Download 12.1 Notes - Trimble County Schools

12.1 Notes
The Nature of Blood
Objectives
 List the A-B-O antigens and antibodies found in the
blood for each of the four blood types: A, B, AB, and
O.
 Understand and describe how whole blood is typed
 Understand the concept of antigen-antibody
interactions and how it is applied to species
identification and drug identification
Blood
 A mix of cells, enzymes, proteins, and
inorganic substances
 Plasma – 55%
 Liquid, primarily water
 Solid portion 45%
 Red Blood cells – erythrocytes
 White blood cells – leukocytes
 Platelets
Serum
 The pale yellowish liquid that
makes up part of the blood clot
 Pertinent to forensics
Red blood cells
Blood serum
Antigens
 Chemical structures found on the
surface of the red blood cell
 Impart blood-type characteristics
 15 blood antigen systems have been
identified
 More common are ABO and Rh (D)
Antigens
 Type A blood contains A antigens
 Type B = B antigens
 Type AB = both A and B antigens
 Type O = neither A or B
 Rh+ indicates the presence of D antigen
 Rh- indicates the absence of D antigen
Antibodies
 Proteins that act against certain
antigens
 Serum-containing antibody =
antiserum
 Considered bivalent
 Two reactive sites
 Causes agglutination (clumping)
Serology
 Study of antigen-antibody reactions
 US distribution of blood types:
 Type O – 43%
 Type A – 42%
 Type B – 12%
 Type AB – 3%
Donor Combinations
Blood Type
Donates to
Receives from
A
B
AB
O
A, AB
B, AB
AB
all
A, O
B, O
all
only O
Antibodies
 Produced to bind to an invading antigen
 Different antibodies are produced to attack
a particular antigen site
 Polyclonal – multiple antibodies that attack
different antigen sites
 May vary over time
 Monoclonal antibodies - designed to attack
only one site on an antigen
Process of producing monoclonals
(p.335)
 Inject mouse with a particular antigen
 Mouse spleen cells produce antibodies
 Spleen cells removed and fused to cancer
cells
 Combined cells are called hybridoma cells
 Hybridoma cells allowed to multiply and are
screened for antibody activity
Process continued
 Hybridoma that bear antibody activity of
interest are selected, removed and cultured
 Produce identical monoclonal antibodies in
endless supply
 Used to offer immunoassay test for certain
drugs and semen material
 Current and most well known use of
monoclonal antibodies is Rituxin (cancer
treatment)
12.1 Questions
1.
2.
3.
4.
5.
6.
7.
8.
Who discovered that blood is distinguishable by its group or type?
What blood factors are the most important for properly matching a donor
and recipient for a transfusion?
What technique supplanted blood typing for associating bloodstain
evidence with a particular individual?
What is plasma? What percentage of blood content does plasma
account for?
Which of the following types of cells are not contained in plasma?
A. Phagocytes
B. Leukocytes
C. Erthyrocytes
D. Platelets
What are antigens and antibodies? What part of the blood contains
antibodies?
Describe how antibodies and antigens determine one’s A-B-O blood type.
What is the fourth important antigen other than A, B, and O?