Lab 5 –Blood, Lymphatics and the Immune
Response
Gilbert Pitts, Ph.D., Joseph Schiller, Ph.D., James F. Thompson, Ph.D.
Objectives
 Examine:



Lymph node slide
Lymphatic vessels on charts and models
Blood slides




Differentiate red blood cells, platelets, neutrophils,
lymphocytes, monocytes, eosinophils, and basophils
Perform 2 differential WBC counts
Identify leukemia
Identify sickle cell anemia
 Understand blood typing (ABO and Rh systems)
 Calculate and interpret hematocrit/packed cell volume
The Lymphatic System
 Basic organization


Lymph fluid in lymph vessels
Lymphatic organs (red bone marrow, thymus, spleen,
lymph nodes, tonsils) with smaller collections of
lymphatic tissue in other organs
 Functions



Return interstitial fluid and proteins to the blood
Transport dietary fats to adipose tissue
Protect against cancer & infection
 Lymph Flow from smallest to largest:

Capillaries  vessels  trunks  ducts
 Lymph vessels anastomose and supply and drain
lymph nodes along their course
Lymph Flow Follows Venous Circulation
 Right head, arm, and
thorax drained by the
right lymphatic duct
into right subclavian
vein
R
L
 Left head, arm,
thorax, most of the
abdominal cavity and
both legs drained by
the thoracic duct into
the left subclavian
vein
The Lymph Node
 Connective
tissue capsule
with
trabeculae
extending from
cortex to
medulla
 Stroma – the
supportive
connective
tissue network
of reticular
fibers and
fibroblasts
trabeculae
capsule
Lymph Node Parenchyma
 Cortex - filled with
lymphocytes and
macrophages in
follicles


Outer edge of follicle
contains more T
cells
Inner germinal
center is the site of
B-cell proliferation
 Medulla - medullary
cords of lymphocytes,
macrophages, plasma
cells (activated B
cells)
Cortex
Medulla
Lymph
Node
Micrograph
Medulla
Cortex
Lymph Node Germinal Centers
germinal centers
The Formed Elements of the Blood:
 Leukocytes = White
Blood Cells

Granular leukocytes
(granulocytes)




neutrophils
eosinophils
basophils
Agranular leukocytes
(agranulocytes)


lymphocytes - T
cells, B cells
monocytes 
tissue
macrophages
Granular Leukocytes
Eosinophil
2-4%
Neutrophil
60-70%
Basophil
0.5-1%
Agranular Leukocytes
Lymphocyte
20-25%
Monocyte
3-8%
Leukocyte Life Span and Number
 5,000 - 10,000 WBC’s/mm3 blood
 RBC/WBC ratio 700/1
 Differential WBC count (a standard clinical lab report)




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Neutrophils 60-70%
Lymphocytes 20-25%
Monocytes 3-8%
Eosinophils 2-4%
Basophils 0.5-1%
 Abnormal proportions are correlated with different
types of disease processes
Differential WBC Count
l
2-4%
20-25%
l
60-70%
3-8%
0.5-1%
Leukocyte Identification
Agranular
Small
Spherical nucleus
Granular
Dark
Hidden nuc.
All have many large
granules in
cytoplasm &
multilobed nuclei
Basophil
Lymphocyte
Large
2+ lobes
Red gran.
Eosinophil
no large
granules in
cytoplasm
Monocyte
Faint gran.
Neutrophil
Composition of Blood
 Blood sample separates into
2 parts

plasma - straw colored
liquid on top


~55% of the volume
formed elements

~45% of the volume
•
•
red blood cells
buffy coat: white blood
cells and platelets
Hematocrit (Hct)
 Packed Cell Volume is the
% of the blood which is
RBC’s
Males: 40-54% (47%)
 Females: 38-46% (42%)

 Hct indicates the status of
RBC production, the state
of hydration, or various
disease states
Hematocrit Procedure
Blood Typing
 Antigen – any substance
which provokes specific
immune responses
 Antigenic determinants



Antigen parts which
trigger the specific
immune response
An antigen may be an
entire microbe or only
small structures such as
subregions of large
molecules
RBC antigens
(agglutinogens) are
membrane glycoproteins
Most “antigens” are
complex and express
multiple types of
antigenic determinants.
ABO Blood Types



2 glycoprotein agglutinogens, A & B
One gene from each parent, A, B or O
6 combinations - AA, AB, AO, BB, BO, OO (no agglutinogens)
ABO Blood Types
 Agglutinins
 Naturally occurring antibodies produced in response to the

agglutinogens not present in your blood
React in antigen-antibody response to blood not of your type


blood type AB = universal recipients
blood type O = universal donors
ABO System
Rh System
 Rh typing - Rhesus monkey


Those expressing Rh antigens are Rh+
Those without Rh agglutinogens are Rh



Normally, blood does not contain Rh agglutinins
Immune system only makes agglutinins in
response to specific exposure to Rh antigens
Rh sensitivity does not occur until second
transfusion
Hemolytic disease of the newborn (erythroblastosis
fetalis)
• many “blue babies” prior to WWII
Hemolytic Disease of the Newborn =
Erythroblastosis Fetalis
Perform Fingerstick and Transfer Blood
Slide Appearance
Blood Type
A
B
AB
O
Please Clean Up Your Work Area
 Place only lancet and capillary tubes in
designated sharps containers
 Place all other blood contaminated materials
(gloves, alcohol wipes, paper towels, etc.) in the
large red biohazard bucket at the front of the
room
 Place all other discards in regular trash
receptacles
 Disinfect your work area with the spray solution
after you have concluded your blood work.
Homework
o Complete and turn in the questions on pages 5-13
to 5-15
o Complete Assignment 5 on MasteringAandP.
End Lab 5