Granulocytic Maturation

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Characteristics

-undergo the same developmental sequence as the neutrophil

-Cytoplasm has large granules that stain w acid dyes

-Complete Function unknown but some are

-attracted to antigen- ab complexes and capable of phagocytosis

-small numbers in acute and large numbers in chronic inflammation

-Antagonizes effects of histamine

-granules can damage larvae of helminthic parasites

-affected by diurnal variation because there's a higher amount at night

Eosinophilia & Eosinopenia

- Eosinophilia > 350 ul

-associated w elevated IgE

- allergies, collagen disease, parasitic infections

-Eosinopenia

-2ndary to steroids

Characteristics

-loaded w basophilic granules stain w basic dye

-granules have histamine, heparin and serotonin

Functions

-involved w immediate and delayed hypersensitivity

- during hypersensitivity, IgE attaches to surface and stimulates degranulation

- Basophilia associated w myeloproliferative disorders and hypersensitivity

Monoctye-Macrophage

-U or S shaped, lots azurophilic granules purple

-Development

-stays in BM 60 hrs-->peripheral blood monocyte for 70-100 hours--> travels to tissues (no recirculation)--> transforms into macrophage and lives months to years

Monocyte Development

Monoblast

-Shares common stem cell with myeloid cells- CFU-GM

-reticular lacy chromatin 1-2 nucleoli

-cytoplasm gray to cloudy blue w few red granules

- divides into a promylocyte

-3-4 cell divisions happen between monoblast and monocyte

Promonocyte

-round to oval w slight indented nucleus

-cyto grey to cloudy blue w a few red granules

-stains positive w non specific esterase

-matures into a monocyte

Monocyte

-slightly larger than neutrophil

- slight chromatin clumping, no nucleoli in nucleus, brain like convolutions

-bluegray cyto often w vacuoles

Microphage- cells that engulf small particles

macrophage- cells that engulf large particles

histiocyte-cells that have scavanger tissue fragments

Tissue Macrophages all from blood monocytes

Alveolar, splenic and peritoneal macrophages

liver kupffer cells

BM osteoclasts

microglial cells of the nerous system

Characteristics

-mature monocytes have enzymes like

-acid phosphotase, B glucoronidase, lysosome, lipase, peroxidase

- they secrete chemicals like interferon, interleukin 1, plasminogen activator, plasmin inhibitor, platelet activation fator, tissue procoagulant

Types of Monocytes

1. Classic Monicyte characterized by high expression of CD 14

2. Pro inflammatory monocyte w low level of CD 14 and receptors of CD16(from classic monos, more mature and produce high amnts of cytokines like IL1 and tumor necrosis factor)

Function

-debridement, senesent or damaged cells phagocytized

-host defense

-phagocytosis and microbial activity

-immune process- accumulates antigen in immunogenic form and

interacts w leukocytes

-tumor recognition and destruction

Monocytosis

-increased in malignancies

-increased in autoimmune disorders- RA, SLE, ulcerative colitis

-nutropenia may bring monocytosis

-chronic infection

-monocytic leukemia

-TB,leprosy, salmonellosis and brucellosis

Storage cell disorders- inherited disorders asso w enzyme deficiencies that result in the excess of undigested cellular products in macrophages, particularly from lipid rich

cell membrane

Gaucher's Disease

-Deficiency of B-glucocerebrosidase w the overload of glucoceramide. Macrophage becomes laden w fibrillar cytoplasmic inclusions

Niemann-Pick Disease

-one of the gangliosides, w deficient lysosome enzymes that lead to an accummulation of sphingomyelin or other lipid globules; foamy, vacuolated appearance of macrophage cytoplasm

Sea Blue Histocyte

-histocyte filled w globules of ceroid, an insoluble lipid pigment representing undigested globosides from cell membrane

Neutrophil Granules

Primary Granule

-non specific, azurophilic

-1st seen in the promyelocyte

-has lysosome that contains lytic enzymes capable of breaking down

proteins, carbs and nucleic acids

-the 2 enzymes present in primary granules are myeloperoxidase and

lysosome

Secondary Granule

-specific, basophilic, eosinophilic or neutrophilic

-contains lysozyme, lactofferin, alkaline phosphotase

-translocate material from cytoplasm to membrane, where it participates in

cell adherance, chemotaxis and initiation of respiratory burst

Function: Microbial Killing

Eisenophils

Basophils

Monocyte

Storage Cell Disorders

Neutrophils