Ganong's Review of Medical Physiology, 23rd Edition

528 SECTION VICardiovascular Physiology

cells to clump (agglutinate), as shown in Figure 32–11. The

other agglutination reactions produced by mismatched

plasma and red cells are summarized in Table 32–4. Blood

typing is performed by mixing an individual’s red blood cells

with antisera containing the various agglutinins on a slide and

seeing whether agglutination occurs.

TRANSFUSION REACTIONS

Dangerous hemolytic transfusion reactions occur when

blood is transfused into an individual with an incompatible

blood type; that is, an individual who has agglutinins against

the red cells in the transfusion. The plasma in the transfusion

is usually so diluted in the recipient that it rarely causes agglu-

tination even when the titer of agglutinins against the recipi-

ent’s cells is high. However, when the recipient’s plasma has

agglutinins against the donor’s red cells, the cells agglutinate

and hemolyze. Free hemoglobin is liberated into the plasma.

The severity of the resulting transfusion reaction may vary

from an asymptomatic minor rise in the plasma bilirubin level

to severe jaundice and renal tubular damage leading to anuria

and death.

Incompatibilities in the ABO blood group system are sum-

marized in Table 32–4. Persons with type AB blood are “uni-

versal recipients” because they have no circulating agglutinins

and can be given blood of any type without developing a trans-

fusion reaction due to ABO incompatibility. Type O individu-

als are “universal donors” because they lack A and B antigens,

and type O blood can be given to anyone without producing a

transfusion reaction due to ABO incompatibility. This does

not mean, however, that blood should ever be transfused with-

out being cross-matched except in the most extreme emergen-

cies, since the possibility of reactions or sensitization due to

incompatibilities in systems other than ABO systems always

TABLE 32–3 Partial amino acid composition of normal human β chain, and some hemoglobins with
abnormal β chains.a

Positions on Polypeptide Chain of Hemoglobin

Hemoglobin 1 2 3 6 7 26 63 67 121 146

A (normal) Val-His-Leu Glu-Glu Glu His Val Glu His

S (sickle cell) Val

C Lys

GSan Jose Gly

E Lys

MSaskatoon Tyr

MMilwaukee Glu

OArabia Lys

aOther hemoglobins have abnormal α chains. Abnormal hemoglobins that are very similar electrophoretically but differ slightly in composition are indicated by the same let-
ter and a subscript indicating the geographic location where they were first discovered; hence, MSaskatoon and MMilwaukee.

FIGURE 32–9 Bilirubin. The abbreviations M, V, and P stand for
the groups shown on the molecule on the left in Figure 32–7.

FIGURE 32–10 Antigens of the ABO system on the surface
of red blood cells.

N

OH

OH

HC

NH

H

N

H 2 C CH

N

MV

M

V

P M

M

P

F

G

G

G

C

= fucose

= glucose

=N-acetylgalactosamine

= galactose

= lipid bilayer

= ceramide

F

G

G

G

G

C

H

antigen

F

G

G

G

G

C

G

A

antigen

F

G

G

G

G

G

C

B

antigen