Where does blood cell production, maturation, and death occur?
- In organs of the reticulendo-thelial system (RES)
- Bone marrow
- Lymph nodes
What are the functions of the RES (reticuloendo-thelial system)?
- Immune defense
Name the 3 phases of intrauterine hematopoiesis
- Mesoblastic (yolk sac) phase
- Hepatic (liver) phase
- Myeloid/medullary phase
What does the mesoblastic (yolk sac) phase produce?
Primitive nucleated erythroblast - which produces hemoglobins Portland, Gower I and Gower II
What does the hepatic (liver) phase produce?
- Mainly RBCs
- Hgb F
- Hgb A
- Hgb A2
What does the myeloid/medullary phase produce?
- Bone marrow producing mainly granulocytes
- Hgb F
- Hgb A
- Hgb A2
How much of the bone marrow is active for newborns, young adults, and older aldults?
- Newborns: 80-90% of bone marrow is active red marrow
- Young adults: 60% of bone marrow is active; hematopoiesis is confined to the proximal ends of large flat bones, pelvis, and sternum
- Older adults: 40% of bone marrow is active
What is the term for the ratio of marrow cells to fat (red marrow/yellow marrow) and is described in adults?
What is the cellularity of the marrow that has 30-70% hematopoietic cells?
What is the cellularity of the bone marrow that has >70% hematopoietic cells?
What is the cellularity of the bone marrow that has <30% hematopoietic cells?
What is the cellularity of the bone marrow with few or no hematopoietic cells?
What is the normal range of the M:E ratio?
3:1 and 4:1
What involves the production of pluripotential stem cells that develo into committed progenitor cells (lymphoid or myeloid) and finally into mature blood cells?
What do the lymphoid progenitor cells differentiate into?
B or T lymphocytes in response to cytokines/lymphokines/interleukins/CSFs/growth factors
What do the myeloid progenitor cells give rise to?
Gives rise to the multipotential progenitor CFU-GEMM (Colony forming unit granulocyte erythrocyte macrophage megakaryocyte), which will differentiate into committed progenitor cells and finally to mature blood cells in response to cytokines/interleukins/colony stimulating factors/growth factors
Where is the site of pre-B cell differentiation?
Where is the site of pre-T cell differentiation?
What are leukocytes classified as?
- Phagocytes (granulocytes, monocytes)
- Immunocytes (lymphocytes, plasma cells, monocytes)
Name the granulocytes
What do monocytes differentiate into?
- Macrophages - to work in the tissues to phagocytize foreign bodies
- Arrive after neutrophils and do NOT die in the process
What is the reference range for WBC?
4.0-11.0 x 109/L
Which cells are the first responders?
- Neutrophils are the 1st to reach the tissues and phagocytize bacteria
- They die in the process
What do T-Lymphocytes provide?
- Cellular immunity
- When activated, they proliferate and produce cytokines/interleukins
What do B-Lymphocytes develop into?
- Develop into plasma cells inthe the tissue
- Produce antibodies needed for humoral immunity
What do NK (natural killer) lymphocytes do?
Destroy tumor cells and cells infected with viruses
What else are NK (natural killer) cells known as?
Large granular lymphocytes (LGLs)
What do eosinophils do?
Modulate the allergic response caused by basophil degranulation
What do basophils do?
- Mediate immediate hypersensitivity reactions
- (type I, anaphylactic)
What are surface proteins expressed by specific cells lines at different maturation stages?
What is the term for blood cell production within the bone marrow?
What is the term for blood cell production outside the bone marrow?
Where does extramedullary hematopoiesis occur?
- Hepatomegaly or splenomegaly often accompany this
What does a nucleas contain?
- Chromatin composed of DNA and proteins
- Nucleoli rich in RNA
What forms lysosomes?
What do the lysosomes contain?
Hydrolytic enzymes that participate in phagocytosis
What assembles amino acids into protein?
What furnishes the cell with energy (ATP)?
What is a system of interconnected tubes for protein and lipid transport?