heme unit 2.2

Name WBC known to recirculate b!w blood and lymph

Lymphocyte

2 primary lymphoid organs

1. Bone marrow

2. Thymus

2 secondary lymphoid organs

1. Lymph nodes

2. Spleen

B lymphocytes

Origin = BM

Branch = hormonal

Lifespan = <5 days

T lymphocytes

Origin = thymus

Branch = cellular

Lifespan = months to yrs

Major function of lymphatic system

Collect and dispose of lymph

4 functions of spleen

1. Filtration

2. Cell grooming

3. Reservoir

4. Immunity

Final stage of B cell maturation

Plasma cell

Hof area

Clear zone next to nucleus in plasma cells

Lymphoblast

Cytoplasm:

• appears very smooth w/ no granules

• Moderate to dark blue

Nuclear:

• round/ oval

• Fine chromatin

• 1-2 distinct nucleoli

Prolymphocyte

Don’t need to know right now just where in series

Lymphocyte

Cytoplasm:

• prominent azurophilic granules

• Sky-blue in small ones

• Clear in large ones

• May BE indented BY RBCs

Nuclear

• round

• Clumped chromatin

• Darker color than myelocyte

3 major cells types in RES + organs seen in

1. Reticulum cells

   • spleen, lymph nodes, BM

2. Endothelial cells

   • spleen, lymph nodes, BM, liver

3. Free macrophages (or histiocytes)

   • spleen, BM, liver

5 general functions of RES

1. Phagocytosis

2. Antibody production

3. Hematopoiesis

4. Storage

5. Metabolism

Monoblast

Looks like any other blast

Need special stain to ID

Promonocyte

Just need to know where in series

Monocyte

Cytoplasm:

• irregular

• Blue-grey

• Fine azurophilic granules

• May indent RBCs

Nuclear

• shape varies

• Lighter color than WBCs

• Chromatin most “laciest”

Macrophage (tissue only)

Cytoplasm:

• abundant

• Blue to clear

Nuclear

• egg or bean shaped

• Appearance varies greatly

2 major functions of macrophages

1. Phagocytosis

2. Participation in immune response

   • trapping Ag processing a more antigenic form which stimulate antibody production