This compilation of abbreviations and terms is provided to help interpret the topic material. This is also a valuable resource when investigating the primary literature cited in the FAQ's and Recommended Articles.
Abbreviation/Term |
Meaning/Definition |
| Aa |
Amino Acid |
| Ab |
Antibody |
| Adhesion Molecules |
Membrane-expressing molecules that mediate interactions of stem cells and progenitors with stromal cells or with extracellular matrix proteins in the bone marrow microenvironment. |
| Adipose cells |
Fat cells in the bone marrow |
| Ag |
Antigen |
| AGM |
Aorta-gonads-mesonephros: Site LHSC in the embryo. |
| Angiogenesis |
The growth and sprouting of additional blood vessels from pre-existing blood vessels |
| AML |
Adult Myeloid Leukemia |
| APC |
Antigen Presenting Cell |
| AsymetricDivision |
One daughter cell quiescent and the other proliferating and moving away from site of division |
| Autophagy |
Self-eating cells: Delivery of cytoplasmic constituents such as whole organeels to the lysosome for degradation. Occurs during starvation, aging and development. It is a recycling process. |
| BFU-E |
Erythrocyte Burst Forming Unit (Early erythroid progenitors) |
| Blastocyte (or blastula) |
4-5 day embryo formed prior to implantation in the uterus. Is comprised of a hollow mass of only a few undifferentiated stem cells. |
| BM |
Bone Marrow |
| Bp |
Base pair |
| BSA |
Bovine Serum Albumin |
| CD |
Cluster Designation: Used with a number to indicate a cell surface marker. |
| CD33 |
Present on committed progenitors in the myeloid lineages. |
| CD34 |
Present on Lymphohematopoietic stem cells and their progenitors. Express at high densities in the most primitive cells and become dim as the cells mature towards differentiation. |
| CD38 |
Not detectable on Lymphohematopoietic stem cells but begin to appear as the cells commit towards a lineage. |
| CD133 |
Also referred as Prominin. A marker of LHSC |
| Cell Release |
Movement of bone marrow cells out of the sinus into the peripheral circulation. |
| CFU |
Colony Forming Unit |
| CFU-E |
Erythrocyte Colony Forming Unit (Late stage erythrocyte progenitors) |
| CFU-GM |
Granulocyte-Macrophage Colony Forming Unit |
| CFU-S |
Colony Forming Unit- Spleen |
| Chemoattractant |
A factor that attract a cell, e.g., a cytokine or a chemokine |
| Chemotaxis |
Attraction of a cell to an area where there is a gradient increase of a particular factor |
| CLP |
Common Lymphoid Progenitor |
| CMP |
Common Myeloid Progenitor |
| CNS |
Central Nervous System |
| cRNA |
Complementary RNA |
| CSF |
Colony stimulating factors: Generally referred to groups of cytokines and other growth factors that can stimulate Lymphohematopoietic stem cells and bone marrow progenitors. (In general, they are the hematopoietic stimulators) |
| CXCR, CXC |
Chemokine receptor |
| Cytokines |
A family of small labile molecules that seem functionally redundant. They are mostly naturally glycoprotein and are important in regulating the maturation of bone marrow stem cells. |
| Da |
Dalton (kDa: kilodalton) |
| Differentiation |
Downward steps towards the development of mature immune and blood cells |
| De-differentiation |
Backward movement of differentiated cells to immature types. |
| DC |
Dendritic Cells |
| Definitive LHSC |
Functional migrating cells that can home to the bone marrow and repopulate the host. |
| Pre-definitive LHSC |
| DNA |
Deoxyribonucleic acid |
| dsDNA |
Double-stranded DNA |
| Diapedesis |
Transendothelial migration |
| EC |
Endothelial Cells |
| EGC |
Embryonic Germ Cells |
| EPC |
Endothelial Progenitor Cells or Adult Angioblasts |
| Epigenetic |
Alterations in gene-expression patterns, without changes in DNA sequence. This could occur by modification of proteins that surround the genomic DNA:
- Cytosine DNA methytlation (a methyl group is transferred from S-adenosylmethionine to C-5 position of cytosine by a family of cytokine-methyltransferases. This generally occurs at CpG nucleotides and is important in the regulation of gene expression and silencing
- Genomic Imprinting: Silencing of a parental gene.
- Histone Modifications: Acetylation, methylation and phosphorylation.
|
| Epigenetic Inheritance |
Transmission of non-DNA sequence via meiosis or mitosis. |
| Euchromatin |
DNA open and available |
| Heterochromatin |
DNA not available |
| Epo |
Erythropoietin (a hormone that stimulate erythropoiesis) |
| Erythropoiesis |
Development of red blood cells |
| ETP |
Early T-lineage Progenitor |
| ELP |
Earliest Rag+ lymphocyte progenitor |
| Extravasation |
Movement of a cell in or out of the bone marrow through endothelial barrier. Chemotaxis cannot account for this type of movement. |
| Extravascular Compartment |
Areas in the bone marrow microenvironment that are not blood vessels |
| ECM |
Extracellular matrix: Fibronectin, collagen etc. Excreted from stromal cells and regulate functions in bone marrow, in particular, LymphoHematopoietic Stem Cells |
| EPC |
Endothelial Progenitor Cell |
| ES |
Embryonic Stem Cell |
| Extramedullary |
Outside the bone marrow |
| FACS |
Fluorescence-activated cell sorter |
| FITC |
Fluorescein isothiocyanate (Use to tag other proteins (e.g., antibodies) for immunofluorescence) |
| FL |
Fetal Liver |
| FCS |
Fetal Calf Sera |
| FSC |
Forward Scatter |
| G-CSF |
Granulocyte colony stimulating factor: Used to mobilize bone marrow in the periphery and to differentiate granulocyte precursor to neutrophils. |
| GM-CSF |
A cytokine: Granulocyte-Macrophage colony stimulating factor: Growth factors for Lymphohematopoietic stem cells. |
| GMP |
Granulocyte/macrophage progenitor |
| Genomic Imprinting |
The expression of a gene depending on which parental allele is expressed. |
| Harvesting |
Collecting bone marrow cells for transplantation |
| Hematopoiesis |
Formation of 8 distinct lineages from a Lymphohematopoietic Stem Cell (LHSC) |
| Hgb |
Hemoglobin |
| HLA-DR |
Hluman Histocompatibility Leukocyte Antigen-DR (analogous to MHC-Class II) |
| HME |
Hematopoietic/Bone Marrow Microenvironment |
| Homing |
A cell when transplanted, goes to a particular site through specific, e.g., if a Lymphohematopoietic stem cells given intravenously goes directly to the bone marrow and forms its niche in the area of stromal cells. |
| HUVEC |
Human Umbilical Vein Endothelial Cells |
| IFN |
Interferon |
| Interleukins |
A growing family of cytokines. To date there are 22 members in the family. |
| Intramedullary |
Inside the bone marrow |
| Intravascular Compartment |
Blood vessels within the bone marrow microenvironment |
| LHSC (sometimes referred as HSC) |
LymphoHematopoietic Stem Cell |
| Lin (-) |
When several antibodies are used to deplete committed progenitors. The remaining cells are lineage negative (Lin -). |
| Lymphohematopoietic (LHSC): General |
Bone Marrow System that generates immune and blood cells. |
| LHSC (human) |
In general: CD34+/Lin - |
| LHSC (mouse) |
Sca1+/s-kit+/Lin- |
| LN |
Lymph node |
| LTC-IC |
Long term culture initiating cells assay (To study primitive bone marrow progenitors) |
| LT-HSC |
Long-term hematopoietic stem cell |
| Lymphopoiesis |
Development of lymphoid cells: T-cell, B-cells, NK cells and Dendritic cells, DC (only if NK and DC cells are formed from the lymphoid lineages) |
| Mature |
Usually referred to the differentiated cells of hematopoietic lineages. |
| M-CSF |
Monocyte-Colony Stimulating Factor |
| Megakaryocyte |
Cells of myeloid lineage that differentiate into platelets |
| MEP |
Megakaryocyte/erythrocyte progenitor |
| MHC-Class I |
Major Histocompatibility Complex, Class I: Expressed on all cells. |
| MHC-Class II |
Major Histocompatibility Complex, Class II: Expressed on bone marrow Lymphohematopoietic stem cells, antigen presenting cells, mesenchymal stem cells, activated T-cells |
| Microenvironment |
The structures, cells, factors (e.g., ECM), nerve fibers etc that comprise the bone marrow/hematopoietic system. |
| Migration |
Cells that move from one site to the other, in the absence of a known chemoattractant. |
| MK |
Megakaryocyte |
| MLR |
Mixed Lymphocyte Reaction |
| MΦ |
Macrophage |
| MNC |
Mononuclear Cells |
| Mobilization |
Injecting a chemoattractant to move stem cells from the bone marrow into the periphery. |
| Monopotent |
A bone marrow progenitor that has matured but is committed towards one lineage. |
| Morula |
Spheroidal mass of cells from early cleavage divisions of the zygote. |
| MPC or MAPC |
Multiple progenitor or multiple adult progenitor: These are terminologies used by Dr. C. Verfaillie (Univ. of Minnisota) to describe her stem cell that others referred as mesenchymal stem cell. |
| MPP |
Multipotent Progenitor |
| mRNA |
Messenger RNA |
| MSC |
Mesenchymal Stem Cell |
| Multipotent |
A multipotent cell is not a stem cell but is close to a stem cell with regards to cell maturation. Thus, a multipotent cell has less potential to survive for a long period as compared to a pluripotent stem cell. These types of cells are considered as `cell in transition’. |
| Myelopoiesis |
Lineages distinct from the lymphoid lineages. |
| NCS |
Neural Stem Cell |
| Niche |
Stabilization of a cell in a particular microenvironment and area of the bone marrow. |
| NK |
Natural Killer cells |
4-Oct |
Octamer Binding Factor: Important in ES and prevents differentiation. |
| Ontogeny |
Development of Lymphohematopoietic System |
| Parthenogenesis |
Embryonic development without male contribution. |
| PBMC |
Peripheral Blood Mononuclear Cells |
| Pericyte |
This is an old terminology. Currently, these cells might be the recently defined mesenchymal stem cells. |
| Pluripotent Cell |
A self-renewing cell that has the capability to commit toward different cell lineages along one germ layer, e.g., hematopoietic stem cells can make immune and red blood cells. Thus, a pluripotent cell is a stem cell. |
| PMN |
Polymorphonuclear Cells (e.g., neutrophils) |
| Precursor |
The stage of lineage just before the differentiated cell. |
| Primitive LHSC |
Cells cannot home to the bone marrow and repopulate a host. Needs to undergo maturation on stromal cells and cytokines. |
| Reticular Cell |
Non-descript cells in the bone marrow that have not been characterized. Sometimes fibroblasts and mesenchymal stem cells are referred as reticular cells. |
| RNA |
Ribonucleic Acid |
| SCID |
Severe Combined Immundeficiency |
| SSEA |
Stage-specific embryonic antigen |
| SH-2, -3, -4 |
Markers developed by Osiris Biotechnology to detect mesenchymal stem cells. SH-2 has the specificity as for CD105 (endoglin) and SH-4 for stro-1 |
| Sinus |
Marrow sinus: Area of the blood vessels where the arterial and venous blood mix. Mature hematopoietic cells and other bone marrow cells exist through the sinus into the peripheral circulation. |
| Spln |
Spleen |
| SRC |
SCID repopulating cells |
| SSC |
Side Scatter |
| Stochastic |
Ramdom |
| Stroma |
The supporting layer of hematopoiesis in bone marrow |
| ST-HSC |
Short-term hematopoietic stem cell |
| TdT |
Terminal deoxynucleotidyltransferase |
| TERT |
Telomerase reverse transcriptase (hTERT = human…) |
| TF |
Transcription Factor |
| Tg |
Transgenic |
| TGF- |
Transforming Growth Factor |
| TNF- |
Tumor Necrosis Factor- |
| Totipotent |
Unlimited potential to differentiate into cells of the three germ layers, e.g., Embryonic Stem Cells. These cells can also generate trophoblasts. |
| TPO |
Thrombopoietin |
| Trabeculae |
Soft bones in the marrow compartment |
| Transdifferentiation 1 |
Cells in one lineage forming cells of another lineage, e.g., lymphoid cells forming myeloid type cells. |
| Transdifferentiation 2 |
Stem cells in one organ forming differentiated cells of another organ, e.g., bone marrow stem cells forming hepatocytes. |
| Traffic |
Trafficking or circulation of cells refer to the movement of cells out of the bone marrow and through the periphery. The cells might return to the bone marrow. |
| Translocation |
Breaking part of a chromosome to another chromosome, e;g., bcr - abl oncogene formed by translocation, t(9:22) as seen in chronic myeloid leukemia (CML). |
| UCB |
Umbilical Cord Blood |
| Vasculogenesis |
Formation of primitive vascular networks from endothelial progenitors. |
| vWF |
von Willebrand Factor (a marker of endothelial cells) |
| YS |
Yolk Sac |
| Zygote |
Diploid cell of fusion between male and female gametes at fertilization. |
