. Vascular endothelium

Front 6

What 5 cell types have low cellular turnover but high regenerative potential?

Back 6

1. Liver
2. Small vasculature
3. Skeletal muscle
4. Pancreas
5. Adrenal cortex

Front 7

What 6 cell types have low cellular turnover and low regenerative potential?

Back 7

1. Lung parenchyma
2. Brain
3. Kidney
4. Heart
5. Spinal cord

Front 8

What are the 9 basic cell functions of contact dependent cells?

Back 8

1. Adhesion
2. Morphology
3. Survival and apoptosis
4. Motility/haptotaxis
5. Proliferation
6. Differentiation
7. Synthesis of macromolecules
8. Formation of ECM
9. Cell-to-Cell signalling

Front 9

What are the 5 cell functions pertinent to new tissue formation?

Back 9

1. Cell adhesion
2. Cell migration
3. Cell replication/proliferation
4. Cell apoptosis
5. Cell differentiation

Front 10

If present, what can basically stop the wound healing process?

Back 10

Infection!

Front 11

In infection, what two things affect the healing of skin injuries?

Back 11

1. Presence of infection
2. Duration of infection

Front 12

What are Stem Cells?

Back 12

Cells that have not yet differentiated terminally and have the potential to rise to various other types of cells.

Front 13

What are the 3 important characteristics that distinguish stem cells from other cells?

Back 13

1. Ability to self-renew for a long time
2. Non-specific
3. Can be induced to differentiate into organ-specific cells under right conditions

Front 14

What is the differentiation potential of Totipotent stem cells?

Back 14

Into an entire organism!

Front 15

What is the differentiation potential of Pluripotent stem cells? Examples?

Back 15

First three germ layers. Examples: Cells of inner call mass of blastocyte, EMBRYONIC stem cells

Front 16

What is the differentiation potential of Multipotent stem cells? Example?

Back 16

Multiple stem cells. Example: Mesenchymal stem cells (can become bone, cartilage or fat cells)

Front 17

What is the differentiation potential of Oligopotent stem cells? Example?

Back 17

Two or more lineages. Example: neural stem cells

Front 18

What is the differentiation potential of unipotent stem cells? Example?

Back 18

Single lineage like spermatogonial stem cells

Front 19

What are the 5 stages of Stem Cell Potency?

Back 19

1. Toti
2. Pluri
3. Multi
4. Oligo
5. Uni

Front 20

Are the two main properties of a Stem Cell?

Back 20

1. Self-renewal
2. Differentiation

Front 21

What is Self-Renewal?

Back 21

The ability of a stem cell to make identical copies of itself

Front 22

What is Differentiation?

Back 22

The ability of a stem cell to form other cell types of various tissues

Front 23

What are the 5 steps in the Stem Cell Cycle leading to Differentiation?

Back 23

1. Stem cell
2. Progenitor/Precursor/Transit Amplifying Cell
3. Committed Cell
4. Terminally-Differentiated Cell
5. Mature Cell

Front 24

What is a Niche?

Back 24

A microenvironment that provides a sheltering environment for stem cells in which the balance between state of being and activity/function is maintained.

Front 25

What is the purpose of a Niche?

Back 25

To maintain the stem cells stemness

Front 26

What ensures the maintenance of the stem cell phenotype?

Back 26

Balanced interaction between stem cells, niche cells, ECM and the secreted chemical compounds/GFs.

Front 27

Why may stem cells out of the body not behave as they do in the body?

Back 27

Because they have been isolated, purified, and cultured devoid of their niche!

Front 28

Which were the first to be isolated: mouse or human embryonic stem cells?

Back 28

Mouse! in 1981

Front 29

TRUE OR FALSE: Embryonic stem cells exist in the body after birth.

Back 29

FALSE

Front 30

How are embryonic stem cells obtained?

Back 30

Isolated from the inner cell mass of the blastocyst and are expanded in vitro

Front 31

What are embryonic stem cells?

Back 31

Pluripotent cells derived from embryos

Front 32

What are two advantages of Mouse Embryonic Stem Cells?

Back 32

1. A model system that has provided important information including isolation, development, growth and differentiation
2. May provide further knowledge

Front 33

What is a limitation of Mouse embryonic stem cells?

Back 33

You cannot use them in clinical applications.

Front 34

Human embryonic stem cells used in scientific studies are derived from what?

Back 34

Embryos created (but not used) for reproductive purposes using in vitro fertilization methods

Front 35

How can we take the few adult stem cells found in the blood and increase their number but maintain their stemness?

Back 35

Possibly by implementing the correct GFs and biophysical forces

Front 36

US passed a law saying that embryonic stem cells could not be research if what was true?

Back 36

If the research was funded by the federal government.

Front 37

What is the number of adult stem cells in the body?

Back 37

1 in 100,000 in the bone marrow

Front 38

What are Adult Stem Cells?

Back 38

Undifferentiated cells found among differentiated and specialized cells of tissues and organs in the body.

Front 39

Adult stem cells are known as what?

Back 39

Somatic stem cells

Front 40

What is the potency of Adult Stem Cells?

Back 40

They are multipotent in that they can differentiate into various cell types but are restricted to specific lineages.

Front 41

Hematopoietic stem cells are present where?

Back 41

Bone marrow, placenta and the umbilical cord

Front 42

Mesenchymal stem cells are present where?

Back 42

Bone marrow of iliac crest and of the femoral heads and fat tissue

Front 43

The potency of a stem cell population to differentiate into cells of various tissues can be determined where? In vitro or only in vivo?

Back 43

In vitro! but the ultimate proof of such outcomes is the formation of functional tissue in vivo

Front 44

How do you characterize haemotopoietic stem cells?

Back 44

In vivo assay: long-term repopulation assay

Front 45

How do you characterize mesenchymal stem cells?

Back 45

In vitro formation of fat, cartilage, and bone
In vivo experiments using immuno-deficient animals

Front 46

In order to optimize the cell culture protocol, what 3 things must be resolved?

Back 46

1. Requirement of serum from animals and sialic Neu5Gc issues
2. Possible immune-rejection by the host
3. Difficulties in obtaining a homogeneous cell type from heterogeneous population

Front 47

What are the 3 requirements for human stem cell applications?

Back 47

1. Optimization of the culture method
2. Optimization of the cell culture protocol
3. Demonstration that it will work in large animal models

Front 48

What is the major challenge in Vitro Differentiation?

Back 48

Differentiation of pluripotent and multipotent stem cells into a homogenous population of differentiated cells

Front 49

What are possible solutions for the major challenge?

Back 49

1. Cell culture medium changes (biochemical stimuli) like GF, Cytokines, other proteins
2. Cell Culture Environment changes like 2 and 3D, cocultures, and biophysical stimuli

Front 50

What are 3 future directions of Stem Cells?

Back 50

1. Understanding underlying mechanisms and differentiation
2. Tissue engineering, regenerative med, + novel theraputics
3. Translation of stem cell methodologies from the lab into the clinic (From bench to bed.)

Front 51

What is another Major Challenge of stem cells in terms of undifferentiated cells?

Back 51

Increase the number of undifferentiated stem cells in vitro (cell expansion)

Front 52

What are the possible solutions to the expansion of undifferentiated cells?

Back 52

1. Develop novel cell culture conditions
2. Bioreactors

Front 53

What are the 3 host tissue responses?

Back 53

1. Acute response
2. Adaption
3. Abnormal outcome

Front 54

What is Adaptation?

Back 54

The ability of tissues to remodel "adaptively" to reflect changes in demand and function.

Front 55

What is Resolution?

Back 55

Achievement of a final state after which no more progressive biological changes occur (steady state situation!)

Front 56

What are the four possible outcomes of healing around Implants?

Back 56

1. Extrusion
2. Resorption
3. Integration
4. Encapsulation

Front 57

What is Resorption?

Back 57

When resorbable materials are used, the implant site may resolve to a collapsed scar or completely disappear (ideal).

Front 58

What is Integration?

Back 58

Nearly normal host tissue is formed around the implant without an intervening fibrotic capsule.

Front 59

What is the process of forming a pocket or pouch forming around the implant called?

Back 59

Marsupialiation!

Front 60

What are the 4 Local Factors which affect the wound healing process and outcome around implanted materials and devices?

Back 60

1. Site (tissue or organ) of implantation
2. Adequacy of blood supply
3. Age
4. Infection

Front 61

What are the 7 Systemic Factors which affect the wound healing process and outcome around implanted materials and devices?

Back 61

1. Genetic
2. Pre-existing diseases
3. Nutrition
4. Medications taken
5. Chronic diseases
6. Infection
7. Other conditions (stress, smoking, obesity, etc)

Front 62

What are the 5 inflammatory cell infiltration in Biomaterials?

Back 62

1. Monocyte adhesion
2. Macrophage differentiation
3. Macrophage mannose
4. Receptor Upregulation
5. Macrophage fusion

Front 63

What does the inflammatory cell infiltration in the Biomaterial side lead to?

Back 63

Foreign Body Giant Cell Formation!

Front 64

After implantation, on the exudate/tissue side, what are the 4 steps?

Back 64

1. Acute inflammation
2. Chronic inflammation
3. Granulation tissue
4. Fibrous capsule formation

Front 65

What is Frustrated Macrophagocytosis?

Back 65

Macrophages can't digest implant and thus become "frustrated" where they release toxic contents into the tissue which irritates surrounding cells.

Front 66

What was the amendment that said there could be ZERO levels of carcinogenic agents in food additives or medical implants?

Back 66

Delaney Amendment

Front 67

Which 3 things in the body do not usually give observable signs and symptoms until damage is extreme?

Back 67

1. Brain
2. Skeletal system
3. Muscles

Front 68

What is Metallosis?

Back 68

medical condition involving deposition and build-up of metal debris in the soft tissues of the body

Front 69

TRUE OR FALSE: Metal ions can enter cells and alter their function.

Back 69

TRUE

Front 70

What is the total body water?

Back 70

~42 Liters or 60% of body weight

Front 71

Which compartment in the body holds the most water? Followed by what two compartments?

Back 71

Intracellular followed by extracellular and then plasma

Front 72

Which Tissue in the body holds the most water? Followed by what?

Back 72

Muscle followed by skin, blood, and others