National Academies Press: OpenBook
« Previous: References
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

Glossary


Adult stem cell

- An undifferentiated cell that is found in differentiated adult tissue, can renew itself, and can (with certain limitations) differentiate to yield all the specialized cell types of the tissue from which it originated.

Antigen

- Any substance, usually a protein, that stimulates an immune response.

Autologous transplant

- Transplanted tissue that is derived from the intended recipient of the transplant. Such a transplant helps avoid complications of immune rejection.


Blastocyst

- A preimplantation embryo of 30-150 cells and 4-7 days of age. The blastocyst consists of a sphere made up of an outer layer of cells (the trophectoderm), a fluid-filled cavity (the blastocoel), and a cluster of cells on the interior (the inner cell mass).

Bone marrow

- The soft, living tissue that fills most bone cavities and contains hematopoietic stem cells from which all red and white blood cells evolve. The bone marrow also contains mesenchymal (stroma) stem cells that a number of cells types come from, including chondrocytes, which produce cartilage.

Bone marrow cell

- Refers to both hematopoietic cells and mesenchymal (stromal) cells.

Bone marrow stem cell

- Refering to one of at least two types

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

of multipotent stem cells: hematopoietic stem cell and mesenchymal stem cell.


Chromosomes

- Nucleic acid-protein structures in the nucleus of a cell. Chromosomes are composed chiefly of DNA, the carrier of hereditary information. Chromosomes contain genes, working subunits of DNA that carry the genetic code for specific proteins, interspersed with large amounts of DNA of unknown function. A normal human body cell contains 46 chromosomes; a normal human gamete (egg or sperm), 23 chromosomes.

Cytoplasm

- The contents of a cell, other than the nucleus cytoplasm, consists of a fluid containing numerous structures, known as organelles, that carry out essential cell functions.


Dendrite

- Extension of a nerve cell, typically branched and relatively short, that receives stimuli from other nerve cells.

Differentiation

- The process whereby an unspecialized early embryonic cell acquires the features of a specialized cell such as a heart, liver, or muscle cell.

DNA

- A chemical, deoxyribonucleic acid, found primarily in the nucleus of cells. DNA carries the instructions for making all the structures and materials the body needs to function.


Ectoderm

- The upper, outermost of the three primitive germ layers of the embryo that will give rise to the skin, hair, nails, nerve, and brain including the retina of the eye.

Embryo

- In humans, the developing organism from the time of fertilization until the end of the eighth week of gestation, when it becomes known as a fetus.

Embryonic germ cell

- Cells found in a specific part of the embryo/fetus called the gonadal ridge, and normally develop into mature gametes.

Embryonic stem cell (ESC)

- Primitive (undifferentiated) cell from the

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

embryo that have the potential to become a wide variety of specialized cell types.

Endoderm

- The lower, inner of the three primitive germ layers of the embryo that will give rise to the epithelial layers of the lungs and bronchi, pharynx, gastrointestinal tract, liver, pancreas, and urinary bladder.


Fertilization

- The process whereby male and female gametes unite.


Gene

- A functional unit of heredity that is a segment of DNA and located in a specific site on a chromosome. Genes generally direct the formation of an enzyme or other protein.

Genome

- The complete genetic material of an organism.

Germ cell

- A gamete, that is, a sperm or egg, or a cell that can become a sperm or egg. All other body cells are somatic cells.

Germ layers

- The three initial tissue layers arising in the embryo— endoderm, mesoderm, and ectoderm—from which all other somatic tissue-types develop.

Gonadal ridge

-Anatomic site in the early fetus where primordial germ cells are formed.

Graft-versus-host disease

- A condition that occurs following bone marrow transplant in which the donor’s immune cells, in the transplanted marrow, make antibodies against the host’s tissues.


Hematopoietic stem cell (HSC)

- A stem cell from which all red and white blood cells evolve.

Hepatic

- Relating to the liver.

Histocompatible

- The immunological characteristic of cells or tissue that causes them to be tolerated by another cell or tissue; that allows some tissues to be grafted effectively to others.


Immune system cells

- White blood cells or leukocytes that originate from the bone marrow. They include antigen-presenting cells, such as

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

dendritic cells, T and B lymphocytes, and neutrophils, among many others.

In vitro

- From the Latin for, “in glass”; in a laboratory dish or test tube; an artificial environment.

In vitro fertilization (IVF)

- An assisted reproduction technique in which fertilization is accomplished outside the body.

In vivo

- In the living subject; a natural environment.

Inner cell mass

- The cluster of cells inside the blastocyst. These cells give rise to the embryonic disk of the later embryo and ultimately the fetus. They are the source of embryonic stem cells.


Lipid

- Any one of a group of fats or fat-like substances characterized by their insolubility in water and solubility in fat solvents such as alcohol, ether, and chloroform.

Lymphocyte

- A type of white blood cell that is part of the body’s cellular immune system; present in the blood and lymphatic tissue.


Macrophage

- A lymphocyte that has left the circulation and settled and matured in a tissue. Because of their placement in the lymphoid tissues, macrophages serve as the major scavenger of the blood, clearing it of abnormal or old cells and cellular debris as well as pathogenic organisms.

Mesenchyme

- Connective tissue arising from multiple germ layers consisting of unspecialized cells. A number of cell types come from the mesenchyme, including the cells that give rise to collagen, muscle, cartilage, and bone.

Mesoderm

- The middle of the three primitive germ layers of the embryo. These cells occur between the ectoderm and endoderm and give rise to most of the cardiovascular system, blood cells and bone marrow, the skeleton, smooth and striated muscles, and parts of the reproductive and excretory system.

Morula

- A solid mass of 12 or more cells that resembles a mulberry,

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

occurring at 3 to 4 days after fertilization and that results from the cleavage of the zygote.

Multipotent

- Capable of differentiating into multiple cell types associated with different organs.


Neoplastic

- Having the characteristic of potentially malignant growth.

Neural stem cell

- A stem cell that can give rise to the different types of cells of the nervous system. Neural stem cells are found in certain areas of the adult brain, in embryos, fetuses, newborns, and juveniles.

Neuron

- The key data-processing cell of the nervous system. Each neuron has a cell body and one or more processes (extensions) called dendrites and axons. Neurons function by the initiation and conduction of electrical impulses that are transmitted to other neurons or cells.


Ovum

- An egg, the female germ, or sex, cell produced in the ovaries.


Placenta

- The oval or discoid spongy structure in the uterus from which the fetus derives its nourishment and oxygen

Plasticity

- The ability of a cell to differentiate into a cell type beyond the tissue in which it normally resides.


Somatic cell

- Any cell of a plant or animal other than a germ cell or germ-cell precursor.

Somatic cell nuclear transfer

- The transfer of a cell nucleus from a somatic cell into an egg from which the nucleus has been removed.

Stem cell

- A cell that has the ability to divide for indefinite periods in culture and to give rise to specialized cells.

Stromal cell

- A non-blood cell that is derived from blood organs, such as bone marrow or fetal liver, which is capable of supporting growth of blood cells in vitro. Stromal cells that make up the matrix within the bone marrow are derived from the mesenchyme and give rise to fat and cartilage.

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×

Surface antigen

- Proteins on the surface of cells that are capable of detection by antibodies or other means. These may stimulate an immune response.


T cell

- A type of white blood cell that is of crucial importance to the immune system. Immature T cells (termed T-stem cells) migrate to the thymus gland in the neck, where they differentiate into various types of mature T cells and become active in the immune system. T cells that are potentially activated against the body’s own tissues are normally killed or changed (“down-regulated”) during this maturation process.

Tissue culture

- Growth of tissue in vitro on an artificial media for experimental research.


Undifferentiated

- Not having changed to become a specialized cell type.


White blood cell

- Also known as a leukocyte. These cells normally protect against infection by, for example, ingesting bacteria or secreting antibodies. White blood cells are formed from the undifferentiated stem cell that can give rise to all blood cells. Those in the bone marrow may become any of the five types of white blood cells. Those in the spleen and lymph nodes may become lymphocytes, or monocytes, and those in the thymus can become lymphocytes (T-lymphocytes).


Zygote

- The cell formed by the union of male and female germ cells (sperm and egg, respectively).

Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 67
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 68
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 69
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 70
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 71
Suggested Citation:"Glossary." National Research Council and Institute of Medicine. 2002. Stem Cells and the Future of Regenerative Medicine. Washington, DC: The National Academies Press. doi: 10.17226/10195.
×
Page 72
Next: Appendix A: Committee Biographies »
Stem Cells and the Future of Regenerative Medicine Get This Book
×
Buy Paperback | $40.00 Buy Ebook | $31.99
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

Recent scientific breakthroughs, celebrity patient advocates, and conflicting religious beliefs have come together to bring the state of stem cell research—specifically embryonic stem cell research—into the political crosshairs. President Bush’s watershed policy statement allows federal funding for embryonic stem cell research but only on a limited number of stem cell lines. Millions of Americans could be affected by the continuing political debate among policymakers and the public.

Stem Cells and the Future of Regenerative Medicine provides a deeper exploration of the biological, ethical, and funding questions prompted by the therapeutic potential of undifferentiated human cells. In terms accessible to lay readers, the book summarizes what we know about adult and embryonic stem cells and discusses how to go about the transition from mouse studies to research that has therapeutic implications for people.

Perhaps most important, Stem Cells and the Future of Regenerative Medicine also provides an overview of the moral and ethical problems that arise from the use of embryonic stem cells. This timely book compares the impact of public and private research funding and discusses approaches to appropriate research oversight.

Based on the insights of leading scientists, ethicists, and other authorities, the book offers authoritative recommendations regarding the use of existing stem cell lines versus new lines in research, the important role of the federal government in this field of research, and other fundamental issues.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text.

    « Back Next »
  6. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  7. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  8. ×

    View our suggested citation for this chapter.

    « Back Next »
  9. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!