unit 3 hem sum

leukocytes

wbc, circulate in pb and move into tissues to respond, innate- granulo and mono phage, adap- mono and lymph, allergic and hypersens- eosin and baso

leukocytes surface markers

change with cell lineage/ subsets, stages of maturation, and state of activation, used for immunophenotyping

immunophenotyping

id markers with specific antibodies, cluster of differentiation CD number = specific cell surface molecule

leukocytes concentration

affected by age and pathology (infection, immune reg, and quantitative and qual disorders), high wbc = leukocytosis, low= leukopenia

leukocytes ref ranges

birth 9-30, child 4.5-13.5, adults 3.6-10.6, normal does not rule out disease

abnormal wbc count

manual wbc differential, enumerate each type within total of 100 cells, reported as %, check absolute count

absolute count

diff count as decimal x wbc

neutrophils percentage of wbcs

newborn 50-60%, 5 months to 6 years 30%, adult 50-70% (95% mature segmented, less that 5% bands)

neutrophils regulation by

IL-3, GM-CSF, G-CSF

neutrophils maturation or granulopoiesis

myloblast > promyelocyte > myelocyte > metamyelocyte > band > segmented neutrophil = polymorphonuclear PMN

signs of neutrophil maturation

nucleoli disappear, chromatin condense, nuclear mass indents and segments, cytoplasm becomes pink-neutral staining

myeloblast

1st rec precursor, 14-20 um, high N:C, nucleus- round or oval, delicate, lacy, evenly stained, nucleoli, small amount of blue agranluar cytoplsm

promyelocyte

15-21 um, high N:C, more coarse blase, nucleoli, cytoplasm- basophilic red-purple (azurophilic graniles), granules-peroxidase and antimicrobial compounds

neutrophil primary

azurophilic, MPO, defensins, lysosomal enzymes, kill and digest microorgan

myelocyte

last stage with mitosis, 12-18 um, smaller nucleus, more condensed chromatin, if late more tan-pink cytoplasm, 2ndary specific granules peroxidase neg, secretory vesicles

secretory vesicles

formed by endocytosis, fuse with plasma membrane to increase surface area and express receptors for pathogen attack, in mylocyte

neutrophil secondary

specific, lactoferrin, lysozyme, restrict bac growth, damage bacterial cell walls

metamyelocyte

10-18 um, kidney bean nucleus, pink-neutral cytoplasm, secondary and secretory granules, begin tertiary granules synthesizing

neutrophil tertiary

gelatinase, break down extracellular matrix to support tissue migration

band

first stage found normally in pb, 9-15 um, c u nucleus, pink-tan cytoplasm with 4 types of granule, increased = left shift

seg

9-15 um, 3-5 lobes connected by fine filament, pink-tan-colorless cytoplasm, 2ndary tertiary secratory granules, lipids carbs proteins

nucleus and cytoplasm maturation signs

nucleoli disappear > condense chromatin > indents > seg

blue/agranular > azuropholic granules > specific granules > pink-tan

neutrophils in bm- mitotic pool

3-6 days, 4-5 cell divisions, proliferation, myeloblasts, promyelocytes, myelocytes

neutrophils in bm- postmitotic pool

5-7 days, maturation and storage, metamyelocytes, bands, segs, 3x size of other pool

neutrophils in bm- increase need for neutrophils

released quickly from bm reserve, 3x larger than peripheral blood compartment, stimulates marrow precursors, higher proportion of less mature neutrophils released

neutrophils in pb

2 pools in eq (freely exchange), half in circulating pool CP, half in marginating pool MP- slowly roll along endothelial surface, 7.5 hrs then released to tissues- Diapedesis

neutrophils- tissue

from MP to respond to chemotaxic stimulation, die by trauma or apoptosis in 1-2 days if not stimulated by GM-CSF, phage by macroph if senescent

neutrophils kinetics

change in pb leukocytes is first sign of pathology, high = redistribution or high production, neutrophilia

agranulocytosis, granulocytosis, granulocytopenia

lack of granules, lot, less

neutrophils functions

get to site, engulf, murder,

adhere, migration chemotaxis, phag, bacteria killing

selectins

help neutrophils roll along endothelium to leave bv, stage 1 and 2

integrins and IgG

create firmer adhesion to neutrophils to leave bv, stage 3 after rolling

diapedesis

move neutrophils into tissues by squeezing between endothelial cells out of bv, stage 4

neutrophils phagocytosis

rec and attach with opsonins (IgG and C3b), phagosome (engulfed pathogen), phagolysosome (primary granules- lysome fused with phagosome, kill with granule enzymes and resp burst)

neutrophils extracellular traps NET

web structure of DNA and antimicrobial proteins from primary or 2ndary granules and cytoplasm, traps microbes outside cell, can cause inflam and tissue dam, lytic and non lytic (yeets the nuc)

neutrophil ref range

1.7-7.5

50-70%

eosinophils

0-5% of wbc, IL-5 (t cells), bm and stored 9 days, 12-15 um, 2 lobed nucleus, granules- large packing cytoplasm

eosinophils function

inflam, cytotoxic cytokines, allergy, asthma, hypersensitivity, parasite (protozoan, helminths), phyagocyte, ag-present, down reg allergic reaction (inactivate baso/mast cell mediators)

eosinophils specific granules contents

MBP EPO ECP

eosinophils kinetics

18 hrs in pb, weeks in tissues

eosinophils ref range

0-0.3 or 1-3%

high= eosinophilia, allergies, asthma, GI disease, parasites

basophils

least common wbc 0-1%, 10-15 um, large basophilic granules hide nucleus, water soluble- rinse away on wright stain, mast cells

basophil function

IgE binds causing degranulation releasing histamine and herparin (inflammation/anticoag)= allergy/anaphylaxis, immediate hypersens

basophil kinetics

bm 2-7 days, hours in pb

basophil ref range

0-0.2 or 0-2%

high= basophilia, rare, malignancy

mast cells

migrate to tissues, skip peripheral blood, same pathway as basophils

monocytopoiesis

monoblast and myeloblasts cannot be diff in bm, monoblasts and promonocytes low in bm, production is elevating in leukemia due to mononuclear phagocyte system MNP

monocytes become macrophages

stimulated by t cells and endotoxins, MNP in tissues

monocytes

12-20 um (largest), loose lacy chromatin in nuc, folded, horseshoe, lobular nucleus, blu-gray cytoplasm with FINE granules, vacuoles (increase with infec)

macrophage

in tissue, 15-80 um, months in liver= Kupffer, lungs= alveolar mac, skin= langerhans, brain= microglial, net like round nucleus, nucleoli, blue-gray irregular edge cytoplasm, vacuoles

mono/macro kinetics

bm- no storage pool, released within a day of maturation, pb- marginated and circulating pool for 8 hrs before diapedese into tissue

mono/macro function

innate and adap, MNP, nonspecific killing, clean up old cells, recycle iron, ag-present, produce cytokines

monocyte azurophilic granules/lysosomes

hydrolytic and digestive enzymes, digest microorganisms, damaged cells, and debris

monocyte ref range

0.1-1.3

2-11%

high= monocytosis

CLP

lymphoblasts > polymphocyte > NK, T, B (plasm)

lymphocyte functions

recognize and react with specific ag, work with pathogens to eliminate macrophages, provide long lasting immunity to previously encountered pathogen

nk

effector of innate (cytotoxic), kill tumors and pathogen infected, CD16+, 56+, no tcr, develop in bm

b cells

present ag to t cells, become secreting plasma cells, produce ab specific to one ag by rearranging its Ig genes

ag independent lymphopoiesis

primary lymphoid tissue, CLP cell (immunocompentent naive t and b), migrate to 2ndary tissue

ag dependent lymphopoiesis

once immunocompetent b or t rec ag, produce effector t and b, drives adaptive

somatic recombination

receptor to ag diversity by V(B)J gene rearrangement, terminal deoxynucleotidyl transferase TdT (adds random nucleotides where v d j segments join)

B lymph membrane markers

CD19 (latest stages of activation), slg (surface Ig)- IgM and D on mature niave, IgG A E on activated cell (class switch)

constant region vs variable

same for all ab in class vs diff for all ab

B1

in body cavities, mucosal sites, secrete ab withoyt known prior exposure (natural), IgM (broadly reactive, common microbial and self-ag)

B2

produced in bm after birth, in pb and 2ndary tissues

t in thymus

mature into naive, tested against self, activity declines with age

MHC I

HLA-A, B, C, nucleated cells to CD8

MCH II

HLA-DP, DQ, DR, APCs to CD4

TCR

made form alpha-beta chains or gamma-delta chains

single pos thymocyte

mature, naive CD4 (lymph nodes, 60-80% in pb) or 8 (bm, 35% in pb), leaves thymus to pb for further maturation

morphology of lymphocytes

identical so check surface markers and molecular testing for gene rearrangement, stages of maturation (lymphoblasts, prolymphocytes, lymphocyte)

lymphoblast

10-18 um, high N:C, nucleus- lacy, fine, smudged, pale blue nucleoli, dense membranse, perinuclear clear zone, cytoplasm- agranular, less baso than other wbc

prolymphocyte

difficult to diff in normal bm, smaller than lymphoblasts, lower N:C, nucleus- chromatin condensed and clumped, nucleoli present, cytoplasm- light blue, agranular

small lymphocyte

7-10 um, nucleus- size of rbc, 90% of the cell, deeply condensed chromatin purple, cytoplasm- small rim sky blue, azurophilic granules, vacuoles, responds to ag binding becoming large

large lymphocyte

11-16 um, nucleus- larger, less clumped chromatin, cytoplasm- lighter blue with peripjeral basophilia, azurophilic granules

large granulat lymph LGLs

Nk cells (CD3-) and activated cytotoxic t (CD3, 8), nucleus- round or indented, cytoplasm- abundant pale blue, coarse pink granules (serine proteases causing apoptosis)

activated lymphs are classified as

reactive t or b OR t or b immunoblast, both can becomoe effector or memory

reactive lymph facts

stimulated, transformed, atypical, activated, variant, variety of mophology, few in healthy pb (increase with viral infec), differentiate into immunoblast, effector, or memory

reactive lymph morph

huge 16-30, low N:C, nucleus- stretched, irregular, dispersed chromatin, nucleoli?, cytoplasm- high basophilia (diffuse and concentrate), azurophilic granules?, vacuoles?, indented by nearby rbc hugging?

immunpblasts t or b

actively proliferating clonal amplification, in lymph tissue rarely pb, increased size, nuc, cytoplasm, nucleus- fine chromatin, nucleoli, cytoplasm- intense blue, RER

immunoblast B

produce ag specific daughter cell sthat become effector plasma cells, and memory that look like sm lymph

immunoblasts T

produce ag specific dc becoming effector helper cytotoxic and memory b cells

plasma cells

round/oval, 14-20 um, nucleus- eccentric (going somewhere), coarse blocklike radial chromatin masses (cartwheel), cytoplasm- golgi apparatus= hof (clearing), high, deep basophilic, azurophilic

lymphocyte ref range

1-3.2

18-42%

high- lymphocytosis, low- lymphopenia

lymphocytes kinetics

5% in pb (80% are longlived memory months to years, 20% hours to 5 days), 95% in extravascular tissue of lymph nodes and spleen, continuously move between these

alterarion in Ig production

detected by protein electrophoresis

hypogammaglobulinemia- decrease, polyclonal gammopathy- increase in more than one class, monoclonal gammopathy- increase in specific class with hc and lc ID

aging of lymph system

thymus atrophies to 15% of maximum size, less able to distinguish self from non self (increasing autoab production), net effect (slower less efficient to new ag)