The hematologic system functions as
an important part of the body's defenses.
Hematopoietic
Blood forming
Identify the three types of white blood cells that are the result of hemopoiesis
Pluripotent stem cells, multi potent stem cells, & committed progenitor cells
Trace the development of the different blood cells from their origin in the pluripotent bone marrow stem cell (to lymphoid stem cell) to their circulation in the bloodstream
Pluripotent stem cell>lymphoid stem cell>
1.NK progenitor>NK cell
2.T cell progenitor>
thymus
>T cell
3.B cell progenitor>B cell>plasma cell
Trace the development of the different blood cells from their origin in the pluripotent bone marrow stem cell (to myeloid stem cell) to their circulation in the bloodstream
Pluripotent stem cell>myeloid stem cell>
1.Monocyte>Monoblast>Monocyte
2.Granulocyte>
Eospinophil, Neutrophil, or Basophil
3.Megakaryocyte>Megakaryocyte>platelets
4.Erythrocyte>Reticulocyte>Erythrocyte
Explain the meaning of pluripotent stem cell and colony-forming unit (CFU).
-Pluripotent stem cells: give rise to 2 types of multi potent stem cells (the hematopoietic (common myeloid) stem cells(remain in bone marrow) & the lymphopoietic (common lymphoid) stem cells (migrate to the lymphoid tissues))
-Colony-forming unit (CFU):
Identify the two types of cells that arise from pluripotent stem cells.
Common lymphoid stem cells & common myeloid stem cells
Discuss the role of cytokines and colony-stimulating factors in the regulation of blood cells.
-Cytokines: short-lived mediators that stimulate the proliferation, differentiation, & functional activation of the various blood cells
-Colony-stimulating factor: they have only limited capacity for self-renewal but retain the potential to differentiate
Explain the difference between lymphoid and myeloid stem cells and identify the cells that arise from each.
-Lymphoid stem cells: migrate to the thymus, lymph nodes, spleen, & mucus-associated lymphoid tissues [consists of the following cells:(T cell)(NK cell)(B cell)(plasma cell)]
-Myeloid stem cells: remain in the bone marrow [consists of the following cells:
Learning Objective 3.
List the three types of white blood cells and briefly describe their function.
-Granulocytes: phagocytic cells
-Lymphocytes: migrate through peripheral lymphoid organs where they recognize antigen & participate in immune responses
-Monocytes: travel from bone marrow to body tissues, where they differentiate into various tissue phago
Learning Objective 4. List the three subtypes of granulocytes and briefly describe their role & their % composition of total WBCs
-Neutrophils: primary antigen-fighting cells
(60-65% total WBCs)
(Nuclei divided into 3-5 lobes)
-Eosinophils: help control allergic reactions & fight parasites
(1-3# of total WBCs)
(Many bright red-stained granules)
-Basophils: secrete heparin, histamine
Learning Objective 5. Describe the role of the lymphoid tissues.
(Using examples, explain the difference between central and peripheral lymph organs)
-The body's lymphatic system consists of the lymphatic vessels, lymphoid tissue & lymph nodes, thymus, & spleen.
-T lymphocytes migrate to peripheral lymphoid structures to complete the differentiation process: they leave bone marrow as precursor T lympho
Lymphatic vessels functions
prevent edema by moving fluid and proteins from interstitial spaces to venous circulation; they also reabsorb fats from the small intestine.
Lymph nodes
�are tissues that filter out bacteria and other foreign cells and are grouped by region.
�are grouped by region: cervicofacial, supraclavicular, axillary, epitrochlear, inguinal, and femoral.
The spleen
destroys bacteria, filters blood, serves as a blood reservoir, forms lymphocytes and monocytes, and traps formed particles.
Hematopoiesis (occurs in) (& the process)
�Occurs in the spleen
�is the process by which red blood cells, white blood cells, and platelets are produced.
Hematopoiesis is carried out by red bone marrow. & Bone marrow contains...
stem cells, which may develop into several
different cell types during hematopoiesis.
Erythrocytes (red blood cells [RBCs])
Are formed in the bone marrow and contain hemoglobin.
List the blood cells that arise from each of the two types of lymphoid tissue.
�Lymph Nodes: cortex contains well-defined
B cell
&
T cell
l* domains.
--superficial outer cortex: aggregates of cells called "follicles">> are the B cells zones of the lymph nodes
>>2 types: immunologically inactive follicles (primary follicles) & active
Neutropenia
Refers specifically to an abnormally low # of neutrophils & is commonly defined as a circulating neutrophil count of <1500 cells/mcgL
Mild Neutropenia
1000 cells/mcgL
Moderate Neutropenia
500-1000 cells/mcgL
Severe Neutropenia
<500 cells/mcgL
Leukopenia
Decrease in the absolute number of leukocytes in the blood
Granulocytopenia/Agranulocytosis
Denotes a virtual absence of neutrophils
Aplastic anemia
All of the myeloid stem cells are affected, resulting in anemia, thrombocytopenia, & agranulocytosis
Learning Objective 7. Cite two general causes of neutropenia.
Identify causes of neutropenia. (Refer to Chart 11-1.)Learning Objective 8. Describe the mechanism of symptom production in neutropenia.
For each cause, list the effect on neutrophils that resu
�Congenital
-alloimmune neonatal neutropenia (transfer of maternal antibodies)
- cyclic neutropenia (autosomal disorder w/ variable expression that in infancy & persists for decades)(develops every 21 days & lasts ~2 to 3 days)
- Kostmann syndrome (severe
Idiosyncratic
Describes drug reactions that are from different from the effects observed in most persons and that cannot be explained in terms of allergy
Many idiosyncratic cases of drug-induced neutropenia are thought to be caused by...
Immunologic mechanisms, w/ the drug or it's metabolites acting as antigens (haptens) to incite the production of antibodies reactive against the neutrophils
Learning Objective 9. Define infectious mononucleosis and describe the pathogenesis, clinical manifestations, and treatment.
Explain the cause of infectious mononucleosis and cite its prevalence.
Describe the pathology, clinical course, typical lab result
Viral illness caused by the Epstein-Barr virus, a B-lymphotropic herpes virus.
? Most cases spread by the oropharyngeal route, but transmission by blood transfusion or during cardiac surgery is also possible.
? The virus invades the B cells of the orophar
Leukemia
Refers to a group of malignant disorders characterized by abnormal proliferation & maturation of lymphocytes & nonlymphocytic cells, leading to the suppression of normal cells
�it can be classified as acute or chronic, w/ sub classifications of lymphocyti
Leukemia: how it happens
�Hematopoietic cells (immature blood cells) undergo an abnormal transformation, giving rise to leukemic cells.
�Leukemic a multiply & accumulate, crowding out other cell types
�Crowding prevents production of red & white blood cells & platelets, leading t
Pancytopenia
Reduced number of all cellular elements of the blood
Acute lymphocytic leukemia
Abnormal growth of lymphocytic precursor (lymphoblasts)
Acute myelogenous leukemia
Rapid accumulation of myeloid precursors (myeloblasts)
What to look for in Acute (lymphocytic or myeloid) leukemia
(Related to suppression of elements of the bone marrow)
�anemia
�bleeding
�fever
�infection
�night sweats
�weight loss
�paleness
�lethargy
�malaise
The initial phase of chemotherapy for acute lymphocytic leukemia, called the induction phase,
is designed to put the client into remission by giving high doses of drugs and administering doses closer together than once each month.
complications of acute leukemia and its treatment:
leukostasis
is a condition in which the circulating blast count is markedly elevated (usually 100,000 cells/mcgL). The high number of circulating leukemic blasts increases blood viscosity and predisposes to the development of leukoblastic emboli with obstruction of s
complications of acute leukemia and its treatment:
tumor lysis syndrome
...
complications of acute leukemia and its treatment:
hyperuricemia
occurs as the result of increased proliferation or increased breakdown of purine nucleotides (i.e., one of the components of nucleic acids) secondary to the leukemic cell death that results from chemotherapy. may increase before and during treatment.
�Tx:
complications of acute leukemia and its treatment:
blast crisis
...
Chronic lymphocytic leukemia shows
a proliferation of small abnormal mature B cells and decreased antibody response.
Uncontrolled proliferation of granulocytes
occurs in myelogenous
leukemia
Hodgkin lymphoma (HL)
...
In stage I of Hodgkin's disease, symptoms include
a single enlarged lymph node (usually), unexplained fever, night sweats, malaise, and generalized pruritus.
non-Hodgkin lymphoma (NHL)
...