Eosinophils, Basophils, Monocytes

what is the main cytokine used for differentation in eosinophils?

IL-5

what does a mature eosinophil look like?

bright orange granules

fewer nuclear lobes

where are the majority of eosinophils found?

in tissues

whats a special characteristic of eosinophils?

they are diurnal

dirunal

highest in morning and lowest in evening

what are the functions of eosinophils?

defend against parasitic infection

neutralize basophil and mast cell effects during allergic reactions

phagocytosis (limited)

why is it important that eosinophils neutralize basophil and msat cell effects?

prolonged sever inflammation can lead to tissue damage

how do we know that eosinophils were a part of the inflammatory response?

there are charcot-leyden (crystals left behind)

eosinophilia

an increase in eos

seen with allergic rxns, parasitic infection, and asthma

eosinopenia

decrease in eos

from stress

not clinically significant

what are the two cells that aren’t worth reporting their immature forms?

basophils and eosinophils

characteristics of basophils

slightly smaller

large purple-black granules

1-2 lobes for nucleus

granules can obscure nucleus

have IgE receptors

where are the majority of basophils found?

tissues

what is the main cytokine that controls basophils?

IL-3

where are mast cells found?

in the bone marrow and tissues

how are mast cells and basophils related?

they come from the same progenitor cell

what do the granules in basophils contain?

histamines

heparin

cathepsin G

what are the functions of basophils?

they are mediators of the IR

involved in hypersensitivity rxns (asthma, allergic rxns)

once IgE receptors are binded degranulation is activated

what is seen with degranulation?

all the chemicals are released and create the symptoms associated with hypersensitivity

basophilia

increase in basos

seen in leukemias

basopenia

decrease in basos

seen with hives and allergic rxns (all consumed)

mononuclear phagocytic system (MPS)

monocytes

macrophages/histiocytes

where are monocytes found

in the PB

where are macrophages and histiocytes found?

in tissues

order of maturation for monocytes

HSC → CFU-GM →CFU-M → Monoblast →promonocyte → monocyte → macrophage

how are monoblasts and promonocytes related?

very low concentration in bone marrow

indistinguishable in microscopy

charactersitcs of monoblasts

found in bone marrow (RARE)

large

lacy, pale blue nuclear chromatin

several nucleoli

agranulare blue gray cytoplasm

characteristics of promonocytes

found in bone marrow (VERY RARE)

irregular, indented nucleus

coarser nuclear chromatin

azurophilic granules

gray blue cytoplasm

characteristics of monocytes

largest mature cell

chewed gum look of nucleus

lacy chromatin

ground glass look for cytoplasm

vacuoles

characteristics of macrophages

found in tissues only

become enlarged

blue cytoplasm

prominent nucleoli

become different names based on location

(histiocytes = marrow)

function of monocytes

phagocytosis

antigen presenatation

monocytosis

increase in monos

intracellular bacteria

TB or salmonella

monocytic leukemia

increase in all stages of monos (severe infection)

phagocytosis from monocytes

slower but more efficient than segs

can be done repeatedly

cleans up debris

antigen presentation from monocytes

It is the by-product of phagocytosis

in innate and adaptive IR

cytokine production (interleukins)

attract neutrophils