1. Immune Functioning

3. Major structures for immune
functioning
 Lymph nodes – small organs
throughout the body designed to
receive fluids from peripheral tissue
sites. Clusters found in many areas
 Spleen – the largest lymphoid organ.
Supports humoral immune response
to blood-borne pathogens. Also
assists in filtering for damaged RBCs

4. Major structures
 Thymus - contributed to the
maintenance and functioning of
T-cells
 Bone Marrow – generates
pluripotent stem cells for cell
generation including RBCs,
WBCs, antibody production
 Blood – houses RBCs, WBCs
and platelets

5. “Shift to the left”
is the release of
immature
neutrophills to
fight infection

6. WBC Functioning
 Granulocytes – neutrophils,
eosinophils and basophils
 Nongranulocytes – lymphocytes
and monocytes

7. Cellular WBC response as seen
on a CBC differential
 Neutrophils – one of the most
plentiful along with lymphocytes
 55-70% of differential smear
 Most (90%) remain in the bone
marrow for storage
 Neutrophils in circulation also adhere
to endothelial lining of small blood
vessels
 1st on the scene for inflammatory
response (usually within 6-12 hrs)

8. Cellular WBC response
also trauma
 Elevated with acute and surgery
inflammatory reaction or acute
infection
 Survive for only 24-48 hrs
 “segs” refer to mature cells
 “bands” refer to immature

9. mature
immature

10. Lymphocyte activity
 Total lymphocytes accounts for
20-40% of differential smear
 T-lymphocytes (mature in
thymus)
 B-lymphocytes (mature in bone
marrow)
 T Cytotoxic (CD8)
 T Helper (CD4)
 NK cells

11. Lymphocytes
 T-lymphocytes primarily involved in
cell-mediated immunity, serve as NK
cells and T4 helper cells
 B-lymphocytes primarily and humoral
immunity
 The lymphocytes circulating in the
blood are primarily responsible for
fighting chronic bacterial and acute
viral infections
i.e. long
standing i.e. rhino virus
pneumonia or
celleulitis

12. Cellular WBC response
 Monocytes – triggered by
chemotactic factors becoming a
macrophage in lung, connective or
lymphoid tissue to remove foreign
substances by phagocytosis
 Arrives on site within 3-7 days
 4-8% of diff smear
 Elevated in long-standing
infections
 Produces interferon, the body’s own
immunostimulant

13. Cellular immune response
 Eosinophils – very small
percentage seen in the WBC
count (1-4% of diff smear)
 Elevated in parasitic
infections and IgE-mediated
allergic responses
 Do not respond to bacterial
infections

14. Cellular immune response
 Eosinophils – house heparin,
histamine and serotonin in the
cytoplasm
 Eos infiltrate the tissue affected
by allergy to further the
inflammatory reaction

15. Cellular immune response
 Basophils – only 1-2 % of
differential smear
 Also supports IgE-mediated
allergic responses

16. Cells identified in the WBC
differential

17. leukocytosis=too
WBC differential many white blood
cells
 Total WBCs (leukocytes)
5000-11000/mm3
 Neutrophils 50-70%
 Lymphocytes 20-40%
 Monocytes 4-8%
 Eosinophils 0-4%
 Basophils 0-2%

18. Human Immunity
 Direct (active) immunity
 Indirect (inactive) immunity
through intrauterine sources or
other naturally and synthetically-
generated immunoglobulins
(antibodies)
see chapter 12
for active vs
passive

19. Active Immunity
 Humoral immunity (IgG, IgA, IgM)
available in the blood
 Mucosal immunity (secretory IgA)
available in the mucus of the GI,
respi and urogenital tracts
 Cell-mediated immunity
(T-lymphocytes)
 Type I hypersensitivity reactions (IgE
response in mast cells found in
respiratory and GI tracts)
passive
immunity is lost;
active immunity
last longer

20. Primary and Secondary
Antibody Response

21. Class and Function of
Immunoglobulins (Antibodies)
 IgG – 75%
 IgA – 15%
 IgM – 10%
 IgE - <1%
 IgD - <1%

22. Class and Function of
Immunoglobulins (Antibodies)
 IgG – present in circulation
and tissue, first Ig produced
in secondary response,
crosses placenta
 IgA – present in circulation of
mucous secretions; prevents
adherence on mucosal surface
deficiency leads to a lot of skin
infections and mucous
membrane infections. secreted
through breast milk

23. Class and Function of
Immunoglobulins
 IgM – present in circulation; first
Ig of primary immune
response. Large and cannot
move to tissues
 IgE – present in mast cells,
mediates hypersensitivity
reactions
 IgD – lymphocytes

24. Active, Acquired Immunity
 A result of invasion by a foreign
substance OR through
inoculation of a less virulent
antigen
 Subsequent reinvasion
generates a greater response

25. Types of Acquired, Specific
Immunity
 Active (Natural) – contact with
antigen through clinical infection
 Active (Artificial) – immunization
with live or killed antigen
 Passive (Natural) –
transplacental transfer of
antibodies (lost at 3-6months)
 Passive (Artificial) – injection of
serum from immune globulin

26. Human Hypersensitivity
Reactions
 Type I – immediate or
anaphylactic
 Type II – cytolytic or cytotoxic
 Type III – immune complex
 Type IV – cell-mediated,
delayed 1&2 are immediate
3 is associated
with chronic
disease
4 is delayed

27. Human Hypersensitivity
Reactions
 Type I – Immediate/anaplylactic
 IgE initiated
 Mast cell degranulation →
histamine and leukotriene
release
 Reaction includes anaphylaxis,
atopic diseases such as
allergies and asthma, skin
reactions asthma is a type of
allergic disease under
sub category atopia

28. Causes of Anaphylaxis
 Drugs
 Foods
 Insect sting
 Allergy
 Latex allergy

29. Causes of Anaphylaxis
 Drugs – PCN, sulfonamides,
insulins, ASA, TCN, tetracycline
cephalosporins, (antibiotic)
chemotherapeutic agents,
NSAIDs
 Insects – wasps, bees, hornets,
ants

30. Causes of Anaphylaxis
 Foods – eggs, nuts, shellfish,
fish, chocolate, strawberries
 Animal Sera – tetanus, rabies,
diptheria, snake venom
antitoxins
 Therapeutic Treatments – blood
products, Iodine-based media

31. S & S of Anaphylaxis
 Hives, wheal-and-flare reaction,
itching
 Angioedema
 Dyspnea, wheezing
fainting  Syncope, ↓ BP, flushing
 N & V, diarrhea, abd pain
 Onset generally 5-30 mins after
antigen
 See Fig. 14-11 on p. 226

32. Treatment for Anaphylactic
Shock
 Epinephrine (SC, IM or IV) 0.5ml
1:10,000 IV for severe
 Remove antigen
 02 non rebreather mask best
source with out intabation
 Maintain vascular volume by ↑
legs, fluid resuscitation with NS
or LR
 Vasopressive agents such as
dopamine (Intropin)

33. Latex Allergy (Type I)
 Common in the U.S. population
 Incidence higher among HCWs
 An allergy to the natural latex
proteins and occurs within
minutes of exposure

34. Latex Allergy (Type I)
 Apparent relationship with
allergy to certain medications
including bananas, avocado,
apricot, papaya, kiwi
 S & S include dermatitis, itching,
urticaria, sneezing/coughing,
wheezing, vascular collapse

35. Latex Allergy

36. Other Type I Hypersensitivities
 Atopic conditions – a broad
category used to describe many
conditions that are IgE
stimulated. Includes hay fever,
asthma, and all conditions cited
hereafter
 To repeat, allergic rhinitis fits
here

37. Atopic Conditions (cont.)
 Atopic dermatitis – often
complaints of itchy skin. May be
dry. Lesions may develop.
Treatment includes ↓exposure
and the response. Cool
compresses, lubricants, avoid
scratching

38. Eczema – a form of atopic
dermatitis
Tx:
topical corticosteroids
avoid triggers
Gel sticks better
than creams or
lotions

39. Other Type I Hypersensitivities
 Urticaria – (hives) a systemic
response because of an
allergen
 Histamine → localized
vasodilation, transudation, and
flaring

40. Type I Hypersensitivities -
Urticaria
 Papules that tend to develop on
face, neck, ant. aspect of arms,
and abdomen, back
 Many causative agents
 Avoidance
 Cool compresses,
antihistamines

41. Urticaria

42. Type I Hypersensitivities
 Angioedema – similar to
urticaria but involves deeper
layers of skin and mucosa
 Areas affected are significant
and include eyelids, lips, tongue,
larynx, hands, feet, GIT, and
genitalia

43. Meds used for Allergies
 Antihistamines – H1 receptor
binding agents to ↓ sneezing,
rhinitis, itching. (Zyrtec, Allegra,
Claritin). Non-blood brain barrier
crossing.
 Benadryl (diphenhydramine)
does cross BBB if it crosses
BBB causes
drowsiness

44. Meds. cont
 Decongestants – relieve nasal
congestion to ↓ alpha-
adrenergic response at entrance
to venous plexus of turbinates.
(Sudafed, phenylephrine)
 Corticosteroids – topical, nasal
(Nasocort, Rhinocort)

45. Meds. cont.
 Inhaled steroids – fundamental
treatment for asthma. (Flovent,
Advair, Azmacort, Vanceril)
 Beta-agonists for bronchospasm
(Albuterol, salmeterol)

46. Meds. cont.
 Antipruritic Drugs: may be
applied topically such as
calamine lotion, camphor and
menthol
 Mast Cell-Stablizing Drugs:
inhibit the release of histamines
and leukotrienes (Cromolyn).
Used to treat allergic rhinitis and
asthma

47. Meds. cont
 Leukotriene inhibitors –
Leukotrienes contribute airway
edema, smooth ms. contraction
and inflammation. (Accolate,
Singulair) used for
allergic
rhinitis and
allergies

48. Type II Hypersensitivity
reactions
 Cytolytic or Cytotoxic
 IgG or IgM mediated
 Complement activated and cell
destruction occurs
 Examples of include hemolytic
anemia, Rh disease,
autoimmune hyperthyroidism,
myasthenia gravis, and blood
transfusion reactions

49. Blood Transfusion Reactions
 Occurs as a result of intravascular
hemolysis or RBCs and includes; H/
A, back pain, chest pain, N & V, ↑
HR, ↓ BP, hematuria, urticaria
 Probably IgM-based reaction
 Stop the blood and all the tubings
including blood death by kidney
 Notify the MD and the lab cloggingdue to
failure
by dead
 Maintain vascular RBC
 Fluid resuscitation access with new
bag of NS
 Save the urine

51. Type III Hypersensitivity
Reactions
 Immune Complex reactions
 Antigens and antibodies bind and
occlude capillaries causing urticaria,
arthritis, arteritis, glomerulonephritis
 Reactions can be localized or
systemic
 Systemic Lupus Erythmatosus
 Acute glomerulonephritis

52. SLE

53. Type IV Hypersensitivity
Reactions
 Cell-mediated, or Delayed
 Requires effective T-cell
functioning
TB testing
 Used with PPD testing - edema
and fibrin result in induration.
Also responsible for caseous
lesions that develop with
tubercle bacillus

54. Type IV Hypersensitivity
Reactions
 Contact dermatitis – a result of
contact with an allergen such as
lanolin, adhesive, topical
medications or plant toxins.
Latex allergy due to contact fits
here.
 Antibodies are formed with first
exposure; hypersensitivity
reactions occur with later
exposure

56. Hypersensitivity Reaction
Prevention
 Good assessment and health
history. Attending to all food,
medication and environmental
allergies
 Controlling the environment

57. Immunodeficiency Disorders
 Inadequate protection of the
body at the cellular, enzyme or
humoral level
 Primary – inadequate immune
cells with mostly genetic causes.
Apparent at birth. Most common
hypogammaglobulinemia
i.e. bubble boys

58. Immunodeficiency Disorders
 Secondary – obtained through
other causes such as
medication use and disease;
medication use by far the most
common cause i.e. steroids, chemo,
antibiotics, radiation,
spleenectomy