6-RH Flashcards
(232 cards)
1
Q
Which blood group system is highly polymorphic immunogenic and antigenic
A
Rh blood group system
2
Q
What does polymorphic mean in the context of Rh blood group system
A
wide range of genetic variations or alleles within the population
3
Q
What is the result of polymorphism in Rh blood group system
A
diverse array of Rh antigens on red blood cells
4
Q
What does immunogenic mean in the context of Rh blood group system
A
ability of antigens to stimulate antibody production
5
Q
Who are especially affected by immunogenicity in Rh blood group system
A
Rh negative individuals exposed to Rh positive blood
6
Q
What does antigenic mean in the context of Rh blood group system
A
ability of a substance to be recognized by antibodies or T cells
7
Q
What do antigens have that allow immune system detection
A
epitopes
8
Q
What is the ability to stimulate immune response called
A
immunogenic
9
Q
What is the ability to be recognized by antibodies or T cells called
A
antigenic
10
Q
Are all immunogenic substances antigenic
A
yes
11
Q
Are all antigenic substances immunogenic
A
no
12
Q
Which blood group system is second only to ABO in transfusion importance
A
Rh blood group system
13
Q
What is a primary cause of hemolytic disease of the fetus and newborn
A
Rh blood group system
14
Q
Why does Rh blood group system cause hemolytic disease of fetus and newborn
A
anti D antibodies are immunoglobulin G and cross placenta
15
Q
What happens when anti D antibodies cross placenta
A
attack fetal red blood cells
16
Q
What is the principal antigen of Rh blood group system
A
D antigen
17
Q
What do Rh positive and Rh negative refer to
A
presence or absence of D antigen
18
Q
What antigens are also present in Rh blood group system
A
C and c antigens
19
Q
Which antigens are antithetical in Rh blood group system
A
E and e antigens
20
Q
What does Rh positive mean
A
red blood cells possess D antigen
21
Q
What does Rh negative mean
A
red blood cells lack D antigen
22
Q
What are the two primary sets of antithetical antigens in Rh blood group system
A
C and c antigens plus E and e antigens
23
Q
What does antithetical mean in blood group context
A
pair of antigens coded by different alleles of a single gene
24
Q
Where are antithetical antigens located
A
same gene locus
25
Who first described hemolytic disease of the newborn
French midwife in 1609
26
What was observed in the set of twins in 1609
one hydropic and stillborn one jaundiced and died of kernicterus
27
What is hydropic in fetal context
fetus has hydrops fetalis
28
What is hydrops fetalis
abnormal swelling due to fluid accumulation
29
What is the common cause of stillbirth in context
hydrops fetalis
30
What is kernicterus
bilirubin induced brain dysfunction
31
What is kernicterus a complication of
severe jaundice
32
What is kernicterus in newborns
brain damage due to severe jaundice
33
Who described a hemolytic transfusion reaction in 1939
Levine and Stetson
34
What happened to the obstetric patient in 1939
required transfusion after stillborn delivery
35
What was the result of transfusion from husband in 1939
acute hemolytic transfusion reaction
36
What did the mother’s serum do in 1939 case
agglutinated red blood cells of husband and 80 out of 104 ABO compatible donors
37
What did Levine and colleagues conclude in 1941
mother immunized by fetal antigen inherited from father
38
What was suggested as cause of erythroblastosis fetalis
maternal antibodies produced after exposure to fetal red blood cells
39
Who discovered anti Rh in 1940
Landsteiner and Wiener
40
What animal was anti Rh named after
rhesus monkey
41
How did Landsteiner and Wiener discover anti Rh
injected guinea pigs and rabbits with rhesus monkey red blood cells
42
What did the antibodies from rabbits and guinea pigs react with
red blood cells of 85 percent of human population
43
What was the reaction called when human cells reacted with animal antibodies
Rh positive
44
What percent of human population did not react with animal antibodies
15 percent
45
What was the term for those who did not react with animal antibodies
Rh negative
46
Was the antigen in humans the same as in rhesus monkey
no
47
Were the maternal antibodies identical to animal antibodies
no
48
Why is the term Rh used despite the error
term rhesus was widely adopted and simplified to Rh
49
Which blood group system is most important in transfusion medicine
ABO blood group system
50
Which blood group system discovery reduced hemolytic transfusion reactions
Rh blood group system
51
Which antigen in Rh blood group system is highly immunogenic
D antigen
52
What do Rh negative individuals produce after exposure to D positive blood
anti D antibodies
53
What happens during first exposure of Rh negative person to Rh positive blood
immune system recognizes D antigen as foreign and produces anti D antibodies
54
Is there an immediate reaction during first Rh positive transfusion to Rh negative person
no
55
What happens during second exposure of Rh negative person to Rh positive blood
preformed anti D antibodies attack D positive red blood cells
56
What can happen after second exposure to Rh positive blood in Rh negative recipient
severe hemolytic transfusion reaction
57
What is a possible outcome of severe hemolytic transfusion reaction
fatality
58
Who can develop anti D antibodies after receiving D positive blood
D negative individuals
59
How long after initial exposure can anti D antibodies develop
many years later
60
What is essential to prevent transfusion related complications
meticulous Rh D antigen matching
61
What is a life saving step in transfusion medicine
proper cross checking of Rh status
62
Why should Rh negative recipient not receive blood from Rh positive donor
immune system will produce anti D antibodies to attack D antigen
63
Who can safely receive blood from Rh negative donor
Rh positive individual
64
Why is transfusing Rh negative red cells to Rh positive recipient safe
Rh negative red blood cells do not carry D antigen
65
What happens if Rh negative person is exposed to Rh positive blood
immune system will remember D antigen and produce anti D antibodies
66
What happens on second exposure of Rh negative person to Rh positive blood
rapid immune attack and destruction of transfused red blood cells
67
Why is Rh matching critical in transfusion medicine
to prevent severe hemolytic reactions
68
What complication arises when Rh negative mother carries Rh positive fetus
Rh incompatibility
69
When does fetal blood enter maternal circulation
at time of delivery
70
What does mother develop after fetal blood enters circulation
significant titers of anti Rh antibodies
71
What happens if Rh negative mother carries Rh positive fetus for second time
anti Rh agglutinins cross placenta and cause hemolysis
72
What are anti Rh agglutinins
immunoglobulin G antibodies
73
What can anti Rh agglutinins cause in fetus
hemolytic disease of the newborn
74
What are possible outcomes for infant with hemolytic disease of the newborn
death in uterus severe anemia severe jaundice edema hydrops fetalis
75
What triggers production of anti D antibodies in Rh negative mother
fetal red blood cells entering maternal bloodstream
76
Does first pregnancy usually affect fetus with Rh incompatibility
no
77
When do maternal IgG anti D antibodies cross placenta
subsequent Rh positive pregnancies
78
What is the effect of maternal IgG anti D antibodies crossing placenta
destruction of fetal red blood cells
79
What does destruction of fetal red blood cells lead to
hemolytic disease of the fetus and newborn
80
What is administered to Rh negative mothers to prevent HDFN
Rh immunoglobulin
81
When is Rh immunoglobulin given during first pregnancy
during 28th week of gestation
82
Why is Rh immunoglobulin given during 28th week
prenatal procedures may disrupt placental barrier
83
When is Rh immunoglobulin given after delivery
within 72 hours if newborn is Rh positive
84
When is Rh immunoglobulin given after miscarriage or abortion
if fetal red cells may have entered maternal circulation
85
What are complications of hemolytic disease of the fetus and newborn
severe jaundice kernicterus hydrops fetalis
86
What is kernicterus
brain damage caused by high bilirubin levels
87
What is hydrops fetalis
abnormal fluid accumulation in two or more areas of fetus or newborn
88
What is a common cause of stillbirth in context of Rh incompatibility
hydrops fetalis
89
What theory proposes Rh locus consists of three closely linked genes on a single chromosome
Fisher-Race theory
90
What does each gene encode in Fisher-Race theory
one antigen
91
How are genes inherited in Fisher-Race theory
as a three-locus haplotype
92
What theory suggests a single gene locus produces one gene product expressing multiple antigenic specificities
Wiener theory
93
How many genes control Rh protein expression on chromosome 1
two closely linked genes
94
Which gene codes for RhD proteins
RHD gene
95
Which gene codes for RhCE RhCe RhcE and Rhce proteins
RHCE gene
96
On which chromosome and bands are RHD and RHCE genes located
chromosome 1 short arm bands 34 to 36
97
Which gene important for Rh antigen expression is located on chromosome 6
RHAG gene
98
What does RHAG gene produce
Rh-associated glycoproteins
99
What is the glycosylation status of Rh-associated glycoproteins
glycosylated
100
What role does RHAG play in Rh antigen expression
co-expressor necessary for successful expression
101
Does RHAG gene express Rh antigens
no
102
Where is RHAG gene located
short arm of chromosome 6 bands 11 to 21.1
103
How many exons do RHD and RHCE genes have
10 exons each
104
What are exons
coding regions of genes expressed in mRNA
105
What genes are present in Rh positive individuals
both RHD and RHCE genes
106
What genes are present in Rh negative individuals
only RHCE gene
107
What is the hydrophobicity of Rh proteins
extremely hydrophobic
108
What is the glycosylation status of RhD and RhCE proteins
nonglycosylated
109
How many times do Rh antigens span the red blood cell membrane
12 times
110
How many amino acids compose RhD and RhCE proteins
416 amino acids
111
How many amino acids differ between RhD and RhCE proteins
32 to 35 amino acids
112
What molecular weight range do Rh proteins migrate at in SDS-PAGE
30
113
What part of Rh proteins is exposed on red blood cell surface
small extracellular loops
114
What determines serologic differences between Rh blood types
conformation of extracellular loops and amino acid sequence
115
What is the molecular weight range of Rh-associated glycoprotein
40
116
Which amino acid position determines uppercase and lowercase C antigen expression
position 103
117
Which amino acid position differentiates uppercase and lowercase E antigen
position 226
118
What amino acid at position 103 corresponds to uppercase C antigen
serine
119
What amino acid at position 103 corresponds to lowercase c antigen
proline
120
What amino acid at position 226 corresponds to uppercase E antigen
proline
121
What amino acid at position 226 corresponds to lowercase e antigen
alanine
122
What chromosome arm and bands are RhD and RhCE genes located
short arm of chromosome 1 bands 34 to 36
123
What cell type exclusively expresses RhD RhCE and RhAG proteins
red blood cells
124
What functions do RhD RhCE and RhAG proteins perform
transmembrane proteins maintaining red blood cell structural integrity and transporters
125
What molecules might Rh proteins transport
ammonia and possibly carbon dioxide
126
What does Rh phenotype refer to
observable traits based on presence or absence of Rh antigens on red blood cells
127
What genotype results in Rh positive phenotype
one or two codominant RHD genes D/d or D/D
128
How many RHCE genes are inherited by an individual
two one from each parent
129
What haplotypes express Rh positive phenotype
DCe/DcE DCe/dce dce/DcE
130
What haplotype expresses Rh negative phenotype
dce/dce
131
From which ethnicities do Rh negative mutations arise
European African Asian
132
What causes Rh negative phenotype
deletion mutation or replacement of RHD gene leading to absence of D antigen
133
Which nomenclature uses CDE terminology for Rh antigens
Fisher-Race nomenclature
134
Who developed Fisher-Race nomenclature
Ronald Fisher and Robert Race
135
How many gene complexes exist at Rh locus according to Fisher-Race
eight
136
Which nomenclature uses Rh-Hr terminology
Wiener nomenclature
137
How many alleles exist at each gene locus in Wiener nomenclature
eight
138
What does Rosenfield nomenclature assign to Rh1 antigen
D antigen
139
What does Rosenfield nomenclature assign to Rh2 antigen
C antigen
140
What does Rosenfield nomenclature assign to Rh3 antigen
E antigen
141
What does Rosenfield nomenclature assign to Rh4 antigen
c antigen
142
What does Rosenfield nomenclature assign to Rh5 antigen
e antigen
143
What numeric system assigns a six digit number to each blood group
International Society of Blood Transfusion numeric terminology
144
What do the first three digits represent in ISBT numeric terminology
blood group system
145
What do the last three digits represent in ISBT numeric terminology
antigenic specificity
146
What number is assigned to the Rh blood group system in ISBT numeric terminology
4
147
How many times do Rh antigens pass through the red blood cell membrane
12 times
148
What type of proteins are Rh antigens
transmembrane proteins
149
Where are Rh antigens found
only on red blood cells
150
Are Rh antigens soluble or expressed on other cells
no
151
When are Rh antigens well developed
at birth
152
What disease can Rh antigens cause
hemolytic disease of the fetus and newborn
153
Which Rh antigen is the most immunogenic
D antigen
154
How many antigens comprise the Rh blood group system
56 antigens
155
What are the five common Rh antigens
D C E c e
156
Does D antigen have an allele
no
157
What are alleles in Rh system
C and c are alleles and E is allelic to e
158
What volume of Rh positive red blood cells can stimulate antibody production in Rh negative person
less than 0.1 milliliters
159
What percentage of general population is Rh positive
85 percent
160
What percentage of general population is Rh negative
15 percent
161
What is the order of potency of Rh antigens from most to least
D c E C e
162
Which gene encodes C c E and e antigens
RHCE gene
163
What is codominance in RHCE alleles
both haplotypes are expressed on red blood cells
164
What term describes weaker expression of D antigen requiring indirect antiglobulin test
Weak D
165
What was Weak D previously called
Du
166
What phenotype includes C in trans to RHD Weak D Partial D and Del
weakened D phenotypes
167
What is C in trans to RHD
genetic interaction of alleles on opposite chromosomes affecting D antigen expression
168
What causes interference in D antigen expression in C in trans to RHD
steric hindrance and membrane protein folding
169
What antibodies are used in Weak D antigen testing
monoclonal immunoglobulin M and immunoglobulin G antibodies
170
What does monoclonal immunoglobulin M detect in Weak D testing
D antigen during immediate spin
171
What does immunoglobulin G detect in Weak D testing
D antigen in antiglobulin phase
172
What causes quantitative changes in Weak D phenotype
fewer D antigen sites due to mutations
173
Where do mutations causing Weak D occur
transmembrane or intracellular regions of RHD protein
174
How many types of Weak D mutations are identified
over 50 types
175
Which Weak D types are most common in European ancestry
types one two and three
176
Do Weak D individuals usually make anti D antibodies
rarely
177
Why do Weak D individuals rarely make anti D
immune system recognizes altered D antigen as self
178
What is Partial D also called
D mosaic
179
What causes Partial D phenotype
missing or altered D epitopes due to genetic recombination replacing parts of RHD with RHCE gene
180
What is the immune consequence of Partial D
production of anti D antibodies after exposure to normal Rh positive blood
181
Who developed categories for Partial D phenotypes
Tippett and Sanger
182
How many categories did Tippett and Sanger create for Partial D
seven labeled I to VII
183
What is Del phenotype
D antigen not detected by routine methods but proven by absorption and elution techniques
184
In which population is Del phenotype common
Asian population
185
What test detects Del phenotype
absorption/elution and molecular testing
186
What causes Del phenotype
mutations reducing RHD protein expression affecting folding transport or stability
187
Can Del individuals produce anti D antibodies
yes due to very low antigen expression
188
Why is Del screening important in blood donation
to prevent alloimmunization in true Rh D negative recipients
189
What type of antibodies are Rh antibodies
immune antibodies after exposure to Rh antigens
190
Do Rh antibodies occur naturally
no
191
What immunoglobulin class are most Rh antibodies
immunoglobulin G
192
Why do Rh antibodies not react in saline medium
mostly immunoglobulin G class
193
At what temperature do Rh antibodies react best
37 degrees Celsius
194
What are first-order Rh antibodies
saline agglutinins bivalent complete antibodies
195
What is a key feature of first-order Rh antibodies
visible agglutination in saline
196
Are first-order Rh antibodies common
no
197
What are second-order Rh antibodies
albumin-reacting incomplete monovalent antibodies
198
What is a key feature of second-order Rh antibodies
no agglutination in saline but visible in protein media
199
What immunoglobulin class are second-order Rh antibodies
immunoglobulin G and monovalent
200
What are third-order Rh antibodies
typical Rh antibodies antiglobulins
201
Where do third-order Rh antibodies react
antiglobulin medium only
202
When was the LW blood group system first recognized
at the time Rh antigens were first recognized
203
What antibody was renamed anti-LW
antibody from injecting rhesus monkey red cells into guinea pigs and rabbits
204
How does anti-LW antibody behave in testing
reacts strongly with Rh positive red blood cells and weakly or not at all with Rh negative cells
205
What phenotype is negative for LW blood group system
Rh null phenotype lacking all Rh antigens
206
Where is LW gene located
chromosome 19
207
What are the three alleles of LW gene
LWa LWb LW amorph
208
Which LW allele is common
LWa
209
Which LW allele is rare
LWb
210
What is LW amorph allele
does not produce any LW antigen
211
What was CW originally considered
allele at C/c locus
212
What causes CW antigen
single amino acid change on RhCe protein
213
What percentage of Caucasians have CW antigen
about 2 percent
214
Is CW common in African Americans
no very rare
215
Can anti-CW antibody form naturally
yes without known exposure
216
What is the relationship between CW and Cc antigens
phenotypic coexistence and antithetical to MAR antigen
217
What is dosage effect in CW antigen
stronger reaction when homozygous for CW
218
What is F antigen
compound antigen expressed when c and e are present on same haplotype
219
What is origin of F antigen
conformational change of RhCe protein on same haplotype
220
What is clinical significance of F antigen
can cause hemolytic disease of fetus and newborn and transfusion reactions
221
What is RHI antigen
compound antigen present when c and e are on RhCe protein
222
Which haplotypes react with anti-RHI
DCe or Ce haplotypes
223
Are antibodies to cE and CE common
no rarely seen
224
What is G antigen
present on most D positive and all C positive red blood cells
225
How does anti-G antibody react
mimics combination of anti-C and anti-D
226
In which genotype was G antigen first described
rr genotype D negative person
227
Why is distinguishing anti-G from anti-D and anti-C important
to avoid inappropriate withholding of Rh immunoglobulin in prenatal setting
228
What is characteristic of E variants
e antigen positive phenotype producing anti-e antibodies
229
Which ethnic backgrounds commonly have E variants
African or mixed ethnic backgrounds
230
What are V and VS antigens
low prevalence antigens more common in African Americans
231
What percentage of African Americans have V antigen
about 30 percent
232
What percentage of African Americans have VS antigen
about 32 percent
