WBC Profiles

plasma -- most plentiful component

--> water, proteins, antibodies, hormones

RBCs

Buffy coat (platelets/WBCs)

components of blood

Innate immunity

nonspecific defense mechanisms that are present at birth, and come into play immediately or within hours of an antigen's appearance in the body; does not require prior exposure

epithelial barrier

HCl

lysozyme (breast milk, saliva, tears)

mucous membranes (GI, respiratory tract)

what are some examples of the non-cell mediated components of innate immunity?

neutrophils, basophils, eosinophils, monocytes/macrophages

what are some components of the cell-mediated innate immune response?

Granulocytes

a group of leukocytes with granules present in the cytoplasm; they often have a multi-lobed nucleus and originate in the bone marrow; major players in innate immunity

neutrophils, eosinophils, basophils

examples of granulocytes

adenoids, tonsils, thymus, spleen, lymphatic vessels, lymph nodes

organs/body structures involved in the immune system

Adaptive immunity

immunity that is constantly being refined throughout a person's life; it is not present at birth; and is characterized by a slower, antigen-specific response to pathogens; provides "memory" of response for future exposures

B cells and T cells

monocytes also play a role

cell-mediated components of adaptive immunity

Agranulocytes

leukocytes with non-lobular nuclei; no granules in the cytoplasm; originate in the lymphoid tissue; they are major players in adaptive immunity that arrive later, have a greater capacity to consume more foreign pathogens, and live a LONGER LIFE!

Granulocyte macrophage colony-stimulating factors

what is responsible for stimulating maturation of leukocytes?

Complement

series of 60+ plasma and surface proteins that are produced by the liver; first line of defense against invading pathogens; enhances other WBCs; can be activated independently

to "complement" the other WBCs

function of complement

Alternative pathway

complement pathway responsible for attracting other leukocytes and encouraging phagocytosis

Lectin pathway

complement pathway responsible for triggering inflammation

Classic pathway

complement pathway responsible for damaging the cell membrane of the pathogen via "pores" (MAC)

phagocytes start to arrive to the area and consume foreign material until they themselves die (pus)

once complement is activated, what occurs next?

pyogenic infections

neutrophils are responsible for responding to what kind of stimuli?

allergic disorders, parasites

eosinophils are responsible for responding to what kind of stimuli?

parasitic

basophils are responsible for responding to what kind of stimuli?

Neutrophil

most plentiful phagocytic granulocyte; produced by bone marrow, circulate for about 8 hrs, then proceed to tissues; first cells to arrive at site of infection/inflammation; responsible for phagocytosis of extracellular pathogens

bacterial infections

neutrophilic can be seen in what conditions?

Band neutrophils

immature neutrophils

Eosinophil

phagocytic granulocyte that is elevated to play a role in the allergic response along with mast cells; can also elevate in response to parasites; they are produced by the bone marrow, circulate for about 18hrs, then move to thymus and GI tract

segmented neutrophils

mature neutrophils

parasitic infxns

allergic reaction

asthma

atopic dermatitis

eosinophilic esophagitis

eosinophilia can be seen with what conditions?

Basophil

least numerous of all the NON-phagocytic granulocytes that are increased in parasitic infections; they are produced by the bone marrow and circulate the blood treatment; this cell type contains granules secrete many potent immune modulators (histamine, interleukins, heparin)

parasites (helminths)

malignancy (AML, CML, myeloproliferative disorders, polycythemia vera)

inflammation (IBD, RA, UC)

allergy (asthma, allergic rhinitis, food allergy)

basophils are increased in what conditions?

Mast cells

NON-phagocytic granulocyte that resides in large number sin peripheral tissues (not present in blood); contains IgE receptors; releases histamine, serotonin, heparin, leukotrienes, platelet-activating factor; activates basophils/eosinophils; interacts with B/T cells, dendritic cells, via MHC proteins.

vasodilation and bronchoconstriction

the substances secreted by mast cells cause what physiologic effects?

Monocyte

agranulocyte that originates in the bone marrow and circulates for 5-8 days before entering the tissues; these cells are capable of processing foreign antigens and presenting them to the immunocompetent lymphocytes

enter the tissue where it is transformed into a macrophage

remain in circulation as monocytes

acted upon by cytokines to turn them into dendritic cells

*can change back into monocytes if leaves tissues

what are the 3 potential fates of a monocyte once it develops?

Dendritic cells

major antigen presenting cell that is the key link between the innate and adaptive immune system; functions in capturing, processing, and presenting antigens to T-cells; start as innate cells but as they mature begin to develop specificity for antigens

viral

lymphocytes respond to what kind of infections?

B cells, T cells, NK cells

types of lymphocytes

B-lymphocyte

major players in humoral immunity that are made in the bone marrow; they have antigen-specific receptors but they cannot directly attract infected cells, they work instead of creating antibodies; when it meets its receptor's match, it secretes Abs

Plasma B-cells

short lived cells that disappear once immune response is finished; not normally present in blood; can be seen with some disease processes

Multiple myeloma, cancers, arthritis, lupus

plasma cells can be seen in the blood in what immune processes?

Memory B-cells

Produced during a B cell response, but are not involved in antibody producing during the initial infection; are held in reserve for the rest of your life in case you encounter that pathogen again.

T-lymphocyte

lymphocyte that is made in the bone marrow but matures in the thymus; only recognizes "processed" antigens by APCs

Helper T cells

T cells that secrete cytokines that attract macrophages, neutrophils, activate B cells; also directs the cells once they arrive

Cytotoxic/Killer T cells

T cells that destroy infected cells, tumor cells, or any other cells which show signs of damage

Memory T cells

T cells that persist post-infection; liver longer than memory B cells and rapidly proliferate if re-exposure occurs.

Natural killer cells

lymphoid cells that do not have antigen specific receptors making them part of the innate immune system; can alter their behavior based on prior exposure to particular antigens; contain granules that released, damage the cell membranes of its target and induce apoptosis; relies on MHCs to avoid targeting healthy cells

CBC w/o diff

measure of mature cells; does NOT tell you if you have more of one specific type of WBC or if you have immature WBCs called bands

the body recognizes infection but cannot produce enough mature cells to effectively fight the infection

release immature cells to do a mature cells job

the presence of bands on bloodwork indicates...

CBC with differential

total number of WBCs that provides the percentage of each cell type present; normal ranges are 2 standard deviations above/below the mean

Leukocytosis

WBC > 11,000 that is usually caused by an increase of only one type of leukocyte

N -- bacterial infxn

E -- allergy, parasite

B -- parasite, malignancy, allergy

L -- viral infxn

what do increases in neutrophils, eosinophils, basophils, and lymphocytes indicate?

hemoconcentration -- look for dehydration

if there is an increase in all cell types in a CBC with differential, what could be the cause?

any stressful or infectious process

what can cause a leukocytosis?

Trauma or tissue injury (surgery)

Med side effect -- glucocorticoids

Leukemia/myeloproliferative disorder

what are ones non-infectious causes of a leukocytosis?

stress, excitement, pregnancy, pain, anesthesia

if one has a leukocytosis without evidence of clinical disease, think...

Neutrophilia

Neutrophils >7700/microL

infection

inflammation

medictions

asplenia

smoking

stress/exercise

obesity

endocrine causes

causes of neutrophilia

clumped platelets

what lab error can result in a falsely high neutrophil count?

6%

up to __ bands is normal

Regenerative left shift

neutrophilia with some bands; commonly seen with acute bacterial infections; GOOD prognosis!

Degenerative left shift

neutroPENIA with bandemia; POOR prognosis :(

Right shift

few bands, more mature cells; increased segmented neutrophils (hyperhsegmented neutrophils)

megaloblastic anemia, liver disease, cancer, drugs, allergies

resolving infection

causes of a right shift

Leukemoid reaction

WBC count >50,000; can be myeloid or lymphoid; excess of MATURE WBCS; because of similar presentations, ALL/AML needs to be RULED OUT!

stress/infection

--> infection (TB, Cdiff, pertussis, mono)

--> drugs (steroids, all-trans retinoic acid)

--> asplenia

by definition, leukemoid reactions are due to...

Leukopenia

total WBCs <4000

Viral or overwhelming bacterial infection

Leukopenia is TYPICALLY caused by...

Problem with bone marrow (disease, nutritional deficiency, medications)

other causes of leukopenia other than infection

avoid fresh fruits/veggies due to possible food contamination

avoid IM injections, rectal temps, enemas/suppositories, or razor blades

what are some clinical tips for leukopenia?

Neutropenia

low neutrophil count; <1500 ANC

infection -- EBV, HIV, hepatitis, bacterial/parasitic infections

Medications -- rituximab

Nutritional -- B12, folate, copper deficiency

Malignancy

Rheumatologic

Autoimmune

causes of neutropenia

observe with repeat lab in a few weeks

education on neutropenic precautions

--> monitor for infxn, good hygiene, avoid crowded areas, avoid unwashed raw fruits/veggies, unpasteurized foods, identify possible causes

treatment for neutropenia if the pt is asymptomatic and ANC >1000

admission for abx

neutropenic precautions

evaluation for underlying etiology

consult with heme

Severe -- <500/microL

treatment for neutropenia if the pt is symptomatic

Atypical lymphocytes

irregularly shaped and/or have irregular amounts of granules in their cytoplasm

INFECTIOUS MONONUCLEOSIS -- DOWNEY CELLS

can also be caused by CMV, hepatitis, tuberculosis

causes of atypical lymphocytes

Dohle bodies

small blue cytoplasmic inclusions in neutrophils; presence can be normal in small numbers; increased numbers can indicate disruption in WBC production

infections

inflammation

leukemia

myeloproliferative diseases

causes of Dohle bodies

LE cells

red-purple inclusions distending from the cytoplasm; a neutrophil/macrophage that has phagocytize denatured material from another cell; NOT NATURALLY OCCURRING!!!

SLE or other autoimmune disease

chronic hepatitis, drug reactions

causes of LE cells

Hypersegmented neutrophils

mature neutrophil that has more than 5 distinct lobes

megaloblastic anemia

can indicate long term chronic infection

causes of hyperhsegmented neutrophils

Auer bodies

rod-like structure in the neutrophil; composed of fused lysosomes; can be seen in myeloid blast cell phase

AML

causes of Auer bodies

Pelger Huet anomaly

neutrophils develop with dumbbell shaped nucleus

myelodysplastic syndroems

Acute/chronic leukemias

causes of Pelger Huet anomaly

Smudge cells

lymphocytes that look flattened/smudged when a peripheral smear is obtained; these cells are fragile and are easily distorted when cover slide is placed on the sample

CLL

causes of smudge cells