LYMPHATIC SYSTEM &

IMMUNITY

Lymphatic System

Functions

Fluid recovery

Drainage/return of interstitial fluids to

circulation

Immunity

Exposes antigens/foreign materials to immune

cells

2

Lymphatic System

Major structures

Lymph vessels

1 way flow (valves)

3

Lymphatic System

Major structures

Lymph nodes

Filters

Concentrate debris, bacteria

for accessibility to wbc’s

4

Lymphatic System

Major structures

Thymus

Maturation of T lymphocytes

Immunity (recognition of

foreign antigen)

5

Lymphatic System

Major structures

Spleen

Large organ for concentrating

antigen

Major site of antibody

production (by B

lymphocytes)

6

Quick Quiz: The lymphatic system

consists of all of these organs

EXCEPT…

A) Spleen

B) Thymus

C) Lymph nodes

D) Kidney

7

Defense & Immunity

3 primary lines of defense

Physical & chemical barriers

Body surfaces

Skin, mucous membranes, tears, natural flora,

etc.

Non-specific

8

Defense & Immunity

3 primary lines of defense

Physical & chemical barriers

Non-specific cellular responses

Inflammation

Phagocytes

Complement proteins

9

Inflammation

Effect Redness, swelling, pain, fever

Outcome Attraction & mobilization of immune components

Tissue repair

Debris cleanup

Destruction of invading microorganisms

inflammation

10

Phagocytes

Neutrophils & macrophages

11

Defense & Immunity

3 primary lines of defense

Physical & chemical barriers

Nonspecific cellular responses

Immune responses (specific responses)

Lymphocytes

T cells

Cell-mediated response / immunity

B cells

Antibody-mediated response (humoral

immunity)

12

Quick Quiz: Which of these is part of

the non-specific cellular defenses?

A) Inflammation

B) Mucous membranes

C) B cells

D) Macrophages

13

Quick Quiz: Which of these is part of

the specific immune responses?

A) Inflammation

B) Mucous membranes

C) B cells

D) Macrophages

14

Specific Immunity

Active vs. passive

Natural vs. artificial

15

Immune Response

Cell-mediated immunity

Antigen-presenting cells

(APC) detect pathogens,

then activate T cells

T helper (TH) cells…

Stimulate B cells

(humoral)

Stimulate other T cells

Cytotoxic “killer” T cells

(TC)

cell mediated immunity 16

Immune Response

Humoral immunity

TH cells activate B

lymphocytes

Antibody production in

response to antigen

Memory B cells can be

activated during

subsequent infections

humoral immunity 17

Memory

18

Immune Response

Antibody titers & vaccines

19

Quick Quiz: Which of these clinical

procedures is done because of the

concept shown on the previous slide?

A) Booster shots

B) IV antibiotic therapy

C) Anti-retroviral therapy

20