Hematopoiesis

Hematopoiesis
from pluripotent stem cells to mature, differentiated, cellular effectors of immunity and more
Richard A. Poirier for HHMI/Harvard Immunology Summer Project 2004

Click on one of the following effector cells to see the sequence of different cells that lead to its production • • • • • • Th- Helper Cell B Cell Macrophage Neutrophil (alternative path) Mast Cell Platelets • • • • •• Tc Cytotoxic Cell Dendritic Cell Neutrophil Eosinophil Basophil Erythrocyte

T - helper cell pathway

Pluripotent Stem Cell
This is the undifferentiated precursor to all of the blood cells, red and white, and other immune effector cells, and platelets.

Lymphoid Stem Cell
Daughter cell of the Pluripotent Stem Cell, this cell will divide to produce progenitors to either B cell or Tcell lines .

T cell progenitor

leaves the bone marrow and settles in the thymus; will produce Thymocyte cells in the thymus which can, in turn differentiate into T helper cells, T killer cells, or T memory cells

The Thymocyte is located in the thymus
and divides to produce mature T effector cells….. Th (helper)Tc (cytotoxic-killer) or Tm (memory)

Th (helper) cell…when activated by anAntigen Presenting Cell like a macrophage with antigen, the Th cell will induce rapid growth of white blood cells which help fight infection

Click HERE to return to menu

Tc (cytotoxic/”killer”) cell pathway

Pluripotent Stem Cell
This is the undifferentiated precursor to all of the blood cells, red and white, and other immune effector cells, and platelets.

Lymphoid Stem CellDaughter cell of the Pluripotent Stem Cell, this cell will divide to produce progenitors to either B cell or T cell lines .

T cell progenitor

leaves the bone marrow and settles in the thymus; will produce Thymocyte cells in the thymus which can, in turn differentiate into T helper cells, T killer cells, or T memory cells

The Thymocyte is located in the thymus
and divides to produce matureT effector cells….. Th (helper)Tc (cytotoxic-killer) or Tm (memory)

Tc (cytotoxic or “killer”) Cells…
Sometimes called CTLs (cytotoxic T lymphocytes, these may recognize infected “self” cells and destroy them.

Click HERE to return to menu

B cell pathway

Pluripotent Stem Cell
This is the undifferentiated precursor to all of the blood cells, red and white, and other immuneeffector cells, and platelets.

Lymphoid Stem Cell
Daughter cell of the Pluripotent Stem Cell, this cell will divide to produce progenitors to either B cell or T cell lines .

B Cell progenitor…found in the bone
marrow of higher vertebrates and the Bursa of Fabricius in birds, these cells will produce antibody producing B cells.

B Cells… these are found in the blood and ,
when activated willproduce antibodies against particular antigens. Each cell produces antigen specific antibodies of only one type.

Click HERE to return to menu

Dendritic cell pathway

Pluripotent Stem Cell
This is the undifferentiated precursor to all of the blood cells, red and white, and other immune effector cells, and platelets.

Myeloid Stem Cells… daughters of the
Pluripotent Stem Cells,these are the progenitors of a host of specialized white blood cells (WBCs), red blood cells (RBCs) and the blood platelets which are crucial to blood clotting.

Granulocyte -Monocyte Progenitor cells
can differentiate into monocytes or neutrophils

Monocytes… act as antigen presenting cells
(APCs), as Antibody-Dependent Cytotoxic Cells (ADCC) , and promote inflammation.

Dendritic Cell…like the macrophage, this
cell is phagocytic it inhabits the tissues looking for foreign intruders to devour.

Click HERE to return to menu

Macrophage pathway

Pluripotent Stem Cell
This is the undifferentiated precursor to all of the blood cells, red and white, and other immune effector cells, and platelets.

Myeloid Stem Cells… daughters of the
Pluripotent Stem Cells, these are...